Electronics Forum | Fri Feb 25 09:30:29 EST 2011 | kahrpr
Was the void on the same pad for the 5 failures or were they random
Electronics Forum | Thu Apr 06 07:53:35 EDT 2000 | jacob lacourse
I have also come across this very same problem and found that our screen vendor made a mistake on our screen. Check the thickness of your screen it should be about six thousandths if it's eight thousandths then you are most likely depositing to much
Electronics Forum | Thu Feb 24 23:11:51 EST 2011 | kemasta
HI I have this BGA short issue, I took x-ray image, the solder ball having big void. We suspect the pad on BGA was oxidie. Reject percentage quite low, only 5 out of 6000. But after the BGA re-ball, is work fine. Anyone have any idea to trobleshoot
Electronics Forum | Thu Apr 06 08:31:13 EDT 2000 | D Scott
Angela Do you see this problem on other .5mm pitch devices or is it only on the QFP? Check placement height, too low or to high can cause you problems Pad co-planarity, are your boards HASL? Is your board sagging during placement(board supports) An
Electronics Forum | Thu Mar 03 08:06:36 EST 2011 | scottp
I've seen this with through hole via in pad with soldermask plugging from the opposite side. Baking the boards solved it. Not using such a horrible via in pad method would also have solved it, but that wasn't an option. Is this ball sitting on a v
Electronics Forum | Fri Mar 04 00:46:36 EST 2011 | kemasta
Hi ScottE "Is this ball sitting on a via?" I am not sure is I answered your question correct, the ball is sit on the pad.
Electronics Forum | Tue Oct 10 20:14:01 EDT 2000 | Dason C
Hi! CJ. Please advise what is your pitch size ie 15.7 mil or what is your capabiliy can you build the board with pitch 15.75 mil (please note that the actual dimension of the package is 0.4mm), and how many lead on the package. The pad width of Ind
Electronics Forum | Thu Nov 17 21:46:48 EST 2005 | C. Kolokoy
With DIP type components, a sub-par fluxing method (foaming a no-clean), and a chip wave where one is not needed are formulas for bridging and insufficient wetting. If you have SMD's on the wave solder side of the board greater than 0603, and no SOT
Electronics Forum | Wed Apr 05 23:56:02 EDT 2000 | angela
Recently we have serious problem of our 0.5mm pitch QFP solder bridge. I check the viscosity of the Litton Kester paster. It's roumd about 700 is it too low. And do you have god solution about it? thanks alot
Electronics Forum | Mon Feb 28 23:07:04 EST 2011 | kemasta
It is random. By the way, this board pass thought wave process, (BGA is at the top), will that cause the older short issue?
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