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

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

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

Features

Extremely efficient class-D amplifier

1.4W into 8 Ohms

2.5V to 5.5V supply

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

Shutdown input with pullup and LED-follows-shutdown circuitry

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

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

This audio adapter lets you easily add high quality 16 bit, 44.1 kHz sample rate (CD quality) audio to your projects with a Teensy 3.2, 3.5 or 3.6. It supports stereo headphone and stereo line-level output, and also stereo line-level input or mono microphone input.The audio chip connects to Teensy v3 using 7 signals. The I2C pins SDA and SCL are used to control the chip and adjust parameters. Audio data uses I2S signals, TX (to headphones and/or line out) and RX (from line in or mic), and 3 clocks, LRCLK (44.1 kHz), BCLK (1.41 MHz) and MCLK (11.29 MHz). All 3 clocks are created by Teensy 3.1. The SGTL5000 chip operates in "slave mode", where all its clock pins are inputs.

As of February 23rd, 2015 we are shipping an updated version with a few minor changes.This product does NOT include a Teensy, it's just the audio adapter!