Recently, I’ve ran across a lot of TDA7231 chips in my workshop and figured out I’d use them for something. That something turned out to be a stereo 1.6W audio amplifier, which I named the Matchbox Screamer. Here’s the circuit diagram:
The circuit is based on the example circuit in the datasheet and is designed to operate voltage-independent. The voltage range is 1.8-15 V, with which also varies the output power. That means it can be powered from basically whatever you desire, from li-ion batteries, to USB, to 9V batteries.
I still have to etch the PCB for the thing and will post an update when I build and test it.