Hi,
I’m using a LiPo SHIM to power a PI and would like to know if the schematic is available somewhere because I want to change the UVLO of the boost and the low battery warning voltage and I really would hate to have to desolder each resistor measure it and reverse engineer the schematic.
Thanks for the support and sorry for the maybe awkward question, if you don’t want to share the schematic I totally get it. It would only make my life a little easier.
Mh
Unfortunately Pimoroni generally don’t release the schematics for their boards. If you look at the photos on the product page you can read the values of some of the resistors, a magnifying glass might help you to get the rest.
It’s a kinda easy circuit.
The TPS61232 has three resistor between VIN, EN and HYS for the UVLO.
Then there is the comparator for the low battery that is powered from the 5V out and I guess a resistor divider for the comparator threshold. The real problem is that there is also a level shifter for converting the 5V out of the comparator to 3V3 for the pi and the black PCB silkscreen doesn’t help with tracing so I guess I’m just going to design a custom PCB at this point as it will require less time than reverse engineer the LiPo SHIM.