Subject: How to do correlation with two extra Rising/Falling waveforms?

From: John Lin - TAO <[email-masked]>
Date: Thu, 9 Apr 1998 09:08:01 +0800

Hi IBIS fans,

In the IBIS Forum's I/O BUFFER MODELING COOKBOOK, page 12, there is a 
table - "Recommended Load Circuits and Waveforms for V/T Data 
Extraction."

In the table, there are 4 waveforms to extract V/T data for [Rising 
Waveform] and [Falling Waveform] for a standard push/pull CMOS type 
buffer.

I/O buffer+ R-fixture+V_fixture.

For falling edge, two waveforms are obtained based on
(1)	V_fixture=0, and
(2)	V_fixture=VCC.

For rising edge, two waveforms are gathered based on
(3)	V_fixture=0, and
(4)	V_fixture=VCC.

The cookbook uses (2) and (3) to extract data in [Ramp] and says (1) 
and (4) are for correlation.

How is the correlation done?
 What information can be extracted from (1) and (4)?

Inside the Quad Design XTK manual, the (1) and (4) can be used to 
generate Ground
Bounce Model.  How?

Any inputs from you are appreciated.

Thanks,

JOHNLIN
CAE Engineer of EDA Department
Digital Equipment Corp. Taiwan Branch
Email: [email-masked]
TEL: 1-886-3-3900000 ext. 2152