Pimoroni love the little SN3218A chip they used to make PiGlow so much that they've decided to turn it into a handy little breakout module. This is a super low-cost way to drive 18 LEDs at constant current up to 34mA per channel. Simply hook up the cathode of your LEDs to the channel and provide a common 5V supply for the anodes and away you go!

2.75 - 5.5V supply and logic voltage

Up to 34mA per channel constant current sinking (adjustable)

Bread-board compatible format

I2C interface (address 0x54)

Supplied with 0.1" headers to solder yourself

The I2C interface is very simple to use and works with Raspberry Pi, Arduino, and most other platforms - the device address is 0x54. With the Raspberry Pi you can use the 3V3 supply to power the chip (via the VCC pin on the breakout board) and the 5V supply to power the LEDs. There is also an Arduino library available

This programmable module combines with a Raspberry Pi to serve as the control center of a small robot or electronics project. Its ATmega32U4 AVR microcontroller comes preloaded with an Arduino-compatible bootloader, and the board includes dual motor drivers that can deliver 1.7 A per channel to two brushed DC motors. An efficient voltage regulator (5.5 V to 36 V input) and level shifters enable it to power and communicate with a Raspberry Pi. This version (item #3119) is assembled with selected through-hole connectors and components installed for use as a Raspberry Pi add-on.

A-Star 32U4 Robot Controller SV with Raspberry Pi Bridge, bottom view with dimensions.

The A-Star 32U4 Robot Controller SV with Raspberry Pi Bridge is a programmable module well-suited for robotics applications, designed to work either as an auxiliary controller mounted to a Raspberry Pi or as a standalone control solution for a small robot. This A-Star (abbreviated A*) is based on the ATmega32U4 AVR microcontroller from Microchip (formerly Atmel), which has built-in USB functionality, and it ships with a preloaded Arduino-compatible bootloader. Its complement of peripheral hardware includes dual motor drivers capable of delivering a continuous 1.7 A per channel, along with pushbuttons, LEDs, and an optional buzzer for building a user interface. An efficient switching voltage regulator allows the controller to work over a wide range of input voltages (5.5 V to 36 V).

The robot controller board conforms to the Raspberry Pi HAT specification, allowing it to be used as an add-on for a Raspberry Pi with a 40-pin GPIO header (Model B+ or newer, including Pi 3 Model B and Model A+). On-board level shifters make it easy to set up I²C communication and interface other signals between the two controllers, and the A-Star automatically supplies 5 V power to an attached Raspberry Pi. In this setup, the Raspberry Pi can handle the high-level robot control while relying on the A-Star for low-level tasks like reading analog sensors and controlling timing-sensitive devices (e.g. servos).

We provide a library that helps establish communication between the A-Star and a Raspberry Pi, as well as a tutorial that demonstrates how to use the library and its included example code to build such a robot.

Our comprehensive user’s guide provides the basics you need to get started with the A-Star as well as detailed technical information for advanced users.

This product requires a USB A to Micro-B cable (not included) to connect to a computer.

Driving motors with an A-Star 32U4 Robot Controller SV with Raspberry Pi Bridge on a Raspberry Pi Model B+ or Pi 2 Model B.

A-Star 32U4 Robot Controller SV (5.5 V to 36 V) configurations:

Item #3118: Surface mount components only (no through-hole components or mounting hardware)

Item #3119: Assembled with selected through-hole components for use as a Raspberry Pi add-on (Raspberry Pi mounting hardware included)

A-Star 32U4 Robot Controller LV (2.7 V to 11 V) configurations:

Item #3116: Surface mount components only (no through-hole components or mounting hardware)

Item #3117: Assembled with selected through-hole components for use as a Raspberry Pi add-on (Raspberry Pi mounting hardware included)

Dimensions: 65 mm × 56 mm (2.6″ × 2.2″)

Programmable ATmega32U4 MCU with 32 KB flash, 2.5 KB SRAM, 1 KB EEPROM, and native full-speed USB (clocked by precision 16 MHz crystal oscillator)

Preloaded with Arduino-compatible bootloader (no external programmer required)

All 26 general-purpose I/O lines from the ATmega32U4 are broken out (including PB0, PD5, and PE2); 7 of these can be used as hardware PWM outputs and 12 of these can be used as analog inputs (some I/O lines are used by on-board hardware)

Convenient 0.1″-spaced power, ground, and signal connection points

Dual bidirectional MAX14870 motor drivers (1.7 A continuous per channel, 2.5 A peak per channel)

Buzzer option for simple sounds and music

3 user-controllable LEDs

3 user pushbuttons

Reset button

Level shifters for interfacing 5 V logic to 3.3 V Raspberry Pi

Power features:

5 V power can be sourced from USB or from 5.5 V to 36 V external supply through on-board regulator (with several access points for connecting external power)

Switching 5 V regulator enables efficient operation

Power switch for external power inputs

Reverse-voltage protection on external power inputs

Power selection circuit allows for seamless switching between power sources while providing overcurrent protection, and feedback about which power source is selected

Provides 5 V power to Raspberry Pi

5 V power can be sourced from USB or from 5.5 V to 36 V external supply through on-board regulator (with several access points for connecting external power)

Switching 5 V regulator enables efficient operation

Power switch for external power inputs

Reverse-voltage protection on external power inputs

Power selection circuit allows for seamless switching between power sources while providing overcurrent protection, and feedback about which power source is selected

Provides 5 V power to Raspberry Pi

6-pin ISP header for use with an external programmer

Comprehensive user’s guide

A-Star 32U4 Robot Controller SV with Raspberry Pi Bridge with included hardware.

This version of the A-Star 32U4 Robot Controller SV with Raspberry Pi Bridge (5.5 V to 36 V input voltage) is assembled with selected through-hole connectors and components for use as a Raspberry Pi expansion board, as shown in the picture above. A 2×20-pin 0.1″ female header is preinstalled to serve as a Raspberry Pi GPIO connector, and a 6-pin strip of terminal blocks and a DC power jack are mounted for motor and power connections. A buzzer is also installed, along with two 2×1-pin male headers and shorting blocks for the buzzer and battery level jumpers.

This version ships with a set of four M2.5 standoffs (11 mm length), screws, and nuts that can be used to secure the board to the Raspberry Pi at the proper height for the GPIO connector.

For a version with SMT components only, making it more suitable for standalone use and allowing customization of through-hole components, see item #3118. For example, if you want to continue to have access to the Raspberry Pi’s 40 GPIO pins while the A-Star is plugged in, you can get the SMT-only version and install a stackable 2×20-pin female header.

A major feature of the A* Robot Controller SV is its power system, which allows it to efficiently operate from a 5.5 V to 36 V external source and provide power to an attached Raspberry Pi. The input voltage is regulated to 5 V by an MP4423H switching step-down (buck) converter from Monolithic Power Systems. (We also make a standalone regulator based on this integrated circuit.)

As shown in the left graph below, the SV’s 5 V switching regulator has an efficiency – defined as (Power out)/(Power in) – of 80% to 95% for most combinations of input voltage and load.

The A-Star’s components, including the microcontroller and LEDs, draw 30 mA to 40 mA in typical applications (without the buzzer). The rest of the regulator’s achievable output current, which depends on input voltage as well as ambient conditions, can be used to power other devices; this can include an attached Raspberry Pi (which typically draws a few hundred milliamps). The green line in the right graph above shows the output currents where the regulator’s output voltage drops below 4.75 V. These currents are close to the limits of the regulator’s capability and generally cannot be sustained for long periods; under typical operating conditions, a safe limit for the maximum continuous regulator output current is 60% to 70% of the values shown in the graph.

The dropout voltage of a step-down regulator is defined as the minimum amount by which the input voltage must exceed the regulator’s target output voltage in order to assure the target output can be achieved. As can be seen in the graph below, the dropout voltage of the Robot Controller SV’s regulator increases approximately linearly with the output current. For light loads where the dropout voltage is small, the board can operate almost down to 5 V. However, for larger loads, the dropout voltage should be taken into consideration when selecting a power supply; operating above 6 V will ensure the full output current is available.

Note: Batteries can have much higher voltages than their nominal voltages when fully charged, so be careful with nominal voltages above 24 V. A 36 V battery is not appropriate for this product.

Like our other A-Star 32U4 programmable controllers, the A-Star 32U4 Robot Controller ships with a preloaded Arduino-compatible bootloader (which uses 4 KB of flash memory, leaving 28 KB available for the user program). We provide a software add-on that enables the board to be easily programmed from the Arduino environment and an Arduino library to make it easy to use the additional on-board hardware.

The A-Star 32U4 Robot Controller has the same microcontroller as the Arduino Leonardo and Arduino Micro, and it runs at the same frequency, so most code examples intended for those boards should also work on the A-Star.

The A-Star 32U4 Robot Controller is a part of our larger A-Star 32U4 family, all of whose members are based on the same ATmega32U4 microcontroller, feature native USB interfaces, and are preloaded with Arduino-compatible bootloaders. The table below shows some key features and specifications of our A-Star microcontroller boards to help you choose the right one for your application.

People often buy this product together with:

So you have a Teensy and a RGB LED Matrix Panel and you want an easy way to add graphics to your matrix without having to toss aside your Teensy or do too much soldering. Enter the SmartMatrix SmartLED Shield (V4) for Teensy 3.2, 3.5, or 3.6 (not the Teensy LC)!

The SmartLED Shield gives you an easy way to connect up a Teensy 3.2, Teensy 3.5, or Teensy 3.6 to one of our RGB LED Matrix Panels. The example sketches included with the SmartMatrix Library will get you started quickly displaying graphics, patterns, or even animated GIFs from a microSD card on your panel.

Features

Shield is fully assembled, no soldering required (besides adding pins to the Teensy)

HUB75 pinout, connects to panel directly or using panel's ribbon cable

5V level shifters for better compatibility with 5V panels

Support for driving Dotstar/APA102 LEDs in parallel with the LED panel, connects directly to 4-pin JST SM cable on Dotstar LEDs, or use the included cable

Expansion rows for main Teensy pins, making signals available for prototyping

Teensy is easily removed from the shield

Note: compared to previous versions of the SmartMatrix Shield, the microSD card slot was removed, as it is redundant when combined with the Teensy 3.5/3.6

The shield brings the 13 I/O signals needed to drive the panel out to a connector that matches the pinout on the panel, and brings the rest of the I/O signals out to convenient expansion headers.  The board includes pre-soldered 5V level shifters.

It's a great board for easily expanding your Teensy's capabilities. You'll also need to program in your Teensy with the SmartMatrix code available on the project website.

Add some jazz & pizzazz to your project with a color touchscreen LCD. This TFT display is 2.4" diagonal with a bright (4 white-LED) backlight and it's colorful! 240x320 pixels with individual RGB pixel control, this has way more resolution than a black and white 128x64 display.

As a bonus, this display has a resistive touchscreen attached to it already, so you can detect finger presses anywhere on the screen.

If you need a larger touchscreen, check out the 2.8" diagonal or 3.5" diagonal TFT breakouts. For a smaller display, see our non-touch 2.2" or 1.8" or 1.44" diagonal TFTs

This display has a controller built into it with RAM buffering, so that almost no work is done by the microcontroller. The display can be used in two modes: 8-bit or SPI. For 8-bit mode, you'll need 8 digital data lines and 4 or 5 digital control lines to read and write to the display (12 lines total). SPI mode requires only 5 pins total (SPI data in, data out, clock, select, and d/c) but is slower than 8-bit mode.

In addition, 4 pins are required for the touch screen (2 digital, 2 analog) or you can purchase and use our resistive touchscreen controller (not included) to use I2C or SPI.

Of course, we wouldn't just leave you with a datasheet and a "good luck!". For 8-bit interface fans we've written a full open source graphics library that can draw pixels, lines, rectangles, circles, text, and more. For SPI users, we have a library as well, its separate from the 8-bit library since both versions are heavily optimized. For resistive touch, we also have a touch screen library that detects x, y and z (pressure) and example code to demonstrate all of it. Check out our tutorial for wiring diagrams, schematics, and a walkthough on this display.

Do you make time to talk to your Arduino? Maybe you should! The EasyVR Shield 3.0 is a voice recognition shield for Arduino boards integrating an EasyVR module. It includes all of the features of the EasyVR module in a shield form factor that simplifies connection to the Arduino main board and PC.

EasyVR 3.0 is a multi-purpose speech recognition module designed to add versatile, robust and cost effective speech and voice recognition capabilities to virtually any application. EasyVR is the third generation version of the successful VRbot module and builds on the features and functionality of its predecessor. In addition to the EasyVR 3.0 features like up to 32 user-defined Speaker Dependent (SD) commands and 26 built-in speaker independent (SI) commands for ready to run basic controls, the shield has an additional audio line-out/headphone jack, and access to the I/O pins of the EasyVR module.

Note: Unlike V2.0, the EasyVR Shield 3.0 does not come preassembled and will require some soldering and assebly before operation.

Features

A selection of 26 built-in Speaker Independent (SI) commands (available in US English, Italian, Japanese, German, Spanish, and French) for ready to run basic controls.

Supports up to 32 user-defined Speaker Dependent (SD) triggers or commands (any language) as well as Voice Passwords.

With the optional Quick T2SI Lite license you can add up to 28 Speaker Independent (SI) Vocabularies, each one with up to 12 SI different commands. Therefore an overall number of up to 336 additional SI commands!

SonicNet to control one or more EasyVR 3.0s wirelesly with sound tokens generated by the module or other sound source

DTMF tone generation

Easy-to-use and simple Graphical User Interface to program Voice Commands to your robot.

Compatible with Arduino boards that have the 1.0 Shield interface (UNO R3) and legacy boards including:

Arduino Duemilanove

Arduino Uno

Arduino Mega

Arduino Leonardo

Arduino Due

Arduino Duemilanove

Arduino Uno

Arduino Mega

Arduino Leonardo

Arduino Due

Module can be used with any host with an UART interface (powered at 3.3V - 5V).

Supports direct connection to the PC on main boards with a separate USB/Serial chip and a special software-driven “bridge” mode on boards with only native USB interface, for easy access by the EasyVR Commander.

Simple and robust serial protocol to access and program the module through the host board.

Make your own sound tables using Sensory QuickSynthesis4 tool.

Supports remapping of serial pins used by the Shield (in SW mode).

The new EasyVR GUI includes a command to process and download custom sound tables to the module (overwriting existing sound table)

Provides a 3.5mm audio output jack suitable for headphones or as a line out

8 ohm speaker output

Access to EasyVR I/O pins

LED to show feedback during recognition tasks

Live message recording and Fast SD/SV recognition

Arduino Libraries provided

The SparkFun H2OhNo! is a water sensor alarm kit that you build yourself. When water is detected across the sense pins an alarm goes off and an LED starts blinking. If you’ve ever had a water heater explode or tried to create submersible electronics you know how important it is to be able to detect when water is around!

Underneath the default function of H2OhNo! is a small but powerful development board for the ATtiny85 microcontroller. The board includes a buzzer, LED, a coin cell battery, and the ability to detect analog and digital sensors. This mixture of parts creates a great low-cost tool to learn how to program and sense things!

This board can be re-programmed to be an Annoy-A-Tron (originally made by Think Geek). Please annoy respectfully, otherwise your board may get demolished.

Note: Please check the hookup guide below for helpful tips and assembly instructions.

Note: Due to the requirements of shipping the battery in this kit, orders may take longer to process and therefore do not qualify for same-day shipping. Additionally, these batteries can not be shipped via Ground or Economy methods to Alaska or Hawaii. Sorry for any inconvenience this may cause.

Get Started with the H2OhNo! Guide

Includes

1x H2OhNo! PCB

1x ATtiny85 (Pre-Programmed)

1x 20mm Coin Cell Battery Holder

1x CR2032 Coin Cell Battery

1x Slide Switch

1x 2kHz Piezo Speaker

1x 8-pin DIP Socket

1x Super Bright Red LED

2x Jumper Wire

1x Capacitor 0.1uF

Features

22.86mm x 52.07mm (0.90" x 2.05")

Make a scrolling sign, or a small video display with this 8x8 gridded bi-color LED matrix. Only 1.2" on a side, it is quite visible but not so large it wont plug into a breadboard! 128 LEDs are contained in the plastic body, 64 red 320mcd and 64 green, in an 8x8 matrix. Every grid has two LEDs inside so you can have it display red, green, yellow or with fast multiplexing any color in between. This display is bright, beautiful and funky with nice diffused square lenses for a striking look. There are 24 pins on the side, 12 on each, with 0.1" spacing so you can easily plug it into a breadboard with one row on each side for wiring it up.

Since the display is in a grid, you'll need to 1:8 multiplex control it. We suggest either using two 74HC595s and TPIC6B595 (using the 74HC' to control the 16 anodes at once and then using the TPIC' to drive one cathode at a time) or using two MAX7219 which will do the multiplexing work for you.

The Arduino playground has a nice set of tutorials introducing the MAX7219 and 8x8 LED matrices

What's better than a single LED? Lots of LEDs! A fun way to make a small colorful display is to use a 1.2" Bi-color 8x8 LED Matrix. Matrices like these are 'multiplexed' - so to control all the 128 LEDs you need 24 pins. That's a lot of pins, and there are driver chips like the MAX7219 that can help control a matrix for you but there's a lot of wiring to set up and they take up a ton of space. Here at Adafruit we feel your pain! After all, wouldn't it be awesome if you could control a matrix without tons of wiring? That's where these adorable LED matrix backpacks come in. We have them in three flavors - a mini 8x8, 1.2" Bi-color 8x8 and a 4-digit 0.56" 7-segment. They work perfectly with the matrices we stock in the Adafruit shop and make adding a bright little display trivial. It's called a Bicolor LED, but you can have 3 colors total by turning on the red and green LEDs, which creates yellow-orange. That's 3 colors for the price of 2!The matrices use a driver chip that does all the heavy lifting for you: They have a built in clock so they multiplex the display. They use constant-current drivers for ultra-bright, consistent color, 1/16 step display dimming, all via a simple I2C interface. The backpacks come with address-selection jumpers so you can connect up to four mini 8x8's or eight 7-segments/bicolor (or a combination, such as four mini 8x8's and two 7-segments and two bicolor, etc) on a single I2C bus.The product kit comes with:

A fully tested and assembled LED backpack

1.2" Bi-color 8x8 LED Matrix

4-pin header

A bit of soldering is required to attach the matrix onto the backpack but its very easy to do and only takes about 5 minutes.Of course, in classic Adafruit fashion, we also have a detailed tutorial showing you how to solder, wire and control the display. We even wrote a very nice library for the backpacks so you can get running in under half an hour, displaying images on the matrix or numbers on the 7-segment. If you've been eyeing matrix displays but hesitated because of the complexity, his is the solution you've been looking for!

Design a clock, timer or counter into your next project using our pretty 4-digit seven-segment display. These bright crisp displays are good for adding numeric output. Besides the four 7-segments, there are decimal points on each digit and an extra wire for colon-dots in the center (good for time-based projects).These are 18mcd bright. You can drive these with less current to get the same brightness to save power, or crank them up to 20mA and have them at their brightest.These displays are multiplexed, common-cathode. What that means it that you can use a 74HC595 or just 8 microcontroller pins if you can spare them to control the 8 anodes (7-seg + decimal) at about ~15mA each, and then connect NPN transistors or a TPIC6B595 to the cathodes to sink the 8*15mA = ~160mA maximum per digit.

We strongly recommend getting our backpack version, which comes with an LED driver on the back. This version is just the raw display, and requires a lot more work to get running!These come in a bright red color, we also have many other sizes and colors!

Design a clock, timer or counter into your next project using our pretty 4-digit seven-segment display. These bright crisp displays are good for adding numeric output. Besides the four 7-segments, there are decimal points on each digit and an extra wire for colon-dots in the center (good for time-based projects).These are 15mcd bright. You can drive these with less current to get the same brightness to save power, or crank them up to 20mA and have them at their brightest.These displays are multiplexed, common-cathode. What that means it that you can use a 74HC595 or just 8 microcontroller pins if you can spare them to control the 8 anodes (7-seg + decimal) at about ~15mA each, and then connect NPN transistors or a TPIC6B595 to the cathodes to sink the 8*15mA = ~120mA maximum per digit.

We strongly recommend getting our backpack version, which comes with an LED driver on the back. This version is just the raw display, and requires a lot more work to get running!

These come in a bright blue color, we also have many other sizes and colors!

Design a clock, timer or counter into your next project using our pretty 4-digit seven-segment display. These bright crisp displays are good for adding numeric output. Besides the four 7-segments, there are decimal points on each digit and an extra wire for colon-dots in the center (good for time-based projects).These are 30mcd bright. You can drive these with less current to get the same brightness to save power, or crank them up to 20mA and have them at their brightest.These displays are multiplexed, common-cathode. What that means it that you can use a 74HC595 or just 8 microcontroller pins if you can spare them to control the 8 anodes (7-seg + decimal) at about ~15mA each, and then connect NPN transistors or a TPIC6B595 to the cathodes to sink the 8*15mA = ~120mA maximum per digit.

We strongly recommend getting our backpack version, which comes with an LED driver on the back. This version is just the raw display, and requires a lot more work to get running!

These come in a bright white color, we also have many other sizes and colors!

This is not your basic 7-segment display. The Dual 7-Segment Display features two digits with an RGB LED in every single segment! You will now have a small 7-segment LED in your project with a full-color display!

The Dual 7-Segment Display is breadboard friendly and possesses a digit height of 0.56in (14.22mm). The red LEDs have a forward voltage of 2VDC, 2.85VDC for green, and 2.95VDC for blue, with a continuous forward current per segment of 10mA for the red LEDs and 5mA for the green and blue.

Your basic 7-segment LED. Common anode. Two decimal points, but only the one on the right is wired. Digit height is 0.6". Overall height is 1"

Round and round and round they go! 16 ultra bright smart LED NeoPixels are arranged in a circle with 1.75" (44.5mm) outer diameter. The rings are 'chainable' - connect the output pin of one to the input pin of another. Use only one microcontroller pin to control as many as you can chain together! Each LED is addressable as the driver chip is inside the LED. Each one has ~18mA constant current drive so the color will be very consistent even if the voltage varies, and no external choke resistors are required making the design slim. Power the whole thing with 5VDC (4-7V works) and you're ready to rock.There is a single data line with a very timing-specific protocol. Since the protocol is very sensitive to timing, it requires a real-time microconroller such as an AVR, Arduino, PIC, mbed, etc. It cannot be used with a Linux-based microcomputer or interpreted microcontroller such as the netduino or Basic Stamp. Our wonderfully-written Neopixel library for Arduino supports these pixels! As it requires hand-tuned assembly it is only for AVR cores but others may have ported this chip driver code so please google around. An 8MHz or faster processor is required.Comes as a single ring with 16 individually addressable RGB LEDs assembled and tested.

Make your own little LED strip arrangement with this stick of NeoPixel LEDs. We crammed 8 of the tiny 5050 (5mm x 5mm) smart RGB LEDs onto a PCB with mounting holes and a chainable design. Use only one microcontroller pin to control as many as you can chain together! Each LED is addressable as the driver chip is inside the LED. Each one has ~18mA constant current drive so the color will be very consistent even if the voltage varies, and no external choke resistors are required making the design slim. Power the whole thing with 5VDC (4-7V works) and you're ready to rock.The LEDs are 'chainable' by connecting the output of one stick into the input of another - see the photo above. There is a single data line with a very timing-specific protocol. Since the protocol is very sensitive to timing, it requires a real-time microconroller such as an AVR, Arduino, PIC, mbed, etc. It cannot be used with a Linux-based microcomputer or interpreted microcontroller such as the netduino or Basic Stamp. Our wonderfully-written Neopixel library for Arduino supports these pixels! As it requires hand-tuned assembly it is only for AVR cores but others may have ported this chip driver code so please google around. An 8MHz or faster processor is required.Comes as a single stick with 8 individually addressable RGB LEDs assembled and tested.Our detailed NeoPixel Uberguide has everything you need to use NeoPixels in any shape and size. Including ready-to-go library & example code for the Arduino UNO/Duemilanove/Diecimila, Flora/Micro/Leonardo, Trinket/Gemma, Arduino Due & Arduino Mega/ADK (all versions)

NeoPixel Stick - 8 x 5050 RGB LED with Integrated Drivers (6:15)

Make your own smart LED arrangement with the same integrated LED that is used in our NeoPixel strip and pixels. This tiny 5050 (5mm x 5mm) RGB LED is fairly easy to solder and is the most compact way possible to integrate multiple bright LEDs to a design. The driver chip is inside the LED and has ~18mA constant current drive so the color will be very consistent even if the voltage varies, and no external choke resistors are required making your design minimal. Power the whole thing with 5VDC and you're ready to rock.This is the 4 pin LED chip version, not 6. It is code compatible and the same over-all shape and functionality but not the same pinout so you cannot use these to replace an 'S chip. If you are designing a new PCB we suggest going with the B, since it has built in polarity protection. Other than that, B and S are the same brightness, and use the exact same code interface.The LEDs are 'chainable' by connecting the output of one chip into the input of another - see the datasheet for diagrams and pinouts. To allow the entire chip to be integrated into a 6-pin package, there is a single data line with a very timing-specific protocol. Since the protocol is very sensitive to timing, it requires a real-time microconroller such as an AVR, Arduino, PIC, mbed, etc. It cannot be used with a Linux-based microcomputer or interpreted microcontroller such as the netduino or Basic Stamp. The LEDs basically have a WS2811 inside, but fixed at the 800KHz 'high speed' setting. Our wonderfully-written Neopixel library for Arduino supports these pixels! As it requires hand-tuned assembly it is only for AVR cores but others may have ported this chip driver code so please google around. An 8MHz or faster processor is required.

These raw LEDs are cut from a reel and/or might be loose. They may not suitable for pick & place + reflow. We recommend these for careful hand soldering only! Comes in a package with 100 individual LEDs. We have a ready-to-go component for this in the Adafruit EAGLE library

For those of us who are maybe a little tired of rainbows, we now have 'smart LEDs' in monochrome! Make your own smart Cool White LED arrangement with the same integrated LED dr that is used in our new fancy DotStar strips.  Unlit, the color resembles a yellow Starburst. Lit up these are insanely bright (like ow my eye hurts) and can be controlled with 24 bit high-frequency PWM. The phosphor helps diffuse the 3 white dies inside together for a very bright but consistant light, compared to what you get by trying to mix RGB to make white (which never quite looks right)

This tiny 5050 (5mm x 5mm) SMD LED is fairly easy to solder and is the most compact way possible to integrate multiple bright LEDs to a design. If you want to prototype with these, we recommend our 5050-size LED breakout PCBs, solder them on for a breadboard-friendly package

They're also a great upgrade for people who have loved and used NeoPixels for a few years but want to use the same kind of technology for monochromatic lighting. DotStar LEDs use generic 2-wire SPI, so you can push data much faster than with the NeoPixel 800 KHz protocol and there's no specific timing required. They also have much higher PWM refresh rates, so you can do Persistence-of-Vision (POV) and have less flickering, particularly at low brightness levels.

Like NeoPixels, DotStar LEDs are 5050-sized LEDs with an embedded microcontroller inside the LED. You can set the brightness of each of 3 individual cool white dies epoxied into the case. Each LED acts like a shift register, reading incoming data on the input pins, and then shifting the previous data out on the output pin. By sending a long string of data, you can control an infinite number of LEDs, just tack on more or disconnect unwanted LEDs at the end. The PWM is built into each LED-chip so once you set the brightness you can stop talking to the strip and it will continue to PWM all the LEDs for you.

Another nice thing about DotStars is their high PWM rate. You only have to set the brightness data for each pixel LED once, and then the LED+built-in-chip will handle the PWMing. On NeoPixels, this PWM rate happens 400 Hz, which works well but is noticably at lower brightnesses and if the strip is moving in any way.  DotStars have a 20 KHz PWM rate, so even when moving the LED around, you won't see the pixelation, the blending is very smooth.

Comes in a package with 10 individual LEDs.

