EEVblog Electronics Community Forum
Electronics => Repair => Topic started by: bitshift on October 14, 2015, 04:02:45 pm
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Hey guys,
I was attempting to solder a SSOP28 IC to a home etched PCB this afternoon. While tacking down one of the corners, I accidentally bridged two of the pins. After using some solder wick to remove the bridge, the copper going to the second pin lifted off the board. I managed to solder the rest of pins good enough. Please see the image below. The piece of copper in front of the first and second pins is the part that lifted off the board. It should be a trace going straight to the second pin.
(http://bitshift.co.za/forum-files/ssop-missing-pin-copper-small.png)
Here (http://bitshift.co.za/forum-files/ssop-missing-pin-copper.png) is a link to a higher resolution image.
My first thought for fixing this was a bodge wire, but the thinnest wire I have is around 1.5 pins wide. How else could I go about repairing this?
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There won't be too many alternatives to a bodge wire, I'm afraid.
You sure have some stranded wires in your drawer? Take one of them and pull one single wire out of the bundle ...
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The stranded wire is a great idea. Thank you :)
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The wire strands worked great! I ended up twisting 3 or 4 of the strands together though. Thank you Performa01 :-+ Here's a pic for anyone interested:
(http://bitshift.co.za/forum-files/ssop-missing-pin-soldered-strands-small.jpg)
Here (http://bitshift.co.za/forum-files/ssop-missing-pin-soldered-strands.jpg) is a link to a higher resolution image.
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This one worked out pretty well, didn't it? Good job! :-+
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Bitshift thanks for the post. I am impressed with that repair job, I will have to try that if I am ever in a situation like that.
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Great repair job! That said, next time, instead of solder wick, just use a chisel tip (or a drag soldering tip if you have one) and drag off the solder bridge — no wick needed!
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That's some top quality bodge right there! Well done! :-+
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Yes, very nice! And a great idea to use the individual strands from some stranded wire... I might not have thought of that myself.
Here's my very first try at replacing a "large" surface mount chip, some years ago. It's a motor controller from a Celestron CGEM telescope mount. I had to replace some entire traces, as you can see, using #30 wire-wrap wire. I did use the "Chip-Quick" stuff to get the old one off. Probably still used too much heat since traces lifted, etc.
But it works! Still using it in my mount, although I have a complete replacement new board in the drawer, waiting for the next big failure....
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I find a couple of plain copper (not tinned) strands work the best. I have repaired dozens of boards in this way over the years. I've also ground away the plastic casings of IC's and attached a wire directly to the leadframe, then sealed it with a drop of epoxy. When you have nothing to lose.....