Electronics Forum | Fri May 01 06:49:31 EDT 2009 | davef
minimum space between selective wave soldering pallet's opening to the nearest PTH or SMT pad? * http://www.agicorp.com/pdf_files/Designguidelines903.pdf * http://www.datumdynamics.com/resources/dfm_wavesolder.html?PHPSESSID=a73b3bc8bbd55519bffbb68
Electronics Forum | Thu Apr 30 02:39:48 EDT 2009 | michafogel
Thanks for the info so far, but still need a number or a formula to calculate. The site you have point me to can support in a way, but if I want to release a design procedure to our editors, a number will be very helpful. One more issue is what can b
Electronics Forum | Wed Apr 29 04:57:08 EDT 2009 | davepick
It depends on the application what will be considered the biggest issue to avoid (production or longterm reliability). Tin Whiskers are bit of an unknown quantity - but a more realistic problem could be dendritic growth / electromigration forming sho
Electronics Forum | Tue Apr 28 04:07:56 EDT 2009 | davepick
There's a nice tool on this site - http://www.enhancetechnical.co.uk/ Click on Internet Tools and then the image - brings up a useful interactive tools which helps understand influences on wave solder bridges. Dave
Electronics Forum | Tue Apr 28 07:45:07 EDT 2009 | davef
When using high tin solder, doesn't proper specing to avoid the effects of tin whiskers become at least as large an issue as proper specing for defect-free wave solder processing?
Electronics Forum | Thu Apr 30 05:54:41 EDT 2009 | davepick
Michael, There are so many factors involved that mean a definitive number is extremely difficult - if not possible. I recommend you speak with Tony Wilson. He has been in the industry for over 25 years and reccently done PhD work on modeling failure
Electronics Forum | Fri Aug 24 14:15:24 EDT 2007 | clarkk
Ben, I'm not aware of any 'automatic' method to convert PTH footprints to SMT. Typically, many of the components are passives, and there may be a way in your CAD software to change the passives of a common size to a different footprint. That will co
Electronics Forum | Tue Jun 14 15:03:15 EDT 2005 | slthomas
In that the machine times out and waits for a feeder refill and doesn't just skip that part and leave the space empty, it's not a defect. I have found 500ppm *fairly* easily attained in SMT depending on the board mix and how you define (1) a defect,
Electronics Forum | Thu Sep 16 20:55:35 EDT 1999 | Dave F
| | We have some SMT components with gold plated leads. They're actually LCC led packages. A good solder alloy to use would be Indium / Lead to reduce tin dissolution into the gold and avoid the resultant brittle intermetallic compound. However, a re
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