LM3875 BrianGT kit not working

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Hi all.

Suddenly the other channel of my gainclone stopped working. :(
When I opened the case, I noticed that the V- wire from the power supply was loose. I reattached it and it still doesn't work. Is it possible, that the loose wire caused the chip to fry? What could I do to find out the reason for the malfunctioning?

Thanks. :wave2s:
 
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My Bad Experience...

I broke the Number One Rule of soldering the other night, I was rushing to finish soldering up the last of my LM3886 amp while EXTREMELY TIRED.

The amp is configured as a single Toroidal Tranny/rectifier/cap bank. I finished and powered her up and saw a little puff of smoke out of my Left Channel LM3886 (yes, they are heat sinked). I then put her away for the night and went to sleep. After work the next day I looked her over and I completely forgot to attach both amps to power GROUND.

I replaced the smoked amp board with a new one (the other channel seemed fine), connected the Power GROUNDS to both amp boards and all was good with the amp.

Now the smoked chip. I looked at under a loupe and the #6 pin is charred - and #6 pin is No Connection. I am perplexed at what I could have done. It is next to the #7 pin which is GROUND. Looked over the PCB and nothing else seems amiss.

Any thoughts? And beside reconnecting the board, is there any way I can check to see if the LM3886 chip is really fried with a MM to the chip pinouts?)

I can get a new chip for $3.50 and replace it, but these chips are pretty indestructable, aren't they? And I hate DESOLDERING !
 
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