This is the SparkFun MOSFET Power Control Kit, a breakout PTH soldering kit for for the RFP30N06LE N-Channel MOSFET. This kit is extremely simple to assemble with only 10 pins to solder. If you are looking for a little more control over projects that require a little more power than normal but need a better way than your breadboard, this kit is perfect for you

Included in each kit is a SparkFun MOSFET Power Control PCB, two screw terminals (one 2-pin and one 3-pin), a 10k resistor, and a single RFP30N06LE MOSFET. What we really like about this particular MOSFET is that it’s very common and offers very low on-resistance with a control (gate) voltage that is compatible with any 3-5V microcontroller or mechanical switch. This allows you to control high-power devices with very low-power control mechanisms.

Note: While the MOSFET is rated to 60V 30A, the circuit board traces are only rated to 3.5A.

Includes

1x SparkFun MOSFET Power Control PCB

1x RFP30N06LE MOSFET

1x 2-pin screw terminal

1x 3-pin screw terminal

1x 10k resistor

This tiny breakout board features the ADMP401 MEMS microphone. One of the key advantages to this breakout and microphone is the bottom ported input. This means the microphone’s input can fit flush against the enclosure of your project. Plus you will not have to deal with trying to solder the microphone’s wacky footprint. Wootness!

The amplifier on the breakout has a gain of 67 and more than meets the bandwidth requirements of the mic. The amplifier’s AUD output will float at one half Vcc when no sound is being picked up. The amplifier produces a peak-to-peak output of about 200mV when the microphone is held at arms length and is being talked into at normal conversational volume levels. So the AUD output can easily be connected to the ADC of a micro.

Get Started with the ADMP401 Breakout Guide

Features

-3dB roll off at 100Hz and 15kHz

1.5 to 3.3VDC supply voltage

Should comfortably output 40mW

SNR of -62dBA

The Nokia 5110 is a basic graphic LCD screen for lots of applications. It was originally intended to be used as a cell phone screen. This one is mounted on an easy to solder PCB.

It uses the PCD8544 controller, which is the same used in the Nokia 3310 LCD. The PCD8544 is a low power CMOS LCD controller/driver, designed to drive a graphic display of 48 rows and 84 columns. All necessary functions for the display are provided in a single chip, including on-chip generation of LCD supply and bias voltages, resulting in a minimum of external components and low power consumption. The PCD8544 interfaces to microcontrollers through a serial bus interface.

Note: There may be small blemishes on these screens as they are surplus.

Note: Your screen may or may not have a diode on the PCB. It does not affect performance and will vary depending on our shipment.

Features

45x45mm

The Big Easy Driver, designed by Brian Schmalz, is a stepper motor driver board for bi-polar stepper motors up to a max 2A/phase. It is based on the Allegro A4988 stepper driver chip. It’s the next version of the popular Easy Driver board.

Each Big Easy Driver can drive up to a max of 2A per phase of a bi-polar stepper motor. It is a chopper microstepping driver which defaults to 16 step microstepping mode. It can take a maximum motor drive voltage of around 30V, and includes on-board 5V/3.3V regulation, so only one supply is necessary. Although this board should be able to run most systems without active cooling while operating at 1.4-1.7A/phase, a heatsink is required for loads approaching 2A/phase. You can find the recommended heatsink in the related items below.

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

Features

Bi-polar Microstepping Driver

2A/Phase Max

1.4-1.7A/Phase w/o Heatsink

Max Motor Drive Voltage: 30V

On-board 5V/3.3V Regulation

The EasyDriver is a simple to use stepper motor driver, compatible with anything that can output a digital 0 to 5V pulse (or 0 to 3.3V pulse if you solder SJ2 closed on the EasyDriver). The EasyDriver requires a 6V to 30V supply to power the motor and can power any voltage of stepper motor. The EasyDriver has an on board voltage regulator for the digital interface that can be set to 5V or 3.3V. Connect a 4-wire stepper motor and a microcontroller and you’ve got precision motor control! EasyDriver drives bi-polar motors, and motors wired as bi-polar. I.e. 4,6, or 8 wire stepper motors.

This EasyDriver V4.5 has been co-designed with Brian Schmalz. It provides much more flexibility and control over your stepper motor, when compared to older versions. The microstep select (MS1 and MS2) pins of the A3967 are broken out allowing adjustments to the microstepping resolution. The sleep and enable pins are also broken out for further control.

Note: Do not connect or disconnect a motor while the driver is energized. This will cause permanent damage to the A3967 IC.

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

Features

A3967 Microstepping Driver

MS1 and MS2 pins broken out to change microstepping resolution to full, half, quarter and eighth steps (defaults to eighth)

Compatible with 4, 6, and 8 wire stepper motors of any voltage

Adjustable current control from 150mA/phase to 700mA/phase

Power supply range from 6V to 30V. The higher the voltage, the higher the torque at high speeds

*BZZZZZZZZZZ* Feel that? That's your little buzzing motor, and for any haptic feedback project you'll want to pick up a few of them. These vibe motors are tiny discs, completely sealed up so they're easy to use and embed.Two wires are used to control/power the vibe. Simply provide power from a battery or microcontroller pin (red is positive, blue is negative) and it will buzz away. Works from 2V up to 5V, higher voltages result in more current draw but also a stronger vibration.If you want to reduce the current draw/strength (for example, to control it directly from an Arduino pin) try putting a resistor (100 to 1000 ohms) in series. For full power control, a small PN2222 transistor can control a motor easily, some experimentation may be required!

Vibrating Mini Motor Disc (6:47)

LV-EZ4 Maxbotix Ultrasonic Rangefinder provides very short to long-range detection and ranging, in an incredibly small package. It can detect objects from 0-inches to 254-inches (6.45-meters) and provides sonar range information from 6-inches out to 254-inches with 1-inch resolution. (Objects from 0 inches to 6-inches range as 6-inches.) The interface output formats included are pulse width output (PWM), analog voltage output (Vcc/512 volts per inch), and serial digital output (9600 baud).

A good sensor for when a Sharp IR distance sensor won't cut it. For example of using this with an Arduino, see the Halloween Pumpkin project.

Many applications require a narrower beam or lower sensitivity than the LV MaxSonar EZ1. Consequently, MaxBotix is offering the EZ2, EZ3, & EZ4 with progressively narrower beam angles allowing the sensor to match the application.

LV-EZ4 Data Sheet / Product Information Guide is available here.

The different LV models have different beam width patterns, check this image for a comparison of all the LV model beam patterns.For higher sensitivity, check out the HR-LV models - they have up to 1mm sensitivity and 5 meter range!

This compact sonar range finder by Maxbotix detects objects from 0 to 6.45 m (21.2 ft) with a resolution of 2.5 cm (1") for distances beyond 15 cm (6"). Unlike other sonar range finders, the LV-MaxSonar has virtually no dead zone: it can detect even small objects up to and touching the front sensor face!The EZ0, EZ1, EZ2, EZ3, and EZ4 versions have progressively narrower beam angles.

MaxBotix ultrasonic sensor line comparison chart.

The Maxbotix LV-MaxSonar-EZ family of sonar range finders offers very short- to long-range detection and ranging in an incredibly small package with ultra-low power consumption. The LV-MaxSonar-EZ detects objects from 0 to 6.45 meters (21.2 feet) and provides sonar range information beyond 15 cm (6") with a resolution of 2.5 cm resolution (1 in). Objects between 0 and 15 cm range as 15 cm. The sensor provides three output interfaces, all of which are active simultaneously: digital pulse width output, analog voltage output, and asynchronous serial digital output. The LV-MaxSonar is available in five factory-calibrated beam patterns (EZ0-4).

For a higher-resolution, longer-range version, please consider the XL-MaxSonar-EZ and XL-MaxSonar-AE families of distance sensors.

Small and light: 0.870" x 0.785" x 0.645" (2.2 x 2.0 x 1.6 cm), 0.15 oz (4.3 g)

Long range detection: 0 – 6.45 m (21.2 ft)

No dead zone (detections from 0 to 6" are output as 6")

Resolution of 1" (2.5 cm)

Low typical current consumption: 2 mA

Runs on 2.5 – 5.5 V

42 kHz ultrasonic sensor

20 Hz reading rate

Free-run or triggered operation

Three interfaces (all are active simultaneously):

Serial output: asynchronous, logic-level, inverted, 9600 bps 8N1

Analog output: (Vcc/512) / inch (10 mV/inch when input voltage Vcc = 5 V)

Pulse width output: 147 μs/inch

Serial output: asynchronous, logic-level, inverted, 9600 bps 8N1

Analog output: (Vcc/512) / inch (10 mV/inch when input voltage Vcc = 5 V)

Pulse width output: 147 μs/inch

Since there are 15 members of the XL- and LV-MaxSonar acoustic distance sensor family, we recommend using the Maxbotix sonar range finder selection guide when choosing a acoustic range sensor for your application. There are 5 different beam configurations for the LV-MaxSonar family (EZ0 – EZ4), each pictured below.

LV-MaxSonar-EZ beam patterns (range shown on 1-foot grid to various diameter dowels)

Maxbotix LV-MaxSonar-EZ0 MB1000 beam characteristics:

Maxbotix LV-MaxSonar-EZ1 MB1010 beam characteristics:

Maxbotix LV-MaxSonar-EZ2 MB1020 beam characteristics:

Maxbotix LV-MaxSonar-EZ3 MB1030 beam characteristics:

Maxbotix LV-MaxSonar-EZ4 MB1040 beam characteristics:

People often buy this product together with:

This compact sonar range finder by Maxbotix detects objects from 0 to 6.45 m (21.2 ft) with a resolution of 2.5 cm (1") for distances beyond 15 cm (6"). Unlike other sonar range finders, the LV-MaxSonar has virtually no dead zone: it can detect even small objects up to and touching the front sensor face!The EZ0, EZ1, EZ2, EZ3, and EZ4 versions have progressively narrower beam angles.

MaxBotix ultrasonic sensor line comparison chart.

The Maxbotix LV-MaxSonar-EZ family of sonar range finders offers very short- to long-range detection and ranging in an incredibly small package with ultra-low power consumption. The LV-MaxSonar-EZ detects objects from 0 to 6.45 meters (21.2 feet) and provides sonar range information beyond 15 cm (6") with a resolution of 2.5 cm resolution (1 in). Objects between 0 and 15 cm range as 15 cm. The sensor provides three output interfaces, all of which are active simultaneously: digital pulse width output, analog voltage output, and asynchronous serial digital output. The LV-MaxSonar is available in five factory-calibrated beam patterns (EZ0-4).

For a higher-resolution, longer-range version, please consider the XL-MaxSonar-EZ and XL-MaxSonar-AE families of distance sensors.

