Electronics Forum | Tue Mar 14 12:22:20 EDT 2017 | pzappella
Hello, I was at a IMAPS conference last year 2016 and several presentations for QFN packages showed x ray images with high void levels of 30 to 50% with the best around 15% with solder paste. During the discussion it was mentioned that the auto in
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 | Thu May 08 19:52:40 EDT 2014 | hegemon
There are many different style LGA packages, but don't sweat it. Stick with the manufacturers recommendations for PWB pad geometry for a start. Voiding can be reduced by careful profiling, and also by pre-tinning the devices. QFN style packages can b
Electronics Forum | Wed Mar 02 05:01:41 EST 2005 | ABHI
Are your packages mounted on boar using sockets or BGA balls? LGA's are usually no issue and are simple compared to BGA. No issue on missing balls or ball drop issues. However, LGA's need quite a bit of mounting / holding pressures during test and mo
Electronics Forum | Wed Jul 30 11:41:06 EDT 2014 | emeto
example
Electronics Forum | Wed Jul 30 00:47:10 EDT 2014 | matusov
Hello gurus, I am a hardware designer with a small company. We are about to send a new PCB for fabrication. This board uses dozens of tiny QFN, DFN, and similar packages. As a final check I have been going through the datasheets of all these parts t
Electronics Forum | Wed Jul 06 06:17:11 EDT 2016 | pavel_murtishev
Dear members, Recently we have found that solder mask thickness variation could lead to solder balling under QFN packages for a high reliability device. Is there any industry proven method for solder mask thickness checking? Any equipment or any me
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 | Sun Aug 27 01:05:37 EDT 2006 | PP
Paul, 1. What Kind of IR System you use? 2. With QFN, LLP packages, how do you apply solder paste for rework? Thanks for your answers PP
Electronics Forum | Thu Aug 08 10:58:18 EDT 2002 | Tom Gervascio
I'm interested in sharing any information on bumping of LAnd Grid Array (i.e. QFN) packages. due to PCB contraints, it's not possible to stencil paste onto sites for QFNs. That lead to a lot of experimentation with bumping of 6 mm QFN packages.In sum
