Subject: IBIS: 4/29 Minutes

From: Derrick Duehren <[email-masked]>
Date: Wed, 4 May 94 21:20:02 PST

Text item: Text_1

Date:    May 4, 1994

From:    Will Hobbs (503) 696-4369, fax (503) 696-4210
         [email-masked]
         XTG Modeling Manager, Intel Corp., Chairperson, IBIS Open Forum
         Intel Corporation
         5200 NE Elam Young Pkwy, Hillsboro, Oregon 97124 USA
         and
         Derrick Duehren (503) 696-4299, fax (503) 696-4904
         [email-masked]
         Intel Program Manager

Subject: Minutes from IBIS Open Forum 4/29/94

To:
Anacad                        Steffen Rochel
Ansoft                        Henri Maramis
Atmel Corporation             Dan Terry
Cadence Design                Sandeep Khanna, Chris Reed,
                              Kumar*
Contec                        Maah Sango, Clark Cochran
Digital Equipment Corp.       Barry Katz*
High Design Technology        Michael Smith
HyperLynx                     Steve Kaufer, Kellee Crisafulli*
IBM                           Jay Diepenbrock
IBM-Motorola alliance         Lynn Warriner, Hoa Quoc*, John Burnett
Integrity Engineering         Greg Doyle, Wayne Olhoft
Intel Corporation             Stephen Peters*, Don Telian, Will Hobbs*
                              Arpad Muranyi*, D. Duehren*, R. Rosenbaum*
Interconnectix, Inc.          Bob Ross*
Intergraph                    Ian Dodd, David Wiens
IntuSoft                      Charles Hymowitz
Logic Modeling Corp.          Randy Harr
Mentor Graphics               Greg Seltzer, Ravender Goyal
Meta-Software                 Mei Wong, Mei-Ling Wei
MicroSim                      Arthur Wong, Jerry Brown, Graham Bell
National Semiconductor        Syed Huq*
North Carolina State U.       Paul Franzon, Michael Steer, Steve Lipa
Performance Signal Integrity  Vivek Raghawan, Eric Bracken*
Quad Design                   Jon Powell*
Quantic Labs                  Mike Ventham, Zhen Mu
Racal-Redac                   John Berrie
Siemens Nixdorf               Werner Rissiek, Olaf Rethmeier
Texas Instruments             Bob Ward*
Thomson-CSF/SCTF              Jean Lebrun
Zeelan Technology             Hiro Moriyasu, George Opsahl*

CC:
Intel Corporation             Randy Wilhelm, Jerry Budelman,
                              Intel IBIS team

In the list above, attendees at the meeting are indicated by *

Upcoming Meetings: The room and bridge numbers for future IBIS 
teleconferences are listed below:
                    Date        Bridge Number   Reservation #
                    5/13/94    (415) 904-8944   721619
                    5/20/94    Face-to-face, editing committee
                    5/27/94    (415) 904-8800   744468

All meetings are 8:00 AM to 10:00 AM PST (15:00 to 17:00 UTC).  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 and give the bridge operator the reservation number.

If you know of someone new who wants to join the e-mail reflector 
([email-masked]) send e-mail to [email-masked].

NOTE: "AR" = Action Required.

------------------------------------------------------------------------

4/15/94 Meeting Agenda
----------------------

Check-in
Intros of new IBIS participants                       Hobbs
Review of previous meeting's minutes                  Hobbs
Miscellany/Announcements                              Hobbs
Opens for new issues                                  All
Opens for new issues                                  All
New models available                                  All
IBIS 2.0 Ratification/DAC/Other 2.0 Issues            Hobbs
-  Birds of a Feather session (6/8)
-  Rev 2.0 Ratification Summit (6/9)
-  Levels of support (see 12/3/93 discussion)
IBIS Cookbook                                         Hobbs, Rosenbaum
BIRD 8, Spec. of V/I data monotonicity                Crisafulli
BIRD 9.2,  Terminator Specification                   Ross
BIRD 10, Coupling effects in package models           Bracken
BIRD 11, Sign of current checking                     Hobbs, All
BIRD 12, Non-Linear Ramps                             Peters
BIRD 2, VIH, VIL Thresholds for Inputs                Powell
Egg 3, Simulation temperatures                        Ward
The rest of the nest (Eggs 4, 5...)                   All
Wrap-up, Next Meeting Plans                           Hobbs

------------------------------------------------------------------------

1.  Intros of new IBIS participants
New participants: None.

2.  Review of Pervious Meeting's Minutes
The following correction was made to last month's minutes: In item 12, 
"Bob W." should be "Bob R."

3.  Miscellany/Announcements
Barry believes ad-hoc nature of ibis forum causes problems for DEC.  He 
prefers $500 dues, rather than a source license (easier for corporations 
to justify).  Will gave a short history of the Golden Parser licensing.  
We will discuss this issue at the ratification meeting.

IBIS is mentioned briefly in Steve Ohr's column in Computer Design, 
April 1994, pg. 112.

The vhdl.org \birds directory is up-to-date as of 5/3/94.

4.  Opens for new issues
BIRDs 13 and 14 added to the agenda.

5.  New models available                      
The IntelDX4(TM) processor and Pentium(TM) processor-to-PCI bridge 
component IBIS files have been posted to vhdl.org.