We have a tutorial showing wiring, power usage calculations, example code for usage, etc. for DotStars Please check it out! Please note that the tutorial and code talk about RGB, but of course, this LED is just WWW, three individual white LEDs instead.

For those of us who are maybe a little tired of rainbows, we now have 'smart LEDs' in monochrome! Make your own smart Cool White LED arrangement with the same integrated LED driver that is used in our NeoPixel LED strips.  Unlit, the color resembles a yellow Starburst. Lit up these are insanely bright (like ow my eye hurts) and can be controlled with 24 bit high-frequency PWM. The phosphor helps diffuse the 3 white dies inside together for a very bright but consistant light, compared to what you get by trying to mix RGB to make white (which never quite looks right)

This tiny 5050 (5mm x 5mm) SMD LED is fairly easy to solder and is the most compact way possible to integrate multiple bright LEDs to a design. If you want to prototype with these, we recommend our 5050-size LED breakout PCBs, solder them on for a breadboard-friendly package

NeoPixel LEDs use 800 KHz protocol so specific timing is required. On NeoPixels, the PWM rate is 400 Hz, which works well but is noticable if the LED is moving. In comparison, DotStars have a 20 KHz PWM rate, so even when moving the LED around, you won't see the pixelation, the blending is very smooth. (we recommend DotStars if you can use them!)

NeoPixels are 5050-sized LEDs with an embedded microcontroller inside the LED. You can set the brightness of each of 3 individual cool white dies epoxied into the case. Each LED acts like a shift register, reading incoming data on the input pins, and then shifting the previous data out on the output pin. By sending a long string of data, you can control an infinite number of LEDs, just tack on more or disconnect unwanted LEDs at the end. The PWM is built into each LED-chip so once you set the brightness you can stop talking to the strip and it will continue to PWM all the LEDs for you.

Comes in a package with 10 individual LEDs.

We have a tutorial showing wiring, power usage calculations, example code for usage, etc. for NeoPixel Please check it out! Please note that the tutorial and code talk about RGB, but of course, this LED is just WWW, three individual white LEDs instead.

For those of us who are maybe a little tired of rainbows, we now have 'smart LEDs' in monochrome! Make your own smart Warm White LED arrangement with the same integrated LED driver that is used in our new fancy DotStar strips.  Unlit, the color resembles an egg yolk. Lit up these are insanely bright (like ow my eye hurts) and can be controlled with 24 bit high-frequency PWM. The phosphor helps diffuse the 3 white dies inside together for a very bright but consistant light, compared to what you get by trying to mix RGB to make white (which never quite looks right)

This tiny 5050 (5mm x 5mm) SMD LED is fairly easy to solder and is the most compact way possible to integrate multiple bright LEDs to a design. If you want to prototype with these, we recommend our 5050-size LED breakout PCBs, solder them on for a breadboard-friendly package

They're also a great upgrade for people who have loved and used NeoPixels for a few years but want to use the same kind of technology for monochromatic lighting. DotStar LEDs use generic 2-wire SPI, so you can push data much faster than with the NeoPixel 800 KHz protocol and there's no specific timing required. They also have much higher PWM refresh rates, so you can do Persistence-of-Vision (POV) and have less flickering, particularly at low brightness levels.

Like NeoPixels, DotStar LEDs are 5050-sized LEDs with an embedded microcontroller inside the LED. You can set the brightness of each of 3 individual cool white dies epoxied into the case. Each LED acts like a shift register, reading incoming data on the input pins, and then shifting the previous data out on the output pin. By sending a long string of data, you can control an infinite number of LEDs, just tack on more or disconnect unwanted LEDs at the end. The PWM is built into each LED-chip so once you set the brightness you can stop talking to the strip and it will continue to PWM all the LEDs for you.

Another nice thing about DotStars is their high PWM rate. You only have to set the brightness data for each pixel LED once, and then the LED+built-in-chip will handle the PWMing. On NeoPixels, this PWM rate happens 400 Hz, which works well but is noticably at lower brightnesses and if the strip is moving in any way.  DotStars have a 20 KHz PWM rate, so even when moving the LED around, you won't see the pixelation, the blending is very smooth.

Comes in a package with 10 individual LEDs.

We have a tutorial showing wiring, power usage calculations, example code for usage, etc. for DotStars Please check it out! Please note that the tutorial and code talk about RGB, but of course, this LED is just WWW, three individual white LEDs instead.

So much power and light from such a small package. This 5 pack of “Cool” white 3 Watt aluminum backed PCBs is sure to shed a lot of light on any project you add it to. These LEDs act as any other LED except these little guys require much more power while delivering a light as intense of a thousand suns going super nova (this is an exaggeration but you know what we mean)!

Each LED in the pack sits upon an aluminum backed PCB to help with heat dissipation and emits a cool white light. Additionally, each LED requires a forward voltage of 3.2-3.8V at 750mA.

Note: We like to joke around about super novas and all, but seriously, don’t look directly into the LED.

Features

Forward Voltage: 3.2-3.8V

Forward Current: 750mA

Viewing angle: 125±5 Degrees

Luminous Intensity: 160-240LM

Temperature Color: 6000-7000K

So much power and light from such a small package. This 5 pack of red 3 Watt aluminum backed PCBs is sure to shed a lot of light on any project you add it to. These LEDs act as any other LED except these little guys require much more power while delivering a light as intense of a thousand suns going super nova (this is an exaggeration but you know what we mean)!

Each LED in the pack sits upon an aluminum backed PCB to help with heat dissipation and emits a vibrant red light. Additionally, each LED requires a forward voltage of 2.0-2.8V at 750mA.

Note: We like to joke around about super novas and all, but seriously, don’t look directly into the LED.

Features

Forward Voltage: 2.0-2.8V

Forward Current: 750mA

Viewing angle: 125±5 Degrees

Luminous Intensity: 75-105LM

Wavelength: 620-630nm

With a slip ring assembly, your electronics can now twist and turn safely. Add wheel encoders, 360 degree sensors, rotating LEDs, rotors and more! We've seen a lot of people DIY slip ring's out of desperation but no longer, simply pick up one of these to solve any rotation needs you have.Inside the miniature plastic tube is a gold plated slip ring for 12 wires. There are twelve color coded wire sets made of 28 AWG and no matter how you twist the assembly, they will remain in continuity. Each of the wire sets can carry up to 2A at up to 240VAC or 240VDC. This model is the tiniest slip ring you can get, a mere 20mm long, 12mm diameter. Rated to rotate up to 300 RPM (but you can probably go faster if you don't mind a reduced life and/or noise).

12-wire slip rings (3:42)

By popular demand, we now have these buttons with a full color RGB LED ring light! These chrome-plated metal buttons are rugged, but certainly not lacking in flair. Simply drill a 16mm hole into any material up to 1/4" thick and you can fit these in place – there's even a rubber gasket to keep water out of the enclosure. On the front of the button is a flat metal actuator, surrounded by a plastic RGB LED ring. On the back there are two gold contacts for the button and 4 for the RGB LED ring (one anode and 3 cathodes for each red, green, and blue). Power the anode at 3-6V and light up the red, green, and blue LEDs by pulling their designated contacts to ground as you desire – there's a built in resistor! If you want to use this with a higher voltage, say 12V or 24V, simply add a 1K ohm resistor in series with the LED cathodes to keep the LED current at around 20mA. You can PWM the RGB pins to make any color you like.This button is a momentary push button, when you press it the 'normally-open' contact shorts to the common contact. When you release it, the contacts open up again.The switch and LED are electrically separated, so to change the color, use a microcontroller to both read the contact pins and toggle the color control pins.

These chrome-plated metal buttons are rugged and look real good while doing it! Simply drill a 16mm hole into any material up to 1/2" thick and you can fit these in place, there's even a rubber gasket to keep water out of the enclosure. On the front of the button is a flat metal actuator, surrounded by a white plastic LED ring. On the back there are 3 contacts for the button (common, normally-open and normally-closed) and 2 for the white LED ring (+ and -). Connect 3 to 6V to the LED to have it light up nicely, there's a built in resistor! If you want to use this with a higher voltage, say 12V or 24V, simply add a 470 ohm resistor in series with the LED connection to keep the LED current at around 20mA.This button is an on/off switch button, when you press it the 'normally-open' contact shorts to the common contact and the button stays 'pressed'. When you press it a second time, the button springs open, and the contacts open up again.The switch and LED are separated, so you could wire it to turn on when pressed or vice versa or whatever you wish! Check the tech details for information!

These chrome-plated metal buttons are rugged and look real good while doing it! Simply drill a 16mm hole into any material up to 1/2" thick and you can fit these in place, there's even a rubber gasket to keep water out of the enclosure. On the front of the button is a flat metal actuator, surrounded by a red plastic LED ring. On the back there are 3 contacts for the button (common, normally-open and normally-closed) and 2 for the red LED ring (+ and -). Connect 3 to 6V to the LED to have it light up nicely, there's a built in resistor! If you want to use this with a higher voltage, say 12V or 24V, simply add a 470 ohm resistor in series with the LED connection to keep the LED current at around 20mA.This button is a momentary push button, when you press it the 'normally-open' contact shorts to the common contact. When you release it, the contacts open up again.The switch and LED are separated, so you could wire it to turn on when pressed or vice versa or whatever you wish! Check the tech details for information!

These chrome-plated metal buttons are rugged and look real good while doing it! Simply drill a 16mm hole into any material up to 1/2" thick and you can fit these in place, there's even a rubber gasket to keep water out of the enclosure. On the front of the button is a flat metal actuator, surrounded by a blue plastic LED ring. On the back there are 3 contacts for the button (common, normally-open and normally-closed) and 2 for the blue LED ring (+ and -). Connect 3 to 6V to the LED to have it light up nicely, there's a built in resistor! If you want to use this with a higher voltage, say 12V or 24V, simply add a 470 ohm resistor in series with the LED connection to keep the LED current at around 20mA.This button is an on/off switch button, when you press it the 'normally-open' contact shorts to the common contact and the button stays 'pressed'. When you press it a second time, the button springs open, and the contacts open up again.The switch and LED are separated, so you could wire it to turn on when pressed or vice versa or whatever you wish! Check the tech details for information!

These chrome-plated metal buttons are rugged and look real good while doing it! Simply drill a 16mm hole into any material up to 1/2" thick and you can fit these in place, there's even a rubber gasket to keep water out of the enclosure. On the front of the button is a flat metal actuator, surrounded by a red plastic LED ring. On the back there are 3 contacts for the button (common, normally-open and normally-closed) and 2 for the red LED ring (+ and -). Connect 3 to 6V to the LED to have it light up nicely, there's a built in resistor! If you want to use this with a higher voltage, say 12V or 24V, simply add a 470 ohm resistor in series with the LED connection to keep the LED current at around 20mA.This button is an on/off switch button, when you press it the 'normally-open' contact shorts to the common contact and the button stays 'pressed'. When you press it a second time, the button springs open, and the contacts open up again.The switch and LED are separated, so you could wire it to turn on when pressed or vice versa or whatever you wish! Check the tech details for information!

A button is a button, and an LED is a LED, but this LED illuminated button is a lovely combination of both! It's a medium sized button, large enough to press easily but not too big that it gets in the way of your project panel. It has a built in LED that can be controlled separately from the switch action - either to indicate or just to look good.The body is a black plastic with the LED built inside. There are two contacts for the button and two contacts for the LED, one marked + and one -. The forward voltage of the LED is about 2.2V so connect a 220 to 1000 ohm resistor in series just as you would with any other LED to your 3V or higher power supply.This particular button has a red body and LED and is momentary, normally open. The two switch contacts are not connected normally. When you push the button they will temporarily connect until the button is released. The LED is separated from the button, so you can make it light up when pressed, light up when not pressed, always lit, etc.

16mm Illuminated Pushbuttons (7:54)

A button is a button, and a switch is a switch, but these translucent arcade buttons are in a class of their own. They're the same size as common arcade controls (often referred to as 30mm diameter) but have some nice things going for them that justify the extra dollar.First, they look fantastic, all 6 colors have a crystal translucent glossy look. Although they do not have LEDs built in, we're confident that sticking a diffused LED into the body would make it light up very nicely. They are also shorter than cheap arcade controls, and snap into place, so you only need 1.5" of depth (1.25" if you bend the contacts over). The button action is smooth, without a strong click, yet you can definitely feel when the button is pressed. A tiny micro-switch is pre-installed, with gold plated contacts.

A button is a button, and a switch is a switch, but this LED illuminated arcade buttons is in a class of its own. It's similar in size to an arcade button (and will fit in holes drilled for 'standard' 30mm buttons) but has a built in LED that can be controlled separately from the switch action - either to indicate or just to look good.The body is a black plastic, and a lamp holder fits inside. These were originally designed for 'incandescent' lamps but is easy to use with an LED, just wrap the legs around the holder as shown. It comes with a clear blue LED but honestly, we suggest finding a diffused LED to use instead, with a wide illumination since this clear one doesn't fill the square as nicely as it could. (The button factory didn't have diffused LEDs available). You can even disassemble the button itself and slip an image under the clear cover for backlighting.The button comes with a normally-open micro-switch. Once you have put in the LED you like, just snap in the micro-switch. You can always remove it later to change out the LED color. The micro-switch is fairly clicky, so you will hear and feel it when it actuates.

A button is a button, and a switch is a switch, but these translucent arcade buttons are in a class of their own. They're the same size as common arcade controls (often referred to as 30mm diameter) but have some nice things going for them that justify the extra dollar.First, they look fantastic, all 6 colors have a crystal translucent glossy look. Although they do not have LEDs built in, we're confident that sticking a diffused LED into the body would make it light up very nicely. They are also shorter than cheap arcade controls, and snap into place, so you only need 1.5" of depth (1.25" if you bend the contacts over). The button action is smooth, without a strong click, yet you can definitely feel when the button is pressed. A tiny micro-switch is pre-installed, with gold plated contacts.

A button is a button, and a switch is a switch, but these translucent arcade buttons are in a class of their own. They're the same size as common arcade controls (often referred to as 30mm diameter) but have some nice things going for them that justify the extra dollar.First, they look fantastic, all 6 colors have a crystal translucent glossy look. Although they do not have LEDs built in, we're confident that sticking a diffused LED into the body would make it light up very nicely. They are also shorter than cheap arcade controls, and snap into place, so you only need 1.5" of depth (1.25" if you bend the contacts over). The button action is smooth, without a strong click, yet you can definitely feel when the button is pressed. A tiny micro-switch is pre-installed, with gold plated contacts.

A button is a button, and a switch is a switch, but these translucent arcade buttons are in a class of their own. They're the same size as common arcade controls (often referred to as 30mm diameter) but have some nice things going for them that justify the extra dollar.First, they look fantastic, all 6 colors have a crystal translucent glossy look. Although they do not have LEDs built in, we're confident that sticking a diffused LED into the body would make it light up very nicely. They are also shorter than cheap arcade controls, and snap into place, so you only need 1.5" of depth (1.25" if you bend the contacts over). The button action is smooth, without a strong click, yet you can definitely feel when the button is pressed. A tiny micro-switch is pre-installed, with gold plated contacts.

The Parallax ColorPAL combines an RGB LED, a light sensor, and a microcontroller to make a color sensor that can also be used as an ambient light detector and a color generator. Readings are reported via a 1-wire asynchronous serial interface.

ColorPAL side view.

The ColorPAL from Parallax is a miniature color and light sensor that can double as a color generator with its RGB LED. When sensing color, the ColorPAL uses its LED to illuminate a sample one color component at a time while measuring the light reflected back with a broad-spectrum light-to-voltage converter. The amount of light reflected from the sample under illumination from each red, green, and blue LED can be used to determine the sample’s color. For the ColorPAL to detect the color of a subject, the subject must be reflective and non-fluorescent. The color of objects that emit light (e.g. LEDs) cannot be detected.

Detects a wide range of colors and outputs data as 10-bit RGB (Red/Green/Blue) components.

Detects broad-spectrum ambient light with sensitivity down to 44µW/cm2 per lsb.

Generates 24-bit color using onboard RGB LED.

Plugs into servo headers or cables or solderless breadboards.

Single-pin interface uses a simple serial protocol to define and initiate color detection and generation.

Color detection and generation details handled by onboard microcontroller.

Onboard EEPROM for saving custom color detection and generation programs.

Autorun feature permits running a pre-designated EEPROM program with only a power supply.

Power requirements: 5.0 VDC

Communication: 1-wire serial (asynchronous, non-inverted, open-drain serial protocol) with automatic baud rate detection from 2400 – 7200 bps

Dimensions: 1.72 × 0.90 × 0.65 in (44 × 23 × 17 mm)

Communication with the ColorPAL takes place using serial I/O, transmitting and receiving at between 2400 and 7200 baud, using a non-inverted, open-drain protocol. The ColorPAL includes a pull-up resistor to Vdd, so you do not need to apply one externally. Because of the open-drain protocol, the pin used to communicate with the ColorPAL should always be configured as an input, except when being driven low. Also, when starting up, you should wait for this pin to be pulled high by the ColorPAL before trying to send it any commands. Please see the user’s manual (297k pdf) for more information.

People often buy this product together with:

Add some jazz & pizazz to your project with a color touchscreen LCD. This TFT display is big (2.8" diagonal) bright (4 white-LED backlight) and colorful! 240x320 pixels with individual RGB pixel control, this has way more resolution than a black and white 128x64 display. As a bonus, this display has a resistive touchscreen attached to it already, so you can detect finger presses anywhere on the screen. We also have a version of this display breakout with a capacitive touchscreen.

This display has a controller built into it with RAM buffering, so that almost no work is done by the microcontroller. The display can be used in two modes: 8-bit and SPI. For 8-bit mode, you'll need 8 digital data lines and 4 or 5 digital control lines to read and write to the display (12 lines total). SPI mode requires only 5 pins total (SPI data in, data out, clock, select, and d/c) but is slower than 8-bit mode. In addition, 4 pins are required for the touch screen (2 digital, 2 analog) or you can purchase and use our resistive touchscreen controller (not included) to use I2C or SPI

We wrapped up this display into an easy-to-use breakout board, with SPI connections on one end and 8-bit on the other. Both are 3-5V compliant with high-speed level shifters so you can use with any microcontroller. If you're going with SPI mode, you can also take advantage of the onboard MicroSD card socket to display images. (microSD card not included, but any will work)

Of course, we wouldn't just leave you with a datasheet and a "good luck!". For 8-bit interface fans we've written a full open source graphics library that can draw pixels, lines, rectangles, circles, text, and more. For SPI users, we have a library as well, its separate from the 8-bit library since both versions are heavily optimized. We also have a touch screen library that detects x, y and z (pressure) and example code to demonstrate all of it.

Follow our step by step guide for wiring, code and drawing. You'll be running in 15 minutes

If you are using an Arduino-shaped microcontroller, check out our TFT shield version of this same display, with SPI control and a touch screen controller as well

The 1.3" 168x144 SHARP Memory LCD display is a cross between an eInk (e-paper) display and an LCD. It has the ultra-low power usage of eInk and the fast-refresh rates of an LCD. This model has a gray background, and pixels show up as black-on-gray for a nice e-reader type display. It does not have a backlight, but it is daylight readable. For dark/night reading you may need to illuminate the LCD area with external LEDs.The bare display is 3V powered and 3V logic, so we placed it on a fully assembled & tested breakout board with a 3V regulator and level shifting circuitry. Now you can use it safely with 3 or 5V power and logic. The bare display slots into a ZIF socket on board and we use a piece of double-sided tape to adhere it onto one side. There are four mounting holes so you can easily attach it to a box.The display is 'write only' which means that it only needs 3 pins to send data. However, the downside of a write-only display is that the entire 168x144 bits (3 KB) must be buffered by the microcontroller driver. That means you cannot use this with an ATmega328 (e.g. Arduino UNO) or ATmega32u4 (Feather 32u4, etc). You must use a high-RAM chip such as ATSAMD21 (Feather M0), Teensy 3, ESP8266, ESP32, etc. On those chips, this display works great and looks wonderful.

Check our our detailed guide for wiring diagrams, schematics, libraries, code, Fritzing objects, etc!

One can never have enough socks, or USB ports. Add some more USB capability to your Raspberry Pi Zero with the Zero4U!

This is a 4-port USB hub for Raspberry Pi Zero, and it can be mounted back-to-back onto a Pi Zero. The 4 pogo pins on the back will connect the PP1, PP6, PP22 and PP23 testing pads on your Raspberry Pi Zero – no soldering required!

This item can only work with the Zero W if a ferrite ring is installed!

The USB hub will take power directly from your Pi Zero, so you don’t need to power the USB hub separately. However you can use the JST XH2.54 connector on board as an alternative power input port. The blue onboard LED is the power indicator, and will light up when power is connected. Each USB port uses a dedicated white LED as a transaction indicator, and a dedicated electrolytic capacitor to help stabilize the output voltage.

If you use this USB hub with other types of computers, you can use a USB cable (not included) to connect the onboard mini-USB port to the up-stream USB port.

Kit includes:

4-port USB hub board x 1

Plastic spacer x 4

M2.5 plastic screw x 4

M2.5 plastic nut x 4

Note: This version of Zero4U only works with the Raspberry Pi Zero v1.3 (with camera connector).

Note: As of 3/29/2017, this ships with a small Ferrite ring in each Zero4U package, in order to support the newly released Raspberry Pi Zero W. The user can put that Ferrite ring on the pogo pins to avoid the interference from the on-board antenna.

PiJack is a HAT (yes, a proper HAT, not a pHAT!) add-on board for the Raspberry Pi Zero mini computer that makes connecting your Pi Zero to the Internet via Ethernet super simple. If you're fed up with flaky WiFi and want your Pi Zero to be online all the time, then this HAT is for you!

PiJack is a neat little board with an Ethernet controller and standard RJ45 connector so you can hook your Pi up to your home or office network using standard Ethernet cables. PiJack is ready to go – there's no special software or drivers to install. It works right out of the box with Raspbian – simply attach PiJack to your Pi's GPIO header and plug it in!

Features:

10Mbps Ethernet connection

Two blinky LEDs for connection status

HAT-standard-compliant EEPROM makes setup automatic, works straight away with Raspbian!

Uses the Pi Zero's GPIO pins, your USB connector is still free for something else!

Note: Pi Zero and Ethernet cable not included!

PiJack is well engineered and uses high quality components and connectors (that won't snap off the first time you use it!). PiJack is built in the EU, and every board is tested to make sure it'll work for you first time.

The Pimoroni Speaker pHAT crams an I2S DAC and mono amplifier, a tiny 8Ω 2W speaker, and a 10 LED bar graph all onto one teeny little pHAT. It's the neatest way to add audio to your Pi project, and its beautiful artwork evokes an 80s boombox!

Pimoroni isn't claiming audiophile sound quality, but it's perfect for fun little projects where you want to add sound output – speech, notification sounds, or light music, for example.

Why not combine it with a little USB microphone to make a tiny voice-activated assistant in the style of Amazon's Echo? Or set up a simple Flask API and send audio notifications to it from IFTTT with a simple HTTP request.

It comes as a kit, so you'll have to solder on the female 40 pin header, and screw and solder the speaker on. Check out Pimoroni's assembly guide for more details.

Features:

I2S audio DAC with 3W mono amplifier (MAX98357A)

Default output of 0.45W/26.5dB

8Ω 2W Mylar speaker

Routed holes to channel sound

10 bright white bar graph LEDs

SN3218 LED driver chip

Compatible with Raspberry Pi 3, 2, B+, A+, and Zero

Female header and speaker require soldering (includes a piece of bare wire to solder the speaker)

Kit includes:

Speaker pHAT

8Ω 2W Mylar speaker

2x20 pin female header

5cm 24AWG bare wire

4x M2x8 black nylon bolts

8x M2 black nylon nuts

Note: Pi Zero not included!

Looking for an unashamedly old school LED matrix display board? Lookie here! The Pimoroni Micro Dot pHAT is made up of six red LED matrices, each 5x7 pixels (for an effective display area of 30x7) plus a decimal point, using the beautiful little Lite-On LTP-305 matrices.

Perfect for building a retro scrolling message display, a tiny 30-band spectrum analyzer, or a retro clock. Far out!

As with the other pHATs, it works with all of the 40-pin Raspberry Pi variants - 3/2/B+/A+/Zero - but using it with the Pi Zero makes for a super-tiny package.

Features:

3x onboard IS31FL3730 LED matrix driver chips

Drives up to 6 x LTP-305 red LED matrices

Up to 30x7 pixels (5x7 per matrix plus a decimal point)

Kit includes:

Assembled Micro Dot pHAT PCB

2x20 0.1" female GPIO header

6 Red LTP-305 LED modules

Micro Dot pHAT also works well with other pHATs and HATs. You could use it in combination with pHAT DAC to display the audio spectrum, or with Enviro pHAT to display its temperature, pressure and light readings. Give it a try!

Note: These pHAT boards require you to solder on the headers and LTP-305 modules (through-hole components). Works with any 40-pin Raspberry Pi variant.

The SparkFun Touch Potentiometer, or Touch Pot for short, is an intelligent linear capacitive touch sensor that implements potentiometer functionality with 256 positions. It can operate as a peripheral to a computer or embedded microcontroller or in a stand-alone capacity. The Touch Potentiometer provides both a dual-channel analog and PWM output for direct control of other circuitry. Configurable analog and PWM transfer functions support a wide variety of applications such as volume control and LED dimming.

The Touch Potentiometer is controlled by a Microchip PIC16F1829 8-bit micro-controller that provides the host interface, LED control, capacitive sense and peripheral control functions. A built-in low-dropout voltage regulator allows operation over a range of input voltages up to 12V and breadboard friendly connectors make it easy to play with. A desktop application has been created by our collaborator, Dan Julio, that communicates with the Touch Pot over a serial connection. From this utility app you can change configuration settings, alter LED behavior, calibrate the capacitive touch sensor, view current readings in jabber mode, and much more.

Note: This product is a collaboration with danjuliodesigns. A portion of each sales goes back to them for product support and continued development.

Get Started with the SparkFun Touch Potentiometer Guide

Features

Dual host interfaces: Logic-level serial and I2CTM

Dual 8-bit 20 k-ohm 3-terminal digitally controlled variable resistor outputs

PWM output

8 LED display with multiple display modes and intensity levels

Option for interpolated (soft) changes between touches

Configurable touch sensor parameters for a variety of PCB covers

Easily configurable I2C address to allow multiple devices on one bus

Configurable linear or non-linear PWM transfer function

Configurable linear or simulated logarithmic variable resistor transfer function

Variable resistor supports single- or dual-supply operation

Simple register interface with jabber option

Programmable power-on default operation

Built-in calibration procedure

User-accessible EEPROM data storage

Built-in 5V LDO voltage regulator

Through-hole and SMT connectors

This is a very simple board that takes a 6-12V input voltage and outputs a selectable 5V or 3.3V regulated voltage. All headers are 0.1" pitch for simple insertion into a breadboard.

Input power can be supplied to either the DC barrel jack or the two pin header labeled + and -. Output power is supplied to the pins labeled GND and VCC. Board has both an On/Off switch and a voltage select switch (3.3V/5V).

The two sets of four GND and VCC holes are spaced such that when connected to our Basic Breadboard both power busses will be powered.

Note: Headers are not supplied. You will need to supply your own headers to connect this board to a breadboard. Check below for some breakaway header strips.

Features

6-12V input voltage via barrel jack or 2-pin header

3.3V or 5V regulated output voltage

800mA Operating Current

ON/OFF switch

Output voltage select switch

Power status LED

PTC fuse protected power

5.5x2.1mm center positive barrel jack

2.15x0.65"

The smallest and easiest to use serial conversion circuit on the market! This board has one purpose in life - to convert RS232 to TTL and vice versa (TX and RX). This will allow a microcontroller to communicate with a computer. Shifter SMD is powered from the target application and can run at any voltage! That’s right - power the board at 5V and the unit will convert RS232 to 5V TTL. Power the board at 2.8V and the Shifter board will convert RS232 to 2.8V CMOS TTL. Includes two indicator LEDs for TX and RX. Runs from 300bps up to 115200bps.