Small and light: 0.870" x 0.785" x 0.645" (2.2 x 2.0 x 1.6 cm), 0.15 oz (4.3 g)

Long range detection: 0 – 6.45 m (21.2 ft)

No dead zone (detections from 0 to 6" are output as 6")

Resolution of 1" (2.5 cm)

Low typical current consumption: 2 mA

Runs on 2.5 – 5.5 V

42 kHz ultrasonic sensor

20 Hz reading rate

Free-run or triggered operation

Three interfaces (all are active simultaneously):

Serial output: asynchronous, logic-level, inverted, 9600 bps 8N1

Analog output: (Vcc/512) / inch (10 mV/inch when input voltage Vcc = 5 V)

Pulse width output: 147 μs/inch

Serial output: asynchronous, logic-level, inverted, 9600 bps 8N1

Analog output: (Vcc/512) / inch (10 mV/inch when input voltage Vcc = 5 V)

Pulse width output: 147 μs/inch

Since there are 15 members of the XL- and LV-MaxSonar acoustic distance sensor family, we recommend using the Maxbotix sonar range finder selection guide when choosing a acoustic range sensor for your application. There are 5 different beam configurations for the LV-MaxSonar family (EZ0 – EZ4), each pictured below.

LV-MaxSonar-EZ beam patterns (range shown on 1-foot grid to various diameter dowels)

Maxbotix LV-MaxSonar-EZ0 MB1000 beam characteristics:

Maxbotix LV-MaxSonar-EZ1 MB1010 beam characteristics:

Maxbotix LV-MaxSonar-EZ2 MB1020 beam characteristics:

Maxbotix LV-MaxSonar-EZ3 MB1030 beam characteristics:

Maxbotix LV-MaxSonar-EZ4 MB1040 beam characteristics:

People often buy this product together with:

The HRLV-MaxSonar-EZ sensor line is the most cost-effective solution for applications where precision range-finding, low-voltage operation, space saving, and low-cost are needed.

The HRLV-MaxSonar-EZ sensor line provides high accuracy and high resolution ultrasonic proximity detection and ranging in air, in a package less than one cubic inch. This sensor line features 1mm resolution, target-size and operating-voltage compensation for improved accuracy, superior rejection of outside noise sources, internal speed-of-sound temperature compensation and optional external speed-of-sound temperature compensation. This ultrasonic sensor detects objects from 1mm to 5meters, senses range to objects from 30cm to 5meters, with large objects closer than 30cm typically reported as 30cm. The interface output formats are pulse width, analog voltage, and serial digital in either RS232 or TTL. Factory calibration is standard.

A good sensor for when a Sharp IR distance sensor won't cut it. For example of using this with an Arduino, see the Halloween Pumpkin project.

HRLV-EZ0 Data Sheet / Product Information Guide is available here. By default this sensor outputs RS-232 logic level data, to use it in TTL logic mode, solder closed the square jumper on the back.

The different HRLV models have different beam width patterns, check this image for a comparison of all the HRLV model beam patterns. If you don't need high sensitivity, or want a longer range, check out the LV models - They are meant for up to 6.5 meter distances

The HRLV-MaxSonar-EZ sensor line is the most cost-effective solution for applications where precision range-finding, low-voltage operation, space saving, and low-cost are needed.

The HRLV-MaxSonar-EZ sensor line provides high accuracy and high resolution ultrasonic proximity detection and ranging in air, in a package less than one cubic inch. This sensor line features 1mm resolution, target-size and operating-voltage compensation for improved accuracy, superior rejection of outside noise sources, internal speed-of-sound temperature compensation and optional external speed-of-sound temperature compensation. This ultrasonic sensor detects objects from 1mm to 5meters, senses range to objects from 30cm to 5meters, with large objects closer than 30cm typically reported as 30cm. The interface output formats are pulse width, analog voltage, and serial digital in either RS232 or TTL. Factory calibration is standard.

A good sensor for when a Sharp IR distance sensor won't cut it. For example of using this with an Arduino, see the Halloween Pumpkin project.

HRLV-EZ1 Data Sheet / Product Information Guide is available here. By default this sensor outputs RS-232 logic level data, to use it in TTL logic mode, solder closed the square jumper on the back.

The different HRLV models have different beam width patterns, check this image for a comparison of all the HRLV model beam patterns. If you don't need high sensitivity, or want a longer range, check out the LV models - They are meant for up to 6.5 meter distances

The HRLV-MaxSonar-EZ sensor line is the most cost-effective solution for applications where precision range-finding, low-voltage operation, space saving, and low-cost are needed.

The HRLV-MaxSonar-EZ sensor line provides high accuracy and high resolution ultrasonic proximity detection and ranging in air, in a package less than one cubic inch. This sensor line features 1mm resolution, target-size and operating-voltage compensation for improved accuracy, superior rejection of outside noise sources, internal speed-of-sound temperature compensation and optional external speed-of-sound temperature compensation. This ultrasonic sensor detects objects from 1mm to 5meters, senses range to objects from 30cm to 5meters, with large objects closer than 30cm typically reported as 30cm. The interface output formats are pulse width, analog voltage, and serial digital in either RS232 or TTL. Factory calibration is standard.

A good sensor for when a Sharp IR distance sensor won't cut it. For example of using this with an Arduino, see the Halloween Pumpkin project.

HRLV-EZ4 Data Sheet / Product Information Guide is available here. By default this sensor outputs RS-232 logic level data, to use it in TTL logic mode, solder closed the square jumper on the back.

The different HRLV models have different beam width patterns, check this image for a comparison of all the HRLV model beam patterns. If you don't need high sensitivity, or want a longer range, check out the LV models - They are meant for up to 6.5 meter distances

The GP2Y0A60SZ distance sensor from Sharp offers a wide detection range of 4″ to 60″ (10 cm to 150 cm) and a high update rate of 60 Hz. The distance is indicated by an analog voltage, so only a single analog input is required to interface with the module. The sensor ships installed on our compact carrier board, which makes it easy to integrate this great sensor into your project, and is configured for 3V mode.

Pololu Carrier with Sharp GP2Y0A60SZLF Analog Distance Sensor 10-150cm, front view with dimensions.

Sharp’s distance sensors are a popular choice for many projects that require accurate distance measurements. This particular sensor is small and affordable, making it an attractive alternative to sonar rangefinders, while its wide sensing range and resistance to interference from ambient IR set it apart from other IR distance sensors. It consists of a Sharp GP2Y0A60SZLF module installed on our compact carrier board, which includes all of the external components required to make it work and provides a 0.1″ pin spacing that is compatible with standard connectors, solderless breadboards, and perfboards. With an ability to measure distances from as close as four inches to as far as five feet (10 cm to 150 cm), this sensor has the widest range of any of our Sharp distance sensors, and its 60 Hz update rate is more than twice that of Sharp’s older GP2Y0A02YK0F analog distance sensor that has a similar sensing range.

Interfacing to most microcontrollers is straightforward: the single analog output, OUT, can be connected to an analog-to-digital converter for taking distance measurements, or the output can be connected to a comparator for threshold detection. The sensor automatically updates the output approximately every 16 ms. The enable pin, EN, can be driven low to disable the IR emitter and put the sensor into a low-current stand-by mode. This pin is pulled high on the carrier board through a 10 kΩ pull-up resistor to enable the sensor by default.

A 1×4 strip of 0.1″ header pins and a 1×4 strip of 0.1″ right-angle header pins are included, as shown in the picture below. You can solder the header strip of your choice to the board for use with custom cables or solderless breadboards, or you can solder wires directly to the board itself for more compact installations. The board features one 0.125″ mounting hole that works with #4 or M3 screws (not included); if you do not need the mounting hole, you can cut that part of the board off to reduce its size.

The GP2Y0A60SZ supports two operating modes: 5V and 3V. In 5V mode, the recommended operating voltage is 2.7 V to 5.5 V, and the output voltage differential over the full distance range is approximately 3 V, varying from around 3.6 V at 10 cm to 0.6 V at 150 cm. In 3V mode, the recommended operating voltage is 2.7 V to 3.6 V, and the output voltage differential over the full distance range is approximately 1.6 V, varying from around 1.9 V at 10 cm to 0.3 V at 150 cm. The GP2Y0A60SZ datasheet (701k pdf) contains a plot of analog output voltage as a function of the distance for the two modes.

Our GP2Y0A60 carrier board is available configured for 5V mode or configured for 3V mode:

The only difference between the two versions is the presence or absence of a zero ohm resistor as shown in the picture above (the component location is marked by a rectangle on the silkscreen). You can convert a 5V version to 3V by removing the resistor, and you can convert a 3V version to 5V by shorting across the two pads.

Note that the 5V version can be powered all the way down to 2.7 V, and the relationship between the sensor output voltage and distance is mostly independent of the supply voltage. The main drawback to powering the 5V version at a lower voltage is the output voltage will not exceed the supply voltage, so the effective minimum detection distance might increase (i.e. for distances that would result in output voltages above your supply voltage, the output will instead be capped at the supply voltage). On the other hand, if you mostly care about measuring distances closer to the maximum end of the range, you could benefit from the increased output voltage differential of the 5V version even if you are only powering it at 3.3 V.

Operating voltage:

5V version: 2.7 V to 5.5 V

3V version: 2.7 V to 3.6 V

5V version: 2.7 V to 5.5 V

3V version: 2.7 V to 3.6 V

Average current consumption: 33 mA (typical)

Distance measuring range: 10 cm to 150 cm (4″ to 60″)

Output type: analog voltage

Output voltage differential over distance range:

5V version: 3.0 V (typical)

3V version: 1.6 V (typical)

5V version: 3.0 V (typical)

3V version: 1.6 V (typical)

Update period: 16.5 ± 4 ms

Enable pin can optionally be used to disable the emitter and save power

Size without header pins: 33 mm × 10.4 mm × 10.2 mm (1.3″ × 0.41″ × 0.4″)

Weight without header pins: 2.5 g (0.09 oz)

The above schematic shows the additional components the carrier board incorporates to make the GP2Y0A60SZLF easier to use. This schematic is also available as a downloadable pdf (142k pdf).

We carry several other Sharp distance sensors, including the shorter range Sharp GP2Y0A41SK0F analog distance sensor (4 – 30 cm) and Sharp GP2Y0A21YK0F analog distance sensor (10 – 80 cm). With regard to performance, this GP2Y0A60SZ is most similar to the Sharp GP2Y0A02YK0F analog distance sensor (20 – 150 cm), but the GP2Y0A60SZ offers a lower minimum detection distance and more than twice the sampling rate in a much smaller package:

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

We also carry three digital Sharp distance sensors that have lower minimum detection distances, quicker response times, lower current draws, and much smaller packages; they are available with a 5 cm, 10 cm, or 15 cm maximum detection distance and simply tell you if something is in their detection range, not how far away it is.

A variety of Sharp distance sensors.

People often buy this product together with:

The GP2Y0A60SZ distance sensor from Sharp offers a wide detection range of 4″ to 60″ (10 cm to 150 cm) and a high update rate of 60 Hz. The distance is indicated by an analog voltage, so only a single analog input is required to interface with the module. The sensor ships installed on our compact carrier board, which makes it easy to integrate this great sensor into your project, and is configured for 5V mode.

Pololu Carrier with Sharp GP2Y0A60SZLF Analog Distance Sensor 10-150cm, front view with dimensions.

