This is the spiritual successor to the SMOL, a tiny PCB that interrupts battery output to make fun patterns. By designing around a 10mm-by-44mm LiPo cell, I've been able to add Wi-Fi connectivity, a USB connection for charging and programming, and a dangerous (but intriguing!) overvoltage mode.
The star of the show is the ESP32-PICO-D4, a 7mm-by-7mm powerhouse. It handles the wireless networking and various GPIOs.
Hardware developed in KiCad 5.1; firmware built in the Arduino IDE. Licensed/Licenced with the CERN OHL. Documentation covered by Creative Commons Attribution (CC-BY) 4.0.
Bill of materials is here. An interactive HTML BOM is here. Assembly and initial setup is covered here.
A pdf version is also available.
- Add pictures to setup/assembly instructions
- Improve the user interface
- Generate renders
