Mail*Link(r) SMTP               FWD>DES & FAB Large Conductive Areas

Kenny -- if at all possible break them up, don't let you designers get away
with it.  Generally with most packaging densities there are enough holes and
openings in the planes to break up the large areas of solid Cu.  We do some
designs with wide, 70 micrometer (2 oz/sqft) Cu, internal, high-current
conductors at assembly.  We've had one that failed due to power cycling
(operating).  Yes design it right -- break them up.

Ralph Hersey
Lawrence Livermore National Laboratory
e-mail: [log in to unmask]

--------------------------------------
Date: 3/29/96 4:35 PM
From: Kenny Bloomquist
We are struggling with the interpretation of IPC-D-275 paragraph 5.3.1.5.
One group is arguing that this paragraph discussing cross-hatched areas only
applies to external layers and the other group feels that it should apply to
all layers.

What say gang?


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Date: Fri, 29 Mar 1996 11:43:19 -0800
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From: [log in to unmask] (Kenny Bloomquist)
Subject: Large Conductive Areas
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