Just fried a Photon, trying to narrow down why. I was doing analogRead on A6 and A7 (DAC and WKP i think) using a I2C breakout available on a PhoBot shield. Didn’t occur to me that the breakout was for I2C @ 5v. I was also supplying 13+ volts (12v lead-acid battery on solar, using a charge controller output) to the shield when the spec said max 12 (though the PhoBot states 12v max in, the onboard CJ1117 looks like recommended is under 15v). It won’t turn on anymore, and smells funny / gets hot when powered by USB.
Is it more likely that I friend the regulator with the ~13v+ or could I do more than just kill a pin by supplying over 3.3v input on an analogRead.
Edit: Added links to product and hardware schematics for PhoBot shield and CJ1117 regulator.