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Topic: I think I messed up bad. (Read 632 times) previous topic - next topic

Agent_47

I had a board to solder my atmega 328 tqfp and as i was soldering i put what i thought was a little drop of solder and when i dabbed it on BLAM all the connections on one side were all one, i tried to desolder it but theres still a little bit of solder that i cant get and is connecting the pins still, I need help on getting that little bit out. Also I think maybe spending about 15 minutes reheating the solder in the chip so many times i think i may have fried the chip ( I was just thinking that may have happen by something inside maybe melting, I haven't tested the chip out yet). I would greatly appreciate your help thanks.

CrossRoads

You need a "solder sucker",  heat up the joint and suck solder off.
Or you can try solder wick braid, maybe with liquid flux added.

If you've reheated the board that many times, you might have damaged the traces as well.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

Agent_47

Thanks

I'm self teaching, shit happens.

CrossRoads

I totally understand. I have a promini that is dead, I was probing signals and something got loose on a breadboard and shorted something out and fried the processor. Haven't tried to replace it yet.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

MarkT

I've found two ways to solder SM chips.  One is to use lots of solder and a sucker to remove the excess (problems include the recoil from the sucker damaging the traces).  The other is the minimal solder technique which I think is better:

First wet all the pads on the board for the chip so they all have a little smooth bulge of solder.  You may have to suck off excess if solder bridges neighbouring pads.  Then carefully hold the chip in place and tack solder down one pin (with a freshly tinned and wiped iron) - the solder on the pad should be enough to make the joint without any risk of bridging.  Then again carefully tack a pin on the other side of the chip - make sure all the pins are aligned on pads and tack down the rest.  Examine with a lens to spot any dry joints.  The tricky part is holding the chip in pace as the pins like to slide between the bumps on the pads.
[ I won't respond to messages, use the forum please ]

mowcius

Tinning pads beforehand is the way to go. Sometimes tinning the part legs is a good plan too.

Solder wick is good though (although I still don't actually have any of my own).

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