Electronics Forum | Tue Mar 22 11:20:56 EDT 2011 | jercole
NEED HELP!!! I am getting solder splatters on my panels. We produce 100's of different kinds of product and this is the only one that is leaving solder splatters all over the masking. It is however the first time we have used 40 pin QFN's. I don't th
Electronics Forum | Tue Jul 24 07:57:55 EDT 2007 | davef
It sounds like the QFN component is not solderable. * Use ANSI/J-STD-002, Solderability Tests for Component Leads, Terminations, Lugs, Terminals, and Wires * Contact your QFN component supplier for help * Consider a more active flux, since you might
Electronics Forum | Fri Jul 27 15:51:29 EDT 2007 | hussman
Well I agree with jdumont in the fact that you should reduce the center pad at least 50%. Generally the sides of the leaded ends are not plated and solder will not wick up. This means only the bottoms of the leads wil solder. Look in this area whe
Electronics Forum | Thu Jul 26 23:43:49 EDT 2007 | gioblast
check your stencil design on the ground pad. You might have a big aperture opening that pushing the component away from the paste. Look alos the way your pcb warp. Prioritize side that has component that need flat pcb as much as possible. hope this h
Electronics Forum | Fri Jul 27 12:13:57 EDT 2007 | jdumont
We have issues with these also. They need to be flat to solder well. Reduce the square under the part for the heat sink and youll improve yields. That pad keeps the part lifted high while the other smaller joints reflow and partially attach. You can
Electronics Forum | Fri Jul 27 08:49:35 EDT 2007 | cman
We are currently have failures on one of our QFN > components. We are running this product with > lead free paste, lead free boards and lead free > parts. They have done a pull test on this > component and it showed that the solder joint > mai
Electronics Forum | Tue Jul 24 07:15:16 EDT 2007 | james
We are currently have failures on one of our QFN components. We are running this product with lead free paste, lead free boards and lead free parts. They have done a pull test on this component and it showed that the solder joint mainly dissconnect
Electronics Forum | Tue Jun 07 08:31:57 EDT 2011 | bootstrap
I am building a rugged digital video camera product that essentially is just a sandwitch of 3 parts: #1: front piece is machined aluminum with C-mount thread #2: middle piece is 1/16" printed circuit board #3: back piece is machined aluminum The
Electronics Forum | Thu Aug 24 06:58:19 EDT 2006 | davef
Darby National published stencil recommendations for their LGA in the "SMT Assembly Recommendations" section of: http://www.national.com/an/AN/AN-1187.pdf Is it possible that Silicon Laboratories published a similar document for your Cygnal CP2101?
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.....
