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IBIS Models Support in Eldo
Introduction to IBIS
Introduction to IBIS
I/O Buffer Information Specification (IBIS) is an ANSI/EIA-656 standard that is developing a
specified industry standard method to electronically transport input/output buffers modeling
data between semiconductor vendors, EDA tool vendors and end customers.
Eldo supports IBIS version 5.0.
IBIS Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 728
Using IBIS Models in Eldo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 728
IBIS Resources on the Web. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 729
IBIS File Types and Structures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 729
Checking IBIS Files with the Golden Parser. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 731
IBIS Background
IBIS was originally developed by Intel ® Corporation in the early 1990s. With the participation
of more companies and industry members, IBIS Open Forum was created to promote the IBIS
development and to make sure that standard exists. In 1995 the IBIS Open Forum teamed with
the EIA. Since then the EIA/IBIS Open Forum oversaw all technical developments of IBIS.
The IBIS committee provides a new version every one or two years. Each version adds more
features that the EDA tool vendors should support, and describes how the related input data is
formatted. The latest IBIS standard is IBIS version 5.0 which was ratified by the EIA IBIS Open
Forum on August 29, 2008. The previous standard, IBIS version 4.2, was ratified by the EIA
IBIS Open Forum on June 2, 2006 and formally ratified as ANSI/EIA-656-B on September 1,
2006.
IBIS is a behavioral model that describes the electrical characteristics of the I/O buffers using
V/I and V/T tables. It has the advantage of not showing any proprietary information. Moreover,
the use of behavioral simulation, instead of transistor level simulation, helps in accelerating the
signal integrity analysis and the overall design cycle. It is important to note that IBIS does not
provide the models themselves but describes how the input data to the EDA tool is formatted.
An IBIS file contains data not only about individual buffers but also about an entire component
(IC) including pin-to-buffer mapping and package parasitics.
Related Topics
Using IBIS Models in Eldo
Using IBIS Models in Eldo
Using IBIS in Eldo is similar to using other SPICE elements, such as transistors. You specify a
name for the buffer, the nodes to which the buffer is connected to the rest of the circuit, and
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Eldo® User's Manual, 15.3