[Oshpark] BLF SRK FET v3 (46mm / LFPAK56 / Dual+Triple Channel / ATtiny13A+85)

Changelog

The basic circuit follows the one BLF SRK FET v2 by RMM is using. I deliberately designed v3 to only add functions and kept all that was already there, including 2S support with LDO, OTC, Temperature Probing, Switch Pads for Pin 2 and 3, Gate and Pulldown Resistors, Star Solderpads, 5 LED Wire Pads.

You find a detailed partlist when you follow the link to v2, so in the following I stick to the changes and additions.

FET
LFPAK56 instead of D2PAK package

Channels
There are now 3 channels for current regulation

  1. The single AMC7135 (Q1)
  2. The FET
  3. Up to 9 AMC7135 (Q2-10)
    Pin5 of the MCU is hardwired to Q1.
    Pin6 can be connected to the FET or to Q2-10
    Pin3 can be connected to the FET or to Q2-10 as well
    The selection is done with the 4-pad-connector:
    Bridge the pads vertically to connect the FET to Pin3 and Q2-10 to Pin6 (like I did above)
    Bridge the pads horizontally to connect the FET to Pin6 and Q2-10 to Pin3

Capacitors C1/C2 (for MCU, LDO)
I redubbed CLDO as C2
In 2S configuration with LDO you need both capacitors

Momentary Switch
Connect one cable of the switch to SW- (=GND) and the other cable either to SW(2) or SW(3), depending on whether the firmware uses Pin2 or Pin3 of the MCU (Pin2 is commonly used)