Electronics Forum | Tue May 14 20:25:02 EDT 2002 | russ
Hello All, I've got a little problem here. I have a 456 ball PBGA 1mm pitch, .5mm balls, with .6mm pads on the board. given that the pad size is way to big (S/B .45mm or so)I need any and all advice on how to rework these things without shorting o
Electronics Forum | Tue Jul 16 01:28:48 EDT 2002 | ppcbs
Our BGA Rework process has resulted in 100% yield. We always bake BGA chips at 125 degrees C for at least 8 hours before installation. We always bake loaded boards at 90 degrees C for at least 12 hours before BGA removal. Any parts that went throug
Electronics Forum | Wed Jun 26 08:52:03 EDT 2002 | davef
There is no industry standard for reballing BGA. Search the fine SMTnet Archives for a reference to Motorola�s reasoning behind their not shipping product with reworked BGA. As background: * JEDEC is the semiconductor engineering standardization gr
Electronics Forum | Thu Sep 12 10:45:29 EDT 2002 | pbarton
We have used a laser cut stencil 0.15mm (0.006") thick with 0.3mm (0.012") square apertures radiused in the corners 0.06mm (0.0025") to aid paste release. This approach with the (type 3) paste we use has proven successful on thousands of devices plac
Electronics Forum | Fri Oct 04 01:18:27 EDT 2002 | sarge
1.5. Width >= 4-5 Particle Diameters. Use the smallest opening to determine this. Using dimension of the smallest aperture width, you should be able to fit minimum of 4-5 solder balls side by side into the opening. For 0201 design, -400 mesh (type
Electronics Forum | Mon Oct 14 17:28:08 EDT 2002 | msimkin
Russ, Thanks for the feedback. Yeh, we are placing them in production using a full ball detect Yamaha placement machine, 5 thou square stencil. etc.etc. The only reason I raised this concern was from a rework point of veiw (actually, the board desi
Electronics Forum | Mon Feb 03 18:20:57 EST 2003 | Stephen
You mean something like stainless steel balls? I'm racking my brain I seem to remember once doing a job for a customer that involved standing clips being SMT mounted, that a heat sheild clipped onto. Another customer used a "fence" around a bunch of
Electronics Forum | Thu Apr 17 16:43:09 EDT 2003 | davef
Background: * Bulwith, Ronald A., �Failure Analysis of Solder Joints�, �Insulation/Circuits� magazine, February 1978 * Banks, Donald R., et al., �The Effects of Solder Joint Voiding on Plastic Ball Grid Array Reliability�, Proceedings of the Technica
Electronics Forum | Sat Apr 26 20:27:18 EDT 2003 | LWEI
I'm working on a protobuild for a pcba. THis pcba uses double-reflow, paste-in-hole process. On bottom side there is a Ceramic BGA, size 35 X 35 mm, thickness 6mm, over 900 balls count (ball pitch 1mm)and it weighs a hefty 20 grams. Printing uses 6 m
Electronics Forum | Wed May 21 14:44:38 EDT 2003 | blnorman
We currently use Vigon SC-202 in our spray in air system. SC-202 has 830g/l VOC content, so I don't know if that will help reduce your VOC's or not. We used Smart Sonic 440-R in ultrasonic application with great results, but we haven't tried it in