Image:Half-completed manual soldering of surface mount MQFP integrated circuit.jpg

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[edit] Summary

This image shows a 32-pin MQFP (Metric Quad Flat Pack) surface mount integrated circuit half way through the manual soldering process. 16 pins have been soldered with wire wrap wire, which will later be fixed into a DIP chip holder.

[edit] Technique/advice

1) If you must manually solder an IC, make it one with legs that stick out. ICs like this one aren't very solderable, because the pads are 'printed on', so if you heat them up too much/too many times, you'll find the pad disappears... I found that, anyway.

2) You need the IC held in place really securely. I did this by blu-tacking it to a lump of steel. Double-sided sticky tape also works.

3) You need to solder left to right, so you can hold the iron in your best hand and not foul pins you've already done.

4) Make sure you have a sharp soldering iron and something to clean it on - usually a wet sponge.

5) Strip the wire-wrap wire, put a dab of solder on the end, put the dab of solder against the IC pin, then touch your soldering iron against the two of them. This should melt the solder onto the pin, securing the wire in place. Don't bother trying to tin the pin or anything; they're too small.

6) If you've done it right, you'll be able to move the wire a bit and it will bend on the wire, not at the solder joint. Inspect it with a good magnifying glass to avoid solder bridging. Check it regularly; you want to fix your mistakes before you put the next wire on.

[edit] Licensing

Photo taken by Mike1024.

This image is copyrighted. However, the copyright holder has irrevocably released all rights to it, allowing it to be freely reproduced, distributed, transmitted, used, modified, built upon, or otherwise exploited in any way by anyone for any purpose, commercial or non-commercial, with or without attribution of the author, as if in the public domain.

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(del) (cur) 14:58, 15 October 2005 . . Mike1024 (Talk | contribs) . . 1024×1024 (105,776 bytes) (==Summary== This image shows a 32-pin MQFP (Metric Quad Flat Pack) surface mount integrated circuit half way through the manual soldering process. 16 pins have been soldered with wire wrap wire, which will later be fixed into a DIP chip ho)