Subject: IBIS MINUTES 5/5/00

From: Bob Ross <[email-masked]>
Date: Tue, 09 May 2000 13:51:00 -0700

SUBJECT: 5/05/00 EIA IBIS Open Forum Meeting Minutes

VOTING MEMBERS AND 2000 PARTICIPANTS LIST:
3Com                           Roy Leventhal
Agilent (EEsof, etc.)          Mark Chang
  Hewlett Packard              Paul Gregory
Applied Simulation Technology  Raj Raghuram*, Norio Matsui, Fred Ballesteri
Avanti                         Nikolai Bannov
Cadence Design                 Mike LaBonte*, Todd Westerhoff, Ian Dodd*,
                               Donald Telian, Patrick Dos Santos
Cisco Systems                  Syed Huq, Irfan Elahi, John Fisher
Compaq                         [Bob Haller], Peter LaFlamme, Ron Bellomio,
                               Shafier Rahman, Doug Burns
Cypress                        (Rajesh Manapat)
EMC Corporation                (Fabrizio Zanella),
Fairchild Semiconductor        Craig Klem
H.A.S. Electronics             (Haruny Said)
HyperLynx (& Pads Software)    Matthew Flora*, Kellee Crisafulli, Gene Garat,
                               John Angulo*, Al Davis, Lynne Green
IBM                            Michael Cohen, Greg Edlund*
Incases                        Werner Rissiek
Innoveda (Viewlogic Systems)   Chris Rokusek, Guy de Burgh*, Jun Tian,
                               Cary Mandel, Brad Griffin, (Jon Powell)
Intel Corporation              Stephen Peters*, Arpad Muranyi*, Will Hobbs,
                               Richard Mellitz
LSI Logic                      (Larry Barnes)
Mentor Graphics (& Veribest)   Bob Ross*, Tom Dagostino, Malcolm Ash,
                               Kim Owen, Jean Oudinot, Sherif Hammad,
                               Hazam Hegazy, Weston Beal
Mitsubishi                     Shahab Ahmed
Molex Incorporated             Gus Panella
Motorola                       Ron Werner
National Semiconductor         Milt Schwartz
North East Systems Associates  Edward Sayre, Tony Sinker
NEC                            (Hiroshi Matsumoto)
Nortel Networks                Steve Coe, Calvin Trowell*, Hassan Ali
Philips Semiconductor          D.C. Sessions*
  (& VLSI Technology)
Quantic EMC                    (Mike Ventham)
Siemens AG                     Bernhard Unger, Gerald Bannert
SiQual                         Scott McMorrow, Wis Macomson
Texas Instruments              Stephen Nolan*, Ramzi Ammar, Mac McCaughey,
                               Thomas Fisher, Jean-Claude Perrin,
                               Jean-Yves Oberle
Time Domain Analysis Systems   Dima Smolyansky, Steven Corey
Tyco Electronics (AMP)         (Russell Moser)
Via Technologies               (Weber Chuang)

OTHER PARTICIPANTS IN 2000:
Actel Corp.                    Silvia Montoya
Advansis                       Mikio Kiyono
Aerospatiale Matra CCR         Lionel Dreux, Julien Boullie
Alcatel (Lannion, Bell)        Daniel Peron, Steven Criel
Brocade Communications         Robert Badal
EIA                            Cecilia Fleming*
Fraunhofer Institute           Michael Kurten
Jet Propulsion Lab             John Treichlew
Rockwell Collins               Ron Hau
Signals & Systems Engineering  Tom Hawkins
ST Micorelectronics            Fabrice Boissiere, Pierre Saintot
Sun Microsystems               Victor Chang
Thomson-CSF                    Savenrio Lerose, Pascal Vaslin, Thierry Zak,
                               Sylvie Lasserre
Transfer                       Hans Klos, Wilco Hamhuis
Xilinx, Inc.                   Susan Wu

In the list above, attendees at the meeting are indicated by *. Principal
members or other active members who have not attended are in parentheses.
Participants who no longer are in the organization are in square brackets.

