IBIS Open Forum Minutes Meeting Date: November 19, 2013 Meeting Location: Taipei, Taiwan VOTING MEMBERS AND 2013 PARTICIPANTS Agilent Technologies Radek Biernacki, Pegah Alavi, Heidi Barnes, Fangyi Rao, Colin Warwick, Tarun Kalwani, Ming Yan, Xingdong Xue, Zaokai Yuan, Xianzhi Zhao, Ming-Chih Lin*, Peter Lin* Altera David Banas, Hsinho Wu ANSYS [Luis Armenta], Ben Franklin, Dan Dvorscak, Steve Pytel, Lan Chen, Timothy (Gang) Chen, Minggang Hou, Jianbo Liu, Roger Luo, Peng Wang, Shulong Wu, Guoli Yi, Daniel Chang*, Richard Chen*, Naijen Hsuan*, Charlotte Wang*, Jean Wang*, Jerry Wang*, Benson Wei* Applied Simulation Technology Fred Balistreri, Norio Matsui Cadence Design Systems [Terry Jernberg], Joy Li, Yingxin Sun, Ambrish Varma, Kevin Yao, Brad Brim, Aileen Chen, Lanbing Chen, Raymond Y. Chen, Heiko Dudek, Jiayuan Fang, Zhiqiang (Johnny) Fang, Henry He, Jinsong Hu, Li Li, Maofeng Li, Ping Liu, Yubao Meng, Zuli Qin, Aaron Tang, Haisan Wang, Yun Wang, Yitong Wen, Janie Wu, Yanrui (Clark) Wu, Dingru Xiao, Benny Yan, Wenjian Zhang, Zhangmin Zhong, *Tric Chiang, Thunder Lay*, Jack (Wei-Chang) Lin*, Paddy Wu*, Candy Yu* Ericsson Anders Ekholm*, Martina Fiammengo, Markus Janis* Foxconn Technology Group Leo Cheng*, Po-Chuan (Eric) Hsieh*, Alex Tang* Huawei Technologies Yu Chen, Xiaoqing Dong, Jing Fu, Chen Han, Peng Huang, Jinjun Li, Lingfei Li, Luya Ma, Xiao Peng, Xinlu Peng, Haili Wang, Shengli (Victory) Wang, Zhengrong Xu, Hongxian Yi, Gezi Zhang, Zhengyi Zhu IBM Greg Edlund, Adge Hawes, Dale Becker Infineon Technologies AG (Christian Sporrer) Intel Corporation Michael Mirmak, Mohammad Bapi, Stewart Gilbert, Ravindra Rudraraju, Kang Nan, Weifeng Shu, Ming Wei, Jimmy Hsu*, Thomas (YiRen) Su* IO Methodology Lance Wang* LSI Brian Burdick, Sarika Jain, Xingdong Dai, Anaam Ansari, Min Huang Maxim Integrated Products Hassan Rafat, Mahbubul Bari, Ron Olisar Mentor Graphics Arpad Muranyi, Ed Bartlett, Vladimir Dmitriev- Zdorov Micron Technology Randy Wolff Signal Integrity Software Walter Katz, Mike LaBonte, Mike Steinberger, Todd Westerhoff Synopsys John Ellis, Ted Mido, Scott Wedge, Rinsha Reghunath, Xuefeng Chen, Jinghua Huang, Yu Wang Teraspeed Consulting Group Bob Ross, Tom Dagostino Toshiba (Yasumasa Kondo) Xilinx (Raymond Anderson) Zuken Masaud Raeisi, Reinhard Remmert, Michael Schaeder, Alfonso Gambuzza OTHER PARTICIPANTS IN 2013 Accton Technology Group Ching-Hwei Tsend*, Xian-Wei Wang* ASE Group Hink Chung*, Jarris Kuo* ASUSTek Computer Vincent Lu* AU Optronics Corp Jason Kuo*, Joe Shih* Avant Technology Elvis Li, Linda Sun, Jyam Huang*, Enson Lee* Bayside Design Elliot Nahas Celestica Lei Liu, Fei Xue Chinese Electronics Technology Shujun Wei, Tianjiao Wu Company Institute #52 (CETC52) Cisco Systems Biao Chen, Feng Wu, Iris Zhao Computer Simulation Technology Heiko Grubrich Compal Electronics Scott C.H. Li* Contech Zheng Tang Coriant Bruce (Zhenshui) Qin Delta Networks Skipper Liang* Eastwell Xuanjiang Shen, Xiuqing Ye ECL Advantage Thomas Iddings Etrain China Weichun Lu FiberHome Technologies Group Shengyao Wan, Xuanjun Xia Freescale Jon Burnett Granite River Labs Vamshi Kandalla, Miki Takahashi H3C Lichen Li, Xiaoxiang Li Hewlett-Packard Yongjin Choi, Ting Zhu Himax Technologies Falco Chuang*, Lee Renee*, Austin Wang*, Josh Wu* Hisense Aofeng Qian ILI Technology Corp Tieyan Chang*, Chia-Chen (Trevor) Wu* Inventec Zhong Peng KEI Systems Shinichi Maeda Lenovo John Lin*, Alan Sun* Marvell Technology Group Weizhe Li, Fang Lv, Banglong Qian, Yuyang Wang Mediatek Gerald Hsu*, Fandy Huang* Micro-Star International Ethan Huang*, Anthony Liang*, PeterTsai*, Cloud Tseng* Molex Davi Correia, Greg Fu, Satish National Instruments Lee Mohrmann Nokia Siemens Networks Xuhui (Helen) Chen, Gino Guo, Gang Zheng Novatek Microelectronics Corp Jasper Cheng*, Willy Lin*, Frank Pai* Nvidia Eric Hsu, David Chen*, Alan (Chia Yuan) Hsieh*, MT Lin*, Chih Wei Tsai* Open Silicon Norman Chang* Pegatron Corp Lawrence Ting* Qualcomm Scott Powers QLogic James Zhou RDA Microelectronics Ke Cao SAE (Chris Denham) Semiconductor Manufacturing Sheral Qi International Corp. Shanghai Microsystem