This is the bare PCB you need to build your own 20mm FET driver! DIY parts kit available here.
This updated version makes spring bypasses a breeze---simply run your LED+ wire directly to the spring.
- FET: LFPAK56 N-Channel Mosfet
- D1: SOD-323 Schottky diode
- C1: 10uF MLC capacitor, 0805 (X7R preferred)
- Populate CZNR instead of C1 if used zener modified
- R1: 19.1K, 1% resistor, 0805
- Use 36K 1% 0805 resistor for 2S or 3S zener mod LVP
- R2: 4.7K, 1% resistor, 0805
- UI: ATTINY13A MCU, SSH or SSU variant
- Z: SOD-323 4.3v or 5.1v zener diode
- If zener diode is used:
- populate CZNR instead of C1 with 10uF capacitor
- replace D1 with 200 ohm resistor
- Spring / LED leads
- OTC: 1uF MLC capacitor, 0805 (X7R preferred)
- Pad with side closest to MCU can also be used as electronic switch pad (no OTC installed).
The parts layout is the same for the 17mm and 20mm boards.