11/18/2023 at 14:02 •
This is my badge hack for the 2023 Supercon badge.
Before the con, I designed a LED frame in Fusion360 for resin printing based on the published Gerber-Files.
This frame has space for 280 WS2812B LEDs in 1010 package (1x1mm). There are cut outs for the on/off switch and the Pi Pico.
The holes for the LEDs are rotated by 55° to make soldering easier when bridging DIN and DOUT. GND and VCC can be bridged with wires.
One day before leaving to LA, I printed the frame on a resin printer. with white resin. Had some issues with warping, so the frame is slightly shorter on one side. Also laser cut a MDF dummy for holding the frame during transport and assembly. Placing the LEDs and hand-soldering happened during the con on Friday and Saturday.
Used a PINECIL USB-C soldering iron with the smalles tip available and 3.5x magnifying glasses. The bridging of GND and VCC was done with a 30 Gauge wire from a roll.
First successful light-up was on Saturday evening after 1.5 days of soldering.
Some close-ups under the microscope made after the con.
The first LED is connected to GPIO28 of the Pico. Animations are now running in Micropython using this lib and the original firmware from Supercon. Had to increase the OS update frequency to get proper anmiation update rate. Brightness of the LEDs is around 25%, but because of the high density, this is already super bright..
Also, I designed a LiPo battery holder for the badge to handle the current for the LEDs. The files for the battery holder are published at printables.com.