DATE: 6/2/99 SUBJECT: 5/28/99 EIA IBIS Open Forum Meeting Minutes VOTING MEMBERS AND 1999 PARTICIPANTS LIST: AMP (Martin Freedman) Applied Simulation Technology Raj Raghuram, Norio Matsui, Neven Orhanovic Avanti Nikolai Bannov Cadence Design Mike LaBonte* Cisco Systems Syed Huq* Compaq Bob Haller*, Steve Coe, Shafir Rahman, Maher Elasad Cypress (Rajesh Manapat) EMC Corporation Fabrizio Zanella Fairchild Semiconductor [Peter LaFlamme], Craig Klem H.A.S. Electronics (Haruny Said) Hewlett Packard (EEsof, etc.) Paul Gregory, Henry Wu High Design Technology Razvan Ene HyperLynx Matthew Flora*, Kellee Crisafulli IBM Greg Edlund, Michael Cohen*, Praven Patel Incases Olaf Rethmeier*, Werner Rissiek, David Eagles, Wilhelm Arnoldi, Ulrich Losch Intel Corporation Stephen Peters*, Arpad Muranyi*, Frank Kern, Martin Chang, Dave Moxley, Kerry Nelson*, Jeff Day, Richard Mellitz, Peter Liou LSI Logic (Symbios Logic) Scott King Mentor Graphics Bob Ross*, Mohamed Mahmoud, Sherif Hammad, Jean Oudinot, Markku Kukkanen, Martin Groeber, Karine Loudet Mitsubishi (Tam Cao) Motorola (Ron Werner) National Semiconductor Milt Schwartz North East Systems Associates Edward Sayre, Michael Baxter, Kathy Breda NEC (Hiroshi Matsumoto) Philips Semiconductor Todd Andersen, Peter Christiaans Quantic EMC (Mike Ventham) Siemens Bernhard Unger, Christian Mitschke, Manfred Maurer, Peter Kaiser, Wolfram Meyer, Gerald Bannert, Harmut Ibowski, Katja Zuleeg, Hans Pichlmaier, Eckhard Lenski, Kortheuer Udo, Christian Sporrer SiQual Scott McMorrow Texas Instruments Jean-Claude Perrin, Shankar Balasubramaniah, Ramzi Ammar Thomson-CSF (Jean Lebrun) Time Domain Analysis Systems Dima Smolyansky Viewlogic Chris Rokusek*, Guy de Burgh, Cary Mandel, (Jon Powell) VeriBest Ian Dodd* VLSI Technology D.C. Sessions Zuken-Redac (John Berrie) OTHER PARTICIPANTS IN 1999: 3Dfx Interactive Ken Wu Actel Corporation Silvia Montoya Alcatel Steven Criel Analytical Edge Robert Easson Applied Microelectronics Brian Sanderson BMW Friedrich Haslinger Bogatin Enterprise Eric Bogatin Bosch Telecom Detlef Wolf ECI Telecom Daniel Adar EIA [Patti Rusher], Cecilia Fleming, Dan Heinemeier Electronique Catherine Gross EFM Consulting Ekkehard Miersch Intracon Design Mike Osmond FCI John Ellis Litton Systems Robert Bremer Molex Incorporated Gus Panella Nortel Networks (& Viewlogic) Martin Hall Oce Printing Systems Ernst Deiringer Praegitzer Design Rick Newell Rockwell Collins Susan Tweeton, Ron Hau Samsung Jung-Gun Byun, Cheol-Seung Choi Signals & Systems Engineering Tom Hawkins STMicroelectronics Fabrice Boissieres, Philippe LeFevre StorageTek Nick Krull Sun Microsystems Victor Chang Tektronix Tom Brinkoetter Teradyne Mikhail Khusid VDOL Robert Novosel Xilinx Susan Wu (Unaffiliatied, Retired) Bruce Wenniger 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 Monday, June 21, 1999 DAC99 IBIS Summit Meeting - No Phone 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 attendees. MEMBERSHIP UPDATE AND TREASURER'S REPORT Bob Ross had no update, but still needs to work with Cecilia Fleming on payment status. REVIEW OF MINUTES AND AR'S No corrections were made to the minutes. The AR's will be discussed during the meeting. MISCELLANY/ANNOUNCEMENTS None PRESS AND WEB PAGE UPDATES Bob Ross reported that the June 1999 issue of Integrated System Design (ISD) has an article "EDA Standards for the Millennium" on pp. 17 - 28 which has a table that lists IBIS Version 3.2 as one of the standards. Bob also noted that some IBIS Training Courses have been uploaded to http://www.eda.org/pub/ibis/training/ Per the discussion at the last meeting, Arpad Muranyi made available his "Introduction to IBIS Models and IBIS Model Making" class Power Point slides. These were part of a short course set of tutorials given in April 1999 in Phoenix Arizona by the Arizona State University. These slides were uploaded as Foils99.zip. Also Arpad did a similar presentation in Hannover, Germany in May, 1999. He produced a modified set of slides that did not reference the proprietary IBIS Center program. These Power Point slides were uploaded as Hannover.zip. Bob indicated that Todd Westerhoff