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Submitted by: steeletraps on 2005-05-23 22:58:54.
Topic:Re: IBIS Model Library
Body:One thing to remember about the IBIS model is that they only model the I/O buffer specifications. They don't model the internal logic of the device.
The simulator I use has an IBIS translator, but I haven't had need to use it. If it helps, they have an article on it at: http://www.spectrum-soft.com/news/fall2004/ibis.shtm This may give you an idea of how effective they are, and if this even applies to what you are looking to do.
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Submitted by: webmaster on 2005-04-22 11:08:57.
Topic:Re: IBIS Model Library
Body:Hi Mick,

here is the history background regarding the IBIS models I've found on the "Practical Issues with IBIS Models" page located: http://www.eigroup.org/ibis/pcbeas97.htm.

This should answer your questions.

In the early 1990s, Intel Corporation initiated internally a Lotus spread-sheet table-based model while attempting to convey the stringent requirements of PCI bus drivers and provide a common format between divisions for external communication. Several vendor specific formats did exist at that time. Because data preparation and model availability had been primary issues, Intel invited EDA vendors to join forces and define a common model format. IBIS Version 1.0 was issued in June 1993 and a clarification update Version 1.1 in August 1993. The IBIS Open Forum dedicated to keeping abreast with technical needs and promoting the availability of IBIS models also was born.

IBIS Version 1.1 was introduced with the understanding that it would be expanded in an upward compatible manner. More EDA vendors, semiconductor vendors and users joined the IBIS Open Forum, and through their cooperative efforts IBIS Version 2.0 was presented June, 1994 with many technical extensions. In February 1995, the IBIS Open Forum formally affiliated with the Electronic Industries Alliance (EIA). With some minor technical and textual clarifications and through formal letter ballot review processes, IBIS Version 2.1 was issued and became an official American National Standard Institute standard ANSI/EIA-656 in December 1995. Version 2.1 has remained until now as the next stable level of functionality.

The EIA IBIS Open Forum has continued meeting regularly for additional technical extensions. It has also been working on all aspects of promoting IBIS models, utilities and information. As a result the EIA IBIS Open Forum maintains an abundance of information, articles and helpful documents on the official EIA IBIS home page. Over 13 semiconductor vendors offer IBIS models directly and several commercial IBIS model vendors have up to 10, 000 components modeled. Spice to ibis, ibis_chk and IBIS plotting utilities have been developed for free availability. Several "IBIS Summit" meetings have been held to communicate new applications and ideas. The IBIS mailing lists are used to conduct business and also to provide a forum for questions and user issues. As a result of the collaboration of common interests, IBIS Version 3.0 has just been issued in June, 1997 to define the newest level of technical functionality.

Like Spice models, IBIS models are formatted in human-readable, ASCII text. However, IBIS models do not require proprietary information. The critical electrical characteristics are based on derivative information -- derived by simulation or measurement. Consequently, models of current devices are becoming more readily available in IBIS than in Spice formats.

Spice models tend to be buffer centric; the model often represents one of several inputs or outputs of a buffer. IBIS models are component centric; the model describes all pins of the physical component. Physical databases used for large board designs provide suitable component footprint interfaces, ideal for the insertion of IBIS component models. Thus, EDA vendors support IBIS to integrate electrical components with physical data describing thousands of nets.

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Submitted by: Mick_Lovell on 2005-04-20 12:31:51.
Topic:IBIS Model Library
Body:Dear About Spice.
  1. What has driven the need for IBIS models?
  2. Are they relevant for power electronics simulation or is a Spice simulation adequate.
  3. How effective is the Spice to Ibis conversion?

Thanks for a good site.
mick lovell

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