At 12:28 AM 10/19/2007, Don Wilhelm wrote...
The 'tin-whiskers' problem is one that exists mainly at the chip
level.
The migration of conductive paths between pins that can be soldered by
hand techniques is *not* a problem because the 'whiskers' typically do
not extend that far. It is a problem inside the chips where distances
are measured in angstroms rather than in fractional inches or
millimeters.
Not according to NASA studies. They state "Whiskers as long as a few
millimeters are not uncommon..." -
http://nepp.nasa.gov/whisker/background/index.htm
Common through hole IC packages (DIP) have 2.54mm center to center,
which means ~1 mm air gap between pins, and that is also a _very_
common hole spacing pattern for discrete components. Here's an example
of non-"chip level" failure caused by tin whiskers:
http://nepp.nasa.gov/whisker/photos/pom/2004april.htm
_______________________________________________
Elecraft mailing list
Post to: Elecraft@mailman.qth.net
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com