Sharp’s distance sensors are a popular choice for many projects that require accurate distance measurements. This particular sensor is small and affordable, making it an attractive alternative to sonar rangefinders, while its wide sensing range and resistance to interference from ambient IR set it apart from other IR distance sensors. It consists of a Sharp GP2Y0A60SZLF module installed on our compact carrier board, which includes all of the external components required to make it work and provides a 0.1″ pin spacing that is compatible with standard connectors, solderless breadboards, and perfboards. With an ability to measure distances from as close as four inches to as far as five feet (10 cm to 150 cm), this sensor has the widest range of any of our Sharp distance sensors, and its 60 Hz update rate is more than twice that of Sharp’s older GP2Y0A02YK0F analog distance sensor that has a similar sensing range.

Interfacing to most microcontrollers is straightforward: the single analog output, OUT, can be connected to an analog-to-digital converter for taking distance measurements, or the output can be connected to a comparator for threshold detection. The sensor automatically updates the output approximately every 16 ms. The enable pin, EN, can be driven low to disable the IR emitter and put the sensor into a low-current stand-by mode. This pin is pulled high on the carrier board through a 10 kΩ pull-up resistor to enable the sensor by default.

A 1×4 strip of 0.1″ header pins and a 1×4 strip of 0.1″ right-angle header pins are included, as shown in the picture below. You can solder the header strip of your choice to the board for use with custom cables or solderless breadboards, or you can solder wires directly to the board itself for more compact installations. The board features one 0.125″ mounting hole that works with #4 or M3 screws (not included); if you do not need the mounting hole, you can cut that part of the board off to reduce its size.

The GP2Y0A60SZ supports two operating modes: 5V and 3V. In 5V mode, the recommended operating voltage is 2.7 V to 5.5 V, and the output voltage differential over the full distance range is approximately 3 V, varying from around 3.6 V at 10 cm to 0.6 V at 150 cm. In 3V mode, the recommended operating voltage is 2.7 V to 3.6 V, and the output voltage differential over the full distance range is approximately 1.6 V, varying from around 1.9 V at 10 cm to 0.3 V at 150 cm. The GP2Y0A60SZ datasheet (701k pdf) contains a plot of analog output voltage as a function of the distance for the two modes.

Our GP2Y0A60 carrier board is available configured for 5V mode or configured for 3V mode:

The only difference between the two versions is the presence or absence of a zero ohm resistor as shown in the picture above (the component location is marked by a rectangle on the silkscreen). You can convert a 5V version to 3V by removing the resistor, and you can convert a 3V version to 5V by shorting across the two pads.

Note that the 5V version can be powered all the way down to 2.7 V, and the relationship between the sensor output voltage and distance is mostly independent of the supply voltage. The main drawback to powering the 5V version at a lower voltage is the output voltage will not exceed the supply voltage, so the effective minimum detection distance might increase (i.e. for distances that would result in output voltages above your supply voltage, the output will instead be capped at the supply voltage). On the other hand, if you mostly care about measuring distances closer to the maximum end of the range, you could benefit from the increased output voltage differential of the 5V version even if you are only powering it at 3.3 V.

Operating voltage:

5V version: 2.7 V to 5.5 V

3V version: 2.7 V to 3.6 V

5V version: 2.7 V to 5.5 V

3V version: 2.7 V to 3.6 V

Average current consumption: 33 mA (typical)

Distance measuring range: 10 cm to 150 cm (4″ to 60″)

Output type: analog voltage

Output voltage differential over distance range:

5V version: 3.0 V (typical)

3V version: 1.6 V (typical)

5V version: 3.0 V (typical)

3V version: 1.6 V (typical)

Update period: 16.5 ± 4 ms

Enable pin can optionally be used to disable the emitter and save power

Size without header pins: 33 mm × 10.4 mm × 10.2 mm (1.3″ × 0.41″ × 0.4″)

Weight without header pins: 2.5 g (0.09 oz)

The above schematic shows the additional components the carrier board incorporates to make the GP2Y0A60SZLF easier to use. This schematic is also available as a downloadable pdf (142k pdf).

We carry several other Sharp distance sensors, including the shorter range Sharp GP2Y0A41SK0F analog distance sensor (4 – 30 cm) and Sharp GP2Y0A21YK0F analog distance sensor (10 – 80 cm). With regard to performance, this GP2Y0A60SZ is most similar to the Sharp GP2Y0A02YK0F analog distance sensor (20 – 150 cm), but the GP2Y0A60SZ offers a lower minimum detection distance and more than twice the sampling rate in a much smaller package:

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

We also carry three digital Sharp distance sensors that have lower minimum detection distances, quicker response times, lower current draws, and much smaller packages; they are available with a 5 cm, 10 cm, or 15 cm maximum detection distance and simply tell you if something is in their detection range, not how far away it is.

A variety of Sharp distance sensors.

People often buy this product together with:

The Pololu AltIMU-10 v5 is an inertial measurement unit (IMU) and altimeter that features the same LSM6DS33 gyro and accelerometer and LIS3MDL magnetometer as the MinIMU-9 v5, and adds an LPS25H digital barometer. An I²C interface accesses ten independent pressure, rotation, acceleration, and magnetic measurements that can be used to calculate the sensor’s altitude and absolute orientation. The board operates from 2.5 to 5.5 V and has a 0.1″ pin spacing.

The Pololu AltIMU-10 v5 is a compact (1.0″ × 0.5″) board that combines ST’s LSM6DS33 3-axis gyroscope and 3-axis accelerometer, LIS3MDL 3-axis magnetometer, and LPS25H digital barometer to form an inertial measurement unit (IMU) and altimeter; we therefore recommend careful reading of the LSM6DS33 datasheet (1MB pdf), LIS3MDL datasheet (2MB pdf), and LPS25H datasheet (1MB pdf) before using this product. These sensors are great ICs, but their small packages make them difficult for the typical student or hobbyist to use. They also operate at voltages below 3.6 V, which can make interfacing difficult for microcontrollers operating at 5 V. The AltIMU-10 v5 addresses these issues by incorporating additional electronics, including a voltage regulator and a level-shifting circuit, while keeping the overall size as compact as possible. The board ships fully populated with its SMD components, including the LSM6DS33, LIS3MDL, and LPS25H, as shown in the product picture.

Compared to the previous AltIMU-10 v4, the v5 version uses newer MEMS sensors that provide some increases in accuracy (lower noise and zero-rate offsets). The AltIMU-10 v5 is pin-compatible with the AltIMU-10 v4, but because it uses different sensor chips, software written for older IMU versions will need to be changed to work with the v5.

The AltIMU-10 v5 is also pin-compatible with the MinIMU-9 v5 and offers the same functionality augmented by a digital barometer that can be used to obtain pressure and altitude measurements. It includes a second mounting hole and is only 0.2″ longer than the MinIMU-9 v5. Any code written for the MinIMU-9 v5 should also work with the AltIMU-10 v5.

Side-by-side comparison of the MinIMU-9 v5 with the AltIMU-10 v5.

The LSM6DS33, LIS3MDL, and LPS25H have many configurable options, including dynamically selectable sensitivities for the gyro, accelerometer, and magnetometer and selectable resolutions for the barometer. Each sensor also has a choice of output data rates. The three ICs can be accessed through a shared I²C/TWI interface, allowing the sensors to be addressed individually via a single clock line and a single data line. Additionally, a slave address configuration pin allows users to change the sensors’ I²C addresses and have two AltIMUs connected on the same I²C bus. (For additional information, see the I²C Communication section below.)

The nine independent rotation, acceleration, and magnetic readings provide all the data needed to make an attitude and heading reference system (AHRS), and readings from the absolute pressure sensor can be easily converted to altitudes, giving you a total of ten independent measurements (sometimes called 10DOF). With an appropriate algorithm, a microcontroller or computer can use the data to calculate the orientation and height of the AltIMU board. The gyro can be used to very accurately track rotation on a short timescale, while the accelerometer and compass can help compensate for gyro drift over time by providing an absolute frame of reference. The respective axes of the two chips are aligned on the board to facilitate these sensor fusion calculations. (For an example of such a system using an Arduino, see the picture below and the Sample Code section at the bottom of this page.)

Visualization of AHRS orientation calculated from MinIMU-9 readings.

The carrier board includes a low-dropout linear voltage regulator that provides the 3.3 V required by the LSM6DS33, LIS3MDL, and LPS25H, allowing the module to be powered from a single 2.5 V to 5.5 V supply. The regulator output is available on the VDD pin and can supply almost 150 mA to external devices. The breakout board also includes a circuit that shifts the I²C clock and data lines to the same logic voltage level as the supplied VIN, making it simple to interface the board with 5 V systems. The board’s 0.1″ pin spacing makes it easy to use with standard solderless breadboards and 0.1″ perfboards.

Specifications

Dimensions: 1.0″ × 0.5″ × 0.1″ (25 mm × 13 mm × 3 mm)

Weight without header pins: 0.8 g (0.03 oz)

Operating voltage: 2.5 V to 5.5 V

Supply current: 5 mA

Output format (I²C):

Gyro: one 16-bit reading per axis

Accelerometer: one 16-bit reading per axis

Magnetometer: one 16-bit reading per axis

Barometer: 24-bit pressure reading (4096 LSb/mbar)

Gyro: one 16-bit reading per axis

Accelerometer: one 16-bit reading per axis

Magnetometer: one 16-bit reading per axis

Barometer: 24-bit pressure reading (4096 LSb/mbar)

Sensitivity range:

Gyro: ±125, ±245, ±500, ±1000, or ±2000°/s

Accelerometer: ±2, ±4, ±8, or ±16 g

Magnetometer: ±4, ±8, ±12, or ±16 gauss

Barometer: 260 mbar to 1260 mbar (26 kPa to 126 kPa)

Gyro: ±125, ±245, ±500, ±1000, or ±2000°/s

Accelerometer: ±2, ±4, ±8, or ±16 g

Magnetometer: ±4, ±8, ±12, or ±16 gauss

Barometer: 260 mbar to 1260 mbar (26 kPa to 126 kPa)

Included Components

A 1×6 strip of 0.1″ header pins and a 1×5 strip of 0.1″ right-angle header pins are included, as shown in the picture below. You can solder the header strip of your choice to the board for use with custom cables or solderless breadboards or solder wires directly to the board itself for more compact installations. The board features two mounting holes that work with #2 or M2 screws (not included).

Connections

A minimum of four connections is necessary to use the AltIMU-10 v5: VIN, GND, SCL, and SDA. VIN should be connected to a 2.5 V to 5.5 V source, GND to 0 volts, and SCL and SDA should be connected to an I²C bus operating at the same logic level as VIN. (Alternatively, if you are using the board with a 3.3 V system, you can leave VIN disconnected and bypass the built-in regulator by connecting 3.3 V directly to VDD.)

Pololu AltIMU-10 v5 gyro, accelerometer, compass, and altimeter pinout.

Two Pololu AltIMU-10 v5 modules in a breadboard.

