Electronics Forum | Mon Apr 27 02:44:07 EDT 2009 | michafogel
Can someone point me to a standard, if there is any, or design rule regards with preffared spacing between PTH and SMT pads for LF wave soldering process (SAC alloy)
Electronics Forum | Thu Apr 30 06:14:26 EDT 2009 | michafogel
Thanks , I'll try it too.
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 | Thu Apr 30 22:40:32 EDT 2009 | davef
Selective Wave Soldering DoE to Develop DfM Guidelines for Lead and Pb-Free Assemblies Written by Makram Boulos, Craig Hamilton, Mario Moreno, Ramon Mendez, German Soto and Jessica Herrera Circuits Assembly Magazine, 31 December 2008 19:00
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 | 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 | 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 | Wed Sep 25 13:38:35 EDT 2002 | finepitch
Yannick, If we leave the 201 issue aside; have you checked where those BGA pads are connected to? Could those be power/ground balls connected to large (difficult to heat up) planes by any chance? Erhan
