Re: [SI-LIST] : Plane Capacitance

About this list Date view Thread view Subject view Author view

From: Joel Jorgenson (joeljorg@prairie.NoDak.edu)
Date: Thu Nov 11 1999 - 07:11:20 PST


I've designed a number of six layer circuit
cards that had the planes on layers 2 and 5.
This created two layers of stripline circuitry,
although it decreased the innerplane capacitance.

The circuit cards could then be designed such
that all signal layers (1, 3, 4, and 6) have approximately
equal characteristic impedances.

If I kept the design to six layers, but placed the planes
as close as possible (layers 3 and 4), I would sacrifice
the stripline construction as well as matched impedances
between layers.

I wasn't worried about "too much" capacitance, but rather
I worried if I had "enough" capacitance. In my case, separating
the planes still provided enough capacitance.

Joel Jorgenson

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


About this list Date view Thread view Subject view Author view

This archive was generated by hypermail 2b29 : Tue Feb 29 2000 - 11:39:45 PST