This version comes with no DB9 connector attached. Useful for field installations and projects where RS232 serial is coming from something other than a DB9 cable.

Features

1.2x1.1"

This is the newest revision of our FTDI Basic. We now use a SMD 6-pin header on the bottom, which makes it smaller and more compact. Functionality has remained the same.

This is a basic breakout board for the FTDI FT232RL USB to serial IC. The pinout of this board matches the FTDI cable to work with official Arduino and cloned 5V Arduino boards. It can also be used for general serial applications. The major difference with this board is that it brings out the DTR pin as opposed to the RTS pin of the FTDI cable. The DTR pin allows an Arduino target to auto-reset when a new Sketch is downloaded. This is a really nice feature to have and allows a sketch to be downloaded without having to hit the reset button. This board will auto reset any Arduino board that has the reset pin brought out to a 6-pin connector.

The pins labeled BLK and GRN correspond to the colored wires on the FTDI cable. The black wire on the FTDI cable is GND, green is CTS. Use these BLK and GRN pins to align the FTDI basic board with your Arduino target.

This board has TX and RX LEDs that make it a bit better to use over the FTDI cable. You can actually see serial traffic on the LEDs to verify if the board is working.

This board was designed to decrease the cost of Arduino development and increase ease of use (the auto-reset feature rocks!). Our Arduino Pro boards and LilyPads use this type of connector.

One of the nice features of this board is a jumper on the back of the board that allows the board to be configured to either 3.3V or 5V (both power output and IO level). This board ship default to 5V, but you can cut the default trace and add a solder jumper if you need to switch to 3.3V.

Note: We know a lot of you prefer microUSB over miniUSB. Never fear, we’ve got you covered! Check out our FT231X Breakout for your micro FTDI needs!

This is the newest revision of our FTDI Basic. We now use a SMD 6-pin header on the bottom, which makes it smaller and more compact. Functionality has remained the same.

This is a basic breakout board for the FTDI FT232RL USB to serial IC. The pinout of this board matches the FTDI cable to work with official Arduino and cloned 3.3V Arduino boards. It can also be used for general serial applications. The major difference with this board is that it brings out the DTR pin as opposed to the RTS pin of the FTDI cable. The DTR pin allows an Arduino target to auto-reset when a new Sketch is downloaded. This is a really nice feature to have and allows a sketch to be downloaded without having to hit the reset button. This board will auto reset any Arduino board that has the reset pin brought out to a 6-pin connector.

The pins labeled BLK and GRN correspond to the colored wires on the FTDI cable. The black wire on the FTDI cable is GND, green is DTR. Use these BLK and GRN pins to align the FTDI basic board with your Arduino target.

There are pros and cons to the FTDI Cable vs the FTDI Basic. This board has TX and RX LEDs that allow you to actually see serial traffic on the LEDs to verify if the board is working, but this board requires a Mini-B cable. The FTDI Cable is well protected against the elements, but is large and cannot be embedded into a project as easily. The FTDI Basic uses DTR to cause a hardware reset where the FTDI cable uses the RTS signal.

This board was designed to decrease the cost of Arduino development and increase ease of use (the auto-reset feature rocks!). Our Arduino Pro and LilyPad boards use this type of connector.

Note: We know a lot of you prefer microUSB over miniUSB. Never fear, we’ve got you covered! Check out our FT231X Breakout for your micro FTDI needs!

If you need to charge LiPo batteries, this simple charger will do just that, and do it fast! The SparkFun USB LiPo Charger is a basic charging circuit that allows you to charge 3.7V LiPo cells at a rate of 500mA or 100mA. It is designed to charge single-cell Li-Ion or Li-Polymer batteries.

The board incorporates a charging circuit, status LED, selectable solder jumper for 500mA or 100mA charging current, external LED footprint, USB input, two pre-installed JST connectors for SYS OUT and BATT IN, and (back by popular demand) a barrel jack connector.

There is also a ‘SYS OUT’ with a pre-installed JST connector which allows you to connect the charging circuit directly to your project so you don’t need to disconnect the charger each time you want to use it.

The SparkFun OpenLog is an open source data logger that works over a simple serial connection and supports microSD cards up to 64GB. The OpenLog can store or “log” huge amounts of serial data and act as a black box of sorts to store all the serial data that your project generates, for scientific or debugging purposes.

The SparkFun OpenLog runs on an onboard ATmega328, running at 16MHz thanks to the onboard crystal. The OpenLog draws 6mA when recording a 512 byte buffer, but as that process takes a fraction of a second, the average current draw is closer to 5mA. Keep in mind though that if you are recording a constant data stream at 115200bps, you will approach that 6mA limit. All data logged by the OpenLog is stored on the microSD card that involve the features of 64MB to 64GB capacity and FAT16 or FAT32 file type.

Features

VCC Input: 3.3V-12V (Recommended 3.3V-5V)

Log to low-cost microSD FAT16/32 cards up to 64GB

Simple command interface

Configurable baud rates (up to 115200bps)

Preprogrammed ATmega328 and bootloader

Four SPI pogo pins

Two LEDs indicate writing status

2mA idle, 6mA at maximum recording rate

This is a breakout board for the WS2812B RGB LED. The WS2812B (or “NeoPixel”) is actually an RGB LED with a WS2811 built right into the LED! All the necessary pins are broken out to 0.1" spaced headers for easy bread-boarding. Several of these breakouts can even be chained together to form a display or an addressable string.

The SparkFun XBee Explorer Regulated takes care of the 3.3V regulation, signal conditioning, and basic activity indicators (Power, RSSI and DIN/DOUT activity LEDs). It translates the 5V serial signals to 3.3V so that you can connect a 5V (down to 3.3V) system to any XBee module. The board was conveniently designed to mate directly with the SparkFun Arduino Pro series of boards for wireless bootloading and USB based configuration.

This unit works with all XBee modules including the Series 1 and 2, standard and Pro versions. Plug an XBee into this breakout and you will have direct access to the serial and programming pins on the XBee unit and will be able to power the XBee with 5V.

This board comes fully populated with 3.3V regulator (5V max input), XBee socket, four status LEDs, and level shifting. In the latest revision the diode level shifter is replaced with a more robust MOSFET level shifter. This board does not include and XBee module. XBee modules sold below.

This is the FemtoBuck, a small-size single-output constant current LED driver. Each FemtoBuck has the capability to dim a single high-power channel of LEDs from 0-350mA at up to 36V while the dimming control can be either accessed via PWM or analog signal from 0-2.5V. This board is based off of the PicoBuck LED Driver, developed in collaboration with Ethan Zonca, except instead of blending three different LEDs on three different channels the FemtoBuck controls just one.

For the FemtoBuck, we’ve increased the voltage ratings on the parts to allow the input voltage to cover the full 36V range of the AL8805 driver. Since the FemtoBuck is a constant current driver, the current drawn from the supply will drop as supply voltage rises. In general, efficiency of the FemtoBuck is around 95%, depending on the input voltage. On board each FemtoBuck you will find two inputs for both power input and dimming control pins and an area to install a 3.5mm screw terminal. Finally at either side of the board you will find small indents or “ears” which will allow you to use a zip tie to secure the wires to the board after soldering them down. This version of the FemtoBuck is equipped with a small solder jumper that can be closed with a glob of solder to double the output current from 330mA to 660mA.

This tiny audio amplifier is based on the Texas Instruments TPA2005D1. Its efficient class-D operation means low heat and long battery life. It can drive an 8-Ohm speaker at up to 1.4 Watts; it won’t shake a stadium, but it will provide plenty of volume for your audio projects.

The fully-differential inputs are safe for floating audio signals such as from our MP3 Shield, and can also be connected to ground-referenced signals as well. A shutdown input is provided to save power when the amplifier is not being used, and a solder jumper and header are provided to connect a volume-control potentiometer (not included).

Note: The amplifier’s class-D design outputs a 250kHz PWM-like signal that is restored to an analog voltage in the speaker’s coil. This is what makes the amplifier so efficient, but because of the switching frequency, you should keep the amplifier as close to the speaker as possible to minimize possible interference.

Features

Extremely efficient class-D amplifier

1.4W into 8 Ohms

2.5V to 5.5V supply

Fully differential audio inputs, can be ground-referenced as well

Shutdown input with pullup and LED-follows-shutdown circuitry

PTH pads provided to change gain resistors if desired (see datasheet for details)

Solder jumper and header allow addition of a 10k volume control potentiometer (not included)

A Feather board without ambition is a Feather board without FeatherWings! This is the NeoPixel FeatherWing, a 4x8 RGB LED Add-on For All Feather Boards! Using our Feather Stacking Headers or Feather Female Headers you can connect a FeatherWing on top or bottom of your Feather board and make your Feather board strut like a peacock at a rave.

Put on your sunglasses before staring into these 32 configurable eye-blistering RGB LEDs. Arranged in a 4x8 matrix, each pixel is individually addressable. Only one pin is required to control all the LEDs. On the bottom we have jumpers for the DIN line to any of the I/O pins on a Feather.  Works with any/all of our Feathers! You can cut the default jumper trace and use any pin you like. (In particular, the default pin for Feather Huzzah ESP8266 must be moved, try pin #15!)

To make it easy to start, the LEDs are by default powered from either the USB power line or Battery power line, whichever is higher. Two Schottky diodes are used to switch between the two. This power arrangement is able to handle 1 Amp of constant current draw and maybe 2A peak, so not a good way to make a flashlight. It's better for colorful effects.

A level-up shifter converts the 3.3V logic of the Feather to the power line voltage. If, say, you need MORE blinky, you can chain these together. For the second Wing, connect the DIN connection to the first Wing's DOUT. Also connect a ground pin together and power with an independant 5V supply to keep from loading the power supply too much.

Check out our tutorial for pinouts, usage, and more!

Our detailed NeoPixel Uberguide has everything you need to use NeoPixels in any shape and size. Including ready-to-go library & example code for the Arduino UNO/Duemilanove/Diecimila, Flora/Micro/Leonardo, Trinket/Gemma, Arduino Due & Arduino Mega/ADK (all versions)

Check out our range of Feather boards here.

One segment? No way dude! 7-Segments for life!

A Feather board without ambition is a Feather board without FeatherWings! This is the Adafruit 4-Digit 7-Segment LED Matrix Display FeatherWing! This 7-segment FeatherWing backpack makes it really easy to add a 4-digit numeric display with decimal points and even 'second colon dots' for making a clock.

This version does not come with an LED matrix. Its also available in combo packs of Blue, Green, Red, White, or Yellow which we recommend since you'll know you have a working LED matrix. Not guaranteed to work with any other 7-segment modules.

7-Segment Matrices like these are 'multiplexed' - so to control all the seven-segment LEDs you need 14 pins. That's a lot of pins, and there are driver chips like the MAX7219 that can control a matrix for you but there's a lot of wiring to set up and they take up a ton of space. Here at Adafruit we feel your pain! After all, wouldn't it be awesome if you could control a matrix without tons of wiring? That's where these LED Matrix FeatherWings come in!

The LEDs themselves do not connect to the Feather. Instead, a matrix driver chip (HT16K33) does the multiplexing for you. The Feather simply sends i2c commands to the chip to tell it what LEDs to light up and it is handled for you. This takes a lot of the work and pin-requirements off the Feather. Since it uses only I2C for control, it works with any Feather and can share the I2C pins for other sensors or displays.

The product kit comes with:

A fully tested and assembled Adafruit 4-Digit 7-Segment LED Matrix Display FeatherWing

Two 16-pin headers

A bit of soldering is required to attach the matrix onto the FeatherWing but its very easy to do and only takes about 5 minutes!  Note: Feather board and seven-segment display are not included, but we have lots available in the shop.

Check out our detailed tutorial for pinouts, assembly, Arduino and CircuitPython usage, and more!

Display, elegantly, 012345678 or 9! Gaze, hypnotized, at ABCDEFGHIJKLM - well it can display the whole alphabet. You get the point.

A Feather board without ambition is a Feather board without FeatherWings! This is the Adafruit 0.56" 4-Digit 14-Segment Display FeatherWing! This 14-segment FeatherWing backpack makes it really easy to add a bright alphanumeric display that shows letters and numbers in a beautiful hue. It's super bright and designed for viewing from distances up to 23 feet (7 meters) away.

Works with any and all Feathers!

14-Segment Matrices like these are 'multiplexed' - so to control all the fourteen-segment LEDs you need 18 pins. That's a lot of pins, and there are driver chips like the MAX7219 that can control a matrix for you but there's a lot of wiring to set up and they take up a ton of space. Wouldn't it be awesome if you could control a matrix without tons of wiring? That's where these Alphanumeric LED Matrix FeatherWings come in, they make it really easy to add a 4-digit alphanumeric display with decimal points.

The LEDs themselves do not connect to the Feather. Instead, a matrix driver chip (HT16K33) does the multiplexing for you. The Feather simply sends i2c commands to the chip to tell it what LEDs to light up and it is handled for you. This takes a lot of the work and pin-requirements off the Feather. Since it uses only I2C for control, it works with any Feather and can share the I2C pins for other sensors or displays.

This product kit comes with:

A fully tested and assembled Adafruit 4-Digit 14-Segment Alphanumeric Display FeatherWing

Two sixteen pin headers

A bit of soldering is required to attach the matrix onto the FeatherWing but its very easy to do and only takes about 5 minutes!  Note: Feather board and 14-segment display are not included, but we have lots available in the shop.

Of course, in classic Adafruit fashion, we also have a detailed tutorial showing you how to solder, wire and control the display. We even wrote a very nice library for the backpacks in both Arduino & CircuitPython so you can get running in under half an hour, displaying letters or numbers on the 14-segment. If you've been eyeing matrix displays but hesitated because of the complexity, this is the solution you've been looking for.

A Feather board without ambition is a Feather board without FeatherWings!

This is the FeatherWing Proto - a prototyping add-on for all Feather boards. Using our Feather Stacking Headers or Feather Female Headers you can connect a FeatherWing on top or bottom of your Feather board and let the board take flight!

This has a duplicate breakout for each pin on a Feather, as well as a bunch of plain grid proto holes. For GND and 3.3V, we give you a strip of connected pads. There's plenty of room for buttons, indicator LEDs, or anything for your portable project. The FeatherWing Proto makes an ideal partner for any of our Feather boards.

Check out our range of Feather boards here.

You want to make a cool robot, maybe a hexapod walker, or maybe just a piece of art with a lot of moving parts. Or maybe you want to drive a lot of LEDs with precise PWM output. Then you realize that your microcontroller has a limited number of PWM outputs! What now? You could give up OR you could just get this handy PWM and Servo driver breakout.When we saw this chip, we quickly realized what an excellent add-on this would be. Using only two pins, control 16 free-running PWM outputs! You can even chain up 62 breakouts to control up to 992 PWM outputs (which we would really like to see since it would be glorious)

It's an i2c-controlled PWM driver with a built in clock. That means that, unlike the TLC5940 family, you do not need to continuously send it signal tying up your microcontroller, its completely free running!

It is 5V compliant, which means you can control it from a 3.3V microcontroller and still safely drive up to 6V outputs (this is good for when you want to control white or blue LEDs with 3.4+ forward voltages)

6 address select pins so you can wire up to 62 of these on a single i2c bus, a total of 992 outputs - that's a lot of servos or LEDs

Adjustable frequency PWM up to about 1.6 KHz

12-bit resolution for each output - for servos, that means about 4us resolution at 60Hz update rate

Configurable push-pull or open-drain output

Output enable pin to quickly disable all the outputs

We wrapped up this lovely chip into a breakout board with a couple nice extras

Terminal block for power input (or you can use the 0.1" breakouts on the side)

Reverse polarity protection on the terminal block input. The terminal block included with your product may be blue or black.

Green power-good LED

3 pin connectors in groups of 4 so you can plug in 16 servos at once (Servo plugs are slightly wider than 0.1" so you can only stack 4 next to each other on 0.1" header

"Chain-able" design

A spot to place a big capacitor on the V+ line (in case you need it)

220 ohm series resistors on all the output lines to protect them, and to make driving LEDs trivial

Solder jumpers for the 6 address select pins

This product comes with a fully tested and assembled breakout as well as 4 pieces of 3x4 male straight header (for servo/LED plugs), a 2-pin terminal block (for power) and a piece of 6-pin 0.1" header (to plug into a breadboard). A little light soldering will be required to assemble and customize the board by attaching the desired headers but it is a 15 minute task that even a beginner can do. If you want to use right-angle 3x4 headers, we also carry a 4 pack in the shop.Check out our tutorial with CircuitPython & Arduino libraries/examples, wiring diagrams, schematics, Fritzing and more!

This small digital distance sensor detects objects between 0.5 cm and 15 cm (0.2″ and 6″) away. With its quick response time, small size, low current draw, and short minimum sensing distance, this sensor is a good choice for non-contact, close-proximity object detection, and our compact carrier PCB makes it easy to integrate into your project.

These sensors are a great way to quickly detect the presence of nearby objects. It consists of a Sharp GP2Y0D805, GP2Y0D810, or GP2Y0D815 sensor module installed on our tiny carrier board for these sensors, which includes all of the external components required to make them work. The available versions offer three different sensing ranges:

Carrier with GP2Y0D805Z0F: 0.5 cm to 5 cm

Carrier with GP2Y0D810Z0F: 2 cm to 10 cm

Carrier with GP2Y0D815Z0F: 0.5 cm to 15 cm

There are a few millimeters of hysteresis around the maximum range threshold and no hysteresis at the minimum range threshold. Note that these sensors will only tell you if there is an object within the detection range along their narrow lines of sight; they will not tell you how far away the object is.

With detection distances up to 150 mm and a typical sampling rate of almost 400 Hz, these sensors provides an attractive alternative to shorter-range LED-phototransistor reflectance pairs and longer-range but slower sensors such as the Sharp GP2Y0A41SK0F analog distance sensor. The output, Vo, is driven low when the sensor detects an object; otherwise, the output is high.

Sharp GP2Y0D805Z0F digital distance sensor 5 cm measuring characteristics.

Sharp GP2Y0D810Z0F digital distance sensor 10 cm measuring characteristics.

Sharp GP2Y0D815Z0F digital distance sensor 15 cm measuring characteristics.

Some example applications include:

break-beam sensor or photogate alternative

non-contact bumper or obstacle detector

a counter or timer of objects as they pass by

The Pololu carrier board lets you interface with the GP2Y0D805, GP2Y0D810, or GP2Y0D815 sensor using a three-pin 0.1″ connector, such as the included 3×1 straight male header strip and 3×1 right-angle male header strip. You can connect to these pins with a servo cable or with a custom-made cable using pre-crimped wires and a 3×1 crimp connector housing.

The square pad is ground, the middle pad is VIN (2.7 – 6.2 V), and the remaining pad is the sensor output, OUT. Depending on your power source, you might notice an increase in performance by placing a large (>10 uF) capacitor between power and ground somewhere near the sensor.

A red LED on the back of the PCB lights when the output is low, indicating that the sensor is detecting something. With the LED in the circuit, the low output signal will be around 1 V. If so desired, you can disable this LED by cutting the trace between it and the OUT pin where it is marked on the silkscreen or by desoldering the LED, in which case the low voltage will be below 0.6 V.

The GP2Y0D805, GP2Y0D810, and GP2Y0D815 have an optional enable input that can be used to put the sensor into low-power mode. The Pololu carrier board connects this input to Vcc so that the sensor is always enabled, but you can solder a wire to the pad labeled “enable” on the back of the PCB if you want control over this input. Note that you will need to cut the trace that connects the enable line to Vcc on the PCB if you want to be able to disable the sensor. This trace is marked on the silkscreen, and there is a caret that indicates where we suggest you make the cut.

The carrier board has a 0.086″ mounting hole for a #2 or M2 screw. You can make the module more compact by cutting or grinding off this portion of the PCB if you do not need the mounting hole.

Operating voltage: 2.7 V to 6.2 V

Average current consumption: 5 mA (typical)

Distance measuring range

GP2Y0D805Z0F: 0.5 cm to 5 cm (0.2″ to 2″)

GP2Y0D810Z0F: 2 cm to 10 cm (0.8″ to 4″)

GP2Y0D815Z0F: 0.5 cm to 5 cm (0.2″ to 6″)

GP2Y0D805Z0F: 0.5 cm to 5 cm (0.2″ to 2″)

GP2Y0D810Z0F: 2 cm to 10 cm (0.8″ to 4″)

GP2Y0D815Z0F: 0.5 cm to 5 cm (0.2″ to 6″)

Output type: digital signal (low when detecting an object, high otherwise)

Steady state update period: 2.56 ms typical (3.77 ms max)

Enable pad can optionally be used to disable the emitter and save power (this feature requires you to cut a trace first)

Size without header pins: 21.6 mm × 8.9 mm × 10.4 mm (0.85″ × 0.35″ × 0.41″)

Weight without header pins: 1.5 g (0.05 oz)

Pololu carrier for Sharp GP2Y0D805Z0F, GP2Y0D810Z0F, and GP2Y0D815Z0F sensors schematic diagram.

We carry several analog Sharp distance sensors as well: the Sharp GP2Y0A51SK0F 2 – 15 cm, the Sharp GP2Y0A41SK0F 4 – 30 cm, the Sharp GP2Y0A21YK0F 10 – 80 cm, and the Sharp GP2Y0A02YK0F 20 – 150 cm. These analog distance sensors have longer minimum detection distances and much slower response times than the GP2Y0D805, GP2Y0D810, and GP2Y0D815, but they can see farther and report the distance to the detected object rather than simply if an object is detected.

A variety of Sharp distance sensors. From left to right: GP2Y0A02, GP2Y0A21 or GP2Y0A41, GP2Y0A51, and GP2Y0D8xx.

We also carry the newer Sharp GP2Y0A60SZ analog distance sensor (10 – 150 cm), which outperforms the other analog Sharp distance sensors in almost all respects, offering a low minimum detection distance, high maximum detection distance, wide 3 V output voltage differential, high 60 Hz sampling rate, operation down to 2.7 V, and optional enable control, all in a smaller package.

Sharp GP2Y0A02YK0F Sensor 20-150cm (left) next to Pololu Carrier with Sharp GP2Y0A60SZLF Sensor 10-150cm (right).

Note: This product comes with the GP2Y0D805Z0F, GP2Y0D810Z0F, or GP2Y0D815Z0F soldered into the carrier PCB. We sell the sensor modules by themselves, and we sell the carrier PCB without the sensor for those who already have the sensor or who want to solder the board together personally.

People often buy this product together with:

This small digital distance sensor detects objects between 0.5 cm and 5 cm (0.2″ and 2″) away. With its quick response time, small size, low current draw, and short minimum sensing distance, this sensor is a good choice for non-contact, close-proximity object detection, and our compact carrier PCB makes it easy to integrate into your project.

These sensors are a great way to quickly detect the presence of nearby objects. It consists of a Sharp GP2Y0D805, GP2Y0D810, or GP2Y0D815 sensor module installed on our tiny carrier board for these sensors, which includes all of the external components required to make them work. The available versions offer three different sensing ranges:

Carrier with GP2Y0D805Z0F: 0.5 cm to 5 cm

Carrier with GP2Y0D810Z0F: 2 cm to 10 cm

Carrier with GP2Y0D815Z0F: 0.5 cm to 15 cm

There are a few millimeters of hysteresis around the maximum range threshold and no hysteresis at the minimum range threshold. Note that these sensors will only tell you if there is an object within the detection range along their narrow lines of sight; they will not tell you how far away the object is.

With detection distances up to 150 mm and a typical sampling rate of almost 400 Hz, these sensors provides an attractive alternative to shorter-range LED-phototransistor reflectance pairs and longer-range but slower sensors such as the Sharp GP2Y0A41SK0F analog distance sensor. The output, Vo, is driven low when the sensor detects an object; otherwise, the output is high.

Sharp GP2Y0D805Z0F digital distance sensor 5 cm measuring characteristics.

Sharp GP2Y0D810Z0F digital distance sensor 10 cm measuring characteristics.

Sharp GP2Y0D815Z0F digital distance sensor 15 cm measuring characteristics.

Some example applications include:

break-beam sensor or photogate alternative

non-contact bumper or obstacle detector

a counter or timer of objects as they pass by

The Pololu carrier board lets you interface with the GP2Y0D805, GP2Y0D810, or GP2Y0D815 sensor using a three-pin 0.1″ connector, such as the included 3×1 straight male header strip and 3×1 right-angle male header strip. You can connect to these pins with a servo cable or with a custom-made cable using pre-crimped wires and a 3×1 crimp connector housing.

The square pad is ground, the middle pad is VIN (2.7 – 6.2 V), and the remaining pad is the sensor output, OUT. Depending on your power source, you might notice an increase in performance by placing a large (>10 uF) capacitor between power and ground somewhere near the sensor.

A red LED on the back of the PCB lights when the output is low, indicating that the sensor is detecting something. With the LED in the circuit, the low output signal will be around 1 V. If so desired, you can disable this LED by cutting the trace between it and the OUT pin where it is marked on the silkscreen or by desoldering the LED, in which case the low voltage will be below 0.6 V.

The GP2Y0D805, GP2Y0D810, and GP2Y0D815 have an optional enable input that can be used to put the sensor into low-power mode. The Pololu carrier board connects this input to Vcc so that the sensor is always enabled, but you can solder a wire to the pad labeled “enable” on the back of the PCB if you want control over this input. Note that you will need to cut the trace that connects the enable line to Vcc on the PCB if you want to be able to disable the sensor. This trace is marked on the silkscreen, and there is a caret that indicates where we suggest you make the cut.

The carrier board has a 0.086″ mounting hole for a #2 or M2 screw. You can make the module more compact by cutting or grinding off this portion of the PCB if you do not need the mounting hole.

Operating voltage: 2.7 V to 6.2 V

Average current consumption: 5 mA (typical)

Distance measuring range

GP2Y0D805Z0F: 0.5 cm to 5 cm (0.2″ to 2″)

GP2Y0D810Z0F: 2 cm to 10 cm (0.8″ to 4″)

GP2Y0D815Z0F: 0.5 cm to 5 cm (0.2″ to 6″)

GP2Y0D805Z0F: 0.5 cm to 5 cm (0.2″ to 2″)

GP2Y0D810Z0F: 2 cm to 10 cm (0.8″ to 4″)

GP2Y0D815Z0F: 0.5 cm to 5 cm (0.2″ to 6″)

Output type: digital signal (low when detecting an object, high otherwise)

Steady state update period: 2.56 ms typical (3.77 ms max)

Enable pad can optionally be used to disable the emitter and save power (this feature requires you to cut a trace first)

Size without header pins: 21.6 mm × 8.9 mm × 10.4 mm (0.85″ × 0.35″ × 0.41″)

Weight without header pins: 1.5 g (0.05 oz)

Pololu carrier for Sharp GP2Y0D805Z0F, GP2Y0D810Z0F, and GP2Y0D815Z0F sensors schematic diagram.

We carry several analog Sharp distance sensors as well: the Sharp GP2Y0A51SK0F 2 – 15 cm, the Sharp GP2Y0A41SK0F 4 – 30 cm, the Sharp GP2Y0A21YK0F 10 – 80 cm, and the Sharp GP2Y0A02YK0F 20 – 150 cm. These analog distance sensors have longer minimum detection distances and much slower response times than the GP2Y0D805, GP2Y0D810, and GP2Y0D815, but they can see farther and report the distance to the detected object rather than simply if an object is detected.

A variety of Sharp distance sensors. From left to right: GP2Y0A02, GP2Y0A21 or GP2Y0A41, GP2Y0A51, and GP2Y0D8xx.

We also carry the newer Sharp GP2Y0A60SZ analog distance sensor (10 – 150 cm), which outperforms the other analog Sharp distance sensors in almost all respects, offering a low minimum detection distance, high maximum detection distance, wide 3 V output voltage differential, high 60 Hz sampling rate, operation down to 2.7 V, and optional enable control, all in a smaller package.

Sharp GP2Y0A02YK0F Sensor 20-150cm (left) next to Pololu Carrier with Sharp GP2Y0A60SZLF Sensor 10-150cm (right).