announced a downloadable Power Point tutorial "Basic SI and Timing Budgets for Common Clock Designs" on the SI reflector. The material also addresses issues regarding the timing test load and Vmeas in IBIS models. Todd has given Bob permission to upload the slides in the training directory. Bob indicated that there was no vendor-specific content in the presentation and asked the group if there were any objections to uploading this presentation. The group agreed to having the presentation uploaded. AR - Bob Ross upload timing101a.zip to the training directory above [Done]. Syed Huq reported that he has turned over the material to Cecilia Fleming on Upcoming events and the link to the training directory. He did run into a password issue that prevents him from doing the uploads himself. NEW MODELS AVAILABLE, LIBRARY UPDATE Bob Ross reported that the Aptos Semiconductor IBIS model link is down since the operations have been sold. OPENS FOR NEW ISSUES Arpad Muranyi on single ended and differential model selection. INTERNATIONAL/EXTERNAL PROGRESS - IEC 62014-1 (IBIS Version 2.1) - Bob Ross reported that the comments voted on at the last meeting have been submitted to the US Technical Advisory Group (TAG) for formal processing. The comments will be formally forwarded to IEC. After they are processed, the IEC 62014-1 document should be moved to the next phase (FDIS) leading to formal ratification of a Draft International Standard. - pr EIAJ ED-5302 Standard for I/O Interface Model for Integrated Circuits (IMIC) - Bob Ross reported that he and Stephen Peters met with Dr. Norio Matsui and Raj Raghuram on Wednesday, May 12, 1999 to explore further some IBIS and IMIC merger and linkage ideas and issues. This will be discussed later in the meeting. - IEC 93/67/NP IBIS and EMC Simulation Bob Ross had no further report - JC-16.2 Subcommittee: Modeling and Test Bob Ross had no further report. IBIS (EAST) USERS GROUP MEETINGS Bob Haller reported that the IBIS Users Group meeting held on May 20, 1999 at North East Systems Associates was well attended. Since Minutes will be sent out, Bob just briefly summarized the topics covered: IBIS Accuracy Specification Connector Modeling IBIS Training Holding Regular IBIS Users Group Face-to-Face Meetings Bob Ross reported that Kathy Breda has reserved a room on Thursday, October 14, 1999 at the Marlborough Holiday Inn for the IBIS Summit Meeting that occurs at the same time as the PCB Conference East. Bob Haller commented that the IBIS Accuracy Specification Group would like to have actual correlation examples of IBIS models at that meeting. IBIS SUMMIT AT DESIGN AUTOMATION CONFERENCE Bob Ross noted that EIA will have a booth in which an IBIS poster will be displayed. Alpert Designs, Inc. will use last year's IBIS poster but with an updated theme for the new poster. The IBIS Summit Meeting is scheduled for Monday, June 21, 1999 at the Hilton Hotel, New Orleans Riverside (Chequers Room) in New Orleans, Louisiana. The hotel is adjacent to the Ernst M. Morial Convention Center where the Design Automation Conference (DAC) is being held. Bob expects people to show up at 8:30 for refreshments. The meeting should start at 9:00 AM and last into the afternoon. Lunch will be provided to the participants. The tentative Agenda includes: Business & Discussions - Election of Officers for 1999-2000 - Version 3.2 Response Issues - Open BIRDs Discussion - Version 4.X Features Presentations - IBIS 98-99 Overview - Bob Ross, Mentor Graphics - Accuracy Specification Update - Bob Haller, Compaq - ECALS-2 and the EMI Problem - Atsushi Ito, Matsushita - Equation Based Modeling, Arpad Muranyi, Intel Bob estimated that about 17 people have signed up so far. Bob asked Matthew Flora to send out another meeting announcement shortly. [Note on sign-ups: Matthew Flora will handle the sign-ups for the meeting. Some details are already on the Upcoming Events link on the EIA IBIS home page. Matthew can be contacted at mbflora@hyperlynx.com or (425) 869-2320.] AR - Bob Ross and Matthew Flora send out a second announcement for the EIA IBIS Summit Meeting on June 21, 1999. SP-4557 - IBIS VERSION 3.2 