As you know, the Raise uses about 140 LEDs, with about 70 in each half. Thirty-five (35) are used for the keys and the rest for the underglow. For cost reasons we are using plain RGB LEDs instead of the smart type like WS2812s. That means instead of a simple serial connection in between each LED, we need to wire each R, G, and B of each LED – which makes for a lot of wires!
One way to solve this is to use a special LED matrix driver chip, where all the LEDs are laid in a matrix and the chip does some complicated pin wiggling to set each LED to the brightness we want.
Here’s a small portion of the matrix we use.
During testing we noticed that a lot of red LEDs that should be off, would turn on dimly when other LEDs were powered up. This video explains why that happens and how we resolved the issue.