Electronics Forum | Tue Mar 01 15:13:22 EST 2011 | felixgutierrez
Hi Everyone. I would like your input in regards to lead free solder paste lead free. Which one is the most reliable solder for BGA's and BTC's (QFN). I have used different type of solder and on some of them i get big voids on BTC's and other one i g
Electronics Forum | Tue Sep 23 14:13:29 EDT 2008 | slthomas
In piggy back on Chunks' comments, what you might wipe it with can be the problem. Alcohol absorbed by the solder paste inhibits the effectiveness of some cleaning chemistries, and driving it into the nooks and crannies exacerbates the problem. If
Electronics Forum | Thu May 26 08:52:42 EDT 2011 | davef
Phil Zarrow wrote a useful paper that could help in evaluating paste. Here read it ... Evaluating Solder Paste � Not An Option Contributed by Phil Zarrow of ITM an Independent SMT consulting firm With soldering being the dominant source of assembly
Electronics Forum | Fri Jul 15 13:58:32 EDT 2005 | seaK
Our production is putting QFN40 and QFN56 package on board. With 80% opening on terminal, 40% on thermal pad, we found QFN56 100% forming toe fillet, but it does not work out the same to QFN40. We suspect it's because of the weight of component.....
Electronics Forum | Fri Jul 08 16:35:04 EDT 2005 | Jason Fullerton
"Whether or not you need a toe fillet depends on your application. We have high reliability products where we can't use a QFN over a certain size, regardless of toe fillet. We have other applications where we meet the thermal cycle requirements for a
Electronics Forum | Wed Jul 06 14:36:05 EDT 2005 | Bob R.
The only way we can consistently get a toe fillet is to use a paste with an extremely active flux. We allow that paste on certain products, but discourage it's use because it's on the hairy edge of not meeting our lower limit in surface insulation r
Electronics Forum | Thu Jul 14 09:42:36 EDT 2005 | saragorcos
Our facility helps customers clean no-clean soldered boards on a regular basis, and it definitely can be done but is a little more challenging than boards built with water soluble flux - one piece of advice I would give is to use low water pressure (
Electronics Forum | Tue May 07 10:36:38 EDT 2019 | slthomas
Probably just means you started out with an optimal profile. I suspect that not everyone does. ;) It seems like we did have some luck with profile adjustments in one instance with some QFN's with a large thermal pad. Like I said, though, the profi
Electronics Forum | Wed Nov 17 11:20:23 EST 1999 | Dave F
Hey Gyver: If you don�t mind (which you don�t have any choice about, because I�m going to do it anyhow, cause it�s MY word processor), I�m going to respond genericly, but still be directed to your question. Much of the following is paraphrased from
Electronics Forum | Mon Jun 12 07:42:56 EDT 2006 | brian.perry@suntroncorp.com
We are placing a gold plated device (LCC) to a NiAu PCB using a SnPb No-clean solder. We're noticing quite a bit of difficulty with reliable joints (intermittent connectivity) and if we have to rework a particular device, adjacent devices of this sa
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