LETTER BALLOT Bob Ross reminded everyone to VOTE. A strong show of support is needed for this to be ratified. The EIA letter ballot deadline is Wednesday, June 23, 1999. Bob relayed a report from Cecilia Fleming that the ballot on IBIS Version 3.2 has also been published in the appropriate ANSI document. The ANSI deadline is Tuesday, August 3, 1999. As with IBIS Version 2.1, there may be a brief period of time where IBIS Version 3.2 is an EIA standard before becoming and ANSI/EIA standard. The document being considered and also the form used for voting are accessed from the EIA IBIS home page: http://www.eia.org/eig/ibis/ibis.htm The document is in Adobe format (ver3_2.pdf) and the ballot (SP-4557.pdf) needs to be signed and returned by surface mail or faxed to EIA. Editorial corrections are welcome. COOKBOOK STATUS Stephen Peters had no report. IBIS MODEL REVIEW COMMITTEE DISCUSSION Matthew Flora indicated one request for information on the process. S2IBIS2 MAINTENANCE AND S2IBIS3 Bob Ross started the discussion by indicating that this was a continuation of the discussion at the May 7, 1999 meeting. Bob noted that a s2ibis2 problem reported by Scott McMorrow and a solution were forwarded to an individual who is interested in providing an upgrade. This opened the door to a long discussion on what to do about s2ibis2 maintenance and s2ibis3 generation. Michael Cohen observed that the public domain s2ibis2 utility is widely used as the "official" IBIS model generator. However, he still sees defective models. Syed Huq proposed that we consider hiring a contractor to fix s2ibis2 bugs and do s2ibis3 development. Ian Dodd noted the problem that in order to make s2ibis more portable (for NT operating systems), he had to rewrite the LEX and YACC dependent portions. Mike LaBonte suggested commercial vendor might make available the generic code of their vendor specific s2ibis2 utility. Ian and Matthew Flora noted that users of the utility could provide financial support of the generic utility development. After some more discussion, Ian noted that we need to specify what we want. Bob formed a committee to look into this consisting of Michael Cohen, Ian Dodd, Mike LaBonte and Syed Huq. Bob agreed to provide them with the e-mail addresses. Furthermore Bob will schedule time at the IBIS Summit Meeting on June 21, 1999 for a report since this group plans to attend. The discussion continued. Arpad Muranyi suggested that we might consider a web-based s2ibis utility that does not depend on a locally distributed s2ibis utility. He cited some utilities offered on the Signal Integrity reflector as examples. Michael Cohen cautioned that since s2ibis2 requires flavors of SPICE, he would be restricted to using a commercial SPICE without having dedicated local licenses. He felt that the licensing restrictions would prevent many SPICEs from being used. Chris Rokusek commented that a public domain Berkeley Spice could be used. However, many SPICE models come with commercial SPICE vendor-specific syntax and process models. Bob commented that what is needed are the list of bugs to be fixed, the flavors of SPICE to be supported, and the platforms and operating systems (e.g., UNIX and NT) to be supported. Then potential contractors can provide a bid on doing the s2ibis2 and s2ibis3 upgrades. Currently five flavors are supported. More may be needed plus a means to support semiconductor vendor proprietary SPICEs. LEX and YACC code may need to be replaced with generated code for portability. BUG34 - NO ERROR REPORTED FOR MISSING V/I TABLE IN OUTPUT BUFFERS Bob Ross noted that there is still no revised BUG34 proposal. So the discussion was deferred. Matthew Flora's AR is still open. AR - Matthew Flora issue a revised BUG34 to document the conditions where Warning messages are issued. IMIC AND IBIS Bob Ross reported on a meeting held on Wednesday, May 12, 1999 with Bob, Stephen Peters, Raj Raghuram and Norio Matsui and hosted by Applied Simulation Technology. A number of topics discussed and Bob reported on some of the discussion at that meeting: The team reviewed the history of the activity and then asked what the