Wiring diagrams and schematics can be found in the PDF files in this folder. There are also Fritzing project files (*.fzz) if you want to modify them.
Note
The files with 5V_ prefix show how a logic level shifter can be used to use a higher voltage in the data signal - using the 3.3V directly from the Pico is out of spec for most WS281x chips, but usually works fine. If you notice glitching when using longer wires for the data line, you should consider using the logic shifter.
Tip
If your lights use 5V power, you can skip the DC/DC converter
Used parts (non affiliate links) confirmed to be working with WS2811 lights:
- Adjustable DC/DC converter: https://www.amazon.pl/dp/B07DK64L2J
- Logic shifter (optional): https://www.amazon.pl/dp/B07NNRS8FS