6.  IBIS 2.0 Ratification/DAC                 
    -  May 20 Editing Committee 
       AR Derrick: Get room, time, hotel info out to May 20 participants 
       within next week.  DONE

       The agenda for the ratification meeting will be published after 
       the May 20 meeting.

       Old AR Will: Engage Paul Munsey after 5/20 for parsability study 
       of the proposed version 2.0 to minimize a need for a version 2.1 
       soon after 2.0.

    -  Rev 2.0 Ratification Summit (6/9/94)
       Kumar has arranged a room near the conference center for 30 to
       40 people.

    -  Birds of a Feather session (6/8/94)
       No discussion.  Arrangements are made for a Marriott room.

    -  Levels of support (see 12/3/93 discussion)
       Will be discussed at the ratification meeting.

9.  IBIS Cookbook  
Robin Rosenbuam (an Intel Technical Writer) led a short discussion of 
the cookbook.  Kellee and Jon received and reviewed copies, and will be 
giving Robin their comments.  Will asked for volunteers to create new 
examples for the book; no one volunteered.  Hoa Quoc requested a review 
copy.  Robin later tried to send it to an email address Hoa provided, 
but the address failed.

AR Hoa:  Call Robin at (503) 696-4554 to make arrangements.  Also please 
provide name, address, phone number, etc. to Derrick for the Roster 
document.

11. BIRD 8, Spec. of V/I data monotonicity    
We need resolution to Jon and Arpad's disagreement.  Originally, the 
forum requested that IBIS require monotonicity of data, which Kellee 
codified in BIRD 8 and later revised to only require one monotonic axis.  

Most of the discussion revolved around what is and is not monotonic.  
Non-zero?  Non-slope changing?  No change in sign of slope?  Slope going 
to zero?  We concluded that zero slope is OK, we can allow "flat spots", 
and could issue a warning for non compliance.

Jon feels nonmonotonic behavior can only take place in the presence of 
feedback, which implies delay, which IBIS doesn't describe.   Some 
simulator vendors currently filter out non-monotonic data.

Will proposed: Require monotonic data on at least one axis.  Simulators 
can issue a warning message to customers if data on the other axis is 
monotonic.  Customers can put whatever they want in the model.  It would 
be very difficult to have the GP do the filtering.  We can put a 
guideline/note in the spec.: "If you have non-monotonic data, some 
simulators will convert it to monotonic data."  Simulator vendors are 
responsible for warning user how it will be handled (e.g., filtered 
out).

Barry wants an example of a nonmonotonic transistor.  Arpad said the 
irf50 CMOS transistor is an example.

AR Kellee: Update BIRD 8 per this discussion.

12. BIRD 9, Other model types 
Vote taken: Approved unanimously with the Model_type name changes from 
"Discrete" to "Terminator".

AR Bob R.: Update the approved BIRD and post to the reflector.

13. BIRD 10, Coupling effects in package models
Digital and TI have this data and will likely make it available under 
this BIRD.
Vote taken: Approved unanimously.

14. BIRD 11, Sign of current checking
Vote taken: Approved unanimously.

15. BIRD 12, Non-linear Ramps
Stephen Peters clarified some misunderstandings, proposed a few 
additions to the BIRD.  We need to be able to optionally override the 
package parameters.  

Kellee suggested allowing R_pkg, etc., to be overridden.  He suggested 
naming the sub-parameters the same as for the package with _dut <device 
under test> suffix.  Also add a drawing.

The end point of the waveform must line up with the steady DC state 
current, according to the discussion.  However, measurement errors will 
inevitably prevent the steady, DC states to not line up.  This is the 
model creator's problem.  Bob Ward recommends that we add a steady-state 
agreement as part of the measurement guideline.

Kellee suggested limiting the table length to 100 entries, others 
agreed.

We discussed supporting more complex loads, and concluded no one would 
trust the reference waveforms in the model into anything but fairly 
simple loads, due to low quality transmission line models in older 
simulators.  The consensus is to keep only simple r, l, c loads, not 
topologies such as the PCI speedway.

Jon: We need to figure out a way to sync up the curves -- VT curves in 
different tables, the starting point or some point has to be able to 
correlate the waveforms in time.  Jon proposed that we create 2 pictures 
for forum review, one to sync curves, one to ???

AR Stephen:  Reissue the BIRD per this discussion.  Revise names, add 
c_dut, l_dut, r_dut, Set max of 100 data points in the table, set 
character limits, and add a schematic showing where these elements go.  
DONE

16. BIRD 2, VIH, VIL Thresholds for Inputs     
Vote taken: Approved unanimously.

17. BIRD 13, Simulation temperatures           
Bob W. put this BIRD out to get discussion going.  This BIRD could 
migrate into a simple wording-fix BIRD for the IBIS specification.  It 
clarifies that temperatures are die temperatures, not ambient.  Also, 
bjt min and max are backwards.

AR Will:  Send note to Bob W. with suggested wording change to Version 
1.1 spec.

Discussion to continue via the reflector.

18. The rest of the nest (Eggs 4, 5..., BIRD 14)
No discussion.

19. Wrap-up, Next Meeting Plans                
Next meeting is 5/13/94.