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id m0vG53X-0000SuC; Wed, 23 Oct 96 10:17 CDT |
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| From [log in to unmask] Wed Oct 23 17: |
03:02 1996 |
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This is a good idea. Especially if you have high speed signals running
near the board edge. The only problem I see is where you say to "...tie
the external planes and the internal ground plane together..." I think
you probably meant to say "...tie the external planes and the internal
GUARD RINGS together..." This prevents any possibility of the shield
becoming a part of the return path.
Don Walker
[log in to unmask]
> to run a guard ring of ground around the periphery of the board on all
> layers and tie the external planes and the internal ground plane
> together through closely spaced (.25 inch) vias only at the guard
> ring.
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