IBIS Committee and the EIAJ IMIC Committee would want. For background, Bob noted that IBIS Version 3.2 is going through formal national standards body ratification processes. Now is the time to think about future needs including how to relate IBIS with the IMIC proposal. At the meeting Norio stressed that IMIC Committee does not want to see IBIS replaced. The IMIC proposal was developed to provide models for not only Signal Integrity problems, but and also for Power Integrity and EMI problems. Bob noted that IBIS has some specification and information details such as input voltage thresholds, timing test loads, and Model_type that are used for Signal Integrity applications. Norio stated that EIAJ is looking for a merger solution of IBIS and IMIC. Some IMIC members may be advocating a merger or combination of two standards, giving the semiconductor vendors a choice of formats. Bob felt that this flexibility could provide too much of a burden on EDA vendors and customers. For just Signal Integrity applications, there was no proven benefit that one approach was better than the other. Bob noted some syntax/structural incompatibility details between IBIS and IMIC. Allowing a mixture of information might result in incomplete information for the application. Bob commented that commercial/EDA vendors provide many IBIS models to deal with user needs. At the meeting the proposals were positioned as follows with respect to SPICE and to levels of abstraction: IBIS - Behavioral IMIC - Behavioral and Structural SPICE - Structural The higher level formats can be derived from the lower level formats. Norio noted that IBIS has a fixed model that requires syntax changes for enhancements. IMIC supports a network description and is more flexible. We explored in more detail what is really the preferred level of merger by each group. Norio indicated that he would like IBIS to support netlists. Also he would like to see IBIS support table level transistor models. Bob indicated that it would be useful if IMIC supported a complete IBIS Buffer [Model] syntax as a 5-7 terminal element (4 power rails, I/O, and possibly input and enable) in IMIC. We looked at independent positioning with linkages. This would allow each standard to be optimized for its application and still leverage the data in the other standard. IBIS could call IMIC (or SPICE) transistor models and netlists. Netlists could be used for packages. EIAJ is looking at consumer electronics, automobile microprocessors, ASICS, and faster applications. IMIC or IBIS could be used for system level applications. For automotive electronics, the location of the ground reference is becoming a fundamental issue, and EMI/EMC are big concerns. We agreed that complex package modeling is very difficult with both the IMIC and IBIS approaches. A simplified approach may be useful. Norio noted that the IMIC Committee is monitoring an EIAJ EMI activity called ECALS-2. Norio also mentioned that an IMIC Meeting will be held on June 1, 1999 to discuss the comments of this meeting. Stephen Peters provided some additional observations about the meeting. He felt that the IMIC format could provide a longer term EMI and Power Integrity solution. IMIC was potentially superior in dealing with SSO analysis. The network description was appealing for package modeling. Stephen noted that a fundamental problem with IMIC format is that it needs a netlist level buffer description to support the transistor level table SPICE approach. Stephen did not see how IMIC could replace IBIS unless some specific advantages were demonstrated. Bob noted that they discussed other topics including simulator performance and the IBIS Series Model element. Bob concluded the report of the meeting and stated that we need specific proposals and justification in order to proceed toward any of the merger proposals above. BUG34 - NO ERROR REPORTED FOR MISSING V/I TABLE IN OUTPUT BUFFERS Bob Ross noted that since no revised BUG34 proposal was generated, the discussion was deferred. Matthew Flora's AR is still open. AR - Matthew Flora issue a revised BUG34 to document the conditions where Warning messages