Upcoming Meetings:  The bridge numbers for future IBIS teleconferences are as
follows:

  Date                Bridge Number    Reservation #    Passcode
  May 26, 2000       (916) 356-9200   3-373074          77923642
  June 8, 2000 - DAC 2000 IBIS Summit Meeting (No Bridge)

All meetings are 8:00 AM to 9:55 AM Pacific Time.  We try to have agendas out
7 days before each Open Forum and meeting minutes out within 7 days after.
When you call into the meeting, ask for the IBIS Open Forum hosted by Will
Hobbs and give the reservation number and passcode.

NOTE: "AR" = Action Required.

-------------------------------- MINUTES -------------------------------------

INTRODUCTIONS AND MEETING QUORUM
No new participants.

MEMBERSHIP UPDATE AND TREASURER'S REPORT
Bob Ross reported that Tyco Electronics. (formerly AMP, Inc.) is now an EIA
IBIS Open Forum member.  We are still tracking renewals and will start
dropping members that have not renewed.  Currently we have about 29 paid
members this year.

REVIEW OF MINUTES AND AR'S
The April 14, 2000 IBIS Minutes were approved.

The AR's will be discussed during the meeting.

MISCELLANY/ANNOUNCEMENTS
None.

PRESS AND WEB PAGE UPDATES
Matthew Flora commented that Bob Haller could not find the subscribe
[email-masked] on our home page.  Mike LaBonte found it under the
Support link.  Matthew might still contact Syed Huq to make it clearer.

Mike LaBonte asked if we could have a search engine on our Home Page.
Cecilia Fleming stated that EIA could do this.  Bob Ross noted that a lot
information is contained in links to other sites, mostly eda.org.  Cecilia
stated that the search engine would probably not find the remote information.
However, she will check with her staff on this.

Bob R. reported that IBIS was mentioned in "Signal Integrity Analysis", by
Yorum Levy in the May 2000 issue of Printed Circuit Design, pp. 38 -45.

Bob R. also reported that several IBIS roster updates have been done.

NEW MODELS AVAILABLE, LIBRARY UPDATE
Bob Ross reported that some new Intel IBIS models have been posted at:

  http://developer.intel.com/design/celeron/devtools/
  http://developer.intel.com/design/PentiumIII/devtools/  (2 files)

OPENS FOR NEW ISSUES
Bob Ross - Differential Input Specification for Single-ended Input
D.C. Sessions - 100 Point Limit Issue

INTERNATIONAL/EXTERNAL PROGRESS
- IEC 62014-1 (IBIS Version 3.2) - Cecilia Fleming reported that IEC needs
a new document header information including Scope and process to create the
document.  She will draft the information and send it to Bob Ross for
review.  Bob will circulate it among the IBIS officers for review.

- pr EIAJ ED-5302 Standard for I/O Interface Model for Integrated Circuits
(IMIC) - Bob Ross had no further report.

- IEC PWI 93-1 Models of Integrated Circuits for EMI Behavioral Simulation
(formerly designated as IEC 93/67/NP IBIS and EMC Simulation) - Bob Ross
had no further report.  We are waiting for revised documents that we can
upload.

- JEDEC JC-16 - D.C. Sessions reported on recent JEDEC activity and hot topics.
One relates to whether device slew rate should be defined with or without
terminations.  Another related to how slew rate relates to flat regions in
the input response within the threshold regions.  Bob Ross commented that
BIRD62.6 got around this by defining a Tslew_ac and Tslewdiff_ac time bounded
by the corresponding *_ac limits.  D.C. stated that JEDEC does track how IBIS
deals with these issues.

D.C. stated that JEDEC is hold a meeting in Seattle, Washington that
conflicts with his attending the IBIS Summit Meeting.  D.C. also stated that
it would be helpful to the JEDEC members for EDA vendors to D.C. directly
their plans to support BIRD62.6.