and Chi Xu Information Technology Institute Shanghai United-Imaging Xi Huang, Yuan Liu, Jirui Lu, Chun Yuan, Yi Zhao Spreadtrum Communications Lily Dai, Steven Guo Shanghai Sunplus Technology Forest Hsu*, Yi-Tzeng Lin* TechAmerica [(Chris Denham)] Teledyne LeCroy Xuanfeng Wu, Ting Zhao Teradyne Raymond Yakura Test Research Mike Wang* Université de Brest Mihai Telescu University of Illinois Tom Comberiate, José Schutt-Ainé, Xu Chen VeriSilicon Tina Xu VIA Labs Sheng-Yuan Lee* VIA Telecom Jen-Hung (Eddie) Lin*, Jacky Liu* Vitesse Semiconductor Sirius Tsang Winbond Electronics Corp Albert (Cheng-Han) Lee*, Marko (Chien- Cheng) Lin* Zhejiang Uniview Technologies Huanyang Chen, Fei Ye ZTE Corporation Huifeng Chen, Fengling Gao, Tao Guo, Hui Jiang, Zhi Zhou, Shunlin Zhu 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 Meeting Number Meeting Password November 22, 2013 Asian IBIS Summit - Yokohama – no telephone bridge December 6, 2013 205 475 958 IBIS For teleconference dial-in information, use the password at the following website: https://ciscosales.webex.com/ciscosales/j.php?J=205475958 All teleconference meetings are 8:00 AM to 9:55 AM US Pacific Time. Meeting agendas are typically distributed seven days before each Open Forum. Minutes are typically distributed within seven days of the corresponding meeting. When calling into the meeting, follow the prompts to enter the meeting ID. For new, local international dial-in numbers, please reference the bridge numbers provided by Cisco Systems at the following link: http://www.cisco.com/web/about/doing_business/conferencing/index.html NOTE: "AR" = Action Required. ---------------------------------------------------------------------------- --------------------------------------------------- WELCOME AND kEYNOTE COMMENTS The Asian IBIS Summit took place on Tuesday, November 19, 2013 at the Sherwood Hotel in Taipei. Approximately 64 people from 28 organizations attended. The statements below summarize the material presented. More details are available through the summit presentations posted online at: http://www.eda.org/ibis/summits/nov13b/ Lance Wang convened the meeting and introduced Daniel Chang of ANSYS for his comments. Daniel welcomed the attendees and thanked the IBIS Open Forum for their ongoing support of the IBIS Summit series in the Republic of China. Lance continued by thanking the co-sponsors: the major sponsor ANSYS and also the co-sponsors Cadence Design Systems, Intel Corporation, IO Methodology, and Synopsys. INTRODUCING IBIS 6.0 Michael Mirmak (Intel Corporation, USA) [Presented by Lance Wang (IO Methodology, USA)] Lance Wang noted that IBIS 6.0 was released September 20, 2013. Major additions focus on IBIS-AMI including added support for redrivers and retimers and IBIS-ISS and Touchstone. The document is now easier to read and use. Lance gave detailed examples of modeling a mid-bus repeater. In IBIS 6.0, IBIS-ISS can be used to represent the complex analog buffer behavior of an AMI model. Multiple files in different locations is now supported for AMI models. Use of IBIS 6.0 improved analog modeling can help ensure model portability. Among issues to resolve is improving IBIS package modeling. Package modeling formats are being discussed with a target to include an update in the next major IBIS release. Developing an IBISCHK6 syntax parser is a focus now. IBIS SUMMARY DOCUMENTS Bob Ross (Teraspeed Consulting Group, USA) [Presented by Anders Ekholm (Ericsson, Sweden)] Anders Elkholm presented information about several documents created by Bob Ross to accompany the IBIS 6.0 specification release. IBIS 6.0 contains a keyword hierarchy tree in section 3.1. Bob updated an unofficial hierarchy document from 2007 with information from IBIS versions 5.1 and 6.0. Extra information in this document includes when items were added at major versions. Bob also created an unofficial evolution document featuring updated columns showing major version evolution, rules and changes evolution and significant subparameter selections such as the *_type subparameter choices. Anders also noted that Bob helped create four