More on Ground Planes

F.Hart (fghart@mmm.com)
Fri, 26 Jul 1996 16:34:21 -0500

Thanks to everyone who responded to my initial question. Here's more
info on what I meant by ground plane discontinuity:

1. The edge of the microstrip ground plane runs parallel to (and directly
below) the edge of the first conductor.
_________ _________
________|_______|_______|_______|___________ Conductors
|___________________________________________| Dielectric
|___________________________________| Ground

2. The discontinuity is random (ie. a conductor passing over a via/solder
ball well in the ground plane).

3. The discontinuity is regular (ground plane mesh).

4. The ground plane stops at some length short of the end of the microstrip
(ie extra long leads/tails).

(I'll deal with voltage disparaties some other day).

It has been my experience that most solvers idealize the ground plane. I'm
just doing a reality check based on simplified problems which represent
real situations. Hopefully this may develop into a technical paper.

Frank Yuan: you mentioned several papers which are not yet published, but
sound very helpful. Specifically, references 5 (for a different problem I'm
working on) & 6 should be very interesting. Is it possible you could Fax a
copy to me? I would greatly appreciate it.

Thank you again, to all. And keep that good input flowing! Have a great
weekend.

____________________________________________________________________
|__________________________________________________________________|
|| || ||
|| Frances G. Hart || e-mail: fghart@mmm.com ||
|| 3M || ||
|| Austin, Texas || Phone: (512)984-6869 ||
||______________________________||__FAX:_____(512)984-5940________||
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