Pinout

The CS, data ready, and interrupt pins of the LSM6DS33, LIS3MDL, and LPS25H are not accessible on the AltIMU-10 v5. In particular, the absence of the CS pin means that the optional SPI interface of these ICs is not available. If you want these features, consider using our LSM6DS33 carrier, LIS3MDL carrier, and LPS25H carrier boards.

Schematic Diagram

The above schematic shows the additional components the carrier board incorporates to make the LSM6DS33, LIS3MDL, and LPS25H easier to use, including the voltage regulator that allows the board to be powered from a single 2.5 V to 5.5 V supply and the level-shifter circuit that allows for I²C communication at the same logic voltage level as VIN. This schematic is also available as a downloadable pdf: AltIMU-10 v5 schematic (119k pdf).

I²C Communication

The LSM6DS33’s gyro and accelerometer, the LIS3MDL’s magnetometer, and the LPS25H’s barometer can be queried and configured through the I²C bus. Each of the four sensors acts as a slave device on the same I²C bus (i.e. their clock and data lines are tied together to ease communication). Additionally, level shifters on the I²C clock (SCL) and data lines (SDA) enable I²C communication with microcontrollers operating at the same voltage as VIN (2.5 V to 5.5 V). A detailed explanation of the protocols used by each device can be found in the LSM6DS33 datasheet (1MB pdf), the LIS3MDL datasheet (2MB pdf), and the LPS25H datasheet (1MB pdf). More detailed information about I²C in general can be found in NXP’s I²C-bus specification (1MB pdf).

The LSM6DS33, LIS3MDL, and LPS25H each have separate slave addresses on the I²C bus. The board connects the slave address select pins (SA0 or SA1) of the three ICs together and pulls them all to VDD through a 10 kΩ resistor. You can drive the pin labeled SA0 low to change the slave address. This allows you to have two AltIMUs (or an AltIMU v5 and a MinIMU v5) connected on the same I²C bus. The following table shows the slave addresses of the sensors:

All three chips on the AltIMU-10 v5 are compliant with fast mode (400 kHz) I²C standards as well as with the normal mode.

We have written a basic LSM6DS33 Arduino library, LIS3MDL Arduino library, and LPS25H Arduino library that make it easy to interface the AltIMU-10 v5 with an Arduino or Arduino-compatible board like an A-Star. They also make it simple to configure the sensors and read the raw gyro, accelerometer, magnetometer, and pressure data.

For a demonstration of what you can do with this data, you can turn an Arduino connected to a AltIMU-10 v5 into an attitude and heading reference system, or AHRS, with this Arduino program. It uses the data from the AltIMU-10 v5 to calculate estimated roll, pitch, and yaw angles, and you can visualize the output of the AHRS with a 3D test program on your PC (as shown in a screenshot above). This software is based on the work of Jordi Munoz, William Premerlani, Jose Julio, and Doug Weibel.

The datasheets provide all the information you need to use the sensors on the AltIMU-10 v5, but picking out the important details can take some time. Here are some pointers for communicating with and configuring the LSM6DS33, LIS3MDL, and LPS25H that we hope will get you up and running a little bit faster:

The gyro, accelerometer, magnetometer, and pressure sensor are all in power-down mode by default. You have to turn them on by setting the correct configuration registers.

You can read or write multiple registers in the LIS3MDL or LPS25H with a single I²C command by asserting the most significant bit of the register address to enable address auto-increment.

The register address in the LSM6DS33 automatically increments during a multiple byte access, allowing you to read or write multiple registers in a single I²C command. Unlike how some other ST sensors work, the auto-increment is enabled by default; you can turn it off with the IF_INC field in the CTRL3_C register.

In addition to the datasheets, ST provides application notes for the LSM6DS33 (1MB pdf) and LIS3MDL (598k pdf) containing additional information and hints about using them.

We carry several inertial measurement and orientation sensors. The table below compares their capabilities:

People often buy this product together with:

The Pololu MinIMU-9 v5 is an inertial measurement unit (IMU) that packs an LSM6DS33 3-axis gyro and 3-axis accelerometer and an LIS3MDL 3-axis magnetometer onto a tiny 0.8″ × 0.5″ board. An I²C interface accesses nine independent rotation, acceleration, and magnetic measurements that can be used to calculate the sensor’s absolute orientation. The MinIMU-9 v5 board includes a voltage regulator and a level-shifting circuit that allow operation from 2.5 to 5.5 V, and the 0.1″ pin spacing makes it easy to use with standard solderless breadboards and 0.1″ perfboards.

The Pololu MinIMU-9 v5 is a compact (0.8″ × 0.5″) board that combines ST’s LSM6DS33 3-axis gyroscope and 3-axis accelerometer and LIS3MDL 3-axis magnetometer to form an inertial measurement unit (IMU); we therefore recommend careful reading of the LSM6DS33 datasheet (1MB pdf) and LIS3MDL datasheet (2MB pdf) before using this product. These sensors are great ICs, but their small packages make them difficult for the typical student or hobbyist to use. They also operate at voltages below 3.6 V, which can make interfacing difficult for microcontrollers operating at 5 V. The MinIMU-9 v5 addresses these issues by incorporating additional electronics, including a voltage regulator and a level-shifting circuit, while keeping the overall size as compact as possible. The board ships fully populated with its SMD components, including the LSM6DS33 and LIS3MDL, as shown in the product picture.

Compared to the previous MinIMU-9 v3, the v5 version uses newer MEMS sensors that provide some increases in accuracy (lower noise and zero-rate offsets). The MinIMU-9 v5 is pin-compatible with the MinIMU-9 v3, but because it uses different sensor chips, software written for older IMU versions will need to be changed to work with the v5.

The MinIMU-9 v5 is also pin-compatible with the AltIMU-10 v5, which offers the same functionality augmented by a digital barometer that can be used to obtain pressure and altitude measurements. The AltIMU includes a second mounting hole and is 0.2″ longer than the MinIMU. Any code written for the MinIMU-9 v5 should also work with the AltIMU-10 v5.

Side-by-side comparison of the MinIMU-9 v5 with the AltIMU-10 v5.

The LSM6DS33 and LIS3MDL have many configurable options, including dynamically selectable sensitivities for the gyro, accelerometer, and magnetometer. Each sensor also has a choice of output data rates. The two ICs can be accessed through a shared I²C/TWI interface, allowing the sensors to be addressed individually via a single clock line and a single data line. Additionally, a slave address configuration pin allows users to change the sensors’ I²C addresses and have two MinIMUs connected on the same I²C bus. (For additional information, see the I²C Communication section below.)

The nine independent rotation, acceleration, and magnetic readings (sometimes called 9DOF) provide all the data needed to make an attitude and heading reference system (AHRS). With an appropriate algorithm, a microcontroller or computer can use the data to calculate the orientation of the MinIMU board. The gyro can be used to very accurately track rotation on a short timescale, while the accelerometer and compass can help compensate for gyro drift over time by providing an absolute frame of reference. The respective axes of the two chips are aligned on the board to facilitate these sensor fusion calculations. (For an example of such a system using an Arduino, see the picture below and the Sample Code section at the bottom of this page.)

Visualization of AHRS orientation calculated from MinIMU-9 readings.

The carrier board includes a low-dropout linear voltage regulator that provides the 3.3 V required by the LSM6DS33 and LIS3MDL, allowing the module to be powered from a single 2.5 V to 5.5 V supply. The regulator output is available on the VDD pin and can supply almost 150 mA to external devices. The breakout board also includes a circuit that shifts the I²C clock and data lines to the same logic voltage level as the supplied VIN, making it simple to interface the board with 5 V systems. The board’s 0.1″ pin spacing makes it easy to use with standard solderless breadboards and 0.1″ perfboards.

Specifications

Dimensions: 0.8″ × 0.5″ × 0.1″ (20 mm × 13 mm × 3 mm)

Weight without header pins: 0.7 g (0.02 oz)

Operating voltage: 2.5 V to 5.5 V

Supply current: 5 mA

Output format (I²C):

Gyro: one 16-bit reading per axis

Accelerometer: one 16-bit reading per axis

Magnetometer: one 16-bit reading per axis

Gyro: one 16-bit reading per axis

Accelerometer: one 16-bit reading per axis

Magnetometer: one 16-bit reading per axis

Sensitivity range:

Gyro: ±125, ±245, ±500, ±1000, or ±2000°/s

Accelerometer: ±2, ±4, ±8, or ±16 g

Magnetometer: ±4, ±8, ±12, or ±16 gauss

Gyro: ±125, ±245, ±500, ±1000, or ±2000°/s

Accelerometer: ±2, ±4, ±8, or ±16 g

Magnetometer: ±4, ±8, ±12, or ±16 gauss

Included Components

A 1×6 strip of 0.1″ header pins and a 1×5 strip of 0.1″ right-angle header pins are included, as shown in the picture below. You can solder the header strip of your choice to the board for use with custom cables or solderless breadboards or solder wires directly to the board itself for more compact installations. The board features two mounting holes that work with #2 or M2 screws (not included).

Connections

A minimum of four connections is necessary to use the MinIMU-9 v5: VIN, GND, SCL, and SDA. VIN should be connected to a 2.5 V to 5.5 V source, GND to 0 volts, and SCL and SDA should be connected to an I²C bus operating at the same logic level as VIN. (Alternatively, if you are using the board with a 3.3 V system, you can leave VIN disconnected and bypass the built-in regulator by connecting 3.3 V directly to VDD.)

Pololu MinIMU-9 v5 gyro, accelerometer, and compass pinout.

Two Pololu MinIMU-9 v5 modules in a breadboard.

Pinout

The CS, data ready, and interrupt pins of the LSM6DS33 and LIS3MDL are not accessible on the MinIMU-9 v5. In particular, the absence of the CS pin means that the optional SPI interface of these ICs is not available. If you want these features, consider using our LSM6DS33 carrier and LIS3MDL carrier boards.

Schematic Diagram

The above schematic shows the additional components the carrier board incorporates to make the LSM6DS33 and LIS3MDL easier to use, including the voltage regulator that allows the board to be powered from a single 2.5 V to 5.5 V supply and the level-shifter circuit that allows for I²C communication at the same logic voltage level as VIN. This schematic is also available as a downloadable pdf: MinIMU-9 v5 schematic (106k pdf).

I²C Communication

The LSM6DS33’s gyro and accelerometer and the LIS3MDL’s magnetometer can be queried and configured through the I²C bus. Each of the three sensors acts as a slave device on the same I²C bus (i.e. their clock and data lines are tied together to ease communication). Additionally, level shifters on the I²C clock (SCL) and data lines (SDA) enable I²C communication with microcontrollers operating at the same voltage as VIN (2.5 V to 5.5 V). A detailed explanation of the protocols used by each device can be found in the LSM6DS33 datasheet (1MB pdf) and the LIS3MDL datasheet (2MB pdf). More detailed information about I²C in general can be found in NXP’s I²C-bus specification (1MB pdf).

