Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.

solder defect

Views: 437


solder defect | 20 September, 2019

hello, I have been experiencing a strange solder defect lately. hope some of you may know what is causing it. it happens on same side of processor and there has been no changes in soldering process.


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solder defect | 20 September, 2019

Looks like poor wetting/solderability to me. I don’t see heel fillets on the leads where the solder balls up. The solder has to go somewhere. It won’t flow where it won’t wet. Try printing a bare board and run through reflow. If the solder balls up on some pads it might point to a solderabiliity issue with the board.

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solder defect | 22 September, 2019

Yes, no wetting on the several leads, to verify is same location of the leads? Looks PCB/IC leads wetting issue, a process contaminated or raw material issue. A cross experiments to verify the potential cause is needed.

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