Subject: Commnets on IBIS FAQ - Reply

From: Hsin-Huei Lin <[email-masked]>
Date: Tue, 08 Aug 1995 13:36:38 -0500

Hi,
	I have one question about item 1 below. I always think IBIS is
the modeling format for Digital devices only, but the following statement
did not call out Digital specifically. Does that mean I can use IBIS to
model discrete component like Res, Cap, Diode and Analog component like
opamp? If this is correct then which part of the IBIS definition address
these?

Hsin-Huei Lin
Medtronic, Inc.

>>> Raj Raghuram <[email-masked]> 08/07 4:46 pm >>>

1. Item 1 mentions that IBIS "can be used to model almost 99% of all 
   semiconductor". I think  we could just make it "most semiconductors".

---

From: [email-masked] (Raj Raghuram)
Date: Tue, 8 Aug 1995 13:48:41 -0700

This is in response to your question on the use of IBIS as a modeling format 
for Analog Devices. My immediate thoughts on this are given below. I am sure
you will get other responses as well.

IBIS evolved from the need to describe Digtial Drivers and Receivers without
having to give away proprietary transistor level models and circuits. But the
general principles should apply to all devices. The package information is
relevant (for example) even for a simple 2-terminal capacitor. There is 
definitely a need to model opamps for use in Signal Integrity simulations. 
Crosstalk from a "digital" line (or trace or pin) onto an analog line is often
of great concern. 

It may be possible to model certain opamps in the IBIS format even now. The 
input would be differential (Version 2.1 format may be necessary). The output
does have the protection diodes and could be described by a Output type model
format. However, other functional attributes of an opamp would not be modeled.
IBIS is not intended for a functional simulation in any case. Certain
other opamps may require a new model type (i.e such as Input, Output, I/O, or
tristate) not already defined in IBIS. 

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>> Included message
Hi,

Hsin-Huei Lin
Medtronic, Inc.