Extracting coupled nets to SigXP

Hi Drew,

The secret explained in that appnote was to get PCB SI to do the simulation you want and grab the interconn.spc file and stuff it into an Espice Black Box model for sigxp.  While that sounds simple enough, the bulk of the difficulty lies in getting the correct data from ntl_rlgc.inc also into the black box in the correct way.  It's do-able once you understand the technique explained in the appnote.

There were actually a couple appnotes that explained this.  I'll browse the site to see if I can locate where it is now and will post the link if I find it.

One caveat though.  Note that you won't be able to easily "what if" the interconnect crosstalk in the black box, but only whatever else you might draw around it.

Hope that helps,
Donald

Found it under Articles->Modeling.  Here's the description:

Describes a method for creating a black box model (DML) for three coupled differential pair. Using signal probe within Allegro PCB SI makes it possible to extract single-ended nets and differential nets into Sig-Xp. This document describes a method for creating a black box model (DML) for three differential pairs that are coupled to one another. This black box model can then be placed and used within Sig-Xp just as any other component. The same basic method used for this particular example could be used to create a black box model for any arbitrarily routed interconnect.


Donald

Thanks, Donald, that's what I was looking for.

-Drew