Electronics Forum | Mon Jul 01 15:40:12 EDT 2013 | davef
Walter: The things I'd look at first are: * Temperature of the water wash. I expect the solution to be in the 140-150*F range [Check with your flux supplier for recommended temperatures] * Temperature of the boards when entering the cleaning process.
Electronics Forum | Mon Jul 01 16:34:46 EDT 2013 | wpierowski
So that is common when the temp on the wash is high? The temp was adjusted for a flux that required a higher temp. How much of an issue is this tin oxide?
Electronics Forum | Fri Oct 11 16:25:43 EDT 2013 | scdunlap
Also coplanarity can be poor on these parts so overprinting the paste (beyond the pad perimeter) can increase volume to insure robust solder joint.
Electronics Forum | Tue Oct 15 15:55:09 EDT 2013 | rway
Missing parts should be an easy fix. How many have to be inserted by hand? How do you inspect solder joints?
Electronics Forum | Mon Apr 07 15:22:17 EDT 2014 | garym4569
Found the issue. The footprint is incorrect. The inductor completely shields the paste from heat. Slid the inductor on the pad to expose the pad and paste, and perfect solder joint. This part was a last minute design change with a larger body.
Electronics Forum | Thu Apr 24 12:18:01 EDT 2014 | cyber_wolf
You must thermally profile your circuit boards with a data-logger and thermocouples. Just putting in oven set points and looking at solder joints is not enough. Reference IPC-7530
Electronics Forum | Fri Jan 04 07:44:37 EST 2019 | bane016
Try to measure the profile again by datasheet..with the result that you will reduce the temperature in the areas below...increase the upper temperatures as needed according to the properly measured profile...I hope you can solve the problem like this
Electronics Forum | Fri Jan 04 08:02:03 EST 2019 | ameenullakhan
Hi, Thanks for the valuable feedback. We are at lower spec : ( TAL )Reflow time : Around 50 Sec ( Above 217 deg C) Peak Temp : 240- 245 deg C. Any other suspects. And your English is fine :) Regards, Ameen
Electronics Forum | Fri Jan 18 12:05:47 EST 2019 | SMTA-Timothy
It's unlikely to be a reliability issue. It looks like tin oxide. Nothing to be too concerned about. Otherwise your process controls sound robust.
Electronics Forum | Sat Jan 19 12:00:13 EST 2019 | ameenullakhan
Thanks Dave, For the feedback. It was initially rejected by our customer end. so we had to submit complete analysis report with lab test of the PCBA.
