This audio utility board was designed by Arthur Sobel to facilitate the construction of simple audio devices, and is showcased on on Hackster.io.

On this board you will find a footprint for the Teensy 3.2 , a single channel PAM8302M speaker amp, MicroSD breakout board, and connectors for keyboard, switches and pots. It’s based on the NXP ARM Cortex M4 MK20DX256VLH7, which has AnalogIO with one DAC pin. It runs at 72Mhz, using a modified  MPR121 test library.