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| From [log in to unmask] Sat Apr 27 15: |
01:41 1996 |
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Background:
We had a PWA fail in the field after approximately 6-7 months. The unit
was powered on approximately 1000-2000 hours. Analysis of the PWA
revealed a short had developed between two parallel traces underneath an
IC. The traces are .006" wide and .010" apart. The short was not visible
(even under a microscope). The short was approximately 2 1/2 ohms in
value. Once a razor was run between the traces the short was eliminated
and the PWA was functional once again.
Someone I spoke to at a PWB Fabricator suggested it might have been
dendritic growth.
Questions:
What is dendritic growth?
Does causes it on a PWA?
Where can I get more information about it?
Can it be attributed to the PWB fabrication?
Any and all assistance is GREATLY APPRECIATED!
Best Regards,
Mark Lettang
3M
[log in to unmask]
(507)359-0418
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