The LSM6DS33 and LIS3MDL each have separate slave addresses on the I²C bus. The board connects the slave address select pins (SA0 or SA1) of the two ICs together and pulls them both to VDD through a 10 kΩ resistor. You can drive the pin labeled SA0 low to change the slave address. This allows you to have two MinIMUs (or a MinIMU v5 and an AltIMU v5) connected on the same I²C bus. The following table shows the slave addresses of the sensors:

Both chips on the MinIMU-9 v5 are compliant with fast mode (400 kHz) I²C standards as well as with the normal mode.

We have written a basic LSM6DS33 Arduino library and LIS3MDL Arduino library that make it easy to interface the MinIMU-9 v5 with an Arduino or Arduino-compatible board like an A-Star. They also make it simple to configure the sensors and read the raw gyro, accelerometer, and magnetometer data.

For a demonstration of what you can do with this data, you can turn an Arduino connected to a MinIMU-9 v5 into an attitude and heading reference system, or AHRS, with this Arduino program. It uses the data from the MinIMU-9 to calculate estimated roll, pitch, and yaw angles, and you can visualize the output of the AHRS with a 3D test program on your PC (as shown in a screenshot above). This software is based on the work of Jordi Munoz, William Premerlani, Jose Julio, and Doug Weibel.

The datasheets provide all the information you need to use the sensors on the MinIMU-9 v5, but picking out the important details can take some time. Here are some pointers for communicating with and configuring the LSM6DS33 and LIS3MDL that we hope will get you up and running a little bit faster:

The gyro, accelerometer, and magnetometer are all in power-down mode by default. You have to turn them on by setting the correct configuration registers.

You can read or write multiple registers in the LIS3MDL with a single I²C command by asserting the most significant bit of the register address to enable address auto-increment.

The register address in the LSM6DS33 automatically increments during a multiple byte access, allowing you to read or write multiple registers in a single I²C command. Unlike how some other ST sensors work, the auto-increment is enabled by default; you can turn it off with the IF_INC field in the CTRL3_C register.

In addition to the datasheets, ST provides application notes for the LSM6DS33 (1MB pdf) and LIS3MDL (598k pdf) containing additional information and hints about using them.

We carry several inertial measurement and orientation sensors. The table below compares their capabilities:

People often buy this product together with:

The LSM303C is a 6 Degrees of Freedom (6DOF) inertial measurement unit (IMU) in a single package, specifically developed as an eCompass device. Due to the IC housing a 3-axis accelerometer and a 3-axis magnetometer combined with its low cost, the LSM303C was perfect for us to create this small breakout board just for you! Each LSM303C Breakout has been designed to be super-flexible and can be configured specifically for many applications. The LSM303C Breakout can be configured to generate an interrupt signal for free-fall, motion detection and magnetic field detection!

The range of each sensor on the LSM303C is configurable: the accelerometer’s scale can be set to ±2g, ±4g, ±6g, or ±8g, while the magnetometer has full-scale range of ±16 gauss, and supports I2C and SPI communication.

Each pin has been broken out on the LSM303C, with 10 plated through-hole connections featuring power and I2C and SPI functionality, interrupt outputs, and accelerometer and magnetometer data out. Please keep in mind that the LSM303C is a 2.5V device so supplying voltages greater than ~4.8V can permanently damage the IC. As long as your Arduino has a 3.3V supply output, you shouldn’t need any extra level shifting.

Features

3 magnetic field channels and 3 acceleration channels

±16 gauss magnetic full scale

±2/±4/±8 g selectable acceleration full scale

16-bit data output

SPI / I2C serial interfaces

Analog supply voltage 1.9 V to 3.6 V

Power-down mode / low-power mode

Programmable interrupt generators for freefall, motion detection and magnetic field detection

Embedded temperature sensor

Embedded FIFO

This breakout board makes it easy to use the tiny MMA8452Q accelerometer in your project. The MMA8452Q is a smart low-power, three-axis, capacitive MEMS accelerometer with 12 bits of resolution. This accelerometer is packed with embedded functions with flexible user programmable options, configurable to two interrupt pins. Embedded interrupt functions allow for overall power savings relieving the host processor from continuously polling data.

The MMA8452Q has user selectable full scales of ±2g/±4g/±8g with high pass filtered data as well as non filtered data available real-time. The device can be configured to generate inertial wake-up interrupt signals from any combination of the configurable embedded functions allowing the MMA8452Q to monitor events and remain in a low power mode during periods of inactivity.

This board breaks out the ground, power, I2C and two external interrupt pins.

Note: If you are looking for the SparkFun Triple Axis Accelerometer Breakout with headers, it can be found here or in the Recommended Products below.

Get Started with the MMA8452Q Breakout Hookup Guide

Features

1.95 V to 3.6 V supply voltage

1.6 V to 3.6 V interface voltage

±2g/±4g/±8g dynamically selectable full-scale

Output Data Rates (ODR) from 1.56 Hz to 800 Hz

12-bit and 8-bit digital output

I2C digital output interface (operates to 2.25 MHz with 4.7 kΩ pullup)

Two programmable interrupt pins for six interrupt sources

Three embedded channels of motion detection

Orientation (Portrait/Landscape) detection with set hysteresis

High Pass Filter Data available real-time

Current Consumption: 6 μA – 165 μA

Because the Arduino (and Basic Stamp) are 5V devices, and most modern sensors, displays, flash cards and modes are 3.3V-only, many makers find that they need to perform level shifting/conversion to protect the 3.3V device from 5V.Although one can use resistors to make a divider, for high speed transfers, the resistors can add a lot of slew and cause havoc that is tough to debug. For that reason, we like using 4050/74LVX245 series and similar logic to perform proper level shifting. Only problem is that they are only good in one direction which can be a problem for some specialty bi-diectional interfaces and also makes wiring a little hairy.That's where this lovely chip, the TXB0108 bi-directional level converter comes in! This chip perform bidirectional level shifting from pretty much any voltage to any voltage and will auto-detect the direction. Only thing that doesn't work well with this chip is i2c (because it uses strong pullups which confuse auto-direction sensor). If you need to use pullups, you can but they should be at least 50K ohm - the ones internal to AVRs/Arduino are about 100K ohm so those are OK! Its a little more luxurious than a 74LVX245 but if you just don't want to worry about directional pins this is a life saver!Since this chip is a special bi-directional level shifter it does not have strong output pins that can drive LEDs or long cables, it's meant to sit on a breadboard between two logic chips! If you do not need instant bi-directional support, we suggest the 74LVX245 as below which has strong output drive.This breakout saves you from having to solder the very fine pitch packages that this chip comes with. We also add 0.1uF caps onto both sides and a 10K pull-up resistor on the output enable pin so you can use it right out of the box!

This tiny logic level shifter features four bi-directional channels, allowing for safe and easy communication between devices operating at different logic levels. It can convert signals as low as 1.5 V to as high as 18 V and vice versa, and its four channels are enough to support most common bidirectional and unidirectional digital interfaces, including I²C, SPI, and asynchronous TTL serial.

As digital devices get smaller and faster, once ubiquitous 5 V logic has given way to ever lower-voltage standards like 3.3 V, 2.5 V, and even 1.8 V, leading to an ecosystem of components that need a little help talking to each other. For example, a 5 V part might fail to read a 3.3 V signal as high, and a 3.3 V part might be damaged by a 5 V signal. This level shifter solves these problems by offering bidirectional voltage translation of up to four independent signals, converting between logic levels as low as 1.5 V on the lower-voltage side and as high as 18 V on the higher-voltage side, and its compact size and breadboard-compatible pin spacing make it easy to integrate into projects.

The logic high levels on each side of the shifter are achieved by 10 kΩ pull-up resistors to their respective supplies; these provide quick enough rise times to allow decent conversion of fast mode (400 kHz) I²C signals or other similarly fast digital interfaces (e.g. SPI or asynchronous TTL serial). External pull-ups can be added to speed up the rise time further at the expense of higher current draw. See the schematic diagram below for more information.

Dual-supply bus translation:

Lower-voltage (LV) supply can be 1.5 V to 7 V

Higher-voltage (HV) supply can be LV to 18 V

Lower-voltage (LV) supply can be 1.5 V to 7 V

Higher-voltage (HV) supply can be LV to 18 V

Four bidirectional channels

Small size: 0.4″ × 0.5″ × 0.08″ (13 mm × 10 mm × 2 mm)

Breadboard-compatible pin spacing

Example wiring diagram for connecting 5 V and 3.3 V devices through the 4-channel bidirectional logic level shifter.

This logic level converter requires two supply voltages: the lower-voltage logic supply (1.5 V to 7 V) connects to the LV pin and the higher-voltage supply (LV to 18 V) connects to the HV pin. The HV supply must be higher than the LV supply for proper operation. Logic low voltages will pass directly from Hx to the corresponding Lx (and vice versa), while logic high voltages will be converted between the HV level to the LV level as the signal passes from Hx to Lx or Lx to Hx.

The level shifter circuit does not require a ground connection to either device, so there are no ground pins on the board. (Some competing level shifter modules provide ground connections that simply act as a pass-through; we have opted to leave these off and make the board smaller.) The two devices being connected through the level shifter must still share a common ground.

The picture below shows a level-shifted TTL serial connection (RX and TX) between a 5 V Arduino Uno and a 3.3 V Raspberry Pi.

Using the 4-channel bidirectional logic level shifter to create a serial connection between a 5 V Arduino Uno and a 3.3 V Raspberry Pi.

A 0.1″-pitch male header strip is included for use with this board. The strip can be broken into smaller pieces and soldered in so the board can be used with perfboards, breadboards, or 0.1″ female connectors. Alternatively, wires can be soldered directly to the board for more compact installations. The connections are labeled on the back side of the of the PCB, so you might find it more convenient to solder the pins in the way that allows the labeled side to be facing up.

Schematic diagram

The logic level conversion is accomplished with a simple circuit consisting of a single n-channel MOSFET and a pair of 10 kΩ pull-up resistors for each channel. When Lx is driven low, the MOSFET turns on and the zero passes through to Hx. When Hx is driven low, Lx is also driven low through the MOSFET’s body diode, at which point the MOSFET turns on. In all other cases, both Lx and Hx are pulled high to their respective logic supply voltages. External pull-ups can be added to speed up the rise time. This same circuit is detailed in NXP’s application note on I²C bus level-shifting techniques, and we have used it before on carrier boards for 3.3 V sensors with I²C interfaces – like the MinIMU-9 – to enable them to work directly with both 3.3 V and 5 V systems.

This schematic is also available as a downloadable PDF (135k pdf).

People often buy this product together with:

If you’ve ever tried to connect a 3.3V device to a 5V system, you know what a challenge it can be. The SparkFun bi-directional logic level converter is a small device that safely steps down 5V signals to 3.3V AND steps up 3.3V to 5V at the same time. This level converter also works with 2.8V and 1.8V devices. What really separates this Logic level converter from our previous versions is that you can successfully set your high and low voltages and step up and down between them safely on the same channel. Each level converter has the capability of converting 4 pins on the high side to 4 pins on the low side with two inputs and two outputs provided for each side.

The level converter is very easy to use. The board needs to be powered from the two voltages sources (high voltage and low voltage) that your system is using. High voltage (5V for example) to the ‘HV’ pin, low voltage (3.3V for example) to ‘LV’, and ground from the system to the ‘GND’ pin.

