RE: [SI-LIST] : Return path for stripline, two ground planes or one power and one ground?

About this list Date view Thread view Subject view Author view

From: Dan Swanson (dswanson@bartleyrf.com)
Date: Fri Mar 31 2000 - 04:38:43 PST


Francis,

I believe a true stripline mode must have equal return currents
in both planes.

You can set up a simple experiment on a field-solver. Build
a microstrip to stripline transition and look at the currents in
the ground planes. With no vias connecting the ground planes,
the currents are clearly not balanced. You also launch a parallel
plate waveguide mode at the transitions.

If you put several gnd vias around the signal via and connect the
two planes together, the ground plane currents are balanced and
the parallel plate mode is greatly reduced.

You have to be carefull how you set this up in some field-solvers,
if you allow currents to flow in the box walls of the simulator, it
can mask some of these effects.

Dan

Dan Swanson EMAIL: d.swanson@ieee.org
Bartley R.F. Systems TEL: (978) 241-1091
38 Water Street FAX: (978) 388-7077
Amesbury, MA 01913

-----Original Message-----
From: =?BIG5?B?Sm9obiBMaW4gKKpMtMK31yk=?= [SMTP:John@quantatw.com]
Sent: Thursday, March 30, 2000 8:00 PM
To: si-list@silab.eng.sun.com
Cc: 'Kai, Francis'
Subject: [SI-LIST] : Return path for stripline, two ground planes or one power and one ground?

 << File: ATT00002.txt; charset = BIG5 >> << File: ATT00003.html; charset = BIG5 >>

**** To unsubscribe from si-list or si-list-digest: send e-mail to majordomo@silab.eng.sun.com. In the BODY of message put: UNSUBSCRIBE si-list or UNSUBSCRIBE si-list-digest, for more help, put HELP.
si-list archives are accessible at http://www.qsl.net/wb6tpu
****


About this list Date view Thread view Subject view Author view

This archive was generated by hypermail 2b29 : Thu Apr 20 2000 - 11:35:58 PDT