Bob reported that Arpad Muranyi held a very successful IBIS training class
in San Jose, California on April 26, 2000.  It attracted about 180 people.
The following organizations served as co-sponsors:  Intel, Silicon Tech,
Transmeta, JEDEC and IBIS.  Class notes including lab exercises and a version
of IBISCenter for NT can be found at:

  http://www.eda.org/pub/ibis/training/

DAC 2000 IBIS SUMMIT MEETING
Bob Ross introduced the IBIS Summit Meeting by giving the basic information.
It is being held at the Hyatt Regency Hotel near some other hotels and about
six blocks from the Los Angeles Convention Center where the Design Automation
Conference (DAC 2000) is being held.  The IBIS Summit Meeting is scheduled on
Thursday, June 8, 2000 after the trade show portion of DAC 2000 (held Monday
through Wednesday, June 5-7).  The room is scheduled for all day.

The main topics will be election of IBIS officers for 2000 - 2001 and
probably some discussions on the Connector Specification and future IBIS
activities.

Related to IBIS futures several presentations are expected:

  Overview of XML - Mike LaBonte
  Macro Language - Al Davis (suggested by Matthew Flora)

D.C. Sessions asked for the agenda.  Bob responded that the agenda will not
be finalized until about a week or two before the meeting based on proposed
presentations.  The room is booked all day and we will plan to devote the
afternoon to IBIS futures and IBIS-X working group topics.  As in recent
meetings, substantial time will be devoted to interactive discussions.

Guy de Burgh plans to send out a second notice of the meeting. [Done]

ACCURACY HANDBOOK
Greg Edlund that the I/O Buffer Accuracy Handbook is now uploaded on

  http://www.eda.org/pub/ibis/accuracy/

It has more Spice related content.  Greg reported that is working on a test
board update and also with a semiconductor vendor apply the Handbook in an
actual accuracy study.  He expects results in several months and has obtained
permission to publish the results.

COOKBOOK STATUS
Stephen Peters had no report.

IBIS MODEL REVIEW COMMITTEE DISCUSSION
Matthew Flora reported that no new models have been received.

BIRD66 - [Model Spec] Vref ADDITION
Bob Ross deferred discussion on this topic.  We discussed it at the last
meeting, but have not acted further on it.  It may need a revised BIRD66.1.

IBISCHK3 BUG TRACKING
- BUG34 - No Error Reported for Missing V/I Tables in Output Buffers
Matthew Flora has not had time to issue changes that were discussed at the
the April 14, 2000 meeting to simplify some of the verbiage and to eliminate
a redundant test condition.  Discussion on BUG34 was deferred.

Bob Ross noted that new BUG reports have just been issued and need to be
classified.  They are based on problems reported previously on the IBIS
reflectors and on additional private discussions.  We use BUG reports to
formally address these problems and agree upon action.  The new batch of
BUG reports were sent to the smaller ibischk-bug reflector since they are
of a trivial nature.  They are stored under:

  http://www.eda.org/bugs/ibischk/

- BUG38 - Ver. 2.1 File Names Greater than 8 Characters Not Reported
Bob commented that Stephen Nolan originally reported this problem.  During
IBIS Version 3.25 parser development, the Version 2.1 level 8.3
<filename.ibs> test has been lost - perhaps through miscommunication.  This
should be restored because some IBIS Version 2.1 parsers are still being used,
and non-compliant IBIS Version 2.1 models are being passed by ibischk3.

BUG38 was classified as Moderate, Low, Open.

- BUG39 - No Warning is Given for Repeated Voltages in I-V Tables
Bob commented that Scott McMorrow and possibly others had reported a problem
based problems with actual IBIS models failing EDA vendor parsers.

Mike LaBonte stated that flat responses are supported in I-V tables.  Bob
clarified that the problem was not extrapolated points (with the same current
but different voltages), but repeated voltage points.