Note: This product comes with the GP2Y0D805Z0F, GP2Y0D810Z0F, or GP2Y0D815Z0F soldered into the carrier PCB. We sell the sensor modules by themselves, and we sell the carrier PCB without the sensor for those who already have the sensor or who want to solder the board together personally.

People often buy this product together with:

This small digital distance sensor detects objects between 2 cm and 10 cm (0.8″ and 4″) away. With its quick response time, small size, and low current draw, this sensor is a good choice for non-contact object detection, and our compact carrier PCB makes it easy to integrate into your project.

These sensors are a great way to quickly detect the presence of nearby objects. It consists of a Sharp GP2Y0D805, GP2Y0D810, or GP2Y0D815 sensor module installed on our tiny carrier board for these sensors, which includes all of the external components required to make them work. The available versions offer three different sensing ranges:

Carrier with GP2Y0D805Z0F: 0.5 cm to 5 cm

Carrier with GP2Y0D810Z0F: 2 cm to 10 cm

Carrier with GP2Y0D815Z0F: 0.5 cm to 15 cm

There are a few millimeters of hysteresis around the maximum range threshold and no hysteresis at the minimum range threshold. Note that these sensors will only tell you if there is an object within the detection range along their narrow lines of sight; they will not tell you how far away the object is.

With detection distances up to 150 mm and a typical sampling rate of almost 400 Hz, these sensors provides an attractive alternative to shorter-range LED-phototransistor reflectance pairs and longer-range but slower sensors such as the Sharp GP2Y0A41SK0F analog distance sensor. The output, Vo, is driven low when the sensor detects an object; otherwise, the output is high.

Sharp GP2Y0D805Z0F digital distance sensor 5 cm measuring characteristics.

Sharp GP2Y0D810Z0F digital distance sensor 10 cm measuring characteristics.

Sharp GP2Y0D815Z0F digital distance sensor 15 cm measuring characteristics.

Some example applications include:

break-beam sensor or photogate alternative

non-contact bumper or obstacle detector

a counter or timer of objects as they pass by

The Pololu carrier board lets you interface with the GP2Y0D805, GP2Y0D810, or GP2Y0D815 sensor using a three-pin 0.1″ connector, such as the included 3×1 straight male header strip and 3×1 right-angle male header strip. You can connect to these pins with a servo cable or with a custom-made cable using pre-crimped wires and a 3×1 crimp connector housing.

The square pad is ground, the middle pad is VIN (2.7 – 6.2 V), and the remaining pad is the sensor output, OUT. Depending on your power source, you might notice an increase in performance by placing a large (>10 uF) capacitor between power and ground somewhere near the sensor.

A red LED on the back of the PCB lights when the output is low, indicating that the sensor is detecting something. With the LED in the circuit, the low output signal will be around 1 V. If so desired, you can disable this LED by cutting the trace between it and the OUT pin where it is marked on the silkscreen or by desoldering the LED, in which case the low voltage will be below 0.6 V.

The GP2Y0D805, GP2Y0D810, and GP2Y0D815 have an optional enable input that can be used to put the sensor into low-power mode. The Pololu carrier board connects this input to Vcc so that the sensor is always enabled, but you can solder a wire to the pad labeled “enable” on the back of the PCB if you want control over this input. Note that you will need to cut the trace that connects the enable line to Vcc on the PCB if you want to be able to disable the sensor. This trace is marked on the silkscreen, and there is a caret that indicates where we suggest you make the cut.

The carrier board has a 0.086″ mounting hole for a #2 or M2 screw. You can make the module more compact by cutting or grinding off this portion of the PCB if you do not need the mounting hole.

Operating voltage: 2.7 V to 6.2 V

Average current consumption: 5 mA (typical)

Distance measuring range

GP2Y0D805Z0F: 0.5 cm to 5 cm (0.2″ to 2″)

GP2Y0D810Z0F: 2 cm to 10 cm (0.8″ to 4″)

GP2Y0D815Z0F: 0.5 cm to 5 cm (0.2″ to 6″)

GP2Y0D805Z0F: 0.5 cm to 5 cm (0.2″ to 2″)

GP2Y0D810Z0F: 2 cm to 10 cm (0.8″ to 4″)

GP2Y0D815Z0F: 0.5 cm to 5 cm (0.2″ to 6″)

Output type: digital signal (low when detecting an object, high otherwise)

Steady state update period: 2.56 ms typical (3.77 ms max)

Enable pad can optionally be used to disable the emitter and save power (this feature requires you to cut a trace first)

Size without header pins: 21.6 mm × 8.9 mm × 10.4 mm (0.85″ × 0.35″ × 0.41″)

Weight without header pins: 1.5 g (0.05 oz)

Pololu carrier for Sharp GP2Y0D805Z0F, GP2Y0D810Z0F, and GP2Y0D815Z0F sensors schematic diagram.

We carry several analog Sharp distance sensors as well: the Sharp GP2Y0A51SK0F 2 – 15 cm, the Sharp GP2Y0A41SK0F 4 – 30 cm, the Sharp GP2Y0A21YK0F 10 – 80 cm, and the Sharp GP2Y0A02YK0F 20 – 150 cm. These analog distance sensors have longer minimum detection distances and much slower response times than the GP2Y0D805, GP2Y0D810, and GP2Y0D815, but they can see farther and report the distance to the detected object rather than simply if an object is detected.

A variety of Sharp distance sensors. From left to right: GP2Y0A02, GP2Y0A21 or GP2Y0A41, GP2Y0A51, and GP2Y0D8xx.

We also carry the newer Sharp GP2Y0A60SZ analog distance sensor (10 – 150 cm), which outperforms the other analog Sharp distance sensors in almost all respects, offering a low minimum detection distance, high maximum detection distance, wide 3 V output voltage differential, high 60 Hz sampling rate, operation down to 2.7 V, and optional enable control, all in a smaller package.

Sharp GP2Y0A02YK0F Sensor 20-150cm (left) next to Pololu Carrier with Sharp GP2Y0A60SZLF Sensor 10-150cm (right).

Note: This product comes with the GP2Y0D805Z0F, GP2Y0D810Z0F, or GP2Y0D815Z0F soldered into the carrier PCB. We sell the sensor modules by themselves, and we sell the carrier PCB without the sensor for those who already have the sensor or who want to solder the board together personally.

People often buy this product together with:

This is a board designed for opto-isolation. This board is helpful for connecting digital systems (like a 5V microcontroller) to a high-voltage or noisy system. This board electrically isolates a controller from the high-power system by use of an opto-isolator IC. This IC has two LEDs and two photodiodes built-in. This allows the low-voltage side to control a high voltage side.

We often use this board to allow a microcontroller control servos or other motors that use a higher voltage than the TTL logic on the (3.3V or 5V) micro, and may cause electromagnetic interferance with our system as the motors turn on and off. This board will isolate the systems, creating a type of electrical noise barrier between devices.

This breakout board uses the ILD213T optoisolator and discrete transistors to correct the logic. Comes with two channels. Great for use in noisy circuits where signal lines require electrical isolation.

A normal LED opto-isolator will invert the logic of a signal. We threw some transistors on this compact board to correct the inversion. What you put into the IN pins, will be replicated on the the OUT pins, but at the higher voltage (HV).

This sensor module has 8 IR LED/phototransistor pairs mounted on a 0.375" pitch, making it a great detector for a line-following robot. Pairs of LEDs are arranged in series to halve current consumption, and a MOSFET allows the LEDs to be turned off for additional sensing or power-savings options. Each sensor provides a separate digital I/O-measurable output.

Note: The QTR-8RC reflectance sensor array requires digital I/O lines to take readings. The similar QTR-8A reflectance sensor array is available with analog outputs, and the reflectance sensor is available individually as a QTR-1RC reflectance sensor or QTR-1A reflectance sensor.

Functional Description

The QTR-8RC reflectance sensor array is intended as a line sensor, but it can be used as a general-purpose proximity or reflectance sensor. The module is a convenient carrier for eight IR emitter and receiver (phototransistor) pairs evenly spaced at intervals of 0.375" (9.525 mm). To use a sensor, you must first charge the output node by applying a voltage to its OUT pin. You can then read the reflectance by withdrawing the externally supplied voltage and timing how long it takes the output voltage to decay due to the integrated phototransistor. Shorter decay time is an indication of greater reflection. This measurement approach has several advantages, especially when coupled with the ability of the QTR-8RC module to turn off LED power:

No analog-to-digital converter (ADC) is required

Improved sensitivity over voltage-divider analog output

Parallel reading of multiple sensors is possible with most microcontrollers

Parallel reading allows optimized use of LED power enable option

The outputs are all independent, but the LEDs are arranged in pairs to halve current consumption. The LEDs are controlled by a MOSFET with a gate normally pulled high, allowing the LEDs to be turned off by setting the MOSFET gate to a low voltage. Turning the LEDs off might be advantageous for limiting power consumption when the sensors are not in use or for varying the effective brightness of the LEDs through PWM control.

This sensor was designed to be used with the board parallel to the surface being sensed.

The LED current-limiting resistors for 5 V operation are arranged in two stages; this allows a simple bypass of one stage to enable operation at 3.3 V. The LED current is approximately 20–25 mA, making the total board consumption just under 100 mA. The schematic diagram of the module is shown below:

For a similar array with three sensors, consider our QTR-3RC reflectance sensor array. The sensors on the QTR-8RC are also available individually as the QTR-1RC reflectance sensor, and the QTR-L-1RC is an alternative designed to be used with the board perpendicular to the surface.

QTR sensor size comparison. Clockwise from top left: QTR-3RC, QTR-1RC, QTR-L-1RC, QTR-8RC.

Specifications

Dimensions: 2.95" x 0.5" x 0.125" (without header pins installed)

Operating voltage: 3.3-5.0 V

Supply current: 100 mA

Output format: 8 digital I/O-compatible signals that can be read as a timed high pulse

Optimal sensing distance: 0.125" (3 mm)

Maximum recommended sensing distance: 0.375" (9.5 mm)

Weight without header pins: 0.11 oz (3.09 g)

QTR-1RC output (yellow) when 1/8" above a black line and microcontroller timing of that output (blue).

Interfacing the QTR-8RC Outputs to Digital I/O Lines

The QTR-8RC module has eight identical sensor outputs that, like the Parallax QTI, require a digital I/O line capable of driving the output line high and then measuring the time for the output voltage to decay. The typical sequence for reading a sensor is:

Turn on IR LEDs (optional).

Set the I/O line to an output and drive it high.

Allow at least 10 μs for the sensor output to rise.

Make the I/O line an input (high impedance).

Measure the time for the voltage to decay by waiting for the I/O line to go low.

Turn off IR LEDs (optional).

These steps can typically be executed in parallel on multiple I/O lines.

With a strong reflectance, the decay time can be as low as several dozen microseconds; with no reflectance, the decay time can be up to a few milliseconds. The exact time of the decay depends on your microcontroller’s I/O line characteristics. Meaningful results can be available within 1 ms in typical cases (i.e. when not trying to measure subtle differences in low-reflectance scenarios), allowing up to 1 kHz sampling of all 8 sensors. If lower-frequency sampling is sufficient, substantial power savings can be realized by turning off the LEDs. For example, if a 100 Hz sampling rate is acceptable, the LEDs can be off 90% of the time, lowering average current consumption from 100 mA to 10 mA.

Our Pololu AVR library provides functions that make it easy to use these sensors with our Orangutan robot controllers; please see the QTR Reflectance Sensors section of our library command reference for more information. We also have a Arduino library for these sensors.

Breaking the Module in Two

If you don’t need or cannot fit all eight sensors, you can break off two sensors and still use all 8 sensors as two separate modules, as shown below. The PCB can be scored from both sides along the perforation and then bent until it snaps apart. Each of the two resulting pieces will function as an independent line sensor.

Included Components

This module ships with a 25-pin 0.1" header strip and a 100 Ohm through-hole resistor as shown below.

You can break the header strip into smaller pieces and solder them onto your reflectance sensor array as desired, or you can solder wires directly to the unit or use a right-angle header strip for a more compact installation. The pins on the module are arranged so that they can all be accessed using either an 11×1 strip or an 8×2 strip.

The resistor is required to make the two-sensor array functional after the original eight-sensor array is broken into two pieces. This resistor is only needed once the board has been broken.

Solder the included resistor to the 2-sensor array piece as shown to make the separated piece functional.

How it works in detail

For more information about how this sensor works, see the “How it works in detail” section of the QTR-1RC product page.

People often buy this product together with:

Your electronics can now see in dazzling color with this lovely color light sensor. We found the best color sensor on the market, the TCS34725, which has RGB and Clear light sensing elements. An IR blocking filter, integrated on-chip and localized to the color sensing photodiodes, minimizes the IR spectral component of the incoming light and allows color measurements to be made accurately. The filter means you'll get much truer color than most sensors, since humans don't see IR. The sensor also has an incredible 3,800,000:1 dynamic range with adjustable integration time and gain so it is suited for use behind darkened glass.We add supporting circuitry as well, such as a 3.3V regulator so you can power the breakout with 3-5VDC safely and level shifting for the I2C pins so they can be used with 3.3V or 5V logic. Finally, we specified a nice neutral 4150°K temperature LED with a MOSFET driver onboard to illuminate what you're trying to sense. The LED can be easily turned on or off by any logic level output.Connect to any microcontroller with I2C and our example code will quickly get you going with 4 channel readings. We include some example code to detect light lux and temperature that we snagged from the eval board software.A detailed tutorial is here, check out our Arduino library and follow our tutorial to install. Wire up the sensor by connecting VDD to 3-5VDC, Ground to common ground, SCL to I2C Clock and SDA to I2C Data on your Arduino. Restart the IDE and select the example sketch and start putting all your favorite fruit next to the sensor element!

RGB Color Sensor with IR filter - TCS34725 (19:36)

Remember when you were a kid and there was a birthday party at the pool and your parents totally embarrassed you by slathering you all over with sunscreen and you were all "MOM I HAVE ENOUGH SUNSCREEN" and she wouldn't listen? Well, if you had this UV Index sensor connected up to an Arduino you could have said "According to this calibrated SI1145 sensor from SiLabs, the UV index right now is 4.5 which means I do not need more sunscreen" and she would have been so impressed with your project that you could have spent more time splashing around.

The SI1145 is a new sensor from SiLabs with a calibrated light sensing algorithm that can calculate UV Index. It doesn't contain an actual UV sensing element, instead it approximates it based on visible & IR light from the sun. We took this outside a couple days and compared the calculated UV index with the news-reported index and found it was very accurate! It's a digital sensor that works over I2C so just about any microcontroller can use it. The sensor also has individual visible and IR sensing elements so you can measure just about any kind of light - we only wrote our library to printout the 'counts' rather than the calculate the exact values of IR and Visible light so if you need precision Lux measurement check out the TSL2561. If you're feeling really advanced, you can connect up an IR LED to the LED pin and use the basic proximity sensor capability that is in the SI1145 as well.

We wrapped this nice little sensor up on a PCB with level shifting and regulation circuitry so you can safely use it with 3 or 5V microcontrollers. If you are using an Arduino, we've got a lovely tutorial and library already written up with example code so you can quickly read sensor readings and the UV index in under 10 minutes. Each order comes with one fully assembled and tested PCB breakout and a small piece of header. You'll need to solder the header onto the PCB but it's fairly easy and takes only a few minutes even for a beginner.

This is a breakout board for Freescale’s MPR121QR2. The MPR121 is a capacitive touch sensor controller driven by an I2C interface. The chip can control up to twelve individual electrodes, as well as a simulated thirteenth electrode. The MPR121 also features eight LED driving pins. When these pins are not configured as electrodes, they may be used to drive LEDs.

There a four jumpers on the bottom of the board, all of which are set (closed) by default. An address jumper ties the ADD pin to ground, meaning the default I2C address of the chip will be 0x5A. If you need to change the address of the chip (by shorting ADD to a different pin), make sure you open the jumper first. Jumpers also connect SDA, SCL and the interrupt pin to 10k pull-up resistors. If you don’t require the pull-up resistors you can open the jumpers by cutting the trace connecting them.

There is no regulation on the board, so the voltage supplied should be between 2.5 and 3.6VDC. The VREG pin is connected through a 0.1uF capacitor to ground, which means, unless you modify the board, you can’t operate the MPR121 in low-supply voltage mode (1.71-2.75VDC).

A new collaboration between Adafruit & Micah from Scanlime, we are excited to introduce Fadecandy, a NeoPixel driver with built in dithering, that can be controlled over USB. Fadecandy is not just hardware! It is a kit of both hardware and software parts that make LED art projects easier to build and better-looking so sculptors and makers and multimedia artists can concentrate on beautiful things instead of reinventing the wheel. It's an easy way to get started and an advanced tool for professionals. It's a collection of simple parts that work well together:

Firmware that uses unique dithering and color correction algorithms to raise the bar for quality while getting out of the way of your creativity.

Open source hardware for connecting cheap and popular WS2811 based LEDs to a laptop, desktop, or Raspberry Pi over USB.

Fadecandy Server Software, which communicates with one Fadecandy board or dozens. It runs on Windows, Linux, and Mac OS, and on embedded platforms like Raspberry Pi.

The Open Pixel Control protocol, a simple way of getting pixel data from your creative tools into the Fadecandy server.

Libraries and examples for popular languages. We have Python and Processing already, with Javascript and Max coming soon.

LEDs! Fadecandy works with Adafruit's popular WS2811/WS2812 LEDs. Each controller board supports up to 512 LEDs, arranged as 8 strips of 64 each. Not for use with RGBW NeoPixels, you can only use RGB type at this time.

Headers are not included but we have tons of different kinds of dual header in the shop if you want to solder something into the pads.Fadecandy is designed to enable art that is subtle, interactive, and playful - exploring the interplay between light, form, and shadow. If you’re tired of seeing project after project with frenetic blinky rainbow fades, you’ll appreciate how easy it is to create expressive lighting!It's also battle tested! The firmware was originally developed to run the Ardent Mobile Cloud Platform, a Burning Man project which used 2500 LEDs to project ever-changing rolling cloud patterns onto the interior of a translucent plastic sculpture. It used five Fadecandy boards, a single Raspberry Pi, and the effects were written in a mixture of C and Python. The lighting on this project blew people away, and it made me realize just how much potential there is for creative lighting, but it takes significant technical drudgery to get beyond frenetic-rainbow-fade into territory where the lighting can really add to an art piece instead of distracting from it. How it's made - Ladyada and Micah Scott manufacturing Fadecandy at Adafruit.

FadeCandy - Dithering USB-Controlled Driver for NeoPixels (18:41)

The QTR-1RC reflectance sensor carries a single infrared LED and phototransistor pair in an inexpensive, tiny 0.5" x 0.3" module that can be mounted almost anywhere and is great for edge detection and line following. The output is designed to be measured by a digital I/O line. This sensor is sold in packs of two units.

Note: The QTR-1RC reflectance sensor requires a digital I/O line to take readings. The similar QTR-1A reflectance sensor is available with an analog output.

Functional description

The Pololu QTR-1RC reflectance sensor carries a single infrared (IR) LED and phototransistor pair. To use the sensor, you must first charge the output node by applying a voltage to the OUT pin. You can then read the reflectance by withdrawing the externally supplied voltage and timing how long it takes the output voltage to decay due to the integrated phototransistor. Shorter decay time is an indication of greater reflection. This measurement approach has several advantages, especially when multiple units are used:

No analog-to-digital converter (ADC) is required

Improved sensitivity over voltage-divider analog output

Parallel reading of multiple sensors is possible with most microcontrollers

The LED current-limiting resistor is set to deliver approximately 17 mA to the LED when VIN is 5 V. The current requirement can be met by some microcontroller I/O lines, allowing the sensor to be powered up and down through an I/O line to conserve power.

This sensor was designed to be used with the board parallel to the surface being sensed. Because of its small size, multiple units can easily be arranged to fit various applications such as line sensing and proximity/edge detection.

For a line sensor with eight of these units arranged in a row, please see the QTR-8RC reflectance sensor array; for a similar array of three slightly different sensor components, see the QTR-3RC. For a similar, smaller sensor with longer range, and intended for use with the board perpendicular to the surface, please see the QTR-L-1RC reflectance sensor.

QTR sensor size comparison. Clockwise from top left: QTR-3RC, QTR-1RC, QTR-L-1RC, QTR-8RC.

Specifications

Dimensions: 0.3" x 0.5" x 0.1" (without optional header pins installed)

Operating voltage: 5.0 V

Supply current: 17 mA

Output format: digital I/O-compatible signal that can be read as a timed high pulse

Optimal sensing distance: 0.125" (3 mm)

Maximum recommended sensing distance: 0.375" (9.5 mm)

Weight without header pins: 0.008 oz (0.2 g)

QTR-1RC output (yellow) when 1/8" above a black line and microcontroller timing of that output (blue).

Interfacing the QTR-1RC output to a digital I/O line

Like the Parallax QTI, this sensor requires a digital I/O line capable of driving the output line high and then measuring the time for the output voltage to decay. The typical sequence for reading a sensor is:

Set the I/O line to an output and drive it high.

Allow at least 10 μs for the sensor output to rise.

Make the I/O line an input (high impedance).

Measure the time for the voltage to decay by waiting for the I/O line to go low.

These steps can typically be executed in parallel on multiple I/O lines.

With a strong reflectance, the decay time can be as low as several dozen microseconds; with no reflectance, the decay time can be up to a few milliseconds. The exact time of the decay depends on your microcontroller’s I/O line characteristics. Meaningful results can be available within 1 ms in typical cases (i.e. when not trying to measure subtle differences in low-reflectance scenarios), allowing up to 1 kHz sampling.

Our Pololu AVR library provides functions that make it easy to use these sensors with our Orangutan robot controllers; please see the QTR Reflectance Sensors section of our library command reference for more information. We also have a Arduino library for these sensors.

Included components

This module has a single mounting hole intended for a #2 screw (not included); if this mounting hole is not needed, this portion of the PCB can be ground off to make the unit even smaller. Each pack of two reflectance sensors includes sets of straight male header strips and right-angle male header strips, which allow you to mount them in the orientation of your choice (note: the header pins might ship as 1×6 strips that you can break into two 1×3 pieces). You can also solder wires, such as ribbon cable, directly to the pads for the most compact installation.

How it works in detail

With only four components (or five, if you count the coupled IR LED and phototransistor separately), the operation of this sensor is relatively basic. The emitter side is just an IR LED with an appropriate current-limiting resistor. The light from the emitter leaves the sensor, reflects off a nearby surface, and returns to the detector.

The detector side is a resistor-capacitor (RC) circuit, where the resistance comes from the phototransistor and is a measure of the incident infrared light, and the decay time is proportional to the resistance. The first step of the sensor-reading process—driving the sensor output high—discharges the integrated 10 nF capacitor and puts both sides at the same voltage (VIN). Alternatively, you can think of this as “charging the output node”, and it is functionally equivalent to charging a capacitor with one side connected to ground. Once you are no longer supplying an external voltage to the output pin, the capacitor can slowly charge through the phototransistor, with the rate of charging being a function of the phototransistor’s resistance (which is in turn a function of the incident IR). As the capacitor charges, the voltage on the output side drops, eventually reaching zero when the capacitor is fully charged. Alternatively, you can think of this as “discharging the output node”, and it is functionally equivalent to discharging a capacitor with one side connected to ground.

The 220 Ω resistor on the OUT line serves to limit the current flow, making it possible for a microcontroller output to safely charge the output node prior to each reading. It has very little effect on the sensor output.

QTR-1RC and QTR-L-1RC reflectance sensor schematic diagram.

QTR-1RC output (yellow) when 1/8" above a white/black interface and microcontroller timing of that output (blue).

People often buy this product together with:

This small, inexpensive motor controller allows variable speed and direction control of two small, brushed DC motors using a simple serial interface, making it easy to add motors to your microcontroller- or computer-based project. The motor supply voltage range is 4.5 to 13.5 V; the continuous current per channel is up to 1 A (3 A peak). The logic supply can be as low as 2.7 V, allowing operation with modern microcontrollers running at 3.3 V.

The qik 2s9v1 is Pololu’s second-generation dual serial motor controller. The compact module allows any microcontroller or computer with a serial port (external RS-232 level converter required) or USB-to-serial adapter to easily drive two small, brushed DC motors with full direction and speed control. It provides ultrasonic, 8-bit PWM speed control via an advanced, two-way serial protocol that features automatic baud rate detection up to 38.4 kbps and optional CRC error checking. Two status LEDs give visual feedback about the serial connection and any encountered error conditions, making debugging easy, and a demo mode allows easy verification of proper operation.

The improvements over the previous generation and competing products include:

high-frequency (ultrasonic) PWM to eliminate switching-induced motor shaft hum or whine

a robust, high-speed communication protocol with user-configurable error condition response

visible LEDs and a demo mode to help troubleshoot problematic installations

reverse power protection on the motor supply (not on the logic supply)

For a more advanced, higher-power version of this controller, please consider the qik 2s12v10. For a simpler carrier of the qik’s motor driver, please consider the TB6612FNG dual motor driver carrier, and for a robot controller based on the qik’s driver, please consider the Baby Orangutan and Orangutan SV-328 robot controllers and 3pi robot, which connect the TB6612 to a user-programmable AVR microcontroller.

November 27, 2013 update: We have changed this product by replacing the large, silver electrolytic capacitor with a much smaller ceramic capacitor. This lowers the profile of the board but does not affect functionality at all. The main product picture shows this new version; the rest of the pictures on this product page still show the previous version with the tall electrolytic capacitor.

Simple bidirectional control of two DC brush motors.

4.5 V to 13.5 V motor supply range.

1 A maximum continuous current per motor (3 A peak).

2.7 V to 5.5 V logic supply range.

Logic-level, non-inverted, two-way serial control for easy connection to microcontrollers or robot controllers.

Optional automatic baud rate detection.

Two on-board indicator LEDs (status/heartbeat and serial error indicator) for debugging and feedback.

Serial error output to make it easier for the main controller to recover from a serial error condition.

Jumper-enabled demo mode allows initial testing without any programming.

Optional CRC error detection eliminates serial errors caused by noise or software faults.

Optional motor shutdown on serial error or timeout for additional safety.

Supports daisy-chaining the qik to other qiks and Pololu serial motor and servo controllers, allowing the control of up to hundreds of motors and servos with a single serial line.

Comprehensive user’s guide.

The qik ships with a 16×1 straight 0.100" male header strip, a 12×1 right angle 0.100" male header strip, and two red shorting blocks. This hardware offers several options when it comes to making connections to the qik.

For the most compact installation, wires can be directly soldered to the qik pins themselves. For less permanent connections, the 16×1 straight header strip can be broken into a 12×1 piece and two 2×1 pieces. The 2×1 pieces can optionally be soldered into the jumper pins, and the 12×1 header strip of your choice can be soldered into the qik control pins. This allows connections to the qik via custom-made cables that have female headers on them, or the qik can simply be plugged into a breadboard. Using the right angle header allows for a compact profile or for vertical mounting into a breadboard; using the straight header allows for breadboarding as shown in the picture above.

We have written a basic Arduino library for the qik dual serial motor controllers that makes it simple to interface these controllers with an Arduino. The library handles the details of serial communication with the qik, allowing two brushed DC motors to be controlled easily.

People often buy this product together with:

What is better than smart RGB LEDs? Smart RGB+White LEDs! These NeoPixels now have 4 LEDs in them (red, green, blue and white) for excellent lighting effects. Round and round and round they go!  

This is the NeoPixel 1/4 60 LED Ring in Cool White. We have a ton of other NeoPixel rings in the store to check out!

With four of these you can make a huge ring with 60 ultra bright smart LED NeoPixels are arranged in a circle with a 6.2" diameter. Each order comes with just the quarter ring. Four of this item are required to make a large ring. You will have to solder them together as well, so for the full ring of 60 LEDs, buy four and solder them together!

