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Soldering the SMT BREAKOUT PCB FOR 44-QFN OR 44-TQFP
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Soldering the SMT BREAKOUT PCB FOR 44-QFN OR 44-TQFP

by ataylorm on Wed Jan 25, 2017 7:05 pm

Has anyone bought the SMT BREAKOUT PCB FOR 44-QFN OR 44-TQFP - 3 PACK and if so, have you soldered the QFN side? I'm needing to solder some ATMEGA32U4's to it, and maybe I am just too blind and too shaky handed, but getting the solder on without a template for solder paste seems like it would be very difficult. It doesn't say anything about coming with a template/stencil, so I am assuming it doesn't.

Does anyone have any suggestions for how to accomplish this task? I can heat the whole board with the solder paste/chip on it, just need to figure out how to safely get it in place.

ataylorm
 
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Re: Soldering the SMT BREAKOUT PCB FOR 44-QFN OR 44-TQFP

by adafruit_support_mike on Thu Jan 26, 2017 2:07 am

If you can heat the board, lay some solder paste onto the traces and heat the board once without the chip. That will pull the solder onto the pads, and surface tension will pull most of the solder off the masked regions.

Then you can cool the board and clean up any bridges that might exist where the chip would overlap. Then place the chip using a dab of paste flux to hold it in position, and reheat. As long as you aren't using hot air blowing fast enough to push the chip out of position, the tinned pads of the PCB will bond to the pads of the chip, and surface tension will align the chip to the footprint.

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Please be positive and constructive with your questions and comments.