2 layers125 × 45 mm

Promatrix-4000-IO
giomf/Promatrix-4000-IO
8-output / 7-input digital IO board (RP2040-based) with USB serial control.
30 parts
Boards in 2 GitHub repositories, designed in KiCad, that use the PC817X3CSP9F by Sharp Microelectronics (-30℃~+100℃ 1 1.2V 200mV@20mA,1mA 200mW 3us 4us 50% 50mA 50mA 5kV 600% 6V 80V DC Phototransistor SMD-4P Transistor, Photovoltaic Output Optoisolators ROHS). See how each wires it, with its parts, size, README and files; the PC817X3CSP9F’s symbol, footprint and pinout are on its own page.

giomf/Promatrix-4000-IO
8-output / 7-input digital IO board (RP2040-based) with USB serial control.

Karma7272-cmd/ESP-32-kicad-design
A collection of my electronics circuits, PCB designs, and hardware projects in a single repository.