Accidentally plugged in to a 12v adapter, won’t boot

[Morpheus_79]

It’s hard to tell… cause most of the ICs and a lot of filtering caps are connected to the IOVDD line:

You can try to remove U4… maybe U8… and all the filtering caps connected to IOVDD and GND… before removing the bigger ICs. If you have the opportunity to borrow a heat cam, you could try to induce some low voltage into the IOVDD line and check for heat spots.

[s0urceror]

Thx Morpheus for your reply and highlighting the corresponding traces.

I checked the schematics already and figured out that indeed IOVDD is connected everywhere. Was hoping there was a likely culprit. The 12v probably triggered an over-voltage behind U5 which led to a short somewhere. ICs usually just fail without creating a short. Filtering caps usually just survive unless they are of the tantalum kind which short. Do we have tantalums anywhere on the board?

Anyway, I’ll keep checking, thx.

Btw. I got myself already a new OSSC but want to revive this one as well. One cannot have too many retro video converters 😉

[Morpheus_79]

No… we don’t have any tantalum caps on the pcb. And you are right: filtering caps usually don’t fail… but i’ve seen them fail in the past. And if some of the used ones are only rated for 6.3V, they may short out after a significantly higher voltage – unlikely but possible. It’s the same for the ICs: a short to ground because of the overvoltage is unlikely… but not impossible. But those should be the last ones to test…

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