are issued. BIRD58.2 - DRIVER SCHEDULE KEYWORD CLARIFICATION Arpad Muranyi commented on the history of BIRD58.2 starting with the original intent of adding a critical paragraph that existed in the original BIRD35.3. Based on subsequent feedback, more clarification detail was added to BIRD58.2 while retaining the original technical intent. Bob Ross and others commented that BIRD58.2 clarified a number of points. Bob called for any comments. Bob suggested a minor editorial change to change the order of the detailed description of the delay columns to the same order as the syntax: Rise_on_dly, Rise_off_dly, Fall_on_dly, and Fall_off_dly. Also Bob suggested improving the wording of the clause in the last sentence of four paragraphs (note OFF and ON are interchanged as appropriate): (if they were not turned OFF and ON by another event yet, respectively). After some discussion Matthew Flora suggested the correction: (if they were not already turned OFF and ON, respectively, by another event). With no further comments, Bob Ross called for a vote on BIRD58.2 with the modifications above (to be issued as BIRD58.3). BIRD58.2 as modified was approved by unanimous vote. AR - Arpad Muranyi issue approved BIRD58.3 with the changes above. [Done] The editorial changes of BIRD58.3 will be submitted as an editorial comment and are expected to be part of the EIA and ANSI Version 3.2 document. NUMBER OF POINTS IN VT TABLE Bob Ross introduced the issue that IBIS has a 100 point limit on all tables. This limit may not be adequate for certain circumstances and for automated IBIS model generation. Chris Rokusek stated he would support allowing more points for better accuracy. He thought that in most cases the points need to be properly filtered in order to achieve good accuracy with 100 points or less. Mike LaBonte commented that he has seen high frequency effects that change the simulation between filtered and unfiltered tables. Bob Haller noted that an internal tool has a 1000 point limit in tables. Michael Cohen has seen IBIS models with data points in tables commented out to comply with the 100 point restriction. Arpad Muranyi elaborated on the issue. The IBIS Specification is clear that for VI tables, the 100 point limit applies to the voltage axis. However for VT tables, it is not clear whether the 100 point limit applies to the time axis or to each of the voltage columns. The historical rationale for the 100 point limitation was that some SPICE controlled source table formats were limited to 100 table points. Furthermore, Arpad indicated that the 100 point limit was not a problem for the VI tables. He has an algorithm to select the best 100 points out of a larger number of extracted points. The points at which the maximum table curvature occurs is in the same region for VI tables. However, VT tables provide the biggest challenge for providing accurate data with 100 points. The typical, minimum, and maximum column waveforms tend to be shifted with respect to each other. The points of maximum curvature where you want the highest density of points tend to be in different regions of the time axis. Stephen Peters also noted that he has seen the areas of maximum curvature to be at different time regions. So each table could be theoretically limited to having a different set of 33 time points spread out in different time regions. This could provide a much courser resolution for each of the columns and could compromise the accuracy of the data. In a SPICE implementation of IBIS comparison with the structural SPICE model simulation, Arpad encountered a situation where more VT points were needed to achieve acceptable accuracy. The general agreement was that the 100 point limit should be relaxed. Bob Ross listed some options: Do nothing - keep the 100 point limit Allow the 100 point limit to be interpreted for each column Raise the 100 point limit to a higher number (say, 1000 points) Do not provide a limit. The consensus was to provide a conservative limit such as 1000. If no limit is provided, valid IBIS models might be created with an unnecessarily large number of points. This could create very large databases and slow down the simulations. The option of changing the limit to apply to each column appeared to be an unnecessary complication in any model generation utility such as s2ibis2. Arpad commented that he allows the option to fill in the NA data with numerical values. Even though the 100 point limitation is in IBIS Version 3.2, the ibischk3 parser could be changed to issue a Warning message instead of an error message since there are cases where the additional points are needed. Bob Ross commented that a BIRD needs to be generated for IBIS Version 4.X to increase the number of points. 