BUG39 was classified as Annoying, Low, Open

- BUG40 - Incorrect Error Message for Series Terminators
Bob reported that Jerry Hayes had reported this.  The problem was that
ibischk3 reported an error for a legal IBIS model when a Series element
such as [R Series] as used as a differential terminator for Input, I/O and
Output buffers.  Originally, the Series elements were planned for Terminator
models and NC models only.  We expanded the usage during the IBIS Version 3.2
development.  However, the ibischk3 parser code restrictions were not
updated.

The error report itself was misleading since it incorrectly stated that the
series model was wrong.

BUG40 was classified as Severe, High, and Open.

Bob noted that he also planned to issue a BUG41, but held off since he ran
into some interaction complications.  Instead, he is raising it as a new
issue (discussed later).

Bob will work with Atul Agarwal, Chris Rokusek, and Matthew Flora on doing
the fixes.  Already two other reported BUGs have been fixed, but the problems
were minor.  We are awaiting more fixes before issuing an ibischk3 upgrade.

CONNECTOR PROPOSAL REVIEW (CONTINUED)
Bob Ross summarized Working Group progress on the Connector Specification.
A meeting was held on Wednesday, May 5, 2000 with Bob, Kellee Chrisafulli
and Gus Panella.  We originally were going to discuss some suggestions on
documenting crossover pins (pin 1 connected to pin 2 and visa-versa) and
on some other internal details such as one input forking to two outputs and
several inputs necking down to an internal node and expanding to several
outputs.  We felt that as long as we know of possible solutions, we will not
try to introduce complications for the Version 1.0 release.

Bob also raised a more fundamental concern related to some perceived
inconsistency on what was required for the three modes.  In particular, he
did not understand the rationale for the stated Pin Map and Physical Map
requirements.  Bob defined these modes

  Physical mode with fixed connector pinout and corresponding matrix
  Physical mode with fixed connector pinout and a reduced Swath Matrix
  Autogenerated Mode with an automatically generated pinout and a Swath Matrix

Bob's concern is that BOTH the ModelPinMap and ModelPhyMap are required for
the first two cases.  Only the autogenerated equivalent ModelPinMap script
is required for the third case.  Bob questioned why ModelPhyMap is required
in the second case since it is really a fixed pin subset of the autogenerated
case.  This type of inconsistency needs to be understood further and
resolved.

Another Working Group meeting is scheduled on Monday, May 8, 2000 to discuss
this topic.

IBIS FUTURES (IBIS-X, API, BIRDxx)
Stephen Peters reported that a number of AR's are still outstanding.  He has
not had time to reconvene another Working Group meeting, but he would like
to hold another one before the IBIS Summit Meeting.

After some discussion Stephen plans to hold a meeting on Thursday, May 25,
2000, the day before the next IBIS teleconference meeting.  This may involve
both face-to-face and teleconference participation.  Stephen plans to set
this up.

Bob Ross mentioned again that we should plan for some discussions during
the IBIS Summit meeting on June 8, 2000.  There appears to be enough
content for D.C. Sessions to attend from Seattle.

BIRD61.1 - ENHANCED CHARACTERIZATION OF RECEIVERS
Bob Ross suggested that schedule a vote on BIRD61.1 with the intention to
reject it.  D.C. Sessions objected.  He argued that BIRD61.1 that its
solution is better than having no solution.

During the discussion, Stephen Peters noted that an IBIS-X approach using
some behavioral constructs presented at recent IBIS Summit meetings was
assumed to be a better approach.  Bob noted that BIRD61.1 allows too much
flexibility on supplied data.  Even if an EDA vendor could implement a good
algorithm, a set of legal, but insufficient data would likely bust the
algorithm.  Also, EDA vendors need to have a solid approach before making
the investment to implement a change.  It is not yet known what data should
be required and how much improvement will be obtained using this data.

