Subject: Re: Bird 36.2

From: [email-masked] ( Bob Ross)
Date: Wed, 12 Mar 97 09:38 PST

David:

Here are some responses which add on to Stephen's responses.

When you need details concerning vias and test pads, you most likely need the
physical database itself.  The electrical data base of BIRD36.2 could also
approximate some of these effects with appropriate IBIS terminator models
for capacitance, etc.

It looks like you may need several board models for board tolerance 
information.  The IBIS models can have the Component tolerance 
information.

In general, the electrical board description fills an area where the
physical description is not available for an existing board, or where 
the board has not been physically designed.  So the electrical board
description may lack some detail.

Best Regard,
Bob Ross
Interconnectix

> To: [email-masked]
> Date: Mon, 10 Mar 1997 13:24:22 -0800 (PST)
> From: "David Fogel" <[email-masked]>

> Questions regarding  Bird 36.2,

> 1. How do you specify vias (thru or blind) or pads that add additional 
> capacitance to a trace, like test pads?

> 2. How do you specify tolerances for all the parameters in Bird 36.2?
> Nominal values may not be sufficient for doing a thorough SI analysis.

> David Fogel