Electronics Forum | Tue Feb 22 10:44:12 EST 2005 | Dougs
when you talk about stencil design, what would you recommend for aperture size on fine pitch if the customer insists on hasl finish on fine pitch devices? i usually use a 10% reduction on everything we have been using ( 16mil pitch and upwards and 0
Electronics Forum | Wed Apr 27 10:47:26 EDT 2005 | HOSS
A 1:1 pad to ball diameter will cause the balls to collapse more giving you less post solder component standoff. Depending on the application of this product and required reliability, you may want to stay with the padstack being used. You may try c
Electronics Forum | Tue May 25 11:40:23 EDT 1999 | Steve Gregory
Just a note about cleaning stencils with a mixture of alcohol and water, especially if you're using no clean paste, it's really not recommended. Don't take my word for it, you can check with Alpha or most any other solderpaste vendor. What will actu
Electronics Forum | Wed Dec 15 18:03:28 EST 2004 | russ
I have used both 4 and 5 mil stencils for 10 mil round apertures. We don't have volume measurement capability but we measure height and the 4 mil appeared to have more paste and better uniformity from a visual standpoint than the 5 mil. The unfortu
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 >
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