D.C. stressed that an immediate solution is still required.  No alternative
has been proposed, so BIRD61.1 is still the best approach.  The DDR DRAM
devices currently exist and need to be modeled as soon as possible for
better timing margin simulation.

Mike LaBonte volunteered to work with D.C. Sessions to investigate further
the BIRD61.1 approach.  No vote will be scheduled yet on BIRD61.1.

BIRD64.1 - PACKAGE MODE SELECTOR
Not Discussed.

BIRD65 - C_comp REFINEMENTS
Bob Ross proposed opening discussion on BIRD65 at the next meeting.  Some
agreement had been reached that documenting extra parameters by direct values.
Bob proposed discussing this at the next meeting.  Arpad Muranyi, author of
BIRD65 stated that he felt BIRD65 was important.  However, he will be out
of town and miss the next meeting.  Arpad would like BIRD65 discussed at a
later time.

NEW TECHNOLOGIES
Bob Ross commented that the new technology discussion introduced at the
March 31, 2000 meeting by Michael Cohen and planned for the April 14, 2000
meeting was inadvertently not covered in that meeting.  Bob reported that
based on an off-line conversation with Michael, the topic dealt with
proprietary information that could not be discussed at IBIS meetings.

Bob opened another new technologies topic on modeling AVC technology devices.
The AVC technology is supported by approximately four vendors and is often
referred by different trade names.  However, the functional operation is
probably similar.  Normally the driver output impedance is designed to be
about 50 ohms to provide a good source impedance match.  However, during a
high-to-low transition, another 50 ohm pulldown driver is switched in for
extra strength and speed.  Similarly,  during a low-to-high transition,
another 50 ohm pullup driver is switched in.  These extra drivers are
triggered by a comparator that senses the output pin voltage.

Bob noted that he held off-line discussions with Stephen Nolan to understand
the operation.  Based on these discussions, Bob felt that the AVC technology
could be modeled with IBIS Version 3.2 functionality.  It would use the
Bus_hold submodel to switch in extra drivers based on V_trigger voltages.

Stephen is interested in testing the AVC model with and without the extra
submodels to check both on how good the unimproved model is and on how much
improvement can be achieved using submodels.

100 POINT LIMIT ISSUE (New Topic)
D.C. Sessions briefly indicated that the 100 point limit in IBIS was again
becoming a technical issue.  He will introduce the discussion on the IBIS
reflector.

DIFFERENTIAL INPUT SPECIFICATION FOR SINGLE-ENDED INPUT (New Topic)
Bob Ross opened the discussion by noting that some reflector discussion had
occurred earlier on this issue.  Stephen Nolan had argued that data inputs
for SSTL-2 and SSTL-3 devices should be modeled as differential input pins
even though the negative sides are connected to a common VREF pins.  Several
reasons were presented during the discussion that followed:

  The inputs are physically constructed using differential input buffers
    connected to a common VREF pin.

  At a recent JEDEC meeting, it was shown that a small amount of noise on
    VREF can introduce hundred of picoseconds of delay change.  This needs
    to be modeled using differential input buffers.

  IBIS Version 3.2 does not explicitly prohibit using the same pins for
    differential input and output buffers.  However, the IBIS parser does
    issue an Error for this case.  Stephen argues that this could be
    considered an ibischk3 bug.

  In practice, some designers "abuse" the buffer by actually changing the VREF
    voltage to set logic states or disable the input.

Stephen indicated that he currently issues IBIS models using single-ended
inputs and Vinh and Vinl thresholds to avoid ibischk3 parser error messages.
Bob commented that BIRD62.6 was designed to model this type of input as a
single-ended input with threshold levels made relative to VREF.

Bob stated that one resolution would be to change the Error message issued by
the ibischk3 parser to a Warning message.  This would deal with the reality
that this type of structure is becoming widely used and simulations that
covered such interactions would not be limited by the IBIS structure.  Bob
had previously intended to issue BUG41, but held off when he found some other
interactions.  So he wanted to raise this as a discussion topic.