1001 points would allow numerically nice endpoints such as 0 and 10 ns with equally spaced points for easy automated generation. However, it should be recommended that more than 100 points should be used only in situations where it is necessary for accuracy. Arpad commented that in any case, the IBIS Specification needs to be clarified concerning whether the limit applies to the number of rows in the table (X-axis) or to the number of numerical data values in each column (Y-axis). CONNECTOR PROPOSAL REVIEW Matthew Flora reported that Gus Panella is working on a description of the matrices in the Connector Model proposal. SINGLE ENDED AND DIFFERENTIAL MODEL SELECTION (New Issue) Arpad Muranyi raised the concern on the IBIS reflector that some devices have outputs which can be used for differential or single ended operation. Michael Cohen added that he uses a SCSI chip with these characteristics. There is no provision within IBIS Version 3.2 to handle this in one component. The solution on the reflector was to provide two separate component models. Bob Ross indicated that this was the correct response. We have discussed this issue in the past. To resolve this within IBIS we might have to write a BIRD on a differential model selector. IBIS 4.X FEATURES Bob Ross briefly mentioned some features requested for IBIS Version 4.X: Input Tables Removal of 100 Point Limit Differential Overshoots Possible SPICE/IMIC Linkages for Netlists and Models EMI Extensions Connector Models Accuracy Specification Extensions Syed Huq added that differential loads should be considered. Bob noted that more discussion should occur at the IBIS Summit Meeting. Final comment - Bob Haller would like to reserve some meeting time for the IBIS Accuracy Specification Issues. Bob suggested that the changes will be introduced at the Summit. Discussion can be scheduled at the next teleconference meeting. NEXT MEETING: The next meeting is the EIA IBIS Open Forum Summit Meeting on Monday, June 21, 1999 in the Hilton Hotel in New Orleans, Louisiana. ============================================================================== NOTES IBIS CHAIR: Bob Ross (503) 685-0732, Fax (503) 685-4897 bob_ross@mentor.com Modeling Engineer, Interconnectix BU of Mentor Graphics 8005 S.W. Boeckman Road, Wilsonville, OR 97070 VICE CHAIR: Stephen Peters (503) 264-4108, Fax: (503) 264-4515 sjpeters@ichips.intel.com Senior Hardware Engineer, Intel Corporation M/S JF1-56 2111 NE 25th Ave. Hillsboro, Oregon 97124-5961 SECRETARY: Matthew Flora (425) 869-2320, Fax: (425) 881-1008 mbflora@hyperlynx.com Senior Engineer, HyperLynx, Inc. 17641 NE 67th Court Redmond, WA 98052 LIBRARIAN: Jon Powell (805) 988-8250, Fax: (805) 988-8259 jonp@qdt.com Senior Scientist, Viewlogic Systems (formerly Quad Design) 1385 Del Norte Rd., Camarillo, CA 93010 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: ibis-request@eda.org To join, change, or drop from either the IBIS Open Forum Reflector (ibis@eda.org), the IBIS Users' Group Reflector (ibis-users@eda.org) or both. State your request. ibis-info@eda.org 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. ibis@eda.org 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. ibis-users@eda.org 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. ibischk-bug@eda.org 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 Check the pub/ibis directory on eda.org for more information on previous discussions and results. You can get on via FTP anonymous. ==============================================================================