Been having some fun recently designing an RGB backlight solution for the Ergodox, I welcome all comments, suggestions, modifications and pull requests.
1. The design uses one mid-high power RGB LED per half, a light pipe is used to direct this into .75mm fiber optic cables, one per key.
2. The optical fibers are routed via a hole to the back of the keyboard where each fiber is routed to the key in question and up just like one lead for a normal key LED.
3. There are several components to this, rather than building my own driver(s) for the LEDs and to maximise efficiency for the 500mA USB limit I used a ready made driver.
4. Components:
- 2x LM3549 - $14.2@Mouser
- 2x LPF-R011362S $1.5@Farnell
- 2x RGB LED LRTB C9TP $7.14@Mouser
- 80x 0.75mm Fiber Optic cables, 200mm each $14@Ebay
- 2x Capacitor 10 µF,6.3V/10V X7R C1206C106J8RACTU 3.88@Mouser
- 2x Capacitor 4.7 µF,6.3V/10V X7R C1206C475J8NACTU 2.74@Mouser
- 2x Inductor 2.2 µH, 1900 mA L1210R2R2MDWIT 1.866@Mouser
The driver is configured via I2C so it uses the same bus as the keyboard halves communicate with and the LED can be placed on either side although the controller and parts are confined to a single side only.
Total buying individual components: $42.3
Total when buying in bulk, approx: $20
Here is a snapshot of the PCB as it is currently:
[ Specified attachment is not available ]
I still need to work on the masks, case modifications, some more PCB mods and optimisations but I think the design should work.
The PCB and Schematics are already on Github:
https://github.com/jalli/ErgoDox