new summary tables in section 10.7 of the IBIS 6.0 specification. These tables include Usages, Types and Formats for Reserved Parameters and Types for Format values. The summary information provides quick references for IBIS and IBIS-AMI syntax. The documents are found on the IBIS website along with the IBIS 6.0 specification. A comment was made that we hope the IBIS committee can provide some real examples, not only the specification. Anders responded that this was a good idea. We now have some AMI models as examples. We could add others as well. We hope the chip vendors can help as well. MODELING, EXTRACTion AND VERIFICATION OF VCSEL MODEL FOR IBIS AMI Zhaokai Yuan (Agilent Technologies, PRC) [Presented by Ming-Chih Lin (Agilent Technologies, ROC)] Ming-Chih Lin began by introducing the various components of an optical Rx/Tx module. To simulate an optical link, IBIS-AMI can be extended to model the optical channel. The entire optical module is treated as a mid- channel repeater, and all optical behaviors are encapsulated inside the optical model. Ming-Chih then described the basics of the Vertical Cavity Emitting Laser (VCSEL). Ming-Chih went on to describe the principles of modeling the VCSEL’s performance versus thermal behavior. Measured curves of LI, VI and frequency response were modeled using curve fitting algorithms. VCSEL model verification was then performed on two different devices and a full optical link. A question was asked about how to use this method for long distance transmission cases. Ming-Chih responded that this method is for short distance clock transfer. Long distance transfer will need to include more effects. ANISOTROPIC SUBSTRATES Variance FOR IBIS-AMI SIMULATION Naijen Hsuan (ANSYS, ROC) Naijen Hsuan presented that anisotropic substrate variance is a real physical issue that leads to variation in channel characteristics for high speed SerDes channels. FR4 fiber weave creates local dielectric constant variation leading to insertion loss variation and differential pair skews. Varying the angle of the weave relative to the channel layout leads to variation in differential insertion loss, phase and return loss. Naijen setup a Design of Experiments (DOE) to look at optimizing an Rx CTLE while looking at sensitivities to anisotropic substrate variance. Response surface modeling helped to look at a huge number of possible combinations in order to find optimal solutions. A High Performance Computing (HPC) solution also helped reduce the analysis time. MORE ON IBIS MODELING FOR LOAD-DEPENDENT CURRENT-MODE DIFFERENTIAL DRIVERS Lance Wang (IO Methodology, USA) Lance Wang presented a methodology for modeling load-dependent current-mode differential pair buffers. These buffers are found increasingly often in GHz serial link designs, and traditional IBIS buffer extraction methods are not accurate enough for modeling them. Lance detailed an enhanced I-V and V-T extraction method. Correlation shows matched results between IBIS and Spice. Lance summarized that two enhancements to IBIS would be useful for these buffers. One enhancement would be to include Rref_diff/Cref_diff loads for regular IBIS differential pair models. A second enhancement when modeling dynamic PLL current mode buffers would be to include various I-V tables for different differential loads and a current dependent C_comp value table. A comment was made that these kinds of buffers use one side with pullup and one side with pulldown for rising and falling transitions. Will this method give inaccurate results of P and N pins that are not balanced? Lance responded that this is true. However, luckily, most of these buffers are balanced. AN ADVANCED BEHAVIORAL BUFFER MODEL WITH OVER-CLOCKING SOLUTION Yingxin Sun and Raymond Y. Chen (Cadence Design Systems, USA) [Presented by Thunder Lay (Cadence Design Systems, ROC)] Thunder Lay began by describing the mechanisms related to overclocking of IBIS models. A simulator that does not properly window V-T data will give incorrect results, sometimes showing missing bits. V-T windowing works well for IBIS 4.2 models. However, for IBIS 5.0 