While the Specification does not have text which prohibits using the same
pins for different inputs of differential buffers, this application was
not anticipated.  Furthermore the parser restriction was by design.

Since there is technically no Specification violation, Bob will send BUG41
to the IBIS reflector and use it as the basis for further reflector and
IBIS meeting discussion.  Depending on the outcome of this discussion, a
BIRD could be issued later to clarify the IBIS Specification.

Bob plans for a vote on BUG41 at the next meeting to resolve this issue.

NEXT MEETING:
The next teleconference meeting will be on Friday, May 26, 2000 from 8:00 AM
to 10:00 AM.  A vote on BUG41 is planned.

==============================================================================
                                      NOTES

IBIS CHAIR: Bob Ross (503) 685-0732, Fax (503) 685-4897
            [email-masked]
            Modeling Engineer, Mentor Graphics
            8005 S.W. Boeckman Road, Wilsonville, OR 97070

VICE CHAIR: Stephen Peters (503) 264-4108, Fax: (503) 264-4515
            [email-masked]
            Senior Hardware Engineer, Intel Corporation
            M/S JF1-209
            2111 NE 25th Ave.
            Hillsboro, OR 97124-5961

SECRETARY:  Guy de Burgh (805) 988-8250, Fax: (805) 988-8259
            [email-masked]
            Senior Manager, Innoveda
            1369 Del Norte Rd.
            Camarillo, CA 93010-8437

LIBRARIAN:  Jon Powell (805) 988-8250, Fax: (805) 988-8259
            [email-masked]
            Senior Scientist, Innoveda
            1369 Del Norte Rd.
            Camarillo, CA 93010-8437

WEBMASTER:  Syed Huq (408) 525-3399, Fax: (408) 526-5504
            [email-masked]
            Manager, Hardware Engineering, Cisco Systems
            170 West Tasman Drive
            San Jose, CA 95134-1706

POSTMASTER: Matthew Flora (425) 869-2320, Fax: (425) 881-1008
            [email-masked]
            Senior Engineer, HyperLynx, Inc.
            114715 N.E. 95th Street
            Redmond, WA 98052

This meeting was conducted in accordance with the EIA Legal Guides and EIA
Manual of Organization and Procedure.

The following e-mail addresses are used:

  [email-masked]
      To join, change, or drop from either the IBIS Open Forum Reflector
      ([email-masked]), the IBIS Users' Group Reflector ([email-masked])
      or both.  State your request.

  [email-masked]
      To obtain general information about IBIS, to ask specific questions
      for individual response, and to inquire about joining the EIA-IBIS
      Open Forum as a full Member.

  [email-masked]
      To send a message to the general IBIS Open Forum Reflector.  This
      is used mostly for IBIS Standardization business and future IBIS
      technical enhancements.  Job posting information is not permitted.

  [email-masked]
      To send a message to the IBIS Users' Group Reflector.  This is
      used mostly for IBIS clarification, current modeling issues, and
      general user concerns.  Job posting information is not permitted.

  [email-masked]
      To report ibischk2/3 parser bugs.  The Bug Report Form Resides on
      eda.org in /pub/ibis/bugs/ibischk/bugform.txt along with reported bugs.

      To report s2ibis, s2ibis2 and s2iplt bugs, use the Bug Report Forms
      which reside under eda.org in /pub/ibis/bugs/s2ibis/bugs2i.txt,
      /pub/ibis/bugs/s2ibis2/bugs2i2.txt, & /pub/ibis/bugs/s2iplt/bugsplt.txt
      respectively.

Information on IBIS technical contents, IBIS participants, and actual
IBIS models are available on the IBIS Home page found by selecting the
Electronic Information Group under:

  http://www.eia.org/eig/ibis/ibis.htm

Check the pub/ibis directory on eda.org for more information on previous
discussions and results.  You can get on via FTP anonymous.
==============================================================================