Electronics Forum | Thu Apr 14 13:24:18 EDT 2016 | davef
I doubt that your problem is driven primarily by irregularities in your circuit board. My bet is that you’re seeing defects caused primarily by the warpage in your LGA. Consider using advice often given for minimizing warpage caused defects in BGA
Electronics Forum | Tue May 18 14:15:59 EDT 1999 | Scott McKee
| | What is the best way to re-ball a BGA? Who has the best system for doing it? | | | I'm using our SRT rework stuff to reball in house - when necessary. Of course, we only do this for protos and test boards. We use a standard micro-stencil, after
Electronics Forum | Tue May 18 16:48:49 EDT 1999 | Tony
| | | | | What is the best way to re-ball a BGA? Who has the best system for doing it? | | | | | | | | | I'm using our SRT rework stuff to reball in house - when necessary. Of course, we only do this for protos and test boards. We use a standard mi
Electronics Forum | Fri Apr 13 10:13:30 EDT 2007 | Bob R.
We had a crisis with one BGA causing huge yield losses due to this defect. Nothing we could do with the profile got rid of it. Changing paste didn't get rid of it. It was the BGA warping in reflow, caused the corners to lift up when the solder was
Electronics Forum | Wed Feb 07 09:46:20 EST 2001 | pjc
I need some guidance here. I've got a new board w/ a FBGA-48 package, Samsung CMOS SRAM. It's a full matrix BGA w/ 0.30mm-0.40mm ball diameter @ 0.75mm pitch. Balls are eutectic. PCB land diameter is 0.4mm. There are TSOP I 0.5mm lead pitch component
Electronics Forum | Mon Nov 12 09:22:41 EST 2007 | devajj
BTW, The surrounded QFN fine pitch terminals > should have the normal aperture reduction of 7 % > in case of RoHS Senju solder paste. This works > for our Telecom customer. > > The vias in the > ground pad will be somewhat filled with solder >
Electronics Forum | Mon Oct 14 17:59:45 EDT 2002 | russ
When I used the micro-stencils, We purchased the holder from the stencil manufacturer. As far as design we used 5mil stencils for uBGAs,6-7 mil for larger 63/37 balls, and 8 mil for CBGAs. Aperture openings used were slightly smaller than what we wo
Electronics Forum | Tue Nov 11 09:19:17 EST 2008 | davef
By the way you asked the question, we assume that by "reballing" you mean bumping, we should be able to figure that out: * Volume of the ball = ( pi*d^�)/6 = [355/113] *0.6*0.6*0.6]/6 = 0.11mm^3 * Volume of solder required = 2*volume of ball = 2*0.11
Electronics Forum | Tue Sep 01 20:36:05 EDT 1998 | Rin Or
| We are experiencing shorting on a BGA. The part has a 1mm pitch with a 196 I/O count. The problem seems to pop up without warning & disappear in the same manner. | Our pad design is .020" diameter pads with .025" solder resist diameter. The ce
Electronics Forum | Fri Apr 29 17:49:22 EDT 2005 | Woodsmt
I have used many of these devices recently and have used them several times over the last few years. I have been successful using a type 4 paste on a 5 mil stencil. The 13 mil round aperture should provide you with an area ratio just adequate for r