The rings are 'chainable' - connect the output pin of one to the input pin of another. Use only one microcontroller pin to control as many as you can chain together! Each LED is addressable as the driver chip is inside the LED. Each one has ~18mA constant current drive so the color will be very consistent even if the voltage varies, and no external choke resistors are required making the design slim. Power the whole thing with 5VDC and you're ready to rock.

The NeoPixel is 'split', one half is the RGB you know and love, the other half is a white LED with a yellow phosphor. Unlit, it resembles an egg yolk. Lit up these are insanely bright (like ow my eye hurts) and can be controlled with 8-bit PWM per channel (8 x 4 channels = 32-bit color overall). Great for adding lots of colorful + white dots to your project!

NeoPixel LEDs use 800 KHz protocol so specific timing is required. On NeoPixels, the PWM rate is ~400 Hz, which works well but is noticable if the LED is moving. In comparison, DotStars have a 20 KHz PWM rate, so even when moving the LED around, you won't see the pixelation, the blending is very smooth. (we recommend DotStars if you can use them)

NeoPixels are 5050-sized LEDs with an embedded microcontroller inside the LED. You can set the brightness and color of each R/G/B/W with 8-bit PWM precision (so 32-bit color per pixel). The LEDs are controlled by shift-registers and only 1 digital output pin are required to send data down. The PWM is built into each LED-chip so once you set the color you can stop talking to the ring and it will continue to PWM all the LEDs for you.

We have a tutorial showing wiring, power usage calculations, example code for usage, etc. for NeoPixel Please check it out! Please note you will need a NeoPixel library with RGBW support which is not always available. If you try to control these with a plain 'RGB' NeoPixel library, you'll get very weird results. Our Adafruit NeoPixel library does support RGBW but if you're using something else, just be aware that it might require some hacking.

Our detailed NeoPixel Uberguide has everything you need to use NeoPixels in any shape and size. Including ready-to-go library & example code for the Arduino UNO/Duemilanove/Diecimila, Flora/Micro/Leonardo, Trinket/Gemma, Arduino Due & Arduino Mega/ADK (all versions)

Comes with one quarter ring of 15 x individually addressable RGB LEDs assembled and tested. We recommend you buy four to build the full circle as this is just the 1/4 of the circle.

What is better than smart RGB LEDs? Smart RGB+White LEDs! These NeoPixel rings now have 4 LEDs in them (red, green, blue and white) for excellent lighting effects. Round and round and round they go!  

This is the 24 LED RGBW NeoPixel Ring in Cool White. We have a ton of other NeoPixel rings in the store to check out!

24 ultra bright smart LED NeoPixels are arranged in a circle with 2.58" (65.5mm) outer diameter. The rings are 'chainable' - connect the output pin of one to the input pin of another. Use only one microcontroller pin to control as many as you can chain together! Each LED is addressable as the driver chip is inside the LED. Each one has ~18mA constant current drive so the color will be very consistent even if the voltage varies, and no external choke resistors are required making the design slim. Power the whole thing with 5VDC and you're ready to rock.

The NeoPixel is 'split', one half is the RGB you know and love, the other half is a white LED with a yellow phosphor. Unlit, it resembles an egg yolk. Lit up these are insanely bright (like ow my eye hurts) and can be controlled with 8-bit PWM per channel (8 x 4 channels = 32-bit color overall). Great for adding lots of colorful + white dots to your project!

NeoPixel LEDs use 800 KHz protocol so specific timing is required. On NeoPixels, the PWM rate is ~400 Hz, which works well but is noticable if the LED is moving. In comparison, DotStars have a 20 KHz PWM rate, so even when moving the LED around, you won't see the pixelation, the blending is very smooth. (we recommend DotStars if you can use them)

NeoPixels are 5050-sized LEDs with an embedded microcontroller inside the LED. You can set the brightness and color of each R/G/B/W with 8-bit PWM precision (so 32-bit color per pixel). The LEDs are controlled by shift-registers and only 1 digital output pin are required to send data down. The PWM is built into each LED-chip so once you set the color you can stop talking to the ring and it will continue to PWM all the LEDs for you.

We have a tutorial showing wiring, power usage calculations, example code for usage, etc. for NeoPixel Please check it out! Please note you will need a NeoPixel library with RGBW support which is not always available. If you try to control these with a plain 'RGB' NeoPixel library, you'll get very weird results. Our Adafruit NeoPixel library does support RGBW but if you're using something else, just be aware that it might require some hacking.

Our detailed NeoPixel Uberguide has everything you need to use NeoPixels in any shape and size. Including ready-to-go library & example code for the Arduino UNO/Duemilanove/Diecimila, Flora/Micro/Leonardo, Trinket/Gemma, Arduino Due & Arduino Mega/ADK (all versions)

Comes as a single ring with 24 individually addressable RGBW LEDs assembled and tested.

Add some dazzle to your Spark Core or Photon with this custom-made NeoPixel ring kit! 24 ultra bright smart LED NeoPixels are arranged in a circle with 2.6" (66mm) outer diameter. Snap in your Spark and upload the NeoPixel library code to light up the LEDs, make an Internet of Blinky! Each LED is addressable as the driver chip is inside the LED. Each one has ~18mA constant current drive so the color will be very consistent even if the voltage varies, and no external choke resistors are required making the design slim. Power the whole thing with about 3.5-5.5 VDC battery pack and you're ready to rock.

To make your project portable, we have a JST connector for attaching an external battery. Power with 3.5 - 5.5V DC, a rechargeable LiPoly or LiIon cell battery works great, or 3xAAA or 3xAA battery pack. The JST included is so you can make your own battery connection. Use pin D6 for the NeoPixel library code, all other pins are availale to use and have two breakouts on either side so you can wire up other sensors or devices.

Comes as a single round PCB with 24 individually addressable RGB LEDs assembled and tested, two 12 pin 0.1" socket headers and a bonus JST cable. Some light soldering is required, you can solder the two sockets in place to allow unplugging of the Spark, or just solder it directly in place for a slimmer look.

Please Note: Particle (Spark) Core/Photon and Battery not included (but we do have them in the shop!)

These LED strips are ultra bright, fun and glowy. There are 60 cool white LEDs per meter, and you can control the entire strip at once with any microcontroller and a power transistor. The way they are wired, you will need a 9-12VDC power supply and connect directly. If you want to dim the strip, use any NPN or N-channel MOSFET (although the big powerful kind is good for a large strip) and PWM the input.We splurged and got the weatherproof kind with white background color. There's a 3M adhesive strip on the back which should stick to most smooth surfaces. Great for architectural lighting (under-counter or under-cabinet), decorating your bicycle or car, making lamps, etc. You'll need a lot of power to light these up, we suggest our 12V 5A supply. To connect it to a power supply, pick up a 2.1mm female jack and wire it to the strip with some heat shrink. For portable use, we suggest a 8xAA battery holderPlease Note: these strips are weatherproof so they'll be more rugged than uncoated strips, but they not designed for long term submersion in water, especially chlorinated water, or exposed to UV (eg sunlight) for extended periods of time. They are for indoor use or light outdoor use without direct sun/water. That means you cannot put them into a pool, lake, aquarium, etc. The silk-screening and LED brightness of the strips may vary slightly from reel to reel. Once the adhesive backing has been removed, the strips are not returnable!You can cut this stuff pretty easily with wire cutters, there are cut-lines every 5cm (3 LEDs each), and trim off the weatherproof cover with a hobby knife. Solder to the 0.1" copper pads and you're good to go.They come in 5 meter reels and are sold by the meter! If you buy 5m at a time, you'll get full reels. If you buy less than 5m, you'll get a single strip, but it will be a cut piece from a reel which may or may not have a connector on it. If the piece comes from the end of the reel, the connector may be on the output end of the strip!We don't have a tutorial specifically for the white LED strips but they're basically identical to the RGB LED strips we carry, except that instead of 3 different colored LEDs there is only cool white so we suggest our tutorial on thoseWhen purchasing a full reel, there will be two wires on either side you can connect directly to 12V. Be sure to try both 'directions' as the wire colors do not necessarily indicate which wire is the ground wire. It will not damage the strip if you connect it backwards so if it isn't lighting, try the other way! When purchasing a smaller piece, if you have 4 pads labeled RGB connect the RGB pads together and tie those to ground and connect the 12V+ pad to 12VDC

Move over NeoPixels, there's a new LED strip in town! These fancy new DotStar LED strips are a great upgrade for people who have loved and used NeoPixel strips for a few years but want something even better. DotStar LEDs use generic 2-wire SPI, so you can push data much faster than with the NeoPixel 800 KHz protocol and there's no specific timing required. They also have much higher PWM refresh rates, so  you can do Persistence-of-Vision (POV) and have less flickering, particularly at low brightness levels.

Make your own smart Cool White LED arrangement with the same integrated LED driver that is used in our DotStar or NeoPixel LED strips.  Unlit, the color resembles a yellow Starburst. Lit up these are insanely bright (like ow my eye hurts) and can be controlled with 24 bit high-frequency PWM. The phosphor helps diffuse the 3 white dies inside together for a very bright but consistant light, compared to what you get by trying to mix RGB to make white (which never quite looks right)

However, unlike NeoPixels, these LEDs have 2 wires (input and output) for sending data - one clock pin and one data pin. That means you need two pins, not one, to control DotStars. Because the clock and data is separated, you can use any processor speed or type to control these strips, and you don't have to worry about being careful with the timing. Hardware SPI support is handy but not required. This makes them excellent for use with any microcontroller or microprocessor, including Arduino, Raspberry Pi, BeagleBone, Propeller, SparkCore, and any 'raw' microcontrollers/microprocessors. It's very easy to port the library, and you can send data to the pixels at up to 32MHz clock rate!

NeoPixel LEDs use 800 KHz protocol so specific timing is required. On NeoPixels, the PWM rate is 400 Hz, which works well but is noticeable if the LED is moving. In comparison, DotStars have a 20 KHz PWM rate, so even when moving the LED around, you won't see the pixelation, the blending is very smooth. (we recommend DotStars if you can use them!)

This is the 60 LED-per-meter version of our DotStar strips, on white flex PCB. We also have this in Warm White and RGB full color.

The strip is made of flexible PCB material, and comes with a weatherproof sheathing. You can cut this stuff pretty easily with wire cutters, there are cut-lines every 1 LED. Solder to the 0.1" copper pads and you're good to go. Of course, you can also connect strips together to make them longer, just watch how much current you need! We have a 5V 4A power supply that can drive a half meter or meter, a 5V/10A supply that can drive a couple meters (depending on use) You must use a 5V DC power supply to power these strips, do not use higher than 6V or you can destroy the entire strip

These strips come in 4 meter reels with a 4-pin JST SM connector on each end. These strips are sold by the meter! If you buy 4 meters at a time, you'll get full reels with two connectors. If you buy less than 4m, you'll get a single strip, but it will be a cut piece from a reel which may or may not have a connector on it. If the piece comes from the end of the reel, the connector may be on the output end of the strip!

To wire up these strips we suggest picking up some JST SM plug and receptacle cables for the signal wires  For the power wires, you will also probably want a 2.1mm DC jack to wire in so you can connect one of our 5V wall adapters to power it.

We have a tutorial showing wiring, power usage calculations, example code for usage, etc. Please check it out!

Move over NeoPixels, there's a new LED strip in town! These fancy new DotStar LED strips are a great upgrade for people who have loved and used NeoPixel strips for a few years but want something even better. DotStar LEDs use generic 2-wire SPI, so you can push data much faster than with the NeoPixel 800 KHz protocol and there's no specific timing required. They also have much higher PWM refresh rates, so  you can do Persistence-of-Vision (POV) and have less flickering, particularly at low brightness levels.

Make your own smart Cool White LED arrangement with the same integrated LED driver that is used in our DotStar or NeoPixel LED strips.  Unlit, the color resembles a yellow Starburst. Lit up these are insanely bright (like ow my eye hurts) and can be controlled with 24 bit high-frequency PWM. The phosphor helps diffuse the 3 white dies inside together for a very bright but consistant light, compared to what you get by trying to mix RGB to make white (which never quite looks right)

However, unlike NeoPixels, these LEDs have 2 wires (input and output) for sending data - one clock pin and one data pin. That means you need two pins, not one, to control DotStars. Because the clock and data is separated, you can use any processor speed or type to control these strips, and you don't have to worry about being careful with the timing. Hardware SPI support is handy but not required. This makes them excellent for use with any microcontroller or microprocessor, including Arduino, Raspberry Pi, BeagleBone, Propeller, SparkCore, and any 'raw' microcontrollers/microprocessors. It's very easy to port the library, and you can send data to the pixels at up to 32MHz clock rate!

NeoPixel LEDs use 800 KHz protocol so specific timing is required. On NeoPixels, the PWM rate is 400 Hz, which works well but is noticeable if the LED is moving. In comparison, DotStars have a 20 KHz PWM rate, so even when moving the LED around, you won't see the pixelation, the blending is very smooth. (we recommend DotStars if you can use them!)

This is the 30 LED-per-meter version of our DotStar strips, on white flex PCB. We also have this in Warm White and RGB full color.

The strip is made of flexible PCB material, and comes with a weatherproof sheathing. You can cut this stuff pretty easily with wire cutters, there are cut-lines every 1 LED. Solder to the 0.1" copper pads and you're good to go. Of course, you can also connect strips together to make them longer, just watch how much current you need! We have a 5V 4A power supply that can drive a half meter or meter, a 5V/10A supply that can drive a couple meters (depending on use) You must use a 5V DC power supply to power these strips, do not use higher than 6V or you can destroy the entire strip

These strips come in 5 meter reels with a 4-pin JST SM connector on each end. These strips are sold by the meter! If you buy 5 meters at a time, you'll get full reels with two connectors. If you buy less than 5m, you'll get a single strip, but it will be a cut piece from a reel which may or may not have a connector on it. If the piece comes from the end of the reel, the connector may be on the output end of the strip!

To wire up these strips we suggest picking up some JST SM plug and receptacle cables for the signal wires  For the power wires, you will also probably want a 2.1mm DC jack to wire in so you can connect one of our 5V wall adapters to power it.

We have a tutorial showing wiring, power usage calculations, example code for usage, etc. Please check it out!

Grove – LED Bar is comprised of a 10 segment LED gauge bar and an MY9221 LED controlling chip. It can be used as a indicator for remaining battery life, voltage, water level, music volume or other values that require a gradient display. There are 10 LED bars in the LED bar graph: one red, one yellow, one light green, and the rest green. Demo code is available to get you up and running quickly. It lights up the LEDs sequentially from red to green, so the entire bar graph is lit up in the end. Want to go further? Go ahead and code your own effect.

Features

Each LED segment can be controlled individually via code

Grove module

Plug-and-play

Can be cascaded for a larger display

Flexible power option, supports 3-5.5DC

Available demo code

A dream come true...an analog LED strip with both RGB and Warm White LEDs...It's so........bbbeeeaaaaauuuttttiiiifuuulllll!!!

These LED strips are fun and glowy. There are 60 RGB and Warm White LEDs per meter - you can control the entire strip at once with any microcontroller and three transistors. The way they are wired, you will need a 9-12VDC power supply and then ground the R/G/B/W pins to turn on the colors. Use any NPN or N-channel MOSFET (although the big powerful kind is good for a large strip) and PWM the inputs for color-mixing.

This is the 60 LED-per-meter RGB + Warm White version. We also have this in RGB + Cool White. We splurged and got the weatherproof kind with a white flexi PCB. Great for decorating your bike or art project, costuming or funky fashion.

For powering, a good 12V supply is key. The one we carry will do well for fixed installations. For portable use, we suggest a 8xAA battery holder

Please Note: these strips are weatherproof so they'll be more rugged than uncovered strips, but they not tested for long term submersion in water, especially chlorinated water, or exposed to UV (eg sunlight) for extended periods of time. They are for indoor use or light outdoor use without direct sun/water. That means you cannot put them into a pool, lake, aquarium, etc. The silk-screening and LED brightness of the strips may vary slightly from reel to reel

You can cut this stuff pretty easily with wire cutters, there are cut-lines every 5cm (3 LEDs each), and trim off the weatherproof cover. Solder to the 0.1" copper pads and you're good to go.

They come in 4 meter reels, and are sold by the meter! If you buy 4m at a time, you'll get full reels. If you buy less than 4m, you'll get a single strip, but it will be a cut piece from a reel which may or may not have a connector on it. If the piece comes from the end of the reel, the connector may be on the output end of the strip!

We have a full tutorial with details, diagrams, schematics and Arduino + CircuitPython code for using your RGBW LED strip, please check it out!

This is a simple pack of five White LilyPad LEDs that are still attached to one another, letting you snap the LEDs apart at your leisure to sew into clothing or whatever else you can dream up.

LilyPad is a wearable e-textile technology developed by Dr. Leah Buechley and cooperatively designed by Leah and SparkFun. Each LilyPad piece was creatively designed with large sew tabs to allow them to be sewn into fabric. Various input, output, power and sensor boards are available. They’re even washable (with special care)!

Note: A portion of this sale is given back to Dr. Buechley for continued development and education in e-textiles.

Features

5.5mm x 12.5mm

Thin 0.8mm PCB

Blink any color you need! Use the Tri-Color LED board as a simple indicator, or by pulsing the red, green, and blue channels, you can create any color. Very bright output. This is a common anode design - to turn on a channel you simply need to ground one of the R/G/B pins to illuminate that channel.

LilyPad is a wearable technology developed by Leah Buechley and cooperatively designed by Leah and SparkFun. Each LilyPad was creatively designed to have large connecting pads to allow them to be sewn into clothing. Various input, output, power, and sensor boards are available. They’re even washable!

Note: A portion of this sale is given back to Dr. Leah Buechley for continued development and education of e-textiles.

Get Started with the LilyPad Tri-Color LED Guide

Features

20mm outer diameter

Thin 0.8mm PCB

sensors

size(mm)

output

max current

optimalrange

LED

board

1

5.0 × 20.0

analog

3.5 mA

5 mA

10 mm

This IR LED/phototransistor pair is great for precisely identifying changes in reflectance (like line detection). It operates from 2.9 V to 5.5 V and offers dimmable brightness control independent of the supply voltage. In general, the closer the object, the higher the contrast between light and dark readings, but high-reflectance objects are generally detectable out to around 30 mm. This version features a high-performance, low-current QTRX sensor with lenses.

Pinout diagram of the QTRX/QTRXL-HD-01A Reflectance Sensor Array.

QTRX-HD-01A Reflectance Sensor, front and back views.

QTRX/QTRXL-HD-01A Reflectance Sensor dimensions.

Dimensions: 5.0 × 20.0 × 4.4 mm (see the dimension diagram (1MB pdf) for more details)

Operating voltage: 2.9 V to 5.5 V

Sensor type: QTRX

Sensor count: 1

Full-brightness LED current: 3.5 mA (independent of supply voltage)

Max board current: 5 mA

Output format: analog voltage (0 V to VCC)

Optimal sensing distance: 10 mm

Maximum recommended sensing distance: 30 mm

Weight: 0.25 g

These reflectance sensors feature a linear array of infrared emitter/phototransistor pair modules in a high-density (4 mm pitch) or medium-density (8 mm pitch) arrangement, which makes them well suited for applications that require detection of changes in reflectivity. This change in reflectivity can be due to a color change at a fixed distance, such as when sensing a black line on a white background, as well as due to a change in the distance to or presence of an object in front of the sensor. A variety of sensor counts and densities is available so you can pick the ideal arrangement for your application. Since the outputs are all independent, you can connect just some of the channels to attain an irregular or non-standard sensor spacing.

Unlike our original QTR sensor modules, these units have integrated LED drivers that provide brightness control independent of the supply voltage, which can be anywhere from 2.9 V to 5.5 V, while enabling optional dimming to any of 32 possible brightness settings. For high-density (HD) modules with five or more sensors and medium-density (MD) modules with eleven or more sensors, there are separate controls for the odd-numbered and even-numbered LEDs, which gives you extra options for detecting light reflected at various angles. See the “Emitter control” section below for more information on using this feature.

Two different sensor options are available, denoted by “QTR” or “QTRX” in the product name. The “QTR” versions feature lower-cost sensor modules without lenses while the “QTRX” versions feature higher-performance sensor modules with lenses, which allow similar performance at a much lower IR LED current. You can see the two different sensor styles in the pictures below of the 4-channel modules:

QTR-HD-04A Reflectance Sensor Array.

QTRX-HD-04RC Reflectance Sensor Array.

We also have several single-channel modules with the “QTRXL” designator that offer extra-long range by using the QTRX-style sensor module with higher current through the emitter.

Each sensor option is available in two output types: an “A” version with analog voltage outputs between 0 V and VCC, and an “RC” version with outputs that can be read with a digital I/O line on a microcontroller by first setting the lines high and then releasing them and timing how long it takes them to read as low (typically anywhere from a few microseconds to a few milliseconds). The lower the output voltage or shorter the voltage decay time, the higher the reflectance. The following simplified schematic diagrams show the circuits for the individual channels:

Schematic diagrams of individual QTR sensor channels for A version (left) and RC version (right). This applies only to the newer QTRs with dimmable emitters.

Our Arduino library makes it easy to use these sensor modules with an Arduino or compatible controller by providing methods for controlling the emitters, calibrating the module, and reading the individual sensor values from either the A or RC versions. It also has a method specifically for line-following applications to compute the location of the line under the array.

Note: Unlike most of our products, these sensor arrays do not ship with any headers or connectors included, so you will need to supply your own or solder wires directly to the board to use it. See our selection of male headers, female headers, and pre-crimped wires for various connector options.

Each sensor on the A versions outputs its reflectance measurement as an analog voltage that can range from 0 V when the reflectance is very strong to VCC when the reflectance is very weak. The typical sequence for reading a sensor is:

Use a microcontroller’s analog-to-digital converter (ADC) to measure the voltages.

Use a comparator with an adjustable threshold to convert each analog voltage into a digital (i.e. black/white) signal that can be read by the digital I/O line of a microcontroller.

Connect each output directly to a digital I/O line of a microcontroller and rely upon its logic threshold.

This last method will work if you are able to get high reflectance from your white surface as depicted in the left image, but will probably fail if you have a lower-reflectance signal profile like the one on the right.

QTR-1A output 1/8" away from a spinning white disk with a black line on it.

QTR-1A output 3/8" away from a spinning white disk with a black line on it.

Each sensor on the RC versions requires a digital I/O line capable of driving the output line high and then measuring the time for the output voltage to decay. The typical sequence for reading a sensor is:

QTR-1RC output (yellow) when 1/8" above a black line and microcontroller timing of that output (blue).

QTR-1RC output (yellow) when 1/8" above a white surface and microcontroller timing of that output (blue).

Turn on IR LEDs (optional).

Set the I/O line to an output and drive it high.

Allow at least 10 μs for the sensor output to rise.

Make the I/O line an input (high impedance).

Measure the time for the voltage to decay by waiting for the I/O line to go low.

Turn off IR LEDs (optional).

These steps can typically be executed in parallel on multiple I/O lines.

With a strong reflectance, the decay time can be as low as a few microseconds; with no reflectance, the decay time can be up to a few milliseconds. The exact time of the decay depends on your microcontroller’s I/O line characteristics. Meaningful results can be available within 1 ms in typical cases (i.e. when not trying to measure subtle differences in low-reflectance scenarios), allowing up to 1 kHz sampling of all sensors. If lower-frequency sampling is sufficient, you can achieve substantial power savings by turning off the LEDs. For example, if a 100 Hz sampling rate is acceptable, the LEDs can be off 90% of the time, lowering average current consumption from 125 mA to 13 mA.

These reflectance sensor arrays maintain a constant current through their IR emitters, keeping the emitters’ brightness constant, independent of the supply voltage (2.9 V to 5.5 V). The emitters can be controlled with the board’s CTRL pins, and the details of the control depends on the array size and density:

HD units with 5 or more sensors and MD units with 11 or more sensors have two emitter control pins: CTRL ODD and CTRL EVEN. By default, these are connected together with a 1 kΩ resistor and pulled up, turning on all the emitters by default and allowing them to be controlled with a signal on either pin, but the CTRL ODD and CTRL EVEN pins can be driven separately for independent control of the odd-numbered and even-numbered emitters.

MD units with 3-10 sensors also have two emitter control pins since these are made by only populating every other sensor on an HD board, but only the CTRL ODD pin will have an effect on these versions (it is not possible to independently control alternate emitters).

HD units with 4 or fewer sensors and MD units with 2 or fewer sensors have a single CTRL pin that controls all of the emitters.

Driving a CTRL pin low for at least 1 ms turns off the associated emitter LEDs, while driving it high (or allowing the board to pull it high) turns on the emitters with the board’s default (full) current, which is 30 mA for “QTR” versions and 3.5 mA for “QTRX” versions. For more advanced use, the CTRL pin can be pulsed low to cycle the associated emitters through 32 dimming levels.

Demo of IR LED dimming and independent even/odd control on the QTR-HD-07x (as seen through an old digital camera that can see IR).

Demo of IR LED dimming and independent even/odd control on the QTRX-HD-07x (as seen through an old digital camera that can see IR).

To send a pulse, you should drive the CTRL pin low for at least 0.5 μs (but no more than 300 μs), then high for at least 0.5 μs; (it should remain high after the last pulse). Each pulse causes the driver to advance to the next dimming level, wrapping around to 100% after the lowest-current level. Each dimming level corresponds to a 3.33% reduction in current, except for the last three levels, which represent a 1.67% reduction, as shown in the table below. Note that turning the LEDs off with a >1 ms pulse and then back on resets them to full current.

For example, to reduce the emitter current to 50%, you would apply 15 low pulses to the CTRL pin and then keep it high after the last pulse.

pitch × sensors

size(mm)

output

max current

optimalrange

LED

board

4 mm × 9

37.0 × 20.0

analog

3.5 mA

22 mA

10 mm

This array of IR LED/phototransistor pairs is great for precisely identifying changes in reflectance (like line detection). It operates from 2.9 V to 5.5 V and offers dimmable brightness control independent of the supply voltage and separate controls for the odd and even emitters. In general, the closer the object, the higher the contrast between light and dark readings, but high-reflectance objects are generally detectable out to around 40 mm. This version features high-performance, low-current QTRX sensors with lenses.

Pinout diagram of a QTRX-HD-xA Reflectance Sensor Array.

QTRX-HD-09A Reflectance Sensor Array, front and back views.

QTRX-HD-09A Reflectance Sensor Array, front and back views.

Dimensions: 37.0 × 20.0 × 3.0 mm (see the dimension diagram (1MB pdf) for more details)

Operating voltage: 2.9 V to 5.5 V

Sensor type: QTRX

Sensor count: 9

Sensor pitch: 4 mm

Full-brightness LED current: 3.5 mA (independent of supply voltage)

Max board current: 22 mA

Output format: analog voltages (0 V to VCC)

Optimal sensing distance: 10 mm

Maximum recommended sensing distance: 40 mm

Weight: 2.1 g

These reflectance sensors feature a linear array of infrared emitter/phototransistor pair modules in a high-density (4 mm pitch) or medium-density (8 mm pitch) arrangement, which makes them well suited for applications that require detection of changes in reflectivity. This change in reflectivity can be due to a color change at a fixed distance, such as when sensing a black line on a white background, as well as due to a change in the distance to or presence of an object in front of the sensor. A variety of sensor counts and densities is available so you can pick the ideal arrangement for your application. Since the outputs are all independent, you can connect just some of the channels to attain an irregular or non-standard sensor spacing.

Unlike our original QTR sensor modules, these units have integrated LED drivers that provide brightness control independent of the supply voltage, which can be anywhere from 2.9 V to 5.5 V, while enabling optional dimming to any of 32 possible brightness settings. For high-density (HD) modules with five or more sensors and medium-density (MD) modules with eleven or more sensors, there are separate controls for the odd-numbered and even-numbered LEDs, which gives you extra options for detecting light reflected at various angles. See the “Emitter control” section below for more information on using this feature.

