Electronics Forum | Thu Oct 27 12:58:33 EDT 2005 | gregp
EIA-481-B Max tape thickness 1.1mm (not including bottom and top cover tapes which can be .1mm max each) Of course a 1.1mm thick piece of steel will be stiffer than a 1.1mm thick lasagna noodle (already cooked). Is the thickness the issue or is it t
Electronics Forum | Wed Oct 26 10:21:28 EDT 2005 | russ
We are also experiencing problems with this thick stiff paper tape. Our problem is the strength of the spring that supports the tape at its pick position. After a while it just pushes it down because the tape exit wants to bend the tape too sharply
Electronics Forum | Thu Oct 27 09:23:36 EDT 2005 | rlackey
Hi Russ, Kemet - http://www.kemet.com/kemet/web/homepage/kechome.nsf/vapubfilesname/F3102CE.pdf/$file/F3102CE.pdf You want page 29 of 30 of this PDF Murata - http://www.murata.com/catalog/c02e11.pdf Page 132 of the catalog, or 134 of the PDF.
Electronics Forum | Thu Jan 19 09:41:47 EST 2012 | charliedci
We have the same issues with QFN's on reels being cost prohibitive, so we also have to deal with tubes. We have had some luck with using a modified tube ran down (almost to the pick position) the channel of a belt feeder, assuming the QFN tube/channe
Electronics Forum | Thu Jan 12 11:41:02 EST 2012 | babe7362000
We are recieving many QFN's in Tubes instead of trays and tape. Does anyone have luck with these in a tube feeder, or vib plate? We cant justify to order a full reel because the cost of the part.
Electronics Forum | Fri May 22 08:04:30 EDT 2009 | stevezeva
Have any of you ever worked with Actel's QFN 180? A three row I/O QFN? Actel has a published paper on design and assembly guidelines, but we're finding that they are pretty much generic, and don't really work as well as they lead you to believe. ht
Electronics Forum | Tue Jun 25 01:24:25 EDT 2019 | sssamw
That is possibley CTE mismatch between QFN and PCB material, the thicker PCB the higher fail rate.
Electronics Forum | Wed May 20 17:00:56 EDT 2009 | dyoungquist
We just placed a 56 pin QFN, 1 per board, on 10 boards and had zero defects. A good paste job, proper placement and a correct oven profile are the keys. If these are set up correctly, on larger runs your defects won't be zero but they should be le
Electronics Forum | Wed May 20 17:18:09 EDT 2009 | daxman
Just out of curiosity, how are you or anyone else determining a defect? Last I checked, IPC had no criteria yet for solder defects for QFN components. Has this changed? Biggest problems we see are voids which our x-ray shows a lot of. Our problems
Electronics Forum | Tue May 12 10:03:12 EDT 2009 | daan_terstegge
Hi All, I see more and more components like QFN or LGA with bottom-only terminations,with landpatterns getting finer all the time. I have no ppm-figures of our process, but based on a benchmark study by Agilent I'd say that 500 ppm is a decent value
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