This is the PCB for my custom HUB75 RGB Panel Display.
I bought this 64x32 panel and this ESP32 (ESP32-CH9102X) closely researching specifications, costing ~30€ in sum. Others will probably work too, no guarantees either way.
Open like regular in KiCad. Look into the docs zip under Actions/KiCad Exports to see renderings.
This schematic can be soldered manually onto a perfboard, but feel free to order a PCB instead.
Use a 5V power supply with 10W or more! Never connect USB Power and Matrix power together, make sure to remove the jumper when using the USB connector. Powering the Matrix via USB, without the terminals, is possible, but definitely not recommended, the devboard can't handle it.
Max current is ~2A, typical ~0.7A, idle (without output) is still ~0.06A, split between devboard and RGB controllers. Being wireless it nice, but usually, especially in this case, not worth the effort for protoypes. While technically possible, the power draw will reduce battery runtime to less than a day.
Feel free to add external solutions though, should be easy to cram a 18650 USP board into the case.
Size and exact positioning is determined by the backing struts of my panel.
Using a 30 Pin Devboard keeps everything compact, but means that IO options are limited. Many pins of the ESP32 have limited usability or are otherwise reserved, check pinouts for reference. This board contains 2 (/3) Touch Inputs for future expansion, a full I2C/SPI/... wasn't included due to size constraints.
Short-circuit-resistance of the power leads is archieved using a polyfuse. Resistance of the inputs is build-in, as they are high impedance, but the outputs are at risk.
Reverse polarity protection is given through D1, which will trigger the fuse. Sure, it's not perfect, but it's simple.
Introducing series resistances into every single connection could have made it safer, but I can't be arsed at the moment. Active-Low or High doesn't really matter either, a cross between adjacent leads would result in one overloading regardless. Feel free to insert ~300 ohm everywhere if you want to be safe.
To be honest, they are virtually identical solutions with just minor differences. Choose according to your needs.