Adafruit I2S Amplifier BFF Add-On for QT Py and Xiao

by Adafruit

QT Py/Xiao boards are a great way to make very small microcontroller projects that pack a ton of power - and now Adafruit have a way for you to add a I2S 3 Watt amplifier, for high quality audio playback, that can fit on the back of your miniature dev board. It uses just three GPIO pins that do not intersect with the I2C/UART or SPI port.

Adafruit call this the Adafruit I2S Amp BFF - a "Best Friend Forever". When you were a kid you may have learned about the "buddy" system, well this product is kinda like that! A board that will watch your QT Py's back and give it more capabilities.

This PCB is designed to fit onto the back of any QT Py or Xiao board, it can be soldered into place or use pin and socket headers to make it removable. Onboard is a MAX98357 audio amplifier and picoblade-compatible connector for plugigng in a 4 or 8 ohm speaker. We use A0 for the audio data, A1 for wordselect clock, and A2 for bitclock. This pinout will work with ESP32 series, nRF52840 and RP2040 chipset boards. It won't work with the ATSAMD21 'original 'QT Py because those pins on the SAMD21 are not I2S capable. However, you could cut and rewire the traces to connect to the I2S pads if desired - personally we recommend just upgrading to an RP2040 QT Py instead.

Adafruit include some header that you can solder to your QT Py. You can also pick up an Itsy Bitsy short female header kit to make it removable but compact, you'll just need to trim down the headers to 7 pins long.

Speaker and QT Py are not included.

Technical Details

RoHS 2 2011 65 EU CompliantRoHS 2 2015 863 EU Compliant