Get Started with the Logic Level Converter Guide

Features

0.63 x 0.52" (16.05 x 13.33mm)

Give your next sensor project a nose for gasses with the Adafruit MiCS-5524 Gas Sensor Breakout. This breakout makes it easy to use this nice sensor from SGX Sensortech. The MiCS-5524 is a robust MEMS sensor for indoor carbon monoxide and natural gas leakage detection, it's suitable also for indoor air quality monitoring; breath checker and early fire detection.

Please note: This sensor is sensitive to CO ( ~ 1 to 1000 ppm), Ammonia (~ 1 to 500 ppm), Ethanol (~ 10 to 500 ppm), H2 (~ 1 - 1000 ppm), and Methane / Propane / Iso-Butane (~ 1,000++ ppm). However, it can't tell you which gas it has detected. 

This breakout board is not for any safety, medical or finished product usage. We're selling it for hobby education & experimentation and don't guarantee it for any other purpose! All gas sensors require calibration for precision output.

Using it is easy: Power it with 5 VDC and read the analog voltage off of the output pin. When gasses are detected, the analog voltage will increase in proportion of detected gas. When powered, the heater draws about 25-35mA. You can use the EN pin to power it off (pull it high to 5V to turn off) to conserve energy. Just make sure to wait a second after turning the heater on to make sure its all heated before taking readings.

Each order comes with one assembled and tested MiCS-5524 breakout and a bit of header. You'll need to do some light soldering to attach the header on - or you can use just plain wires.

Check out the tutorial for files, example code, diagrams and more!

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).

Upgrade a project that uses a photocell with the GA1A12S202 analog light sensor. Like a CdS photo-cell, the sensor does not require a microcontroller, the analog voltage output increases with the amount of light shining on the sensor face. This sensor has a lot of improvements that make it better for nearly any project.The biggest improvement over plain photocells is a true log-lin relationship with light levels. Most light sensors have a linear relationship with light levels, which means that they're not very sensitive to changes in darkened areas and 'max' out very easily when there's a lot of light. Sometimes you can tweak a resistor to make them better in dark or bright light but its hard to get good performance at both ends. This sensor is logarithmic over a large dynamic range of 3 to 55,000 Lux, so it has a lot of sensitivity at low light levels but is also nearly impossible to "max out" so you can use it indoors or outdoors without changing code or calibration. Since the sensor is fabricated on a chip, there are also fewer manufacturing variations, so you won't have to calibrate the sensor from one board to another.Using the sensor is easy as pie: connect the Vin to 2.3-6VDC, Gnd to ground and measure the analog output on OUT. It will range up to 3V (at extremely bright outdoor sunlight). On an Arduino, just use analogRead() with the OUT pin connected to an analog pin. For more information including graphs, power consumption, etc check out the datasheet in the Tech Details tab. On this breakout we placed a 68KΩ resistor from OUT to ground to turn the current into a voltage.

GA1A12S202 Log-scale Analog Light Sensor (6:52)

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:

Basic breakout board for the TEMT6000 Ambient Light Sensor. Only what you need, nothing you don’t. Sensor acts like a transistor - the greater the incoming light, the higher the analog voltage on the signal pin.

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:

Electronics and water don't usually mix - which is why liquid level sensing projects can be a little challenging. You can DIY a sensor but keeping it clean and un-oxidized can be a pain. The Optomax Digital liquid level switches are a clever solution for when you need a small sensor to detect liquid/water: super easy to use and very durable too!

Inside the plastic sensor casing is an infrared (IR) LED and matching photo transistor. When in the open air, the IR light bounces back to the sensor so you know its nice and dry. When the sensing tip is immersed in liquid, the IR light escapes, and the transistor turns off. The sensor can detect the presence or absence of almost any liquid type; oil or water based. It is insensitive to ambient light and is not affected by foam when in air or by small bubbles when in liquid.

The microcontroller-friendly logic level output is push-pull type, and can sink and source up to 100mA at a supply voltage range of 4.5 to 15.4VDC - so you can even use it to directly control a transistor or perhaps even a small relay.

Simply connect the Blue/Black wire to ground, the Red wire to 4.5-15.4VDC and look at the output with your multimeter or microcontroller. When dry the output is the same as the red wire. When wet, the output is 0V. Note they're pretty sensitive, any liquid on the sensor (e.g. droplets on the surface) can trigger it.

Comes in a chemically resistant Polysulfone housing material – the standard choice for most applications – for external sensor mounting and for use in standard operating temperature ranges (-25 to 80°C).

Features:

Reverse polarity, ESD and transient over-voltage protected

Wide supply voltage range

Push-pull output, capable of sinking or sourcing up to 100mA, can directly drive small loads

Solid state, fully enclosed, so no moving parts to cause unreliability

Small in size so they can be installed in applications where space is limited

Can detect tiny amounts of liquid when positioned correctly, ideal for leak detection

Fast response time

Repeatable switching point

Built-in output delays available on request for applications where sloshing causes intermittent switching

Very robust permitting use in a wide range of fluids and chemicals

See datasheet in Technical Details for more specs and info! 

These are massive single pole - double throw (SPDT) sealed relays. This means that when current is applied to the coil it throws a simple changeover switch, terminating the connection from the NC contact to ground and closing the NO contact. Use them to switch high voltage/high current devices.

Features

SPDT Relay

Contacts Rated up to 220VAC @ 20A

Coil Voltage: 5V

Fully Sealed

This soft potentiometer is an interesting way to add an adjustable resistor / slide potentiometer to your wearable. You can use it to adjust the brightness of an LED, or as a sensor input to your Flora or Gemma. When the ring slides up and down the ribbon, the resistance from the end of the ribbon to ring will vary from ~100 ohms to about 8Kohm.

To use as a voltage-output potentiometer, connect one end to ground and the other end to 3.3V or so, then measure the voltage on the ring in reference to ground. For an adjustable resistor, connect to one end of the ribbon and the ring, let the other end  hang disconnected.

The kit includes 50cm of specially-woven conductive ribbon and a stainless steel metal ring.

This sensor is a carrier/breakout board for ST’s VL53L0X laser-ranging sensor, which measures the range to a target object up to 2 m away. The VL53L0X uses time-of-flight measurements of infrared pulses for ranging, allowing it to give accurate results independent of the target’s color and surface. Distance measurements can be read through a digital I²C interface. The board has a 2.8 V linear regulator and integrated level-shifters that allow it to work over an input voltage range of 2.6 V to 5.5 V, and the 0.1″ pin spacing makes it easy to use with standard solderless breadboards and 0.1″ perfboards.

The VL53L0X from ST Microelectronics is a time-of-flight ranging system integrated into a compact module. This board is a carrier for the VL53L0X, so we recommend careful reading of the VL53L0X datasheet (1MB pdf) before using this product.

The VL53L0 uses ST’s FlightSense technology to precisely measure how long it takes for emitted pulses of infrared laser light to reach the nearest object and be reflected back to a detector, so it can be considered a tiny, self-contained lidar system. This time-of-flight (TOF) measurement enables it to accurately determine the absolute distance to a target without the object’s reflectance greatly influencing the measurement. The sensor can report distances of up to 2 m (6.6 ft) with 1 mm resolution, but its effective range and accuracy (noise) depend heavily on ambient conditions and target characteristics like reflectance and size, as well as the sensor configuration. (The sensor’s accuracy is specified to range from ±3% at best to over ±10% in less optimal conditions.)

Ranging measurements are available through the sensor’s I²C (TWI) interface, which is also used to configure sensor settings, and the sensor provides two additional pins: a shutdown input and an interrupt output.

The VL53L0X is a great IC, but its small, leadless, LGA package makes it difficult for the typical student or hobbyist to use. It also operates at a recommended voltage of 2.8 V, which can make interfacing difficult for microcontrollers operating at 3.3 V or 5 V. Our breakout board addresses these issues, making it easier to get started using the sensor, while keeping the overall size as small as possible.

The carrier board includes a low-dropout linear voltage regulator that provides the 2.8 V required by the VL53L0X, which allows the sensor to be powered from a 2.6 V to 5.5 V supply. The regulator output is available on the VDD pin and can supply almost 150 mA to external devices. The breakout board also includes a circuit that shifts the I²C clock and data lines to the same logic voltage level as the supplied VIN, making it simple to interface the board with 3.3 V or 5 V systems, and the board’s 0.1″ pin spacing makes it easy to use with standard solderless breadboards and 0.1″ perfboards. The board ships fully populated with its SMD components, including the VL53L0X, as shown in the product picture.

For for similar alternatives to this sensor, see our shorter-range 60 cm VL6180X carrier and longer-range 400 cm VL53L1X carrier. Both of these are physical drop-in replacements for the VL53L0X carrier, but they have different APIs, so software for the VL53L0X will need to be rewritten to work with the VL6180X or VL53L1X.

VL53L0X datasheet graph of typical ranging performance (in default mode).

Specifications

Dimensions: 0.5″ × 0.7″ × 0.085″ (13 mm × 18 mm × 2 mm)

Weight without header pins: 0.5 g (0.02 oz)

Operating voltage: 2.6 V to 5.5 V

Supply current: 10 mA (typical average during active ranging)

Varies with configuration, target, and environment. Peak current can reach 40 mA.

Varies with configuration, target, and environment. Peak current can reach 40 mA.

Output format (I²C): 16-bit distance reading (in millimeters)

Distance measuring range: up to 2 m (6.6 ft); see the graph at the right for typical ranging performance.

Effective range depends on configuration, target, and environment.

The datasheet does not specify a minimum range, but in our experience, the effective limit is about 3 cm.

Effective range depends on configuration, target, and environment.

The datasheet does not specify a minimum range, but in our experience, the effective limit is about 3 cm.

Included components

A 1×7 strip of 0.1″ header pins and a 1×7 strip of 0.1″ right-angle header pins are included, as shown in the picture below. You can solder the header strip of your choice to the board for use with custom cables or solderless breadboards, or you can solder wires directly to the board itself for more compact installations.

VL53L0X Time-of-Flight Distance Sensor Carrier with included header pins.

VL53L0X Time-of-Flight Distance Sensor Carrier in a breadboard.

The board has two mounting holes spaced 0.5″ apart that work with #2 and M2 screws (not included).

Important note: This product might ship with a protective liner covering the sensor IC. The liner must be removed for proper sensing performance.

Connections

At least four connections are necessary to use the VL53L0X board: VIN, GND, SCL, and SDA. The VIN pin should be connected to a 2.6 V to 5.5 V source, and GND should be connected to 0 volts. An on-board linear voltage regulator converts VIN to a 2.8 V supply for the VL53L0X IC.

The I²C pins, SCL and SDA, are connected to built-in level-shifters that make them safe to use at voltages over 2.8 V; they should be connected to an I²C bus operating at the same logic level as VIN.

