Electronics Forum | Mon Oct 02 19:04:53 EDT 2006 | DC
We had a issue on the SBGA and found stress built up at the corner of the SBGA after cool down to room temperature. It is confirmed by the warpage analysis. I expected that the stress caused by the heat spreader and the epoxy to the copper frame. O
Electronics Forum | Mon Mar 21 02:41:29 EDT 2011 | kemasta
Hi It's me again. Our products need to pass a chamber test 45c/36hrs after the PCBA completed batch of functional tests and assemble in to case. We found 1 unit was functioning for 24hours in the chamber, but hang after that. We tried to re-boot the
Electronics Forum | Thu Jan 08 10:56:13 EST 2009 | aj
Hi, Is there any PTH Assembly after reflow, we found cracked joints on some BGAs which was caused by operators ing Oupin connectors which were a tight fit. This caused the PCB to flex hence cracking joints. One way of checking for this during test
Electronics Forum | Wed Jan 07 00:18:14 EST 2009 | milanrit
Recently on one of my assemblies(sn/pb) I started seeing leaded BGA failure at functinal test for opens, but when I inspected them through 5DX and ERSA Scope it doesnt seem like there is any opens or insufficient and half no. of boards passed functio
Electronics Forum | Wed Sep 12 18:11:03 EDT 2001 | davef
First, what on the area array package are you analyzing � * Package cracking? * Cracked solder balls? * Er, what? Second, most failure analysis discussions consider dye penetration to be a non-destructive test, but then again most failure analysis
Electronics Forum | Wed Nov 01 13:44:50 EST 2000 | Thomas Ballhausen
Using convection type reflow we observed following problem: One ball of a 313-PBGA appears to be dewetting. This happens randomly, i.e. no specific ball location, failure rate is rather low (3-4%), but since there are 12 PBGAs on one board the failu
Electronics Forum | Mon Aug 14 08:18:24 EDT 2006 | John N.
Hi all, I work for a service company who do SMT repairs for a Blue Chip. The JEDEC standard doesn't seem to mention how long (if at all) you should bake a planar after placing a new BGA (after field failure). Any ideas? Thanks in advance. regards Joh
Electronics Forum | Wed May 04 22:04:55 EDT 2005 | davef
First, you cannot determine if this is "black pad" by looking at it. You must do laboratory analysis, either microsectioning or EDS. [But it sure sounds like "black pad."] Second, if it is black pad, it was created by the company that fabricated t
Electronics Forum | Wed Jan 17 03:35:07 EST 2001 | Arul
We have few failures similar to the discussion in this thread, on a 50 Mil pitch, 30 Mil mill Ball PBGA. Would like to understand the mechanism of the BGA reflow process bit more. Appreciate your response to the following. 1.We sheared few solder ba
Electronics Forum | Fri Apr 29 14:16:16 EDT 2011 | ppcbs
Below is the long explanation. This defect is most commonly found with BGA components, but can arrise with all components. I see it happening more now with lead free boards that are being assembled with a no clean flux. Best short term remedy is t