models that include I-T data, using the same V-T windowing algorithm will cut off the pre-driver current seen in the composite current I-T data. Thunder proposed an advanced over-clocking solution, where a pre-driver stage was added to the driver stage. With this model, the composite current could be broken into two portions, the contribution from the driver and the contribution from the pre-driver. The proposed over-clocking solution could be implemented into an advanced IBIS simulator to automatically handle the windowing of both V-T and I-T data. With this solution, very good correlation was seen between IBIS and the original transistor model for real SSO simulation, even under over-clocking scenarios. COMBINED I-V TABLE CHECKING PROBLEM Bob Ross*, Yingxin Sun** and Joy Li** (*Teraspeed Consulting Group, **Cadence Design Systems, USA) [Presented by Anders Ekholm (Ericsson, Sweden)] Anders Ekholm began by describing BUG140, where unexpected non-monotonic warnings are issued for combined I-V tables. There is no specification requirement that individual or combined I-V tables be monotonic. Combined table checks were added to the IBIS parser following BUG94. Non- monotonicity often occurs outside of normal simulation regions (clamp regions) and is not a problem for simulation software. Anders walked through a simple example to demonstrate how piecewise linear interpolation methods can cause non-monotonicities when combining two data sets. Anders then showed two test case examples from BUG140. The Quality task group discussed several options for fixes including using more complicated SPLINE fitting algorithms. The final resolution was to change the warning to a note. IBIS MODEL FOR IO-SSO ANALYSIS Thunder Lay and Jack W.C. Lin (Cadence Design Systems, ROC) [Presented by Jack W.C. Lin (Cadence Design Systems, ROC)] Jack W.C. Lin began by defining Simultaneous Switching outputs Noise (SSN). SSN impacts timing and noise margin and becomes a bigger problem as voltages decrease and data rates increase. Traditional SSN simulations can be pessimistic when the analysis excludes an on-die decoupling model or includes an estimated on-die decoupling model. An accurate RC or distributed chip PDN model is needed for realistic power/ground noise analysis. Jack showed a method of using [External Circuit] in IBIS 5.1 to incorporate on-die and package models into the buffer. Jack then showed a case study of a DDR data byte lane including a power-aware IBIS model, on- chip decoupling model and PCB and package S-parameters converted to broadband-Spice models. Without a chip PDN model, SSN is overestimated. With an on-die RC PDN model, the noise is underestimated. Using a distributed broadband model of the on-die PDN gave the most realistic results. Jack summarized that for tighter timing and noise budgets in LPDDR3 or DDR4, system level SSN analysis is helpful for design margin assessment. CONCLUDING ITEMS Lance Wang thanked the co-sponsors, presenters and attendees for their participation and support. The meeting adjourned at 4:30 p.m. NEXT MEETING The Asian IBIS Summit – Yokohama will be held November 22, 2013. The next IBIS Open Forum teleconference will be held December 6, 2013 from 8:00 to 10:00 a.m. US Pacific Time. ======================================================================= NOTES IBIS CHAIR: Michael Mirmak (916) 356-4261, Fax (916) 377-3788 michael.mirmak@intel.com Data Center Platform Applications Engineering Intel Corporation FM5-239 1900 Prairie City Rd., Folsom, CA 95630 VICE CHAIR: Lance Wang (978) 633-3388 lwang@iometh.com President/CEO, IO Methodology, Inc. PO Box 2099 Acton, MA 01720 SECRETARY: Randy Wolff (208) 363-1764, Fax: (208) 368-3475 rrwolff@micron.com Principal Engineer, Modeling Engineering Lead, Micron Technology, Inc. 8000 S. Federal Way Mail Stop: 01-711 Boise, ID 83707-0006 LIBRARIAN: Anders Ekholm (46) 10 714 27 58, Fax: (46) 8 757 23 40 ibis-librarian@eda.org Digital Modules Design, PDU Base Stations, Ericsson AB BU Network Färögatan 6 164 80 Stockholm, Sweden WEBMASTER: Mike LaBonte mikelabonte@eda.org IBIS-AMI Modeling Specialist, Signal