The XSHUT pin is an input and the GPIO1 pin is an open-drain output; both pins are pulled up to 2.8 V by the board. They are not connected to level-shifters on the board and are not 5V-tolerant, but they are usable as-is with many 3.3 V and 5 V microcontrollers: the microcontroller can read the GPIO1 output as long as its logic high threshold is below 2.8 V, and the microcontroller can alternate its own output between low and high-impedance states to drive the XSHUT pin. Alternatively, our 4-channel bidirectional logic level shifter can be used externally with those pins.

Pinout

Schematic diagram

The above schematic shows the additional components the carrier board incorporates to make the VL53L0 easier to use, including the voltage regulator that allows the board to be powered from a 2.6 V to 5.5 V supply and the level-shifter circuit that allows for I²C communication at the same logic voltage level as VIN. This schematic is also available as a downloadable PDF (110k pdf).

I²C communication

The VL53L0X can be configured and its distance readings can be queried through the I²C bus. Level shifters on the I²C clock (SCL) and data (SDA) lines enable I²C communication with microcontrollers operating at the same voltage as VIN (2.6 V to 5.5 V). A detailed explanation of the I²C interface on the VL53L0X can be found in its datasheet (1MB pdf), and more detailed information about I²C in general can be found in NXP’s I²C-bus specification (1MB pdf).

The sensor’s 7-bit slave address defaults to 0101001b on power-up. It can be changed to any other value by writing one of the device configuration registers, but the new address only applies until the sensor is reset or powered off. ST provides an application note (196k pdf) that describes how to use multiple VL53L0X sensors on the same I²C bus by individually bringing each sensor out of reset and assigning it a unique address.

The I²C interface on the VL53L0X is compliant with the I²C fast mode (400 kHz) standard. In our tests of the board, we were able to communicate with the chip at clock frequencies up to 400 kHz; higher frequencies might work but were not tested.

Sensor configuration and control

In contrast with the information available for many other devices, ST has not publicly released a register map and descriptions or other documentation about configuring and controlling the VL53L0X. Instead, communication with the sensor is intended to be done through ST’s VL53L0X API (STSW-IMG005), a set of C functions that take care of the low-level interfacing. To use the VL53L0X, you can customize the API to run on a host platform of your choice using the information in the API documentation. Alternatively, it is possible to use the API source code as a guide for your own implementation.

Sample Code

We have written a basic Arduino library for the VL53L0X, which can be used as an alternative to ST’s official API for interfacing this sensor with an Arduino or Arduino-compatible controller. The library makes it simple to configure the VL53L0X and read the distance data through I²C. It also includes example sketches that show you how to use the library.

People often buy this product together with:

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.

This sensor is a carrier/breakout board for ST’s VL6180X proximity and ambient light sensor, which measures the range to a target object up to 20 cm away (or 60 cm with reduced resolution). The VL6180X uses time-of-flight measurements of infrared pulses for ranging, allowing it to give accurate results independent of the target’s color and surface. Distance and ambient light level measurements can be read through a digital I²C interface. The board has a 2.8 V linear regulator and integrated level-shifters that allow it to work over an input voltage range of 2.7 V to 5.5 V, and the 0.1″ pin spacing makes it easy to use with standard solderless breadboards and 0.1″ perfboards.

The VL6180X from ST Microelectronics is a sensor that combines proximity ranging and ambient light level measurement capabilities into a single package. This board is a carrier for the VL6180X, so we recommend careful reading of the VL6180X datasheet (2MB pdf) before using this product.

Unlike simpler optical sensors that use the intensity of reflected light to detect objects, the VL6180 uses ST’s FlightSense technology to precisely measure how long it takes for emitted pulses of infrared laser light to reach the nearest object and be reflected back to a detector, making it essentially a short-range lidar sensor. This time-of-flight (TOF) measurement enables it to accurately determine the absolute distance to a target with 1 mm resolution, without the object’s reflectance influencing the measurement. The sensor is rated to perform ranging measurements of up to 10 cm (4″), but it can often provide readings up to 20 cm (8″) with its default settings. Furthermore, the VL6180X can be configured to measure ranges of up to 60 cm (24″) at the cost of reduced resolution, although successful ranging at these longer distances will depend heavily on the target and environment. (For more information, see “Range scaling factor” below.)

The VL6180 also includes an ambient light sensor, or ALS, that can measure the intensity of light with which it is illuminated. Ranging and ambient light measurements are available through the sensor’s I²C (TWI) interface, which is also used to configure sensor settings, and two independently-programmable GPIO pins can be configured as interrupt outputs.

The VL6180X is a great IC, but its small, leadless, LGA package makes it difficult for the typical student or hobbyist to use. It also operates at voltages below 3 V, which can make interfacing difficult for microcontrollers operating at 3.3 V or 5 V. Our breakout board addresses these issues, making it easier to get started using the sensor, while keeping the overall size as small as possible.

The carrier board includes a low-dropout linear voltage regulator that provides the 2.8 V required by the VL6180X, which allows the sensor to be powered from a 2.7 V to 5.5 V supply. The regulator output is available on the VDD pin and can supply almost 150 mA to external devices. The breakout board also includes a circuit that shifts the I²C clock and data lines to the same logic voltage level as the supplied VIN, making it simple to interface the board with 3.3 V or 5 V systems, and the board’s 0.1″ pin spacing makes it easy to use with standard solderless breadboards and 0.1″ perfboards. The board ships fully populated with its SMD components, including the VL6180X, as shown in the product picture.

For for similar, longer-range sensors, see our 200 cm VL53L0X carrier and 400 cm VL53L1X carrier. Both of these are physical drop-in replacements for the VL6180X carrier, but they have different APIs, so software for the VL6180X will need to be rewritten to work with the VL53L0X or VL53L1X.

VL6180X datasheet graph of typical ranging performance.

Specifications

Dimensions: 0.5″ × 0.7″ × 0.085″ (13 mm × 18 mm × 2 mm)

Weight without header pins: 0.5 g (0.02 oz)

Operating voltage: 2.7 V to 5.5 V

Supply current: 5 mA (typical; varies with configuration, target, and environment)

Output format (I²C): 8-bit distance reading (in millimeters), 16-bit ambient light reading

Distance measuring range: up to 10 cm (4″) specified; up to 60 cm (24″) possible with reduced resolution. See the graph at the right for typical ranging performance.

Ranging beyond 10 cm is possible with certain target reflectances and ambient conditions but not guaranteed by specifications. By default, the sensor can report distances up to 20 cm, or it can be configured to measure up to 60 cm with reduced resolution.

The datasheet does not specify a minimum range, but in our experience, the effective limit is about 1 cm.

Ranging beyond 10 cm is possible with certain target reflectances and ambient conditions but not guaranteed by specifications. By default, the sensor can report distances up to 20 cm, or it can be configured to measure up to 60 cm with reduced resolution.

The datasheet does not specify a minimum range, but in our experience, the effective limit is about 1 cm.

Included components

A 1×7 strip of 0.1″ header pins and a 1×7 strip of 0.1″ right-angle header pins are included, as shown in the picture below. You can solder the header strip of your choice to the board for use with custom cables or solderless breadboards, or you can solder wires directly to the board itself for more compact installations.

VL6180X Time-of-Flight Distance Sensor Carrier with included header pins.

VL6180X Time-of-Flight Distance Sensor Carrier in a breadboard.

The board has two mounting holes spaced 0.5″ apart that work with #2 and M2 screws (not included).

Connections

At least four connections are necessary to use the VL6180X board: VIN, GND, SCL, and SDA. The VIN pin should be connected to a 2.7 V to 5.5 V source, and GND should be connected to 0 volts. An on-board linear voltage regulator converts VIN to a 2.8 V supply for the VL6180X IC.

The I²C pins, SCL and SDA, are connected to built-in level-shifters that make them safe to use at voltages over 2.8 V; they should be connected to an I²C bus operating at the same logic level as VIN.

The two GPIO pins are open-drain outputs pulled up to 2.8 V by the board (although GPIO0 defaults to being a chip enable input). They are not connected to level-shifters on the board and are not 5V-tolerant, but they are usable as-is with many 3.3 V and 5 V microcontrollers: the microcontroller can read the sensor’s output as long as its logic high threshold is below 2.8 V, and the microcontroller can alternate its own output between low and high-impedance states to drive the pin. Alternatively, our 4-channel bidirectional logic level shifter can be used externally with those pins.

Pinout

Schematic diagram

The above schematic shows the additional components the carrier board incorporates to make the VL6180 easier to use, including the voltage regulator that allows the board to be powered from a 2.7 V to 5.5 V supply and the level-shifter circuit that allows for I²C communication at the same logic voltage level as VIN. This schematic is also available as a downloadable PDF (90k pdf).

I²C communication

The VL6180X can be configured and its distance and ambient light readings can be queried through the I²C bus. Level shifters on the I²C clock (SCL) and data (SDA) lines enable I²C communication with microcontrollers operating at the same voltage as VIN (2.7 V to 5.5 V). A detailed explanation of the I²C interface on the VL6180X can be found in its datasheet (2MB pdf), and more detailed information about I²C in general can be found in NXP’s I²C-bus specification (1MB pdf).

The sensor’s 7-bit slave address defaults to 0101001b on power-up. It can be changed to any other value by writing one of the device configuration registers, but the new address only applies until the sensor is reset or powered off.

The I²C interface on the VL6180X is compliant with the I²C fast mode (400 kHz) standard. In our tests of the board, we were able to communicate with the chip at clock frequencies up to 400 kHz; higher frequencies might work but were not tested.

Sample Code

We have written a basic Arduino library for the VL6180X that makes it easy to interface this sensor with an Arduino or Arduino-compatible controller. The library makes it simple to configure the VL6180X and read the distance and ambient light level data through I²C. It also includes example sketches that show you how to use the library.

Protocol hints

The datasheet provides a lot of information about this sensor, but a lot of essential info – including a mandatory initialization sequence – can only be found in other documents. Picking out the important details can take some time. Here are some pointers for communicating with and configuring the VL6180X that we hope will get you up and running a little bit faster:

Unlike many other I²C sensors from ST, which use 8-bit register addresses, the VL6180X uses 16-bit register addresses.

The sensor must be initialized with a particular sequence of settings on power-up or reset. This sequence is not covered in the datasheet, but it can be found in ST application note AN4545 (706k pdf) and design tip DT0037 (386k pdf). (Our Arduino library includes a function that performs this initialization.)

The two documents above can also help you understand basic procedures for configuring the VL6180X and getting readings from it. Additional documents, providing details on many other aspects of the VL6180X, can be found on ST’s product page for the VL6180X.

Both distance and ambient light measurements can be performed in either single-shot or continuous mode. In either mode, once each measurement is started, you must poll a status register to wait for it to complete. In continuous mode, you should ensure that the inter-measurement period you select is longer than the time it takes to actually perform each measurement.

Range scaling factor

Although the VL6180X specifications state a maximum “guaranteed” range of 10 cm, the sensor can report distances of up to 20 cm with its default settings. By configuring a range scaling factor, the potential maximum range of the sensor can be increased at the cost of lower resolution. Setting the scaling factor to 2 provides up to 40 cm range with 2 mm resolution, while a scaling factor of 3 provides up to 60 cm range with 3 mm resolution. In all cases, the reading is given as a number between 0 and 200; with the default 1× scaling, this corresponds directly to a distance in mm, but with 2× or 3× scaling, the raw reading will represent a measurement in units of 2 mm or 3 mm, respectively (so the reading should be multiplied by 2 or 3 to obtain a result in millimeters).

