Electronics Forum | Wed Jan 23 01:24:45 EST 2008 | dragonslong
Hi ppl, i just joined my company as a quality engineer and was revising our incoming visual inspection. I was reading the IPC guidelines of IPC-7095. However, i have some problems which i hope the experts from this forum could help. IPC-7095: At on
Electronics Forum | Mon Apr 23 16:27:28 EDT 2007 | davef
"If you wanna get a "warm n fuzzy" that your cleaner is capable of doing the job. One thing you can do is what I was taught when selecting a cleaner to buy, is get yourself some glass plates (heat resistant tempered glass to be sure!) and make yourse
Electronics Forum | Wed Mar 24 15:15:35 EST 2004 | davef
I think you can effectively clean under any other low standoff device. It's an issue of surface tension, pressure, and flow rate. DI water is the starting point, but the surface tension of straight DI water makes it difficult to get under low stand
Electronics Forum | Tue May 21 17:16:51 EDT 2002 | davef
Larry, Yes, no matter how much you�d like to avoid using NC, you probably will have to start using the stuff, if the design [sales, in your case] types have their way. We can clean WS under 1mm and 1.25mm pitch BGA. For 0.8mm pitch BGA, we use NC.
Electronics Forum | Thu Mar 25 15:27:01 EST 2004 | davef
Thank you Mike. What is your thinking on the use of surficants, as an alternative to saponifiers, for cleaning under low standoff parts? Dreamy: Adding another point to the low standoff part conversation: If you have cleaning issues with 1.27 BGA,
Electronics Forum | Thu Aug 21 08:33:09 EDT 2008 | davef
There is no standard as such. It's easy to see why. It's too complicated and has such a small payoff. Standoff is comprised of: * Package height * Solder thickness between the pad and the component lead * Delta of pad thickness and solder mask For p
Electronics Forum | Fri Apr 06 07:32:33 EDT 2001 | Claude_Couture
Thanks for the tips. I'll have to check with the designers if they can accomodate the height if I was to use parts with stand-off. The bigger holes was already suggested, but they don't want to change them until a new revision on the product comes o
Electronics Forum | Fri Apr 06 07:32:54 EDT 2001 | Claude_Couture
Thanks for the tips. I'll have to check with the designers if they can accomodate the height if I was to use parts with stand-off. The bigger holes was already suggested, but they don't want to change them until a new revision on the product comes o
Electronics Forum | Mon Nov 26 21:41:09 EST 2007 | davef
Shy: Oh, we NOW understand what you're asking. Sorry to be so dense. We agree that the standoff of component from the board could end-up being a little heigher than the pad height when using chipbonder adhesive. We rarely see a problem.
Electronics Forum | Wed Dec 17 11:25:38 EST 2008 | davef
dots of minimal height. So, use a lower viscosity adhesive. * Higher standoff components => larger (and taller) dots. So, use a high viscosity [typically, also high yield point] adhesive.
