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ModelCitizen
2015-05-27, 08:40
I've managed to connect an 18v power supply to my (5v) Touch. It doesn't work any longer (apart from making a clicking noise through the speakers when the 18v supply is plugged in).
Is it a bin job or does anyone have any ideas if it might be recoverable? I'm handy with a soldering iron.

Thanks. :-(

Gandhi
2015-05-27, 10:07
I'm sorry to hear that.

Perhaps you could ask the OP of the following thread, if he ever managed to fix it.
http://forums.slimdevices.com/showthread.php?101963-Dead-Touch

philippe_44
2015-05-31, 09:46
I've managed to connect an 18v power supply to my (5v) Touch. It doesn't work any longer (apart from making a clicking noise through the speakers when the 18v supply is plugged in).
Is it a bin job or does anyone have any ideas if it might be recoverable? I'm handy with a soldering iron.

Thanks. :-(

Difficult to say - you might be lucky and just have burnt the power regulation part but it might have gone much further and fried various chips. Do you have pictures of how it looks now ? (I mean the PCB on both side). I've not repaired a touch but many other devices, I'm usually identifying the power regulation part and knowing what it is (linear, step up, step down) I either change the obvious or re-inject the right voltage directly on the board to see if works again. If none works, can change some of the chips when they are standards ... Although it starts to be marginally beneficial in regards to the amount of time spent. You would also need de soldering station

rpress
2015-05-31, 10:06
It's hard to know the damage without poking around inside. I'd start by measuring resistances across various capacitors to see what supply rails are shorted/damaged. If you're lucky it only took out one regulator and you can replace that chip and be on your way. Unlucky it's possible that chip shorted to the downstream components blowing them in the process too.

From looking at a few pics online it seems that there's a couple switching regulators near the power connector. Look around there; it's possible an IC is even burnt/cratered. Once you find the suspect part now you have the problem of finding the part number to replace it with. It's hard enough with SMT components but once they are fried it usually makes the markings unreadable.