Servo/PWM Pi Hat Overheats

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t-o-m
 
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Servo/PWM Pi Hat Overheats

Post by t-o-m »

I have a problem with the Servo/PWM hat from order 2953791-9009152585 on 11/4/22. The mosfet next to the barrel connector overheats almost immediately when I apply power to the board. I double-checked all of my soldering with a multimeter and there are no shorts introduced by the stacking header (photos attached), but I do read a short across +5 and GND, which I assume is across the mosfet. I have only powered it with the 5V 2A switching power supply from this purchase, and I confirmed that it puts out +5.15V on the center pin relative to ground on the outside of the barrel. Based on other people describing similar problems on message boards, it seems like the only solution is to replace the board.
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dastels
 
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Re: Servo/PWM Pi Hat Overheats

Post by dastels »

Can you post clear closeups of the soldering on the headers. These photos don't show it clearly but it looks messy in places.

Dave

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t-o-m
 
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Re: Servo/PWM Pi Hat Overheats

Post by t-o-m »

It is messy, but I verified with a multimeter that there are no shorts between any of the pins on the header.

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t-o-m
 
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Re: Servo/PWM Pi Hat Overheats

Post by t-o-m »

This is the best I could do with the photo size limits. The problem is with the misfit, which doesn't have any connections to the header. For more context, the problem I'm having is the same as the one here:

viewtopic.php?f=8&t=73584

and here:

viewtopic.php?f=8&t=106367

If it helps, I can do what others have done and lift the mosfet's source and gate and apply power at the capacitor terminals.
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dastels
 
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Re: Servo/PWM Pi Hat Overheats

Post by dastels »

The prognosis seems to be a bad FET resulting in a board replacement. Please email [email protected] with a link to this thread, your order number, and request the replacement of one 16-Channel PWM / Servo HAT for Raspberry Pi.

Dave

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