IBIS Macromodel Task Group Meeting date: 03 March 2009 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 * David Banas, Xilinx Donald Telian, consultant Doug White, Cisco Systems * Eckhard Lenski, Nokia-Siemens Networks Essaid Bensoudane, ST Microelectronics Fangyi Rao, Agilent Ganesh Narayanaswamy, ST Micro Gang Kang, Sigrity Hemant Shah, Cadence Design Systems Ian Dodd, Agilent Jerry Chuang, Xilinx Joe Abler, IBM * John Angulo, Mentor Graphics John Shields, Mentor Graphics Ken Willis, Cadence Design Systems 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 Comeau, Cadence Design Systems Richard Mellitz, Intel Richard Ward, Texas Instruments Sam Chitwood, Sigrity Sanjeev Gupta, Agilent Shangli Wu, Cadence Design Systems Sid Singh, Extreme Networks Stephen Scearce, Cisco Systems Steve Pytel, Ansoft Syed Huq, Cisco Systems Syed Sadeghi, ST Micro Terry Jernberg, Cadence Design Systems Todd Westerhoff, SiSoft Vladimir Dmitriev-Zdorov Vikas Gupta, Xilinx Vuk Borich, Agilent * Walter Katz, SiSoft Zhen Mu, Cadence Design Systems ------------------------------------------------------------------------ Opens: Arpad: There was a conversation about s-params on the si-list recently - Scott McMorrow asked why we would want to restrict s-params - Michael M: We must decide how much to say about quality, above and beyond format - Bob: Tools try to take care of these problems Michael M: 2 years ago at DesignCon scope makers were interested in an AMI-like approach - Walter: We did not ask scope makers to join us this time - They do a channel TDR to get equivalent impulse response - They have internal RX models - Michael M: We should invite them to join a meeting -------------------------- Call for patent disclosure: - No one declared a patent. ------------- Review of ARs: - Todd: Start a BIRD for IBIS s-params - TBD - 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 - 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: Continued discussion of IBIS Interconnect SPICE: - Walter showed his IBIS Interconnect SPICE document - Page 12: - This call has N nodes plus a reference node - Assuming the reference node is DC - Params: MNAME (model name), TYPE=s or y - Only FBASE and FMAX are commonly used - This seems to be required to make HSPICE work - Arpad: What is the order of precedence for instance vs. model params? - Radek: Do FBASE and FMAX truncate the file data? - We have to look into this - Randy: They are frequency points used for transient analysis - Arpad: Use of a single reference node makes all other ports single ended - Does this limit us? - Walter: One should be fine for what we are doing - Bob: Any port can be used as a reference node - Radek: That does not sound right - Michael M: Are we sure each port is a node? - Bob: The manual says this - Michael M: There are at least 3 terminal arrangements - HSPICE seems to use 2: - One reference for all nodes - One reference for each node - Bob: It may be best to copy the HSPICE description verbatim - Walter: We may want to limit how we use it - Michael M: We can invite Synopsys to join us to explain it - Mike L: Can TSTONFILE be used on the S call to bypass .MODEL? - Walter: Don't think so - Arpad: It would be a nice feature, maybe we should do it - Walter: Maybe as a next step - Page 13: - The W element N= param is redundant - It can be determined from the number of terminals - HSPICE recommends not using RLCGFILE (deprecated) - NODEMAP is used when W elem calls an s-param - We have to know what the units of the model are to call it correctly - It could be inches, meters, whatever - TABLE model syntax is more complicated - It is similar to W model in ICM - Michael M: Suggest: - RLCG and TABLE .MODEL allow you to change order of matrices - The RLGC file has a more rigid format, easy to get wrong - How do we handle interpolation? - We should exclude geometric models - Randy: Would like to support RLGCFILE because models exist - Mike L: Are Rs and Gd still used? - Walter: Yes, quite accurate for stripline - Radek: Agree - Arpad: Does W have to support S format? - Radek: It is OK if only the S element has this - Radek: SP model format used by tabular format is very flexible - This is LMODEL, CMODEL, RMODEL, GMODEL - This may be difficult to use, goes far beyond W element - Page 6: - We have to verify the list of functions - Arpad: ** can be used for ^ - Walter: In HSPICE .PARAM can contain a node, but not here - Arpad: Not so sure, params are supposed to be static - Maybe it would use the DC operating point - This needs to be verified - Page 9: - Not all EFGH elements support all options shown - Page 10: - Bob: We should drop Foster Pole-Residue form - Radek: This is useful - We will keep it AR: Todd invite Synopsys to join us for a syntax review Arpad: We should add the details to make this a complete manual - Walter that is the next step, but it is not trivial - Would be better to have a better source than PDF - Arpad: Do we want to use the HSPICE format? - Walter: We should use HSPICE format - Bob: We should show that we are not hiding the origin of the document - We will need the source documents - Walter: Would prefer to just highlight the sections we are using - Mike L: There are PDF converters to other formats - Walter: It's easier to have it already in coherent document format AR: Walter send updated IBIS Interconnect SPICE proposal to Mike L for posting AR: Mike L post updated IBIS Interconnect SPICE proposal Next meeting: 10 March 2009 12:00pm PT -----------