Electronics Forum | Mon Dec 17 13:58:54 EST 2007 | ck_the_flip
I made my own wave measuring device using KIC2000 system. KIC2000 has automatic wave detection, so now I have a profiler for both reflow ovens and wave solder. The delmat carrier only cost $500. A guy, Samir, from this forum gave me the idea, actu
Electronics Forum | Fri Mar 04 01:08:19 EST 2011 | kemasta
Thanks davef Bridging:- There is no heat sink on the BGA, the heat sink will be fix after relow. I do believe paste had something to do with it, but currently this defect didn't appear so oftenly, so we think that the main root cause is not from the
Electronics Forum | Mon Mar 21 02:54:58 EDT 2011 | kemasta
Hi Dave I agree with the 2nd point (sloppy process management) if the failure rate is higher than 5%. But this is 0.083% case, and only happen once in the blue moon. As I study about the re-flow profile for the last whole week, current parameter se
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 | 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 | 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?
Electronics Forum | Thu Apr 06 00:27:42 EDT 2000 | Dean
I would check their data sheet for the particular product. Thats the range I have for Some Kester products I use... Are you seeing any slumping prior to pick-and-place? Is the bridge in the same place every time? How is your pick-and-place mounting
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
