This project is a printed circuit board that's playable like a piano. Touching the exposed pads plays a note from the on-board speaker. It's still a work in process, but version two is on its way!
The most important choice in designing the PCB is picking the chip to be at it's heart. I chose the ESP32-S2. It's fast, inexpensive, and most importantly to this project, it has capactive touch sensing ability. This lets it detect when a piano key is pressed. I then picked "life-support" components for the chip and planned how they'd all be wired together by making the schematic pictured above.
Unfortunately, I mistakenly picked a version of the ESP32 without built-in SRAM, breaking the whole device. A new version is on order (September 2022) and it should be fixed soon. Engineering is iterative!
The final design step is to route the wires (called traces) connecting the components, then sending it off for manufacturing at a foundry in China. The final cost of each board is a little over $5.
As part of learning PCB Design best practices for this project, I completed Altium's PCB Basic Design Course