Range scaling is not mentioned in the VL6180X datasheet as of Rev 7, but it is available in the VL6180X API provided by ST (STSW-IMG003). Our Arduino library also provides functions to set the range scaling factor.

People often buy this product together with:

This sensor is a carrier/breakout board for ST’s VL53L1X laser-ranging sensor, which offers fast and accurate ranging up to 4 m. It uses the time of flight (ToF) of invisible, eye-safe laser pulses to measure absolute distances independent of ambient lighting conditions and target characteristics like color, shape, and texture (though these things will affect the maximum range). The VL53L1X also features a programmable region of interest (ROI), so the full field of view can be reduced or divided into multiple zones. Distance measurements can be read through a digital I²C interface. The board includes a 2.8 V linear regulator and level-shifters that allow it to work over an input voltage range of 2.6 V to 5.5 V, and the 0.1″ pin spacing makes it easy to use with standard solderless breadboards and 0.1″ perfboards.

The VL53L1X from ST Microelectronics is a long-distance ranging time-of-flight (TOF) sensor integrated into a compact module. This board is a carrier for the VL53L1X, so we recommend careful reading of the VL53L1X datasheet (1MB pdf) before using this product.

The VL53L1X is effectively a tiny, self-contained lidar system featuring an integrated 940 nm Class 1 laser, which is invisible and eye-safe. Unlike conventional IR sensors that use the intensity of reflected light to estimate the distance to an object, the VL53L1X uses ST’s FlightSense technology to precisely measure how long it takes for emitted pulses of infrared laser light to reach the nearest object and be reflected back to a detector. This approach ensures absolute distance measurements independent of ambient lighting conditions and target characteristics (e.g. color, shape, texture, and reflectivity), though these external conditions do affect the maximum range of the sensor, as do the sensor configuration settings.

Under favorable conditions, such as low ambient light with a high-reflectivity target, the sensor can report distances up to 4 m (13 ft) with 1 mm resolution. See the datasheet for more information on how various external conditions and sensor configurations affect things like maximum range, repeatability, and ranging error. The minimum ranging distance is 4 cm; inside of this range, the sensor will still detect a target, but the measurement will not be accurate. Ranging measurements are available through the sensor’s I²C (TWI) interface, which is also used to configure sensor settings, and the sensor provides two additional pins: a shutdown input and an interrupt output.

The VL53L1X offers three distance modes: short, medium, and long. Long distance mode allows the longest possible ranging distance of 4 m, but the maximum range is significantly affected by ambient light. Short distance mode is mostly immune to ambient light, but the maximum ranging distance is typically limited to 1.3 m (4.4 ft). The maximum sampling rate in short distance mode is 50 Hz while the maximum sampling rate for medium and long distance modes is 30 Hz. Performance can be improved in all modes by using lower sampling rates and longer timing budgets (as can be seen in the figure above).

For advanced applications, the VL53L1X supports configurable thresholds that can be used to trigger interrupts when a target is detected below a certain distance, beyond a certain distance, outside of a range, or within a range. It also supports an alternate detection mode that generates an interrupt when no target is present. Additionally, unlike its predecessors, the VL53L1X supports a configurable region of interest (ROI) within its full 16×16 sensing array, allowing you to reduce the field of view (FoV). With all 265 detection elements enabled, the FoV is 27°. An “Autonomous Low Power” mode that is specially tuned for advanced presence detection is available. This mode allows for significant system power saving by switching off or waking up the host automatically when a human or object is detected within the configured distance thresholds in the region of interest.

The VL53L1X is a great IC, but its small, leadless, LGA package makes it difficult for the typical student or hobbyist to use. It also operates at a recommended voltage of 2.8 V, which can make interfacing difficult for microcontrollers operating at 3.3 V or 5 V. Our breakout board addresses these issues, making it easier to get started using the sensor, while keeping the overall size as small as possible.

The carrier board includes a low-dropout linear voltage regulator that provides the 2.8 V required by the VL53L1X and allows the sensor to be powered from a 2.6 V to 5.5 V supply. The regulator output is available on the VDD pin and can supply almost 150 mA to external devices. The breakout board also includes a circuit that shifts the I²C clock and data lines to the same logic voltage level as the supplied VIN, making it simple to interface the board with 3.3 V or 5 V systems, and the board’s 0.1″ pin spacing makes it easy to use with standard solderless breadboards and 0.1″ perfboards. The board ships fully populated with its SMD components, including the VL53L1X, as shown in the product picture.

For for similar but shorter-range sensors, see our 200 cm VL53L0X carrier and 60 cm VL6180X carrier. Both of these are physical drop-in replacements for the VL53L1X carrier, but they have different APIs, so software for the VL53L1X will need to be rewritten to work with the VL53L0X or VL6180X.

Features and specifications

Dimensions: 0.5″ × 0.7″ × 0.085″ (13 mm × 18 mm × 2 mm)

Weight without header pins: 0.5 g (0.02 oz)

Operating voltage: 2.6 V to 5.5 V

Supply current: ~15 mA (typical average during active ranging at max sampling rate)

Varies with configuration, target, and environment; peak current can reach 40 mA

Varies with configuration, target, and environment; peak current can reach 40 mA

Fast and accurate ranging with three distance mode options:

Short: up to ~130 cm, 50 Hz max sampling rate; this mode is the most immune to interference from ambient light

Medium: up to ~300 cm in the dark, 30 Hz max sampling rate

Long: up to 400 cm in the dark, 30 Hz max sampling rate

Short: up to ~130 cm, 50 Hz max sampling rate; this mode is the most immune to interference from ambient light

Medium: up to ~300 cm in the dark, 30 Hz max sampling rate

Long: up to 400 cm in the dark, 30 Hz max sampling rate

Minimum range: 4 cm (objects under this range are detected, but measurements are not accurate)

Emitter: 940 nm invisible Class 1 VCSEL (vertical cavity surface-emitting laser) – eye-safe

Detector: 16×16 SPAD (single photon avalanche diode) receiving array with integrated lens

Typical full field of view (FoV): 27°

Programmable region of interest (ROI) size on the receiving array, allowing the sensor FoV to be reduced

Programmable ROI position on the receiving array, allowing multizone operation control from the host

Typical full field of view (FoV): 27°

Programmable region of interest (ROI) size on the receiving array, allowing the sensor FoV to be reduced

Programmable ROI position on the receiving array, allowing multizone operation control from the host

Configurable detection interrupt thresholds for implementing autonomous low-power presence detection:

target closer than threshold

target farther than threshold

target within distance window

target outside of distance window

no target

target closer than threshold

target farther than threshold

target within distance window

target outside of distance window

no target

Output format (I²C): 16-bit distance reading (in millimeters)

Included components

A 1×7 strip of 0.1″ header pins and a 1×7 strip of 0.1″ right-angle header pins are included, as shown in the picture below. You can solder the header strip of your choice to the board for use with custom cables or solderless breadboards, or you can solder wires directly to the board itself for more compact installations.

VL53L1X Time-of-Flight Distance Sensor Carrier with included header pins.

VL53L1X Time-of-Flight Distance Sensor Carrier in a breadboard.

The board has two mounting holes spaced 0.5″ apart that work with #2 and M2 screws (not included).

Important note: This product might ship with a protective liner covering the sensor IC. The liner must be removed for proper sensing performance.

Connections

At least four connections are necessary to use the VL53L1X board: VIN, GND, SCL, and SDA. The VIN pin should be connected to a 2.6 V to 5.5 V source, and GND should be connected to 0 volts. An on-board linear voltage regulator converts VIN to a 2.8 V supply for the VL53L1X IC. Note that if your input voltage is under 3.5 V, you can connect it directly to VDD instead to bypass the regulator; in this configuration, VIN should remain disconnected.

The I²C pins, SCL and SDA, are connected to built-in level-shifters that make them safe to use at voltages over 2.8 V; they should be connected to an I²C bus operating at the same logic level as VIN.

The XSHUT pin is an input and the GPIO1 pin is an open-drain output; both pins are pulled up to 2.8 V by the board. They are not connected to level-shifters on the board and are not 5V-tolerant, but they are usable as-is with many 3.3 V and 5 V microcontrollers: the microcontroller can read the GPIO1 output as long as its logic high threshold is below 2.8 V, and the microcontroller can alternate its own output between low and high-impedance states to drive the XSHUT pin. Alternatively, our 4-channel bidirectional logic level shifter can be used externally with those pins.

Pinout

Schematic diagram

The above schematic shows the additional components the carrier board incorporates to make the VL53L1 easier to use, including the voltage regulator that allows the board to be powered from a 2.6 V to 5.5 V supply and the level-shifter circuit that allows for I²C communication at the same logic voltage level as VIN. This schematic is also available as a downloadable PDF (110k pdf).

I²C communication

The VL53L1X can be configured and its distance readings can be queried through the I²C bus. Level shifters on the I²C clock (SCL) and data (SDA) lines enable I²C communication with microcontrollers operating at the same voltage as VIN (2.6 V to 5.5 V). A detailed explanation of the I²C interface on the VL53L1X can be found in its datasheet (1MB pdf), and more detailed information about I²C in general can be found in NXP’s I²C-bus specification (1MB pdf).

The sensor’s 7-bit slave address defaults to 0101001b on power-up. It can be changed to any other value by writing one of the device configuration registers, but the new address only applies until the sensor is reset or powered off. ST provides an application note (196k pdf) that describes how to use multiple VL53L0X sensors on the same I²C bus by individually bringing each sensor out of reset and assigning it a unique address, and the approach can be easily adapted to apply to the VL53L1X instead.

The I²C interface on the VL53L1X is compliant with the I²C fast mode (400 kHz) standard. In our tests of the board, we were able to communicate with the chip at clock frequencies up to 400 kHz; higher frequencies might work but were not tested.

Sensor configuration and control

In contrast with the information available for many other devices, ST has not publicly released a register map and descriptions or other documentation about configuring and controlling the VL53L1X. Instead, communication with the sensor is intended to be done through ST’s VL53L1X API (STSW-IMG007), a set of C functions that take care of the low-level interfacing. To use the VL53L1X, you can customize the API to run on a host platform of your choice using the information in the API documentation. Alternatively, it is possible to use the API source code as a guide for your own implementation.

Sample code

We have written a basic Arduino library for the VL53L1X, which can be used as an alternative to ST’s official API for interfacing this sensor with an Arduino or Arduino-compatible controller. The library makes it simple to configure the VL53L1X and read the distance data through I²C. It also includes example sketches that show you how to use the library.

We also have an implementation of ST’s VL53L1X API for Arduino available, including an example sketch. Compared to our library, the API has a more complicated interface and uses more storage and memory, but it offers some advanced functionality that our library does not provide and has more robust error checking. Consider using the API for advanced applications, especially when storage and memory are less of an issue.

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