Electronics Forum | Wed Mar 17 14:59:53 EST 2004 | Claude_Couture
since there is a bit of humor in this thread, try drilling the pads from the opposite side of the pcb.
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 Mar 19 10:06:22 EDT 2010 | karlo
Rework is typically done by heating the BGA to 170-180C to first scrape off the fillet. Then, heat to above reflow, and lift the BGA. Then, collapse the solder with heat and flux. Then, back down at 170-180C, scrape off the underfill from the boar
Electronics Forum | Wed Aug 29 03:16:20 EDT 2018 | cannizzaro
It is recommended that the thickness of the stencil of 0.1mm, the steel mesh should be partially nano-coated. It is best not to dry easily, and the particles are not easy to be too large. I have tried ALLPCB for this kind of BGA in the past and they
Electronics Forum | Fri Aug 22 00:20:29 EDT 2008 | rameshr
Hai, In our process we are using the micro bga of size 13X13mm of pitch 0.45mm,after soldering process the bga found collapsed, we absorbed that the PCB land pattern of the BGA was not in array, uneven distribution of pads (area) & most of the pads
Electronics Forum | Wed Aug 27 08:25:24 EDT 2008 | davef
We'd expect to see: * Solder starved connections at pads with large trace/pad areas. * Less reliable solder connections at pads that do not match the shape and size of the corresponding pads on the component.
Electronics Forum | Mon Aug 25 10:36:05 EDT 2008 | davef
Yes, it's peculiar that the layout of this board is so disorganized * Pads are not round, uniform, or the same size * Exposed traces have different thickness
Electronics Forum | Fri Aug 22 03:19:08 EDT 2008 | andrzej
Hi, what do you mean by collapsed ? Can you describe or send a photo ?
Electronics Forum | Mon Aug 25 08:44:10 EDT 2008 | rameshr
Dear Andrezj, i had attached the photos for ur reference Kindly advice.
Electronics Forum | Wed Aug 27 00:20:38 EDT 2008 | rameshr
Dear davef, Will u pls advice what are all the possible defects caused while soldering ( assembling ) this type of boards.
winsouce.jpg)
