Electronics Forum | Fri Sep 11 00:52:19 EDT 1998 | Rick Thompson
| I'm very familiar with the great board space savings of BGA and all the "claims to fame." However, can someone out there tell me if any concern exist in the inspection realm. Additionally, solder cracking, CTE/TCE mismatches, no leads for stress re
Electronics Forum | Thu Sep 10 10:07:46 EDT 1998 | J.H Kim
I'm very familiar with the great board space savings of BGA and all the "claims to fame." However, can someone out there tell me if any concern exist in the inspection realm. Additionally, solder cracking, CTE mismatches, no leads for stress relief,
Electronics Forum | Mon Dec 31 08:59:36 EST 2001 | Don Adams
The second pass in the wave is pretty extreme and will probably aggravate the conditions which caused warpage in the first place. Areas to look for problems, The lay up of the boards at fabrication or the materials used can lead to warpage. Work wi
Electronics Forum | Wed Jan 07 07:16:25 EST 2004 | davef
Cold solder prior to properly performing a well designed drop test. Actually, "cold solder" means different things to different people. Two dull solder connection conditions are: * "Disturbed" solder joint: a solder joint that has an "angular face
Electronics Forum | Tue Jul 05 16:29:27 EDT 2005 | stepheniii
The air kiss is to replace the vacuum with air so the part will drop off the nozzle. Every machine I've seen with Air kiss, uses it when discarding a part as well as when placing a part. The air kiss should not be strong enough to blow the nozzle off
Electronics Forum | Thu Nov 17 15:40:23 EST 2005 | Hoss
We have a board that has been diagnosed with inner layer separation from the barrel wall. This board is .093 thick and 12 layers. Several layers, in some cases, have little or no thermal relief making soldering difficult. We have since switched t
Electronics Forum | Sun Feb 25 11:59:33 EST 2007 | stepheniii
Just make sure you keep the half done assemblies in dry storage or do the second reflow within the time dictated by the BGAs MSD rating level. Maybe this time you did the second side with a very short wait because you were anxious about the results
Electronics Forum | Fri Jul 13 18:25:09 EDT 2007 | seankim10
It sounds like more has to do with plating. you may also check out the voiding issue especially if you have new FAB or the supplier. I had problems with a RF chip in QFN package due to insufficient grounding that voiding caused. This ground is often
Electronics Forum | Thu Mar 20 17:39:41 EDT 2008 | boardhouse
FSW, Another suggestions is if you have rail on your product and you are concerned about stress fracturing certain components you could add a routed slot to add relief in that area. So when you snap the rail off their would be no stress in that area
Electronics Forum | Wed Jun 01 15:50:59 EDT 2011 | markhoch
I don't believe that particle size of the solderpaste will offer you any relief from this issue. The solder flows into the via, leeching away from the desired solderpoint, after the solder has become liquious. The chemical make-up of the solder contr
