IBIS Macromodel Task Group Meeting date: 13 July 2010 Members (asterisk for those attending): Adge Hawes, IBM * Ambrish Varma, Cadence Design Systems Anders Ekholm, Ericsson * Arpad Muranyi, Mentor Graphics Corp. Barry Katz, SiSoft * Bob Ross, Teraspeed Consulting Group Brad Brim, Sigrity Brad Griffin, Cadence Design Systems Chris Herrick, Ansoft Chris McGrath, Synopsys Danil Kirsanov, Ansoft David Banas, Xilinx Deepak Ramaswany, Ansoft Donald Telian, consultant Doug White, Cisco Systems * Eckhard Lenski, Nokia-Siemens Networks Eckhard Miersch, Sigrity Essaid Bensoudane, ST Microelectronics * Fangyi Rao, Agilent Ganesh Narayanaswamy, ST Micro Gang Kang, Sigrity Hemant Shah, Cadence Design Systems Ian Dodd, consultant Jerry Chuang, Xilinx Joe Abler, IBM * John Angulo, Mentor Graphics John Shields, Mentor Graphics * Ken Willis, Sigrity Kellee Crisafulli, Celsionix * Kumar Keshavan, Sigrity Lance Wang, Cadence Design Systems Luis Boluna, Cisco Systems * Michael Mirmak, Intel Corp. * Mike LaBonte, Cisco Systems Mike Steinberger, SiSoft Mustansir Fanaswalla, Xilinx Patrick O'Halloran, Tiburon Design Automation Paul Fernando, NCSU Pavani Jella, TI * Radek Biernacki, Agilent (EESof) Randy Wolff, Micron Technology Ray Komow, Cadence Design Systems Richard Mellitz, Intel Richard Ward, Texas Instruments Samuel Mertens, Ansoft Sam Chitwood, Sigrity Sanjeev Gupta, Agilent Scott McMorrow, Teraspeed Consulting Group Shangli Wu, Cadence Design Systems Sid Singh, Extreme Networks Stephen Scearce, Cisco Systems Steve Kaufer, Mentor Graphics Steve Pytel, Ansoft Syed Huq, Cisco Systems Syed Sadeghi, ST Micro Ted Mido, Synopsys Terry Jernberg, Cadence Design Systems * Todd Westerhoff, SiSoft Vladimir Dmitriev-Zdorov, Mentor Graphics Vikas Gupta, Xilinx Vuk Borich, Agilent * Walter Katz, SiSoft Wenyi Jin, LSI Logic Zhen Mu, Mentor Graphics ------------------------------------------------------------------------ Opens: - Arpad asked participants to find ways to help close the AMI topic -------------------------- Call for patent disclosure: - No one declared a patent. ------------- Review of ARs: - Arpad: Write parameter passing syntax proposal (BIRD draft) for *-AMS models in IBIS that is consistent with the parameter passing syntax of the AMI models - TBD: Propose a parameter passing syntax for the SPICE - [External ...] also? - TBD - Arpad: Review the documentation (annotation) in the macro libraries. - Deferred until a demand arises or we have nothing else to do ------------- New Discussion: Arpad: The latest IBIS-ISS document has been posted: - Michael M showed the specification - Michael M: Both marked-up and clean copies are posted - There is a Statement of Changes - We need to work on line continuations - There was a request for string parameters - Everything is mentioned only once - This leaves some items scattered throughout Todd showed a presentation IBIS-AMI Flows: - Slide 4: - In 2006/10 we had a time domain flow only in mind - Kumar: Statistical analysis will be supported if the EQ is in Init - Todd: Yes - Slide 5: - In 2007/10 we added Init_Returns_Impulse and GetWave_Exists - Slide 6: - We ran into interpretation conflicts, added Use_Init_Output 2008/05 - With IBIS 5.0 2008/08 we sort of enabled statistical simulation - Slide 9: - The potential for split Init/GetWave models made us complicate things - There are no known models that do this - Ken: There are really only 2 possible rows in this table - Walter: You always need Init to initialize GetWave - Kumar: What is dual and what is split? - Todd: With split you need both Init/GetWave chained together - With dual Init is approximate, GetWave is the accurate version - Ken: Dual will fall into one of the 2 rows anyway - Slide 10: - These 9 cases are agreed upon, out of the 16 - Slide 12: - You always have to process Init somehow - This flow never changes - Slide 14: - The simulator can create "LTI GetWave" when the model has no GetWave - Slide 15: - hXEI(t) is not usually needed - Fangyi: The red box is the main confusion - Michael M: Struggling with the notation - Kumar: Also struggling with the notation - Arpad: We have been using this notation for a while - Radek: It is misleading, should be TTA - Slide 16: - Todd: Walter pointed out that RX pre-optimization requires this - Fangyi: #2 and #3 are equivalent - Todd: Yes, in some ways - Slide 17: - We are back to needing a spec change - Arpad: Most people will update their simulators - Slide 17: - Todd: We need a way to isolate hREI(t) or to pass in what we have - Kumar: This is to make optimization less dependent on impulse response? - Todd: A later slide may help explain - Slide 18: - The simulator has to decide: If GetWave does not exist what do I convolve? - The RX Init-only model still may optimize - Ambrish: The RX model could recommend to the user whether to use optimization - Kumar: The EDA tool could decide that - The user could do it - Todd: This is the flow we believe exists today - Slide 19: - Forgot to mention a BIRD on this slide - Will update and send to Mike for posting - Slide 20: - Ambrish: If there is both TX GetWave and Init they would use GetWave only - Todd: This is case 7 on slide 10 - Simulators do this already - Kumar: Then it is solved - Ambrish: But it is not in the spec - Walter: I will send the AMI Flow and Impulse Response Return BIRDs - We need to get closure - Suggested amendments could be recommended with BIRD submission - Fangyi: This is different from Arpad's BIRD? - Walter: Right - Ambrish: If we agree there is no new reserved parameter we are done today - Walter: The open forum should decide that - Todd: We are trying to develop a simpler way of expressing this - Arpad: It was 14 against 2, now it is 1 against 8 - The problem case is still the same - Todd: I'm trying to get it on one sheet - Arpad: There are 3 ways to solve this issue - In March we voted to stay away from deconvolution - Ambrish: We need to rule out the reserved parameter - We can't do #7 - Walter: This should be presented in writing - We can discuss it next week - Todd: LTI GetWave models do exist - This is a solved problem, through deconvolution - Don't want to rule out that flow - Arpad: Three choices: - Deconvolution - A new parameter - Matrix changes - Walter: Would like to have new BIRD considered first - Todd: I will change slide 17 to reflect Arpad's proposal - Also make a change for Radek's comment - Bob: This group needs to decide before the open forum sees it AR: Todd send update presentation to Mike for posting AR: Walter send new BIRD draft to Mike for posting Next meeting: 20 July 2010 12:00pm PT -------- IBIS Interconnect SPICE Wish List: 1) Simulator directives