Powering M0 using higher voltage batteries instead of LiPo

[akstudios]

I have an M0 that I'd like to power via a bank of 8 AA batteries that add up to 12V. This is only in my specific use case where I need a higher voltage elsewhere in my circuit and would like to power the M0 directly from the VBAT/VIN pin. I won't be using the charger, so I'll take that out of the board as well, to avoid the reverse current flowing into the battery bank and exploding it.

My question is - would this still work? I know the voltage regulator should be rated up to 16V, but what about everything else? If we have 12V on the drain of MOSFET Q1 instead of the usual 3.7 to 4.2V from the LiPo, I guess things should still be okay? Not sure what part is being used here. But I'm assuming the Vgs(th) is low enough that 5V from USB would be shutting it off regardless of what is connected on the drain.

Alternatively, I can replace it with a P-channel FET that has a higher voltage rating if this doesn't suffice. Are there any other things I need to consider before I plug all of this in?

[Felix]

Look carefully at the board silkscreen, it says VIN 3-6V.
If you feed anything more than 6V into the JST connector or broken out VIN pin you will fry the charger chip.
FWIW The "VIN" in the schematic is not the same as the VIN on the edge of the board.
This board was designed for VIN up to 6V, I would not use it with anything but 55 thru USB or typical LiPo through JST.

[akstudios]

Yes, that's why I mentioned that I'll remove the charging chip from the board just for this project, since I won't be using it and it'll simply burn up if I put in more than 6V. I was wondering if there was anything else on the board that I need to worry about before attempting this mod.

I should mention that this is more of a custom project and not an inquiry about Moteinos' features as guaranteed by Lowpowerlab. I'm fully aware that I'm voiding my warranty and at risk by whatever I do beyond what the board is advertised to do. Perhaps this post should be moved to the projects section.

[Felix]

I think any mods imply they are done at the user's risk. I put up the schematic for reference, but it's not there to encourage mods necessarily, but if someone is confident and knowledgeable they can hack away. My guess is if it comes to that, it would be more convenient to design another board entirely, except if you only need a quick 1 time mod like this.
I think someone else asked the same question but I'd have to look around the forum to find it, essentially the charger is the only 6V limiter, otherwise the MCP can take up to 16V theoretically, although I've never recommended to push it to that limit, nor have I ever tried.