At first, it seemed like a laudable effort. I hate it, though, when someone makes a github repo and sticks a single zip file in it: https://github.com/bhamla-lab/LoCHAid-2020-PLOS-ONE

So I found the pdf in the zip file where you can see what it is. It's a MAX 98306 amp. The only peripherals are the typical filter capacitors, resistors, volume pot, microphone, etc. So, it's basically this: https://www.adafruit.com/product/987