Two different sensor options are available, denoted by “QTR” or “QTRX” in the product name. The “QTR” versions feature lower-cost sensor modules without lenses while the “QTRX” versions feature higher-performance sensor modules with lenses, which allow similar performance at a much lower IR LED current. You can see the two different sensor styles in the pictures below of the 4-channel modules:

QTR-HD-04A Reflectance Sensor Array.

QTRX-HD-04RC Reflectance Sensor Array.

We also have several single-channel modules with the “QTRXL” designator that offer extra-long range by using the QTRX-style sensor module with higher current through the emitter.

Each sensor option is available in two output types: an “A” version with analog voltage outputs between 0 V and VCC, and an “RC” version with outputs that can be read with a digital I/O line on a microcontroller by first setting the lines high and then releasing them and timing how long it takes them to read as low (typically anywhere from a few microseconds to a few milliseconds). The lower the output voltage or shorter the voltage decay time, the higher the reflectance. The following simplified schematic diagrams show the circuits for the individual channels:

Schematic diagrams of individual QTR sensor channels for A version (left) and RC version (right). This applies only to the newer QTRs with dimmable emitters.

Our Arduino library makes it easy to use these sensor modules with an Arduino or compatible controller by providing methods for controlling the emitters, calibrating the module, and reading the individual sensor values from either the A or RC versions. It also has a method specifically for line-following applications to compute the location of the line under the array.

Note: Unlike most of our products, these sensor arrays do not ship with any headers or connectors included, so you will need to supply your own or solder wires directly to the board to use it. See our selection of male headers, female headers, and pre-crimped wires for various connector options.

Each sensor on the A versions outputs its reflectance measurement as an analog voltage that can range from 0 V when the reflectance is very strong to VCC when the reflectance is very weak. The typical sequence for reading a sensor is:

Use a microcontroller’s analog-to-digital converter (ADC) to measure the voltages.

Use a comparator with an adjustable threshold to convert each analog voltage into a digital (i.e. black/white) signal that can be read by the digital I/O line of a microcontroller.

Connect each output directly to a digital I/O line of a microcontroller and rely upon its logic threshold.

This last method will work if you are able to get high reflectance from your white surface as depicted in the left image, but will probably fail if you have a lower-reflectance signal profile like the one on the right.

QTR-1A output 1/8" away from a spinning white disk with a black line on it.

QTR-1A output 3/8" away from a spinning white disk with a black line on it.

Each sensor on the RC versions requires a digital I/O line capable of driving the output line high and then measuring the time for the output voltage to decay. The typical sequence for reading a sensor is:

QTR-1RC output (yellow) when 1/8" above a black line and microcontroller timing of that output (blue).

QTR-1RC output (yellow) when 1/8" above a white surface and microcontroller timing of that output (blue).

Turn on IR LEDs (optional).

Set the I/O line to an output and drive it high.

Allow at least 10 μs for the sensor output to rise.

Make the I/O line an input (high impedance).

Measure the time for the voltage to decay by waiting for the I/O line to go low.

Turn off IR LEDs (optional).

These steps can typically be executed in parallel on multiple I/O lines.

With a strong reflectance, the decay time can be as low as a few microseconds; with no reflectance, the decay time can be up to a few milliseconds. The exact time of the decay depends on your microcontroller’s I/O line characteristics. Meaningful results can be available within 1 ms in typical cases (i.e. when not trying to measure subtle differences in low-reflectance scenarios), allowing up to 1 kHz sampling of all sensors. If lower-frequency sampling is sufficient, you can achieve substantial power savings by turning off the LEDs. For example, if a 100 Hz sampling rate is acceptable, the LEDs can be off 90% of the time, lowering average current consumption from 125 mA to 13 mA.

These reflectance sensor arrays maintain a constant current through their IR emitters, keeping the emitters’ brightness constant, independent of the supply voltage (2.9 V to 5.5 V). The emitters can be controlled with the board’s CTRL pins, and the details of the control depends on the array size and density:

HD units with 5 or more sensors and MD units with 11 or more sensors have two emitter control pins: CTRL ODD and CTRL EVEN. By default, these are connected together with a 1 kΩ resistor and pulled up, turning on all the emitters by default and allowing them to be controlled with a signal on either pin, but the CTRL ODD and CTRL EVEN pins can be driven separately for independent control of the odd-numbered and even-numbered emitters.

MD units with 3-10 sensors also have two emitter control pins since these are made by only populating every other sensor on an HD board, but only the CTRL ODD pin will have an effect on these versions (it is not possible to independently control alternate emitters).

HD units with 4 or fewer sensors and MD units with 2 or fewer sensors have a single CTRL pin that controls all of the emitters.

Driving a CTRL pin low for at least 1 ms turns off the associated emitter LEDs, while driving it high (or allowing the board to pull it high) turns on the emitters with the board’s default (full) current, which is 30 mA for “QTR” versions and 3.5 mA for “QTRX” versions. For more advanced use, the CTRL pin can be pulsed low to cycle the associated emitters through 32 dimming levels.

Demo of IR LED dimming and independent even/odd control on the QTR-HD-07x (as seen through an old digital camera that can see IR).

Demo of IR LED dimming and independent even/odd control on the QTRX-HD-07x (as seen through an old digital camera that can see IR).

To send a pulse, you should drive the CTRL pin low for at least 0.5 μs (but no more than 300 μs), then high for at least 0.5 μs; (it should remain high after the last pulse). Each pulse causes the driver to advance to the next dimming level, wrapping around to 100% after the lowest-current level. Each dimming level corresponds to a 3.33% reduction in current, except for the last three levels, which represent a 1.67% reduction, as shown in the table below. Note that turning the LEDs off with a >1 ms pulse and then back on resets them to full current.

For example, to reduce the emitter current to 50%, you would apply 15 low pulses to the CTRL pin and then keep it high after the last pulse.

pitch × sensors

size(mm)

output

max current

optimalrange

LED

board

8 mm × 5

37.0 × 20.0

RC (digital)

3.5 mA

14 mA

10 mm

This array of IR LED/phototransistor pairs is great for precisely identifying changes in reflectance (like line detection). It operates from 2.9 V to 5.5 V and offers dimmable brightness control independent of the supply voltage. In general, the closer the object, the higher the contrast between light and dark readings, but high-reflectance objects are generally detectable out to around 40 mm. This version features high-performance, low-current QTRX sensors with lenses.

Pinout diagram of a QTRX-MD-xRC Reflectance Sensor Array.

QTRX-MD-05RC Reflectance Sensor Array, front and back views.

QTRX-MD-05RC Reflectance Sensor Array dimensions.

Dimensions: 37.0 × 20.0 × 3.0 mm (see the dimension diagram (1MB pdf) for more details)

Operating voltage: 2.9 V to 5.5 V

Sensor type: QTRX

Sensor count: 5

Sensor pitch: 8 mm

Full-brightness LED current: 3.5 mA (independent of supply voltage)

Max board current: 14 mA

Output format: digital I/O-compatible signals that can be read in parallel as timed high pulses

Optimal sensing distance: 10 mm

Maximum recommended sensing distance: 40 mm

Weight: 1.9 g

These reflectance sensors feature a linear array of infrared emitter/phototransistor pair modules in a high-density (4 mm pitch) or medium-density (8 mm pitch) arrangement, which makes them well suited for applications that require detection of changes in reflectivity. This change in reflectivity can be due to a color change at a fixed distance, such as when sensing a black line on a white background, as well as due to a change in the distance to or presence of an object in front of the sensor. A variety of sensor counts and densities is available so you can pick the ideal arrangement for your application. Since the outputs are all independent, you can connect just some of the channels to attain an irregular or non-standard sensor spacing.

Unlike our original QTR sensor modules, these units have integrated LED drivers that provide brightness control independent of the supply voltage, which can be anywhere from 2.9 V to 5.5 V, while enabling optional dimming to any of 32 possible brightness settings. For high-density (HD) modules with five or more sensors and medium-density (MD) modules with eleven or more sensors, there are separate controls for the odd-numbered and even-numbered LEDs, which gives you extra options for detecting light reflected at various angles. See the “Emitter control” section below for more information on using this feature.

Two different sensor options are available, denoted by “QTR” or “QTRX” in the product name. The “QTR” versions feature lower-cost sensor modules without lenses while the “QTRX” versions feature higher-performance sensor modules with lenses, which allow similar performance at a much lower IR LED current. You can see the two different sensor styles in the pictures below of the 4-channel modules:

QTR-HD-04A Reflectance Sensor Array.

QTRX-HD-04RC Reflectance Sensor Array.

We also have several single-channel modules with the “QTRXL” designator that offer extra-long range by using the QTRX-style sensor module with higher current through the emitter.

Each sensor option is available in two output types: an “A” version with analog voltage outputs between 0 V and VCC, and an “RC” version with outputs that can be read with a digital I/O line on a microcontroller by first setting the lines high and then releasing them and timing how long it takes them to read as low (typically anywhere from a few microseconds to a few milliseconds). The lower the output voltage or shorter the voltage decay time, the higher the reflectance. The following simplified schematic diagrams show the circuits for the individual channels:

Schematic diagrams of individual QTR sensor channels for A version (left) and RC version (right). This applies only to the newer QTRs with dimmable emitters.

Our Arduino library makes it easy to use these sensor modules with an Arduino or compatible controller by providing methods for controlling the emitters, calibrating the module, and reading the individual sensor values from either the A or RC versions. It also has a method specifically for line-following applications to compute the location of the line under the array.

Note: Unlike most of our products, these sensor arrays do not ship with any headers or connectors included, so you will need to supply your own or solder wires directly to the board to use it. See our selection of male headers, female headers, and pre-crimped wires for various connector options.

Each sensor on the A versions outputs its reflectance measurement as an analog voltage that can range from 0 V when the reflectance is very strong to VCC when the reflectance is very weak. The typical sequence for reading a sensor is:

Use a microcontroller’s analog-to-digital converter (ADC) to measure the voltages.

Use a comparator with an adjustable threshold to convert each analog voltage into a digital (i.e. black/white) signal that can be read by the digital I/O line of a microcontroller.

Connect each output directly to a digital I/O line of a microcontroller and rely upon its logic threshold.

This last method will work if you are able to get high reflectance from your white surface as depicted in the left image, but will probably fail if you have a lower-reflectance signal profile like the one on the right.

QTR-1A output 1/8" away from a spinning white disk with a black line on it.

QTR-1A output 3/8" away from a spinning white disk with a black line on it.

Each sensor on the RC versions requires a digital I/O line capable of driving the output line high and then measuring the time for the output voltage to decay. The typical sequence for reading a sensor is:

QTR-1RC output (yellow) when 1/8" above a black line and microcontroller timing of that output (blue).

QTR-1RC output (yellow) when 1/8" above a white surface and microcontroller timing of that output (blue).

Turn on IR LEDs (optional).

Set the I/O line to an output and drive it high.

Allow at least 10 μs for the sensor output to rise.

Make the I/O line an input (high impedance).

Measure the time for the voltage to decay by waiting for the I/O line to go low.

Turn off IR LEDs (optional).

These steps can typically be executed in parallel on multiple I/O lines.

With a strong reflectance, the decay time can be as low as a few microseconds; with no reflectance, the decay time can be up to a few milliseconds. The exact time of the decay depends on your microcontroller’s I/O line characteristics. Meaningful results can be available within 1 ms in typical cases (i.e. when not trying to measure subtle differences in low-reflectance scenarios), allowing up to 1 kHz sampling of all sensors. If lower-frequency sampling is sufficient, you can achieve substantial power savings by turning off the LEDs. For example, if a 100 Hz sampling rate is acceptable, the LEDs can be off 90% of the time, lowering average current consumption from 125 mA to 13 mA.

These reflectance sensor arrays maintain a constant current through their IR emitters, keeping the emitters’ brightness constant, independent of the supply voltage (2.9 V to 5.5 V). The emitters can be controlled with the board’s CTRL pins, and the details of the control depends on the array size and density:

HD units with 5 or more sensors and MD units with 11 or more sensors have two emitter control pins: CTRL ODD and CTRL EVEN. By default, these are connected together with a 1 kΩ resistor and pulled up, turning on all the emitters by default and allowing them to be controlled with a signal on either pin, but the CTRL ODD and CTRL EVEN pins can be driven separately for independent control of the odd-numbered and even-numbered emitters.

MD units with 3-10 sensors also have two emitter control pins since these are made by only populating every other sensor on an HD board, but only the CTRL ODD pin will have an effect on these versions (it is not possible to independently control alternate emitters).

HD units with 4 or fewer sensors and MD units with 2 or fewer sensors have a single CTRL pin that controls all of the emitters.

Driving a CTRL pin low for at least 1 ms turns off the associated emitter LEDs, while driving it high (or allowing the board to pull it high) turns on the emitters with the board’s default (full) current, which is 30 mA for “QTR” versions and 3.5 mA for “QTRX” versions. For more advanced use, the CTRL pin can be pulsed low to cycle the associated emitters through 32 dimming levels.

Demo of IR LED dimming and independent even/odd control on the QTR-HD-07x (as seen through an old digital camera that can see IR).

Demo of IR LED dimming and independent even/odd control on the QTRX-HD-07x (as seen through an old digital camera that can see IR).

To send a pulse, you should drive the CTRL pin low for at least 0.5 μs (but no more than 300 μs), then high for at least 0.5 μs; (it should remain high after the last pulse). Each pulse causes the driver to advance to the next dimming level, wrapping around to 100% after the lowest-current level. Each dimming level corresponds to a 3.33% reduction in current, except for the last three levels, which represent a 1.67% reduction, as shown in the table below. Note that turning the LEDs off with a >1 ms pulse and then back on resets them to full current.

For example, to reduce the emitter current to 50%, you would apply 15 low pulses to the CTRL pin and then keep it high after the last pulse.

sensors

size(mm)

output

max current

optimalrange

LED

board

1

5.0 × 20.0

analog

30 mA

32 mA

5 mm

This IR LED/phototransistor pair is great for precisely identifying changes in reflectance (like line detection). It operates from 2.9 V to 5.5 V and offers dimmable brightness control independent of the supply voltage. In general, the closer the object, the higher the contrast between light and dark readings, but high-reflectance objects are generally detectable out to around 30 mm. This version features a traditional-style QTR sensor without lenses.

Pinout diagram of the QTR-HD-01A Reflectance Sensor Array.

QTR-HD-01A Reflectance Sensor, front and back views.

QTR-HD-01A Reflectance Sensor dimensions.

Dimensions: 5.0 × 20.0 × 3.9 mm (see the dimension diagram (1MB pdf) for more details)

Operating voltage: 2.9 V to 5.5 V

Sensor type: QTR

Sensor count: 1

Full-brightness LED current: 30 mA (independent of supply voltage)

Max board current: 32 mA

Output format: analog voltage (0 V to VCC)

Optimal sensing distance: 5 mm

Maximum recommended sensing distance: 30 mm

Weight: 0.25 g

These reflectance sensors feature a linear array of infrared emitter/phototransistor pair modules in a high-density (4 mm pitch) or medium-density (8 mm pitch) arrangement, which makes them well suited for applications that require detection of changes in reflectivity. This change in reflectivity can be due to a color change at a fixed distance, such as when sensing a black line on a white background, as well as due to a change in the distance to or presence of an object in front of the sensor. A variety of sensor counts and densities is available so you can pick the ideal arrangement for your application. Since the outputs are all independent, you can connect just some of the channels to attain an irregular or non-standard sensor spacing.

Unlike our original QTR sensor modules, these units have integrated LED drivers that provide brightness control independent of the supply voltage, which can be anywhere from 2.9 V to 5.5 V, while enabling optional dimming to any of 32 possible brightness settings. For high-density (HD) modules with five or more sensors and medium-density (MD) modules with eleven or more sensors, there are separate controls for the odd-numbered and even-numbered LEDs, which gives you extra options for detecting light reflected at various angles. See the “Emitter control” section below for more information on using this feature.

Two different sensor options are available, denoted by “QTR” or “QTRX” in the product name. The “QTR” versions feature lower-cost sensor modules without lenses while the “QTRX” versions feature higher-performance sensor modules with lenses, which allow similar performance at a much lower IR LED current. You can see the two different sensor styles in the pictures below of the 4-channel modules:

QTR-HD-04A Reflectance Sensor Array.

QTRX-HD-04RC Reflectance Sensor Array.

We also have several single-channel modules with the “QTRXL” designator that offer extra-long range by using the QTRX-style sensor module with higher current through the emitter.

Each sensor option is available in two output types: an “A” version with analog voltage outputs between 0 V and VCC, and an “RC” version with outputs that can be read with a digital I/O line on a microcontroller by first setting the lines high and then releasing them and timing how long it takes them to read as low (typically anywhere from a few microseconds to a few milliseconds). The lower the output voltage or shorter the voltage decay time, the higher the reflectance. The following simplified schematic diagrams show the circuits for the individual channels:

Schematic diagrams of individual QTR sensor channels for A version (left) and RC version (right). This applies only to the newer QTRs with dimmable emitters.

Our Arduino library makes it easy to use these sensor modules with an Arduino or compatible controller by providing methods for controlling the emitters, calibrating the module, and reading the individual sensor values from either the A or RC versions. It also has a method specifically for line-following applications to compute the location of the line under the array.

Note: Unlike most of our products, these sensor arrays do not ship with any headers or connectors included, so you will need to supply your own or solder wires directly to the board to use it. See our selection of male headers, female headers, and pre-crimped wires for various connector options.

Each sensor on the A versions outputs its reflectance measurement as an analog voltage that can range from 0 V when the reflectance is very strong to VCC when the reflectance is very weak. The typical sequence for reading a sensor is:

Use a microcontroller’s analog-to-digital converter (ADC) to measure the voltages.

Use a comparator with an adjustable threshold to convert each analog voltage into a digital (i.e. black/white) signal that can be read by the digital I/O line of a microcontroller.

Connect each output directly to a digital I/O line of a microcontroller and rely upon its logic threshold.

This last method will work if you are able to get high reflectance from your white surface as depicted in the left image, but will probably fail if you have a lower-reflectance signal profile like the one on the right.

QTR-1A output 1/8" away from a spinning white disk with a black line on it.

QTR-1A output 3/8" away from a spinning white disk with a black line on it.

Each sensor on the RC versions requires a digital I/O line capable of driving the output line high and then measuring the time for the output voltage to decay. The typical sequence for reading a sensor is:

QTR-1RC output (yellow) when 1/8" above a black line and microcontroller timing of that output (blue).

QTR-1RC output (yellow) when 1/8" above a white surface and microcontroller timing of that output (blue).

Turn on IR LEDs (optional).

Set the I/O line to an output and drive it high.

Allow at least 10 μs for the sensor output to rise.

Make the I/O line an input (high impedance).

Measure the time for the voltage to decay by waiting for the I/O line to go low.

Turn off IR LEDs (optional).

These steps can typically be executed in parallel on multiple I/O lines.

With a strong reflectance, the decay time can be as low as a few microseconds; with no reflectance, the decay time can be up to a few milliseconds. The exact time of the decay depends on your microcontroller’s I/O line characteristics. Meaningful results can be available within 1 ms in typical cases (i.e. when not trying to measure subtle differences in low-reflectance scenarios), allowing up to 1 kHz sampling of all sensors. If lower-frequency sampling is sufficient, you can achieve substantial power savings by turning off the LEDs. For example, if a 100 Hz sampling rate is acceptable, the LEDs can be off 90% of the time, lowering average current consumption from 125 mA to 13 mA.

These reflectance sensor arrays maintain a constant current through their IR emitters, keeping the emitters’ brightness constant, independent of the supply voltage (2.9 V to 5.5 V). The emitters can be controlled with the board’s CTRL pins, and the details of the control depends on the array size and density:

HD units with 5 or more sensors and MD units with 11 or more sensors have two emitter control pins: CTRL ODD and CTRL EVEN. By default, these are connected together with a 1 kΩ resistor and pulled up, turning on all the emitters by default and allowing them to be controlled with a signal on either pin, but the CTRL ODD and CTRL EVEN pins can be driven separately for independent control of the odd-numbered and even-numbered emitters.

MD units with 3-10 sensors also have two emitter control pins since these are made by only populating every other sensor on an HD board, but only the CTRL ODD pin will have an effect on these versions (it is not possible to independently control alternate emitters).

HD units with 4 or fewer sensors and MD units with 2 or fewer sensors have a single CTRL pin that controls all of the emitters.

Driving a CTRL pin low for at least 1 ms turns off the associated emitter LEDs, while driving it high (or allowing the board to pull it high) turns on the emitters with the board’s default (full) current, which is 30 mA for “QTR” versions and 3.5 mA for “QTRX” versions. For more advanced use, the CTRL pin can be pulsed low to cycle the associated emitters through 32 dimming levels.

Demo of IR LED dimming and independent even/odd control on the QTR-HD-07x (as seen through an old digital camera that can see IR).

Demo of IR LED dimming and independent even/odd control on the QTRX-HD-07x (as seen through an old digital camera that can see IR).

To send a pulse, you should drive the CTRL pin low for at least 0.5 μs (but no more than 300 μs), then high for at least 0.5 μs; (it should remain high after the last pulse). Each pulse causes the driver to advance to the next dimming level, wrapping around to 100% after the lowest-current level. Each dimming level corresponds to a 3.33% reduction in current, except for the last three levels, which represent a 1.67% reduction, as shown in the table below. Note that turning the LEDs off with a >1 ms pulse and then back on resets them to full current.

For example, to reduce the emitter current to 50%, you would apply 15 low pulses to the CTRL pin and then keep it high after the last pulse.

People often buy this product together with:

sensors

size(mm)

output

max current

optimalrange

LED

board

1

5.0 × 20.0

RC (digital)

30 mA

32 mA

5 mm

This IR LED/phototransistor pair is great for precisely identifying changes in reflectance (like line detection). It operates from 2.9 V to 5.5 V and offers dimmable brightness control independent of the supply voltage. In general, the closer the object, the higher the contrast between light and dark readings, but high-reflectance objects are generally detectable out to around 30 mm. This version features a traditional-style QTR sensor without lenses.

Pinout diagram of the QTR-HD-01RC Reflectance Sensor Array.

QTR-HD-01RC Reflectance Sensor, front and back views.

QTR-HD-01RC Reflectance Sensor dimensions.

Dimensions: 5.0 × 20.0 × 3.9 mm (see the dimension diagram (1MB pdf) for more details)

Operating voltage: 2.9 V to 5.5 V

Sensor type: QTR

Sensor count: 1

Full-brightness LED current: 30 mA (independent of supply voltage)

Max board current: 32 mA

Output format: digital I/O-compatible signal that can be read as a timed high pulse

Optimal sensing distance: 5 mm

Maximum recommended sensing distance: 30 mm

Weight: 0.25 g

These reflectance sensors feature a linear array of infrared emitter/phototransistor pair modules in a high-density (4 mm pitch) or medium-density (8 mm pitch) arrangement, which makes them well suited for applications that require detection of changes in reflectivity. This change in reflectivity can be due to a color change at a fixed distance, such as when sensing a black line on a white background, as well as due to a change in the distance to or presence of an object in front of the sensor. A variety of sensor counts and densities is available so you can pick the ideal arrangement for your application. Since the outputs are all independent, you can connect just some of the channels to attain an irregular or non-standard sensor spacing.

Unlike our original QTR sensor modules, these units have integrated LED drivers that provide brightness control independent of the supply voltage, which can be anywhere from 2.9 V to 5.5 V, while enabling optional dimming to any of 32 possible brightness settings. For high-density (HD) modules with five or more sensors and medium-density (MD) modules with eleven or more sensors, there are separate controls for the odd-numbered and even-numbered LEDs, which gives you extra options for detecting light reflected at various angles. See the “Emitter control” section below for more information on using this feature.

Two different sensor options are available, denoted by “QTR” or “QTRX” in the product name. The “QTR” versions feature lower-cost sensor modules without lenses while the “QTRX” versions feature higher-performance sensor modules with lenses, which allow similar performance at a much lower IR LED current. You can see the two different sensor styles in the pictures below of the 4-channel modules:

QTR-HD-04A Reflectance Sensor Array.

QTRX-HD-04RC Reflectance Sensor Array.

We also have several single-channel modules with the “QTRXL” designator that offer extra-long range by using the QTRX-style sensor module with higher current through the emitter.

Each sensor option is available in two output types: an “A” version with analog voltage outputs between 0 V and VCC, and an “RC” version with outputs that can be read with a digital I/O line on a microcontroller by first setting the lines high and then releasing them and timing how long it takes them to read as low (typically anywhere from a few microseconds to a few milliseconds). The lower the output voltage or shorter the voltage decay time, the higher the reflectance. The following simplified schematic diagrams show the circuits for the individual channels:

Schematic diagrams of individual QTR sensor channels for A version (left) and RC version (right). This applies only to the newer QTRs with dimmable emitters.

Our Arduino library makes it easy to use these sensor modules with an Arduino or compatible controller by providing methods for controlling the emitters, calibrating the module, and reading the individual sensor values from either the A or RC versions. It also has a method specifically for line-following applications to compute the location of the line under the array.

Note: Unlike most of our products, these sensor arrays do not ship with any headers or connectors included, so you will need to supply your own or solder wires directly to the board to use it. See our selection of male headers, female headers, and pre-crimped wires for various connector options.

Each sensor on the A versions outputs its reflectance measurement as an analog voltage that can range from 0 V when the reflectance is very strong to VCC when the reflectance is very weak. The typical sequence for reading a sensor is:

Use a microcontroller’s analog-to-digital converter (ADC) to measure the voltages.

Use a comparator with an adjustable threshold to convert each analog voltage into a digital (i.e. black/white) signal that can be read by the digital I/O line of a microcontroller.

Connect each output directly to a digital I/O line of a microcontroller and rely upon its logic threshold.

This last method will work if you are able to get high reflectance from your white surface as depicted in the left image, but will probably fail if you have a lower-reflectance signal profile like the one on the right.

QTR-1A output 1/8" away from a spinning white disk with a black line on it.

QTR-1A output 3/8" away from a spinning white disk with a black line on it.

Each sensor on the RC versions requires a digital I/O line capable of driving the output line high and then measuring the time for the output voltage to decay. The typical sequence for reading a sensor is:

QTR-1RC output (yellow) when 1/8" above a black line and microcontroller timing of that output (blue).

QTR-1RC output (yellow) when 1/8" above a white surface and microcontroller timing of that output (blue).

Turn on IR LEDs (optional).

Set the I/O line to an output and drive it high.

Allow at least 10 μs for the sensor output to rise.

Make the I/O line an input (high impedance).

Measure the time for the voltage to decay by waiting for the I/O line to go low.

Turn off IR LEDs (optional).

These steps can typically be executed in parallel on multiple I/O lines.

With a strong reflectance, the decay time can be as low as a few microseconds; with no reflectance, the decay time can be up to a few milliseconds. The exact time of the decay depends on your microcontroller’s I/O line characteristics. Meaningful results can be available within 1 ms in typical cases (i.e. when not trying to measure subtle differences in low-reflectance scenarios), allowing up to 1 kHz sampling of all sensors. If lower-frequency sampling is sufficient, you can achieve substantial power savings by turning off the LEDs. For example, if a 100 Hz sampling rate is acceptable, the LEDs can be off 90% of the time, lowering average current consumption from 125 mA to 13 mA.

These reflectance sensor arrays maintain a constant current through their IR emitters, keeping the emitters’ brightness constant, independent of the supply voltage (2.9 V to 5.5 V). The emitters can be controlled with the board’s CTRL pins, and the details of the control depends on the array size and density:

HD units with 5 or more sensors and MD units with 11 or more sensors have two emitter control pins: CTRL ODD and CTRL EVEN. By default, these are connected together with a 1 kΩ resistor and pulled up, turning on all the emitters by default and allowing them to be controlled with a signal on either pin, but the CTRL ODD and CTRL EVEN pins can be driven separately for independent control of the odd-numbered and even-numbered emitters.

MD units with 3-10 sensors also have two emitter control pins since these are made by only populating every other sensor on an HD board, but only the CTRL ODD pin will have an effect on these versions (it is not possible to independently control alternate emitters).