Integrity Software 6 Clock Tower Place Maynard, MA 01754 POSTMASTER: Mike LaBonte mikelabonte@eda.org IBIS-AMI Modeling Specialist, Signal Integrity Software 6 Clock Tower Place Maynard, MA 01754 This meeting was conducted in accordance with ANSI guidance. The following e-mail addresses are used: majordomo@eda.org In the body, for the IBIS Open Forum Reflector: subscribe ibis In the body, for the IBIS Users' Group Reflector: subscribe ibis-users Help and other commands: help ibis-request@eda.org To join, change, or drop from either or both: IBIS Open Forum Reflector (ibis@eda.org) IBIS Users' Group Reflector (ibis-users@eda.org) 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 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. ibis-bug@eda.org To report ibischk parser BUGs as well as tschk2 parser BUGs. The BUG Report Form for ibischk resides along with reported BUGs at: http://www.eda.org/ibis/bugs/ibischk/ http://www.eda.org/ibis/bugs/ibischk/bugform.txt The BUG Report Form for tschk2 resides along with reported BUGs at: http://www.eda.org/ibis/tschk_bugs/ http://www.eda.org/ibis/tschk_bugs/bugform.txt icm-bug@eda.org To report icmchk1 parser BUGs. The BUG Report Form resides along with reported BUGs at: http://www.eda.org/ibis/icm_bugs/ http://www.eda.org/ibis/icm_bugs/icm_bugform.txt To report s2ibis, s2ibis2 and s2iplt bugs, use the Bug Report Forms which reside at: http://www.eda.org/ibis/bugs/s2ibis/bugs2i.txt http://www.eda.org/ibis/bugs/s2ibis2/bugs2i2.txt http://www.eda.org/ibis/bugs/s2iplt/bugsplt.txt Information on IBIS technical contents, IBIS participants and actual IBIS models are available on the IBIS Home page: http://www.eda.org/ibis Check the IBIS file directory on eda.org for more information on previous discussions and results: http://www.eda.org/ibis/directory.html Other trademarks, brands and names are the property of their respective owners. IBIS – SAE STANDARDS BALLOT VOTING STATUS I/O Buffer Information Specification Committee (IBIS) |Organization |Interest |Standar|October|Novembe|Novembe|Novembe| | |Category |ds |11, |r 1, |r 15, |r 19, | | | |Ballot |2013 |2013 |2013 |2013 | | | |Voting | | | | | | | |Status | | | | | |Agilent |User |Active |X |X |X |X | |Technologies | | | | | | | |Altera |Producer |Inactiv|X |X |- |- | | | |e | | | | | |ANSYS |User |Active |- |- |X |X | |Applied Simulation|User |Inactiv|- |- |- |- | |Technology | |e | | | | | |Cadence Design |User |Active |X |X |X |X | |Systems | | | | | | | |Ericsson |Producer |Active |- |- |X |X | |Foxconn Technology|Producer |Inactiv|- |- |- |X | |Group | |e | | | | | |Huawei |Producer |Inactiv|- |- |X |- | |Technologies | |e | | | | | |IBM |Producer |Inactiv|- |X |- |- | | | |e | | | | | |Infineon |Producer |Inactiv|- |- |- |- | |Technologies AG | |e | | | | | |Intel Corp. |Producer |Active |X |X |X |X | |IO Methodology |User |Active |X |- |X |X | |LSI |Producer |Inactiv|X |X |- |- | | | |e | | | | | |Maxim Integrated |Producer |Inactiv|- |- |- |- | |Products | |e | | | | | |Mentor Graphics |User |Inactiv|X |X |- |- | | | |e | | | | | |Micron Technology |Producer |Inactiv|X |X |- |- | | | |e | | | | | |Signal Integrity |User |Inactiv|X |X |- |- | |Software | |e | | | | | |Synopsys |User |Inactiv|- |- |X |- | | | |e | | | | | |Teraspeed |General |Inactiv|X |X |- |- | |Consulting |Interest |e | | | | | |Toshiba |Producer |Inactiv|- |- |- |- | | | |e | | | | | |Xilinx |Producer |Inactiv|- |- |- |- | | | |e | | | | | |Zuken |User |Inactiv|- |- |- |- | | | |e | | | | | Criteria for Member in good standing: • Must attend two consecutive meetings to establish voting membership • Membership dues current • Must not miss two consecutive Meetings Interest categories associated with SAE ballot voting are: • Users - Members that utilize electronic equipment to provide services to an end user. • Producers - Members that supply electronic equipment. • General Interest - Members are neither producers nor users. This category includes, but is not limited to, Government, regulatory agencies (state and federal), researchers, other organizations and associations, and/or consumers.