7135 Troubleshooting

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allcool
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7135 Troubleshooting

Soldered on 4, 380’s on a Mtn 105 driver like usual.

The math didn’t add up like it usually does. Seems to be missing the extra current of the 12th 7135 chip.
I know its probably my solder job, but they all look good(?) is there an easy way to detect which one is not working..?

Swib
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Yes you can check continuity between the chips that you soldered against the chips already on board. Measure resistance between each pin on the ones you soldered against the same pin on another 7135. Should be near zero. When you find the one that isn’t, resolder.

If you don’t like what it looks like on the wall, take it outside.

Lexel
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it is also possible that one 7135 is dead, even if its soldered OK
there is no way to find a dead or leaking one without unsoldering till you find it

allcool
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Thanks guys, found my problem. Solder looked good, but wasn’t.

Thanks for the advice on finding the leg without continuity…

Lightbringer
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Yeh, and being that they’re all parallelled, just stick the probe in one place (ground, output, input) on a pc trace, and just touch each chip at the right pin.

09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0