HD units with 4 or fewer sensors and MD units with 2 or fewer sensors have a single CTRL pin that controls all of the emitters.

Driving a CTRL pin low for at least 1 ms turns off the associated emitter LEDs, while driving it high (or allowing the board to pull it high) turns on the emitters with the board’s default (full) current, which is 30 mA for “QTR” versions and 3.5 mA for “QTRX” versions. For more advanced use, the CTRL pin can be pulsed low to cycle the associated emitters through 32 dimming levels.

Demo of IR LED dimming and independent even/odd control on the QTR-HD-07x (as seen through an old digital camera that can see IR).

Demo of IR LED dimming and independent even/odd control on the QTRX-HD-07x (as seen through an old digital camera that can see IR).

To send a pulse, you should drive the CTRL pin low for at least 0.5 μs (but no more than 300 μs), then high for at least 0.5 μs; (it should remain high after the last pulse). Each pulse causes the driver to advance to the next dimming level, wrapping around to 100% after the lowest-current level. Each dimming level corresponds to a 3.33% reduction in current, except for the last three levels, which represent a 1.67% reduction, as shown in the table below. Note that turning the LEDs off with a >1 ms pulse and then back on resets them to full current.

For example, to reduce the emitter current to 50%, you would apply 15 low pulses to the CTRL pin and then keep it high after the last pulse.

People often buy this product together with:

sensors

size(mm)

output

max current

optimalrange

LED

board

1

5.0 × 20.0

RC (digital)

3.5 mA

5 mA

10 mm

This IR LED/phototransistor pair is great for precisely identifying changes in reflectance (like line detection). It operates from 2.9 V to 5.5 V and offers dimmable brightness control independent of the supply voltage. In general, the closer the object, the higher the contrast between light and dark readings, but high-reflectance objects are generally detectable out to around 30 mm. This version features a high-performance, low-current QTRX sensor with lenses.

Pinout diagram of the QTRX/QTRXL-HD-01RC Reflectance Sensor Array.

QTRX-HD-01RC Reflectance Sensor, front and back views.

QTRX/QTRXL-HD-01RC Reflectance Sensor dimensions.

Dimensions: 5.0 × 20.0 × 4.4 mm (see the dimension diagram (1MB pdf) for more details)

Operating voltage: 2.9 V to 5.5 V

Sensor type: QTRX

Sensor count: 1

Full-brightness LED current: 3.5 mA (independent of supply voltage)

Max board current: 5 mA

Output format: digital I/O-compatible signal that can be read as a timed high pulse

Optimal sensing distance: 10 mm

Maximum recommended sensing distance: 30 mm

Weight: 0.25 g

These reflectance sensors feature a linear array of infrared emitter/phototransistor pair modules in a high-density (4 mm pitch) or medium-density (8 mm pitch) arrangement, which makes them well suited for applications that require detection of changes in reflectivity. This change in reflectivity can be due to a color change at a fixed distance, such as when sensing a black line on a white background, as well as due to a change in the distance to or presence of an object in front of the sensor. A variety of sensor counts and densities is available so you can pick the ideal arrangement for your application. Since the outputs are all independent, you can connect just some of the channels to attain an irregular or non-standard sensor spacing.

Unlike our original QTR sensor modules, these units have integrated LED drivers that provide brightness control independent of the supply voltage, which can be anywhere from 2.9 V to 5.5 V, while enabling optional dimming to any of 32 possible brightness settings. For high-density (HD) modules with five or more sensors and medium-density (MD) modules with eleven or more sensors, there are separate controls for the odd-numbered and even-numbered LEDs, which gives you extra options for detecting light reflected at various angles. See the “Emitter control” section below for more information on using this feature.

Two different sensor options are available, denoted by “QTR” or “QTRX” in the product name. The “QTR” versions feature lower-cost sensor modules without lenses while the “QTRX” versions feature higher-performance sensor modules with lenses, which allow similar performance at a much lower IR LED current. You can see the two different sensor styles in the pictures below of the 4-channel modules:

QTR-HD-04A Reflectance Sensor Array.

QTRX-HD-04RC Reflectance Sensor Array.

We also have several single-channel modules with the “QTRXL” designator that offer extra-long range by using the QTRX-style sensor module with higher current through the emitter.

Each sensor option is available in two output types: an “A” version with analog voltage outputs between 0 V and VCC, and an “RC” version with outputs that can be read with a digital I/O line on a microcontroller by first setting the lines high and then releasing them and timing how long it takes them to read as low (typically anywhere from a few microseconds to a few milliseconds). The lower the output voltage or shorter the voltage decay time, the higher the reflectance. The following simplified schematic diagrams show the circuits for the individual channels:

Schematic diagrams of individual QTR sensor channels for A version (left) and RC version (right). This applies only to the newer QTRs with dimmable emitters.

Our Arduino library makes it easy to use these sensor modules with an Arduino or compatible controller by providing methods for controlling the emitters, calibrating the module, and reading the individual sensor values from either the A or RC versions. It also has a method specifically for line-following applications to compute the location of the line under the array.

Note: Unlike most of our products, these sensor arrays do not ship with any headers or connectors included, so you will need to supply your own or solder wires directly to the board to use it. See our selection of male headers, female headers, and pre-crimped wires for various connector options.

Each sensor on the A versions outputs its reflectance measurement as an analog voltage that can range from 0 V when the reflectance is very strong to VCC when the reflectance is very weak. The typical sequence for reading a sensor is:

Use a microcontroller’s analog-to-digital converter (ADC) to measure the voltages.

Use a comparator with an adjustable threshold to convert each analog voltage into a digital (i.e. black/white) signal that can be read by the digital I/O line of a microcontroller.

Connect each output directly to a digital I/O line of a microcontroller and rely upon its logic threshold.

This last method will work if you are able to get high reflectance from your white surface as depicted in the left image, but will probably fail if you have a lower-reflectance signal profile like the one on the right.

QTR-1A output 1/8" away from a spinning white disk with a black line on it.

QTR-1A output 3/8" away from a spinning white disk with a black line on it.

Each sensor on the RC versions requires a digital I/O line capable of driving the output line high and then measuring the time for the output voltage to decay. The typical sequence for reading a sensor is:

QTR-1RC output (yellow) when 1/8" above a black line and microcontroller timing of that output (blue).

QTR-1RC output (yellow) when 1/8" above a white surface and microcontroller timing of that output (blue).

Turn on IR LEDs (optional).

Set the I/O line to an output and drive it high.

Allow at least 10 μs for the sensor output to rise.

Make the I/O line an input (high impedance).

Measure the time for the voltage to decay by waiting for the I/O line to go low.

Turn off IR LEDs (optional).

These steps can typically be executed in parallel on multiple I/O lines.

With a strong reflectance, the decay time can be as low as a few microseconds; with no reflectance, the decay time can be up to a few milliseconds. The exact time of the decay depends on your microcontroller’s I/O line characteristics. Meaningful results can be available within 1 ms in typical cases (i.e. when not trying to measure subtle differences in low-reflectance scenarios), allowing up to 1 kHz sampling of all sensors. If lower-frequency sampling is sufficient, you can achieve substantial power savings by turning off the LEDs. For example, if a 100 Hz sampling rate is acceptable, the LEDs can be off 90% of the time, lowering average current consumption from 125 mA to 13 mA.

These reflectance sensor arrays maintain a constant current through their IR emitters, keeping the emitters’ brightness constant, independent of the supply voltage (2.9 V to 5.5 V). The emitters can be controlled with the board’s CTRL pins, and the details of the control depends on the array size and density:

HD units with 5 or more sensors and MD units with 11 or more sensors have two emitter control pins: CTRL ODD and CTRL EVEN. By default, these are connected together with a 1 kΩ resistor and pulled up, turning on all the emitters by default and allowing them to be controlled with a signal on either pin, but the CTRL ODD and CTRL EVEN pins can be driven separately for independent control of the odd-numbered and even-numbered emitters.

MD units with 3-10 sensors also have two emitter control pins since these are made by only populating every other sensor on an HD board, but only the CTRL ODD pin will have an effect on these versions (it is not possible to independently control alternate emitters).

HD units with 4 or fewer sensors and MD units with 2 or fewer sensors have a single CTRL pin that controls all of the emitters.

Driving a CTRL pin low for at least 1 ms turns off the associated emitter LEDs, while driving it high (or allowing the board to pull it high) turns on the emitters with the board’s default (full) current, which is 30 mA for “QTR” versions and 3.5 mA for “QTRX” versions. For more advanced use, the CTRL pin can be pulsed low to cycle the associated emitters through 32 dimming levels.

Demo of IR LED dimming and independent even/odd control on the QTR-HD-07x (as seen through an old digital camera that can see IR).

Demo of IR LED dimming and independent even/odd control on the QTRX-HD-07x (as seen through an old digital camera that can see IR).

To send a pulse, you should drive the CTRL pin low for at least 0.5 μs (but no more than 300 μs), then high for at least 0.5 μs; (it should remain high after the last pulse). Each pulse causes the driver to advance to the next dimming level, wrapping around to 100% after the lowest-current level. Each dimming level corresponds to a 3.33% reduction in current, except for the last three levels, which represent a 1.67% reduction, as shown in the table below. Note that turning the LEDs off with a >1 ms pulse and then back on resets them to full current.

For example, to reduce the emitter current to 50%, you would apply 15 low pulses to the CTRL pin and then keep it high after the last pulse.

pitch × sensors

size(mm)

output

max current

optimalrange

LED

board

8 mm × 2

13.0 × 20.0

analog

3.5 mA

5 mA

10 mm

This array of IR LED/phototransistor pairs is great for precisely identifying changes in reflectance (like line detection). It operates from 2.9 V to 5.5 V and offers dimmable brightness control independent of the supply voltage. In general, the closer the object, the higher the contrast between light and dark readings, but high-reflectance objects are generally detectable out to around 30 mm. This version features high-performance, low-current QTRX sensors with lenses.

QTRX-MD-02A Reflectance Sensor Array dimensions.

Dimensions: 13.0 × 20.0 × 3.0 mm (see the dimension diagram (1MB pdf) for more details)

Operating voltage: 2.9 V to 5.5 V

Sensor type: QTRX

Sensor count: 2

Sensor pitch: 8 mm

Full-brightness LED current: 3.5 mA (independent of supply voltage)

Max board current: 5 mA

Output format: analog voltages (0 V to VCC)

Optimal sensing distance: 10 mm

Maximum recommended sensing distance: 30 mm

Weight: 0.7 g

These reflectance sensors feature a linear array of infrared emitter/phototransistor pair modules in a high-density (4 mm pitch) or medium-density (8 mm pitch) arrangement, which makes them well suited for applications that require detection of changes in reflectivity. This change in reflectivity can be due to a color change at a fixed distance, such as when sensing a black line on a white background, as well as due to a change in the distance to or presence of an object in front of the sensor. A variety of sensor counts and densities is available so you can pick the ideal arrangement for your application. Since the outputs are all independent, you can connect just some of the channels to attain an irregular or non-standard sensor spacing.

Unlike our original QTR sensor modules, these units have integrated LED drivers that provide brightness control independent of the supply voltage, which can be anywhere from 2.9 V to 5.5 V, while enabling optional dimming to any of 32 possible brightness settings. For high-density (HD) modules with five or more sensors and medium-density (MD) modules with eleven or more sensors, there are separate controls for the odd-numbered and even-numbered LEDs, which gives you extra options for detecting light reflected at various angles. See the “Emitter control” section below for more information on using this feature.

Two different sensor options are available, denoted by “QTR” or “QTRX” in the product name. The “QTR” versions feature lower-cost sensor modules without lenses while the “QTRX” versions feature higher-performance sensor modules with lenses, which allow similar performance at a much lower IR LED current. You can see the two different sensor styles in the pictures below of the 4-channel modules:

QTR-HD-04A Reflectance Sensor Array.

QTRX-HD-04RC Reflectance Sensor Array.

We also have several single-channel modules with the “QTRXL” designator that offer extra-long range by using the QTRX-style sensor module with higher current through the emitter.

Each sensor option is available in two output types: an “A” version with analog voltage outputs between 0 V and VCC, and an “RC” version with outputs that can be read with a digital I/O line on a microcontroller by first setting the lines high and then releasing them and timing how long it takes them to read as low (typically anywhere from a few microseconds to a few milliseconds). The lower the output voltage or shorter the voltage decay time, the higher the reflectance. The following simplified schematic diagrams show the circuits for the individual channels:

Schematic diagrams of individual QTR sensor channels for A version (left) and RC version (right). This applies only to the newer QTRs with dimmable emitters.

Our Arduino library makes it easy to use these sensor modules with an Arduino or compatible controller by providing methods for controlling the emitters, calibrating the module, and reading the individual sensor values from either the A or RC versions. It also has a method specifically for line-following applications to compute the location of the line under the array.

Note: Unlike most of our products, these sensor arrays do not ship with any headers or connectors included, so you will need to supply your own or solder wires directly to the board to use it. See our selection of male headers, female headers, and pre-crimped wires for various connector options.

Each sensor on the A versions outputs its reflectance measurement as an analog voltage that can range from 0 V when the reflectance is very strong to VCC when the reflectance is very weak. The typical sequence for reading a sensor is:

Use a microcontroller’s analog-to-digital converter (ADC) to measure the voltages.

Use a comparator with an adjustable threshold to convert each analog voltage into a digital (i.e. black/white) signal that can be read by the digital I/O line of a microcontroller.

Connect each output directly to a digital I/O line of a microcontroller and rely upon its logic threshold.

This last method will work if you are able to get high reflectance from your white surface as depicted in the left image, but will probably fail if you have a lower-reflectance signal profile like the one on the right.

QTR-1A output 1/8" away from a spinning white disk with a black line on it.

QTR-1A output 3/8" away from a spinning white disk with a black line on it.

Each sensor on the RC versions requires a digital I/O line capable of driving the output line high and then measuring the time for the output voltage to decay. The typical sequence for reading a sensor is:

QTR-1RC output (yellow) when 1/8" above a black line and microcontroller timing of that output (blue).

QTR-1RC output (yellow) when 1/8" above a white surface and microcontroller timing of that output (blue).

Turn on IR LEDs (optional).

Set the I/O line to an output and drive it high.

Allow at least 10 μs for the sensor output to rise.

Make the I/O line an input (high impedance).

Measure the time for the voltage to decay by waiting for the I/O line to go low.

Turn off IR LEDs (optional).

These steps can typically be executed in parallel on multiple I/O lines.

With a strong reflectance, the decay time can be as low as a few microseconds; with no reflectance, the decay time can be up to a few milliseconds. The exact time of the decay depends on your microcontroller’s I/O line characteristics. Meaningful results can be available within 1 ms in typical cases (i.e. when not trying to measure subtle differences in low-reflectance scenarios), allowing up to 1 kHz sampling of all sensors. If lower-frequency sampling is sufficient, you can achieve substantial power savings by turning off the LEDs. For example, if a 100 Hz sampling rate is acceptable, the LEDs can be off 90% of the time, lowering average current consumption from 125 mA to 13 mA.

These reflectance sensor arrays maintain a constant current through their IR emitters, keeping the emitters’ brightness constant, independent of the supply voltage (2.9 V to 5.5 V). The emitters can be controlled with the board’s CTRL pins, and the details of the control depends on the array size and density:

HD units with 5 or more sensors and MD units with 11 or more sensors have two emitter control pins: CTRL ODD and CTRL EVEN. By default, these are connected together with a 1 kΩ resistor and pulled up, turning on all the emitters by default and allowing them to be controlled with a signal on either pin, but the CTRL ODD and CTRL EVEN pins can be driven separately for independent control of the odd-numbered and even-numbered emitters.

MD units with 3-10 sensors also have two emitter control pins since these are made by only populating every other sensor on an HD board, but only the CTRL ODD pin will have an effect on these versions (it is not possible to independently control alternate emitters).

HD units with 4 or fewer sensors and MD units with 2 or fewer sensors have a single CTRL pin that controls all of the emitters.

Driving a CTRL pin low for at least 1 ms turns off the associated emitter LEDs, while driving it high (or allowing the board to pull it high) turns on the emitters with the board’s default (full) current, which is 30 mA for “QTR” versions and 3.5 mA for “QTRX” versions. For more advanced use, the CTRL pin can be pulsed low to cycle the associated emitters through 32 dimming levels.

Demo of IR LED dimming and independent even/odd control on the QTR-HD-07x (as seen through an old digital camera that can see IR).

Demo of IR LED dimming and independent even/odd control on the QTRX-HD-07x (as seen through an old digital camera that can see IR).

To send a pulse, you should drive the CTRL pin low for at least 0.5 μs (but no more than 300 μs), then high for at least 0.5 μs; (it should remain high after the last pulse). Each pulse causes the driver to advance to the next dimming level, wrapping around to 100% after the lowest-current level. Each dimming level corresponds to a 3.33% reduction in current, except for the last three levels, which represent a 1.67% reduction, as shown in the table below. Note that turning the LEDs off with a >1 ms pulse and then back on resets them to full current.

For example, to reduce the emitter current to 50%, you would apply 15 low pulses to the CTRL pin and then keep it high after the last pulse.

pitch × sensors

size(mm)

output

max current

optimalrange

LED

board

8 mm × 2

13.0 × 20.0

RC (digital)

3.5 mA

5 mA

10 mm

This array of IR LED/phototransistor pairs is great for precisely identifying changes in reflectance (like line detection). It operates from 2.9 V to 5.5 V and offers dimmable brightness control independent of the supply voltage. In general, the closer the object, the higher the contrast between light and dark readings, but high-reflectance objects are generally detectable out to around 30 mm. This version features high-performance, low-current QTRX sensors with lenses.

QTRX-MD-02RC Reflectance Sensor Array dimensions.

Dimensions: 13.0 × 20.0 × 3.0 mm (see the dimension diagram (1MB pdf) for more details)

Operating voltage: 2.9 V to 5.5 V

Sensor type: QTRX

Sensor count: 2

Sensor pitch: 8 mm

Full-brightness LED current: 3.5 mA (independent of supply voltage)

Max board current: 5 mA

Output format: digital I/O-compatible signals that can be read in parallel as timed high pulses

Optimal sensing distance: 10 mm

Maximum recommended sensing distance: 30 mm

Weight: 0.7 g

These reflectance sensors feature a linear array of infrared emitter/phototransistor pair modules in a high-density (4 mm pitch) or medium-density (8 mm pitch) arrangement, which makes them well suited for applications that require detection of changes in reflectivity. This change in reflectivity can be due to a color change at a fixed distance, such as when sensing a black line on a white background, as well as due to a change in the distance to or presence of an object in front of the sensor. A variety of sensor counts and densities is available so you can pick the ideal arrangement for your application. Since the outputs are all independent, you can connect just some of the channels to attain an irregular or non-standard sensor spacing.

Unlike our original QTR sensor modules, these units have integrated LED drivers that provide brightness control independent of the supply voltage, which can be anywhere from 2.9 V to 5.5 V, while enabling optional dimming to any of 32 possible brightness settings. For high-density (HD) modules with five or more sensors and medium-density (MD) modules with eleven or more sensors, there are separate controls for the odd-numbered and even-numbered LEDs, which gives you extra options for detecting light reflected at various angles. See the “Emitter control” section below for more information on using this feature.

Two different sensor options are available, denoted by “QTR” or “QTRX” in the product name. The “QTR” versions feature lower-cost sensor modules without lenses while the “QTRX” versions feature higher-performance sensor modules with lenses, which allow similar performance at a much lower IR LED current. You can see the two different sensor styles in the pictures below of the 4-channel modules:

QTR-HD-04A Reflectance Sensor Array.

QTRX-HD-04RC Reflectance Sensor Array.

We also have several single-channel modules with the “QTRXL” designator that offer extra-long range by using the QTRX-style sensor module with higher current through the emitter.

Each sensor option is available in two output types: an “A” version with analog voltage outputs between 0 V and VCC, and an “RC” version with outputs that can be read with a digital I/O line on a microcontroller by first setting the lines high and then releasing them and timing how long it takes them to read as low (typically anywhere from a few microseconds to a few milliseconds). The lower the output voltage or shorter the voltage decay time, the higher the reflectance. The following simplified schematic diagrams show the circuits for the individual channels:

Schematic diagrams of individual QTR sensor channels for A version (left) and RC version (right). This applies only to the newer QTRs with dimmable emitters.

Our Arduino library makes it easy to use these sensor modules with an Arduino or compatible controller by providing methods for controlling the emitters, calibrating the module, and reading the individual sensor values from either the A or RC versions. It also has a method specifically for line-following applications to compute the location of the line under the array.

Note: Unlike most of our products, these sensor arrays do not ship with any headers or connectors included, so you will need to supply your own or solder wires directly to the board to use it. See our selection of male headers, female headers, and pre-crimped wires for various connector options.

Each sensor on the A versions outputs its reflectance measurement as an analog voltage that can range from 0 V when the reflectance is very strong to VCC when the reflectance is very weak. The typical sequence for reading a sensor is:

Use a microcontroller’s analog-to-digital converter (ADC) to measure the voltages.

Use a comparator with an adjustable threshold to convert each analog voltage into a digital (i.e. black/white) signal that can be read by the digital I/O line of a microcontroller.

Connect each output directly to a digital I/O line of a microcontroller and rely upon its logic threshold.

This last method will work if you are able to get high reflectance from your white surface as depicted in the left image, but will probably fail if you have a lower-reflectance signal profile like the one on the right.

QTR-1A output 1/8" away from a spinning white disk with a black line on it.

QTR-1A output 3/8" away from a spinning white disk with a black line on it.

Each sensor on the RC versions requires a digital I/O line capable of driving the output line high and then measuring the time for the output voltage to decay. The typical sequence for reading a sensor is:

QTR-1RC output (yellow) when 1/8" above a black line and microcontroller timing of that output (blue).

QTR-1RC output (yellow) when 1/8" above a white surface and microcontroller timing of that output (blue).

Turn on IR LEDs (optional).

Set the I/O line to an output and drive it high.

Allow at least 10 μs for the sensor output to rise.

Make the I/O line an input (high impedance).

Measure the time for the voltage to decay by waiting for the I/O line to go low.

Turn off IR LEDs (optional).

These steps can typically be executed in parallel on multiple I/O lines.

With a strong reflectance, the decay time can be as low as a few microseconds; with no reflectance, the decay time can be up to a few milliseconds. The exact time of the decay depends on your microcontroller’s I/O line characteristics. Meaningful results can be available within 1 ms in typical cases (i.e. when not trying to measure subtle differences in low-reflectance scenarios), allowing up to 1 kHz sampling of all sensors. If lower-frequency sampling is sufficient, you can achieve substantial power savings by turning off the LEDs. For example, if a 100 Hz sampling rate is acceptable, the LEDs can be off 90% of the time, lowering average current consumption from 125 mA to 13 mA.

These reflectance sensor arrays maintain a constant current through their IR emitters, keeping the emitters’ brightness constant, independent of the supply voltage (2.9 V to 5.5 V). The emitters can be controlled with the board’s CTRL pins, and the details of the control depends on the array size and density:

HD units with 5 or more sensors and MD units with 11 or more sensors have two emitter control pins: CTRL ODD and CTRL EVEN. By default, these are connected together with a 1 kΩ resistor and pulled up, turning on all the emitters by default and allowing them to be controlled with a signal on either pin, but the CTRL ODD and CTRL EVEN pins can be driven separately for independent control of the odd-numbered and even-numbered emitters.

MD units with 3-10 sensors also have two emitter control pins since these are made by only populating every other sensor on an HD board, but only the CTRL ODD pin will have an effect on these versions (it is not possible to independently control alternate emitters).

HD units with 4 or fewer sensors and MD units with 2 or fewer sensors have a single CTRL pin that controls all of the emitters.

Driving a CTRL pin low for at least 1 ms turns off the associated emitter LEDs, while driving it high (or allowing the board to pull it high) turns on the emitters with the board’s default (full) current, which is 30 mA for “QTR” versions and 3.5 mA for “QTRX” versions. For more advanced use, the CTRL pin can be pulsed low to cycle the associated emitters through 32 dimming levels.

Demo of IR LED dimming and independent even/odd control on the QTR-HD-07x (as seen through an old digital camera that can see IR).

Demo of IR LED dimming and independent even/odd control on the QTRX-HD-07x (as seen through an old digital camera that can see IR).

To send a pulse, you should drive the CTRL pin low for at least 0.5 μs (but no more than 300 μs), then high for at least 0.5 μs; (it should remain high after the last pulse). Each pulse causes the driver to advance to the next dimming level, wrapping around to 100% after the lowest-current level. Each dimming level corresponds to a 3.33% reduction in current, except for the last three levels, which represent a 1.67% reduction, as shown in the table below. Note that turning the LEDs off with a >1 ms pulse and then back on resets them to full current.

For example, to reduce the emitter current to 50%, you would apply 15 low pulses to the CTRL pin and then keep it high after the last pulse.

pitch × sensors

size(mm)

output

max current

optimalrange

LED

board

4 mm × 3

13.0 × 20.0

analog

3.5 mA

9 mA

10 mm

This array of IR LED/phototransistor pairs is great for precisely identifying changes in reflectance (like line detection). It operates from 2.9 V to 5.5 V and offers dimmable brightness control independent of the supply voltage. In general, the closer the object, the higher the contrast between light and dark readings, but high-reflectance objects are generally detectable out to around 30 mm. This version features high-performance, low-current QTRX sensors with lenses.

QTRX-HD-03A Reflectance Sensor Array dimensions.

Dimensions: 13.0 × 20.0 × 3.0 mm (see the dimension diagram (1MB pdf) for more details)

Operating voltage: 2.9 V to 5.5 V

Sensor type: QTRX

Sensor count: 3

Sensor pitch: 4 mm

Full-brightness LED current: 3.5 mA (independent of supply voltage)

Max board current: 9 mA

Output format: analog voltages (0 V to VCC)

Optimal sensing distance: 10 mm

Maximum recommended sensing distance: 30 mm

Weight: 0.8 g

These reflectance sensors feature a linear array of infrared emitter/phototransistor pair modules in a high-density (4 mm pitch) or medium-density (8 mm pitch) arrangement, which makes them well suited for applications that require detection of changes in reflectivity. This change in reflectivity can be due to a color change at a fixed distance, such as when sensing a black line on a white background, as well as due to a change in the distance to or presence of an object in front of the sensor. A variety of sensor counts and densities is available so you can pick the ideal arrangement for your application. Since the outputs are all independent, you can connect just some of the channels to attain an irregular or non-standard sensor spacing.

Unlike our original QTR sensor modules, these units have integrated LED drivers that provide brightness control independent of the supply voltage, which can be anywhere from 2.9 V to 5.5 V, while enabling optional dimming to any of 32 possible brightness settings. For high-density (HD) modules with five or more sensors and medium-density (MD) modules with eleven or more sensors, there are separate controls for the odd-numbered and even-numbered LEDs, which gives you extra options for detecting light reflected at various angles. See the “Emitter control” section below for more information on using this feature.

Two different sensor options are available, denoted by “QTR” or “QTRX” in the product name. The “QTR” versions feature lower-cost sensor modules without lenses while the “QTRX” versions feature higher-performance sensor modules with lenses, which allow similar performance at a much lower IR LED current. You can see the two different sensor styles in the pictures below of the 4-channel modules:

QTR-HD-04A Reflectance Sensor Array.

QTRX-HD-04RC Reflectance Sensor Array.

We also have several single-channel modules with the “QTRXL” designator that offer extra-long range by using the QTRX-style sensor module with higher current through the emitter.

Each sensor option is available in two output types: an “A” version with analog voltage outputs between 0 V and VCC, and an “RC” version with outputs that can be read with a digital I/O line on a microcontroller by first setting the lines high and then releasing them and timing how long it takes them to read as low (typically anywhere from a few microseconds to a few milliseconds). The lower the output voltage or shorter the voltage decay time, the higher the reflectance. The following simplified schematic diagrams show the circuits for the individual channels:

Schematic diagrams of individual QTR sensor channels for A version (left) and RC version (right). This applies only to the newer QTRs with dimmable emitters.

