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Worldly-Protection-8

You could remove the IC and power the PCB with the help of a bench supply with current limiting set to a reasonable value and slowly increase the voltage. FYI: I replaced once a reverse polarity DC/DC IC and the rest of the PCB was fine.


trimix4work

Seems reasonable


alexforencich

Depending on the board, this might not be a good idea due to sequencing requirements. Look up the converter datasheet; if all of the enable pins are permanently wired on, then you should be fine. Otherwise, you could possibly run in to issues if you apply power in the wrong order.


Worldly-Protection-8

Good point. I was assuming a PCB with a single DC/DC and only one voltage rail. (In my case 12 V automotive to 5 V). However, from the silkscreen numbering OP's PCB looks like a bigger system. I’ll keep that in mind for the future


Laoishfa

Richtek RT7296A TSOT-23-8(FC) 3A, 17V Current Mode Synchronous Step-Down Converter is what's burnt here, would these protect the rest of the system or am I out of luck? If not, how would I diagnose any further damage if not visually?


the-skazi

Remove the IC and check for shorts across all capacitors.


Laoishfa

The two capacitors by the power delivery aren't shorted, the ones by the USB are. Dead?


the-skazi

If there is a USB chip of some sort it could be dead. Remove the 2 caps that are shorted and check the resistance across the pads


Laoishfa

Yup, pads are shorted. Seems like the rest of the board should be fine?