this post was submitted on 12 Sep 2024
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I've been messing around with circuits my entire life but this design was time sensitive and I've never done my own PCB designs before, so I hired someone to put this together. After getting some test boards, when I plug them in the charger chip gets very hot and smells like burning....

Circuit is just a simple li-ion usb charger and a switch. I've gone through the datasheet for the bq25302 more times than I can count and I'm missing something obvious here. Using it just for delivering power seems to work fine, the problem is only when charging.

I do see R6 + R7 off TS don't have the recommended 10k values, but I don't feel like that would cause what I'm seeing. This is being connected to a 21700 lipo.

Someone mind lending me their eyes please?

bq25302 datasheet - https://www.ti.com/lit/ds/symlink/bq25302.pdf

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[–] Shadow@lemmy.ca 2 points 3 months ago

STAT should have a current limiting resistor on it, go through your led, then ground.

That would make sense, but page 21 of the datasheet with a typical application shows it going to REGN.

If it's missing the cap on REGN though, that would probably fuck this all up? I must admit I'm not good at understanding when/where caps are applied.