Our Arduino library makes it easy to use these sensor modules with an Arduino or compatible controller by providing methods for controlling the emitters, calibrating the module, and reading the individual sensor values from either the A or RC versions. It also has a method specifically for line-following applications to compute the location of the line under the array.

Note: Unlike most of our products, these sensor arrays do not ship with any headers or connectors included, so you will need to supply your own or solder wires directly to the board to use it. See our selection of male headers, female headers, and pre-crimped wires for various connector options.

Each sensor on the A versions outputs its reflectance measurement as an analog voltage that can range from 0 V when the reflectance is very strong to VCC when the reflectance is very weak. The typical sequence for reading a sensor is:

Use a microcontroller’s analog-to-digital converter (ADC) to measure the voltages.

Use a comparator with an adjustable threshold to convert each analog voltage into a digital (i.e. black/white) signal that can be read by the digital I/O line of a microcontroller.

Connect each output directly to a digital I/O line of a microcontroller and rely upon its logic threshold.

This last method will work if you are able to get high reflectance from your white surface as depicted in the left image, but will probably fail if you have a lower-reflectance signal profile like the one on the right.

QTR-1A output 1/8" away from a spinning white disk with a black line on it.

QTR-1A output 3/8" away from a spinning white disk with a black line on it.

Each sensor on the RC versions requires a digital I/O line capable of driving the output line high and then measuring the time for the output voltage to decay. The typical sequence for reading a sensor is:

QTR-1RC output (yellow) when 1/8" above a black line and microcontroller timing of that output (blue).

QTR-1RC output (yellow) when 1/8" above a white surface and microcontroller timing of that output (blue).

Turn on IR LEDs (optional).

Set the I/O line to an output and drive it high.

Allow at least 10 μs for the sensor output to rise.

Make the I/O line an input (high impedance).

Measure the time for the voltage to decay by waiting for the I/O line to go low.

Turn off IR LEDs (optional).

These steps can typically be executed in parallel on multiple I/O lines.

With a strong reflectance, the decay time can be as low as a few microseconds; with no reflectance, the decay time can be up to a few milliseconds. The exact time of the decay depends on your microcontroller’s I/O line characteristics. Meaningful results can be available within 1 ms in typical cases (i.e. when not trying to measure subtle differences in low-reflectance scenarios), allowing up to 1 kHz sampling of all sensors. If lower-frequency sampling is sufficient, you can achieve substantial power savings by turning off the LEDs. For example, if a 100 Hz sampling rate is acceptable, the LEDs can be off 90% of the time, lowering average current consumption from 125 mA to 13 mA.

These reflectance sensor arrays maintain a constant current through their IR emitters, keeping the emitters’ brightness constant, independent of the supply voltage (2.9 V to 5.5 V). The emitters can be controlled with the board’s CTRL pins, and the details of the control depends on the array size and density:

HD units with 5 or more sensors and MD units with 11 or more sensors have two emitter control pins: CTRL ODD and CTRL EVEN. By default, these are connected together with a 1 kΩ resistor and pulled up, turning on all the emitters by default and allowing them to be controlled with a signal on either pin, but the CTRL ODD and CTRL EVEN pins can be driven separately for independent control of the odd-numbered and even-numbered emitters.

MD units with 3-10 sensors also have two emitter control pins since these are made by only populating every other sensor on an HD board, but only the CTRL ODD pin will have an effect on these versions (it is not possible to independently control alternate emitters).

HD units with 4 or fewer sensors and MD units with 2 or fewer sensors have a single CTRL pin that controls all of the emitters.

Driving a CTRL pin low for at least 1 ms turns off the associated emitter LEDs, while driving it high (or allowing the board to pull it high) turns on the emitters with the board’s default (full) current, which is 30 mA for “QTR” versions and 3.5 mA for “QTRX” versions. For more advanced use, the CTRL pin can be pulsed low to cycle the associated emitters through 32 dimming levels.

Demo of IR LED dimming and independent even/odd control on the QTR-HD-07x (as seen through an old digital camera that can see IR).

Demo of IR LED dimming and independent even/odd control on the QTRX-HD-07x (as seen through an old digital camera that can see IR).

To send a pulse, you should drive the CTRL pin low for at least 0.5 μs (but no more than 300 μs), then high for at least 0.5 μs; (it should remain high after the last pulse). Each pulse causes the driver to advance to the next dimming level, wrapping around to 100% after the lowest-current level. Each dimming level corresponds to a 3.33% reduction in current, except for the last three levels, which represent a 1.67% reduction, as shown in the table below. Note that turning the LEDs off with a >1 ms pulse and then back on resets them to full current.

For example, to reduce the emitter current to 50%, you would apply 15 low pulses to the CTRL pin and then keep it high after the last pulse.

pitch × sensors

size(mm)

output

max current

optimalrange

LED

board

4 mm × 3

13.0 × 20.0

RC (digital)

3.5 mA

9 mA

10 mm

This array of IR LED/phototransistor pairs is great for precisely identifying changes in reflectance (like line detection). It operates from 2.9 V to 5.5 V and offers dimmable brightness control independent of the supply voltage. In general, the closer the object, the higher the contrast between light and dark readings, but high-reflectance objects are generally detectable out to around 30 mm. This version features high-performance, low-current QTRX sensors with lenses.

QTRX-HD-03RC Reflectance Sensor Array dimensions.

Dimensions: 13.0 × 20.0 × 3.0 mm (see the dimension diagram (1MB pdf) for more details)

Operating voltage: 2.9 V to 5.5 V

Sensor type: QTRX

Sensor count: 3

Sensor pitch: 4 mm

Full-brightness LED current: 3.5 mA (independent of supply voltage)

Max board current: 9 mA

Output format: digital I/O-compatible signals that can be read in parallel as timed high pulses

Optimal sensing distance: 10 mm

Maximum recommended sensing distance: 30 mm

Weight: 0.8 g

These reflectance sensors feature a linear array of infrared emitter/phototransistor pair modules in a high-density (4 mm pitch) or medium-density (8 mm pitch) arrangement, which makes them well suited for applications that require detection of changes in reflectivity. This change in reflectivity can be due to a color change at a fixed distance, such as when sensing a black line on a white background, as well as due to a change in the distance to or presence of an object in front of the sensor. A variety of sensor counts and densities is available so you can pick the ideal arrangement for your application. Since the outputs are all independent, you can connect just some of the channels to attain an irregular or non-standard sensor spacing.

Unlike our original QTR sensor modules, these units have integrated LED drivers that provide brightness control independent of the supply voltage, which can be anywhere from 2.9 V to 5.5 V, while enabling optional dimming to any of 32 possible brightness settings. For high-density (HD) modules with five or more sensors and medium-density (MD) modules with eleven or more sensors, there are separate controls for the odd-numbered and even-numbered LEDs, which gives you extra options for detecting light reflected at various angles. See the “Emitter control” section below for more information on using this feature.

Two different sensor options are available, denoted by “QTR” or “QTRX” in the product name. The “QTR” versions feature lower-cost sensor modules without lenses while the “QTRX” versions feature higher-performance sensor modules with lenses, which allow similar performance at a much lower IR LED current. You can see the two different sensor styles in the pictures below of the 4-channel modules:

QTR-HD-04A Reflectance Sensor Array.

QTRX-HD-04RC Reflectance Sensor Array.

We also have several single-channel modules with the “QTRXL” designator that offer extra-long range by using the QTRX-style sensor module with higher current through the emitter.

Each sensor option is available in two output types: an “A” version with analog voltage outputs between 0 V and VCC, and an “RC” version with outputs that can be read with a digital I/O line on a microcontroller by first setting the lines high and then releasing them and timing how long it takes them to read as low (typically anywhere from a few microseconds to a few milliseconds). The lower the output voltage or shorter the voltage decay time, the higher the reflectance. The following simplified schematic diagrams show the circuits for the individual channels:

Schematic diagrams of individual QTR sensor channels for A version (left) and RC version (right). This applies only to the newer QTRs with dimmable emitters.

Our Arduino library makes it easy to use these sensor modules with an Arduino or compatible controller by providing methods for controlling the emitters, calibrating the module, and reading the individual sensor values from either the A or RC versions. It also has a method specifically for line-following applications to compute the location of the line under the array.

Note: Unlike most of our products, these sensor arrays do not ship with any headers or connectors included, so you will need to supply your own or solder wires directly to the board to use it. See our selection of male headers, female headers, and pre-crimped wires for various connector options.

Each sensor on the A versions outputs its reflectance measurement as an analog voltage that can range from 0 V when the reflectance is very strong to VCC when the reflectance is very weak. The typical sequence for reading a sensor is:

Use a microcontroller’s analog-to-digital converter (ADC) to measure the voltages.

Use a comparator with an adjustable threshold to convert each analog voltage into a digital (i.e. black/white) signal that can be read by the digital I/O line of a microcontroller.

Connect each output directly to a digital I/O line of a microcontroller and rely upon its logic threshold.

This last method will work if you are able to get high reflectance from your white surface as depicted in the left image, but will probably fail if you have a lower-reflectance signal profile like the one on the right.

QTR-1A output 1/8" away from a spinning white disk with a black line on it.

QTR-1A output 3/8" away from a spinning white disk with a black line on it.

Each sensor on the RC versions requires a digital I/O line capable of driving the output line high and then measuring the time for the output voltage to decay. The typical sequence for reading a sensor is:

QTR-1RC output (yellow) when 1/8" above a black line and microcontroller timing of that output (blue).

QTR-1RC output (yellow) when 1/8" above a white surface and microcontroller timing of that output (blue).

Turn on IR LEDs (optional).

Set the I/O line to an output and drive it high.

Allow at least 10 μs for the sensor output to rise.

Make the I/O line an input (high impedance).

Measure the time for the voltage to decay by waiting for the I/O line to go low.

Turn off IR LEDs (optional).

These steps can typically be executed in parallel on multiple I/O lines.

With a strong reflectance, the decay time can be as low as a few microseconds; with no reflectance, the decay time can be up to a few milliseconds. The exact time of the decay depends on your microcontroller’s I/O line characteristics. Meaningful results can be available within 1 ms in typical cases (i.e. when not trying to measure subtle differences in low-reflectance scenarios), allowing up to 1 kHz sampling of all sensors. If lower-frequency sampling is sufficient, you can achieve substantial power savings by turning off the LEDs. For example, if a 100 Hz sampling rate is acceptable, the LEDs can be off 90% of the time, lowering average current consumption from 125 mA to 13 mA.

These reflectance sensor arrays maintain a constant current through their IR emitters, keeping the emitters’ brightness constant, independent of the supply voltage (2.9 V to 5.5 V). The emitters can be controlled with the board’s CTRL pins, and the details of the control depends on the array size and density:

HD units with 5 or more sensors and MD units with 11 or more sensors have two emitter control pins: CTRL ODD and CTRL EVEN. By default, these are connected together with a 1 kΩ resistor and pulled up, turning on all the emitters by default and allowing them to be controlled with a signal on either pin, but the CTRL ODD and CTRL EVEN pins can be driven separately for independent control of the odd-numbered and even-numbered emitters.

MD units with 3-10 sensors also have two emitter control pins since these are made by only populating every other sensor on an HD board, but only the CTRL ODD pin will have an effect on these versions (it is not possible to independently control alternate emitters).

HD units with 4 or fewer sensors and MD units with 2 or fewer sensors have a single CTRL pin that controls all of the emitters.

Driving a CTRL pin low for at least 1 ms turns off the associated emitter LEDs, while driving it high (or allowing the board to pull it high) turns on the emitters with the board’s default (full) current, which is 30 mA for “QTR” versions and 3.5 mA for “QTRX” versions. For more advanced use, the CTRL pin can be pulsed low to cycle the associated emitters through 32 dimming levels.

Demo of IR LED dimming and independent even/odd control on the QTR-HD-07x (as seen through an old digital camera that can see IR).

Demo of IR LED dimming and independent even/odd control on the QTRX-HD-07x (as seen through an old digital camera that can see IR).

To send a pulse, you should drive the CTRL pin low for at least 0.5 μs (but no more than 300 μs), then high for at least 0.5 μs; (it should remain high after the last pulse). Each pulse causes the driver to advance to the next dimming level, wrapping around to 100% after the lowest-current level. Each dimming level corresponds to a 3.33% reduction in current, except for the last three levels, which represent a 1.67% reduction, as shown in the table below. Note that turning the LEDs off with a >1 ms pulse and then back on resets them to full current.

For example, to reduce the emitter current to 50%, you would apply 15 low pulses to the CTRL pin and then keep it high after the last pulse.

pitch × sensors

size(mm)

output

max current

optimalrange

LED

board

4 mm × 3

13.0 × 20.0

analog

30 mA

62 mA

5 mm

This array of IR LED/phototransistor pairs is great for precisely identifying changes in reflectance (like line detection). It operates from 2.9 V to 5.5 V and offers dimmable brightness control independent of the supply voltage. In general, the closer the object, the higher the contrast between light and dark readings, but high-reflectance objects are generally detectable out to around 30 mm. This version features the traditional-style QTR sensors without lenses.

QTR-HD-03A Reflectance Sensor Array dimensions.

Dimensions: 13.0 × 20.0 × 2.5 mm (see the dimension diagram (1MB pdf) for more details)

Operating voltage: 2.9 V to 5.5 V

Sensor type: QTR

Sensor count: 3

Sensor pitch: 4 mm

Full-brightness LED current: 30 mA (independent of supply voltage)

Max board current: 62 mA

Output format: analog voltages (0 V to VCC)

Optimal sensing distance: 5 mm

Maximum recommended sensing distance: 30 mm

Weight: 0.8 g

These reflectance sensors feature a linear array of infrared emitter/phototransistor pair modules in a high-density (4 mm pitch) or medium-density (8 mm pitch) arrangement, which makes them well suited for applications that require detection of changes in reflectivity. This change in reflectivity can be due to a color change at a fixed distance, such as when sensing a black line on a white background, as well as due to a change in the distance to or presence of an object in front of the sensor. A variety of sensor counts and densities is available so you can pick the ideal arrangement for your application. Since the outputs are all independent, you can connect just some of the channels to attain an irregular or non-standard sensor spacing.

Unlike our original QTR sensor modules, these units have integrated LED drivers that provide brightness control independent of the supply voltage, which can be anywhere from 2.9 V to 5.5 V, while enabling optional dimming to any of 32 possible brightness settings. For high-density (HD) modules with five or more sensors and medium-density (MD) modules with eleven or more sensors, there are separate controls for the odd-numbered and even-numbered LEDs, which gives you extra options for detecting light reflected at various angles. See the “Emitter control” section below for more information on using this feature.

Two different sensor options are available, denoted by “QTR” or “QTRX” in the product name. The “QTR” versions feature lower-cost sensor modules without lenses while the “QTRX” versions feature higher-performance sensor modules with lenses, which allow similar performance at a much lower IR LED current. You can see the two different sensor styles in the pictures below of the 4-channel modules:

QTR-HD-04A Reflectance Sensor Array.

QTRX-HD-04RC Reflectance Sensor Array.

We also have several single-channel modules with the “QTRXL” designator that offer extra-long range by using the QTRX-style sensor module with higher current through the emitter.

Each sensor option is available in two output types: an “A” version with analog voltage outputs between 0 V and VCC, and an “RC” version with outputs that can be read with a digital I/O line on a microcontroller by first setting the lines high and then releasing them and timing how long it takes them to read as low (typically anywhere from a few microseconds to a few milliseconds). The lower the output voltage or shorter the voltage decay time, the higher the reflectance. The following simplified schematic diagrams show the circuits for the individual channels:

Schematic diagrams of individual QTR sensor channels for A version (left) and RC version (right). This applies only to the newer QTRs with dimmable emitters.

Our Arduino library makes it easy to use these sensor modules with an Arduino or compatible controller by providing methods for controlling the emitters, calibrating the module, and reading the individual sensor values from either the A or RC versions. It also has a method specifically for line-following applications to compute the location of the line under the array.

Note: Unlike most of our products, these sensor arrays do not ship with any headers or connectors included, so you will need to supply your own or solder wires directly to the board to use it. See our selection of male headers, female headers, and pre-crimped wires for various connector options.

Each sensor on the A versions outputs its reflectance measurement as an analog voltage that can range from 0 V when the reflectance is very strong to VCC when the reflectance is very weak. The typical sequence for reading a sensor is:

Use a microcontroller’s analog-to-digital converter (ADC) to measure the voltages.

Use a comparator with an adjustable threshold to convert each analog voltage into a digital (i.e. black/white) signal that can be read by the digital I/O line of a microcontroller.

Connect each output directly to a digital I/O line of a microcontroller and rely upon its logic threshold.

This last method will work if you are able to get high reflectance from your white surface as depicted in the left image, but will probably fail if you have a lower-reflectance signal profile like the one on the right.

QTR-1A output 1/8" away from a spinning white disk with a black line on it.

QTR-1A output 3/8" away from a spinning white disk with a black line on it.

Each sensor on the RC versions requires a digital I/O line capable of driving the output line high and then measuring the time for the output voltage to decay. The typical sequence for reading a sensor is:

QTR-1RC output (yellow) when 1/8" above a black line and microcontroller timing of that output (blue).

QTR-1RC output (yellow) when 1/8" above a white surface and microcontroller timing of that output (blue).

Turn on IR LEDs (optional).

Set the I/O line to an output and drive it high.

Allow at least 10 μs for the sensor output to rise.

Make the I/O line an input (high impedance).

Measure the time for the voltage to decay by waiting for the I/O line to go low.

Turn off IR LEDs (optional).

These steps can typically be executed in parallel on multiple I/O lines.

With a strong reflectance, the decay time can be as low as a few microseconds; with no reflectance, the decay time can be up to a few milliseconds. The exact time of the decay depends on your microcontroller’s I/O line characteristics. Meaningful results can be available within 1 ms in typical cases (i.e. when not trying to measure subtle differences in low-reflectance scenarios), allowing up to 1 kHz sampling of all sensors. If lower-frequency sampling is sufficient, you can achieve substantial power savings by turning off the LEDs. For example, if a 100 Hz sampling rate is acceptable, the LEDs can be off 90% of the time, lowering average current consumption from 125 mA to 13 mA.

These reflectance sensor arrays maintain a constant current through their IR emitters, keeping the emitters’ brightness constant, independent of the supply voltage (2.9 V to 5.5 V). The emitters can be controlled with the board’s CTRL pins, and the details of the control depends on the array size and density:

HD units with 5 or more sensors and MD units with 11 or more sensors have two emitter control pins: CTRL ODD and CTRL EVEN. By default, these are connected together with a 1 kΩ resistor and pulled up, turning on all the emitters by default and allowing them to be controlled with a signal on either pin, but the CTRL ODD and CTRL EVEN pins can be driven separately for independent control of the odd-numbered and even-numbered emitters.

MD units with 3-10 sensors also have two emitter control pins since these are made by only populating every other sensor on an HD board, but only the CTRL ODD pin will have an effect on these versions (it is not possible to independently control alternate emitters).

HD units with 4 or fewer sensors and MD units with 2 or fewer sensors have a single CTRL pin that controls all of the emitters.

Driving a CTRL pin low for at least 1 ms turns off the associated emitter LEDs, while driving it high (or allowing the board to pull it high) turns on the emitters with the board’s default (full) current, which is 30 mA for “QTR” versions and 3.5 mA for “QTRX” versions. For more advanced use, the CTRL pin can be pulsed low to cycle the associated emitters through 32 dimming levels.

Demo of IR LED dimming and independent even/odd control on the QTR-HD-07x (as seen through an old digital camera that can see IR).

Demo of IR LED dimming and independent even/odd control on the QTRX-HD-07x (as seen through an old digital camera that can see IR).

To send a pulse, you should drive the CTRL pin low for at least 0.5 μs (but no more than 300 μs), then high for at least 0.5 μs; (it should remain high after the last pulse). Each pulse causes the driver to advance to the next dimming level, wrapping around to 100% after the lowest-current level. Each dimming level corresponds to a 3.33% reduction in current, except for the last three levels, which represent a 1.67% reduction, as shown in the table below. Note that turning the LEDs off with a >1 ms pulse and then back on resets them to full current.

For example, to reduce the emitter current to 50%, you would apply 15 low pulses to the CTRL pin and then keep it high after the last pulse.

pitch × sensors

size(mm)

output

max current

optimalrange

LED

board

4 mm × 3

13.0 × 20.0

RC (digital)

30 mA

62 mA

5 mm

This array of IR LED/phototransistor pairs is great for precisely identifying changes in reflectance (like line detection). It operates from 2.9 V to 5.5 V and offers dimmable brightness control independent of the supply voltage. In general, the closer the object, the higher the contrast between light and dark readings, but high-reflectance objects are generally detectable out to around 30 mm. This version features the traditional-style QTR sensors without lenses.

QTR-HD-03RC Reflectance Sensor Array dimensions.

Dimensions: 13.0 × 20.0 × 2.5 mm (see the dimension diagram (1MB pdf) for more details)

Operating voltage: 2.9 V to 5.5 V

Sensor type: QTR

Sensor count: 3

Sensor pitch: 4 mm

Full-brightness LED current: 30 mA (independent of supply voltage)

Max board current: 62 mA

Output format: digital I/O-compatible signals that can be read in parallel as timed high pulses

Optimal sensing distance: 5 mm

Maximum recommended sensing distance: 30 mm

Weight: 0.8 g

These reflectance sensors feature a linear array of infrared emitter/phototransistor pair modules in a high-density (4 mm pitch) or medium-density (8 mm pitch) arrangement, which makes them well suited for applications that require detection of changes in reflectivity. This change in reflectivity can be due to a color change at a fixed distance, such as when sensing a black line on a white background, as well as due to a change in the distance to or presence of an object in front of the sensor. A variety of sensor counts and densities is available so you can pick the ideal arrangement for your application. Since the outputs are all independent, you can connect just some of the channels to attain an irregular or non-standard sensor spacing.

Unlike our original QTR sensor modules, these units have integrated LED drivers that provide brightness control independent of the supply voltage, which can be anywhere from 2.9 V to 5.5 V, while enabling optional dimming to any of 32 possible brightness settings. For high-density (HD) modules with five or more sensors and medium-density (MD) modules with eleven or more sensors, there are separate controls for the odd-numbered and even-numbered LEDs, which gives you extra options for detecting light reflected at various angles. See the “Emitter control” section below for more information on using this feature.

Two different sensor options are available, denoted by “QTR” or “QTRX” in the product name. The “QTR” versions feature lower-cost sensor modules without lenses while the “QTRX” versions feature higher-performance sensor modules with lenses, which allow similar performance at a much lower IR LED current. You can see the two different sensor styles in the pictures below of the 4-channel modules:

QTR-HD-04A Reflectance Sensor Array.

QTRX-HD-04RC Reflectance Sensor Array.

We also have several single-channel modules with the “QTRXL” designator that offer extra-long range by using the QTRX-style sensor module with higher current through the emitter.

Each sensor option is available in two output types: an “A” version with analog voltage outputs between 0 V and VCC, and an “RC” version with outputs that can be read with a digital I/O line on a microcontroller by first setting the lines high and then releasing them and timing how long it takes them to read as low (typically anywhere from a few microseconds to a few milliseconds). The lower the output voltage or shorter the voltage decay time, the higher the reflectance. The following simplified schematic diagrams show the circuits for the individual channels:

Schematic diagrams of individual QTR sensor channels for A version (left) and RC version (right). This applies only to the newer QTRs with dimmable emitters.

Our Arduino library makes it easy to use these sensor modules with an Arduino or compatible controller by providing methods for controlling the emitters, calibrating the module, and reading the individual sensor values from either the A or RC versions. It also has a method specifically for line-following applications to compute the location of the line under the array.

Note: Unlike most of our products, these sensor arrays do not ship with any headers or connectors included, so you will need to supply your own or solder wires directly to the board to use it. See our selection of male headers, female headers, and pre-crimped wires for various connector options.

Each sensor on the A versions outputs its reflectance measurement as an analog voltage that can range from 0 V when the reflectance is very strong to VCC when the reflectance is very weak. The typical sequence for reading a sensor is:

Use a microcontroller’s analog-to-digital converter (ADC) to measure the voltages.

Use a comparator with an adjustable threshold to convert each analog voltage into a digital (i.e. black/white) signal that can be read by the digital I/O line of a microcontroller.

Connect each output directly to a digital I/O line of a microcontroller and rely upon its logic threshold.

This last method will work if you are able to get high reflectance from your white surface as depicted in the left image, but will probably fail if you have a lower-reflectance signal profile like the one on the right.

QTR-1A output 1/8" away from a spinning white disk with a black line on it.

QTR-1A output 3/8" away from a spinning white disk with a black line on it.

Each sensor on the RC versions requires a digital I/O line capable of driving the output line high and then measuring the time for the output voltage to decay. The typical sequence for reading a sensor is:

QTR-1RC output (yellow) when 1/8" above a black line and microcontroller timing of that output (blue).

QTR-1RC output (yellow) when 1/8" above a white surface and microcontroller timing of that output (blue).

Turn on IR LEDs (optional).

Set the I/O line to an output and drive it high.

Allow at least 10 μs for the sensor output to rise.

Make the I/O line an input (high impedance).

Measure the time for the voltage to decay by waiting for the I/O line to go low.

Turn off IR LEDs (optional).

These steps can typically be executed in parallel on multiple I/O lines.

With a strong reflectance, the decay time can be as low as a few microseconds; with no reflectance, the decay time can be up to a few milliseconds. The exact time of the decay depends on your microcontroller’s I/O line characteristics. Meaningful results can be available within 1 ms in typical cases (i.e. when not trying to measure subtle differences in low-reflectance scenarios), allowing up to 1 kHz sampling of all sensors. If lower-frequency sampling is sufficient, you can achieve substantial power savings by turning off the LEDs. For example, if a 100 Hz sampling rate is acceptable, the LEDs can be off 90% of the time, lowering average current consumption from 125 mA to 13 mA.

These reflectance sensor arrays maintain a constant current through their IR emitters, keeping the emitters’ brightness constant, independent of the supply voltage (2.9 V to 5.5 V). The emitters can be controlled with the board’s CTRL pins, and the details of the control depends on the array size and density:

HD units with 5 or more sensors and MD units with 11 or more sensors have two emitter control pins: CTRL ODD and CTRL EVEN. By default, these are connected together with a 1 kΩ resistor and pulled up, turning on all the emitters by default and allowing them to be controlled with a signal on either pin, but the CTRL ODD and CTRL EVEN pins can be driven separately for independent control of the odd-numbered and even-numbered emitters.

MD units with 3-10 sensors also have two emitter control pins since these are made by only populating every other sensor on an HD board, but only the CTRL ODD pin will have an effect on these versions (it is not possible to independently control alternate emitters).

HD units with 4 or fewer sensors and MD units with 2 or fewer sensors have a single CTRL pin that controls all of the emitters.

Driving a CTRL pin low for at least 1 ms turns off the associated emitter LEDs, while driving it high (or allowing the board to pull it high) turns on the emitters with the board’s default (full) current, which is 30 mA for “QTR” versions and 3.5 mA for “QTRX” versions. For more advanced use, the CTRL pin can be pulsed low to cycle the associated emitters through 32 dimming levels.

Demo of IR LED dimming and independent even/odd control on the QTR-HD-07x (as seen through an old digital camera that can see IR).

Demo of IR LED dimming and independent even/odd control on the QTRX-HD-07x (as seen through an old digital camera that can see IR).

To send a pulse, you should drive the CTRL pin low for at least 0.5 μs (but no more than 300 μs), then high for at least 0.5 μs; (it should remain high after the last pulse). Each pulse causes the driver to advance to the next dimming level, wrapping around to 100% after the lowest-current level. Each dimming level corresponds to a 3.33% reduction in current, except for the last three levels, which represent a 1.67% reduction, as shown in the table below. Note that turning the LEDs off with a >1 ms pulse and then back on resets them to full current.

For example, to reduce the emitter current to 50%, you would apply 15 low pulses to the CTRL pin and then keep it high after the last pulse.