Electronics Forum | Fri Mar 26 03:24:01 EDT 2010 | ravikumarasahitec
Hi, yes we used to see this kind of problem our customer end. This due to stencil aperture opening.these kind of issues we will overcome thorough our stencil process. please contact. ravikumar@asahitec.in
Electronics Forum | Thu Mar 25 12:34:26 EDT 2010 | bgaguy
the voids will cause a long term relability problem as the part will not be correctly heatsinked. Change your stencil aperature to a "+" sign 15-20 mils wide in the center of the pad. ___________ : | : : | : :----|----: : | : :__
Electronics Forum | Wed Mar 24 11:09:44 EDT 2010 | rajeshwara
Hello Sir I faced the same problem for QFP in DTH product in India. IPC stated that void should not be more than 25% of solder joint. But this type of void definatly create problem during functional test. Please check the folloeing point... 1.Check t
Electronics Forum | Thu Mar 25 11:30:33 EDT 2010 | Sean
Hello Rajeshwara, If not mistaken, the 25% solder void specification is for BGA...As I I as know, no specification given to mosfet component yet..I think you are right, I need to look at the stencil aperture in order to reduce the air trap underneat
Electronics Forum | Mon Oct 13 13:49:29 EDT 2003 | mrmaint
Does anyone know of a standard stencil thickness for BGA'S. We currently use 4 to 5 mil stencils depending on component mix. Is an aperature reduction required for BGA'S. If so what percentage. Any help would be greatly appreciated. Thanks MRMAINT
Electronics Forum | Fri Jan 03 11:42:38 EST 2003 | soupatech
Hi, I am loading a new board with mostly 0603 packages. The pads are .5 mm apart and I am having a big problem with parts shifting towards eachother instead of centering on the pads. I believe this is caused by too much solder. I am using a 7mil sten
Electronics Forum | Sat Jan 04 09:02:17 EST 2003 | davef
Q1. What is the recommended stencil thickness to apply the proper amount of solder for 0603 components? A1. The proper amount of solder is determined by: * Metal content of the solder paste. * Stencil thickness. * Aperture opening. * Other factors,
Electronics Forum | Thu Jan 09 10:58:30 EST 2003 | soupatech
Thanks for the input.... I ordered a 5 mil stencil AND used more tooling under the board. This gave me a much smaller deposit of solder. I wouldn't swear that was my problem but 96 boards later the problem is 99% gone. I believe there was just too mu
Electronics Forum | Mon Oct 13 19:04:47 EDT 2003 | davef
Aperture size should vary with the component [pitch]. That size should be the same a the pad size. So, generally pinching is not required. Indium discusses BGA apertures on their site [ http://www.indium.com ]
Electronics Forum | Fri Jan 03 12:01:46 EST 2003 | jax
Alot of the companies out there use Standards developed internally, centered around there paste, equipment, and reflow processes. Normally you will see either 5mil or 6mil stencils used for everything in house with the exceptions of specific boards.(
