IBIS Macromodel Task Group Meeting date: 12 Feb 2013 Members (asterisk for those attending): Agilent: Fangyi Rao * Radek Biernacki Altera: * David Banas Julia Liu Hazlina Ramly Andrew Joy Consulting: Andy Joy ANSYS: Samuel Mertens * Dan Dvorscak * Curtis Clark Steve Pytel Luis Armenta Arrow Electronics: Ian Dodd Cadence Design Systems: Terry Jernberg * Ambrish Varma Feras Al-Hawari Brad Brim Kumar Keshavan Ken Willis Cavium Networks: Johann Nittmann Celsionix: Kellee Crisafulli Cisco Systems: Ashwin Vasudevan Syed Huq Ericsson: Anders Ekholm IBM: Greg Edlund Intel: Michael Mirmak Maxim Integrated Products: Mahbubul Bari Hassan Rafat Ron Olisar Mentor Graphics: * John Angulo Zhen Mu * Arpad Muranyi Vladimir Dmitriev-Zdorov Micron Technology: Randy Wolff Justin Butterfield NetLogic Microsystems: Ryan Couts Nokia-Siemens Networks: Eckhard Lenski QLogic Corp. James Zhou SiSoft: Walter Katz Todd Westerhoff Doug Burns * Mike LaBonte Snowbush IP: Marcus Van Ierssel ST Micro: Syed Sadeghi Teraspeed Consulting Group: Scott McMorrow * Bob Ross TI: Casey Morrison Alfred Chong Vitesse Semiconductor: Eric Sweetman Xilinx: Mustansir Fanaswalla Ray Anderson The meeting was led by Arpad Muranyi ------------------------------------------------------------------------ Opens: - None -------------------------- Call for patent disclosure: - None ------------- Review of ARs: - Ambrish email reflector regarding BIRD 147 status - This may not have been an assigned AR from last week ------------- New Discussion: Interconnect Task Group report: - No report Arpad showed a reorganized list of high priority BIRDs to work on - Arpad: For AMI our major topics are redriver, backchannel, and dependency table - Arpad recapped the nature of the various analog BIRDs (10 of them) - Bob: We were supposed to hear about the Agilent/SiSoft proposal - Radek: It is mostly about using touchstone for the on-die model - It is not a general solution - Arpad: Walter described it as using analog parameters in the AMI file - We may want to implement both the press release solution on other BIRDs - We could work on replacing our legacy IBIS and it might replace the BIRD 116 family - The question is if we need an interim solution while working on it - Mike: BIRD 153 probably would go away if we created a new IBIS - Bob: We have too many BIRDs - The AMI list is shorter and more tractable - About BIRD 153, overloading IBIS with another format would not be good - Arpad: The parameter tree could be in an external file - Bob: It might be better to go with something like EMD, which is more like IBIS - Radek: But we need to solve the parameter passing issue - IBIS-ISS is waiting to be used, but there is no way to link to it - It is most important right now to solve the analog model problem - We have not said how to derive the impulse response - Arpad: We decided to leave that up to vendors - Radek: This allows vendors to derive responses that don't work correctly with models - Ambrish: Should that be in the spec or separate? - Radek: In the spec - Arpad and Bob agreed - There was discussion about the nature of impulse responses - David: If we were to ever get clock to out delay we would use the standard delay technique - It is a bad idea for EDA tools to normalize the impulse response - We should prescribe a reference flow in section 10 - Tools are free to implement any method but they have to get the same results - Ambrish: We should not do that - Radek: It should be fine as long as people agree the reference flow produces an expected result - Ambrish: We could put the impulse response in the algorithm model - Arpad: Greg was suggesting only that the model CALCULATE the impulse response - Radek: It is not advisable to do that - Arpad: The DLL could calculate it, but why burden the model? - Ambrish: We are jumping the gun and discussing BIRD 122 already Arpad: We need to schedule topics for the next few meetings: - Ambrish: We should discuss BIRDs 116 to 118 - The press release discussed those - Arpad: Walter has an AR to introduce his proposal next week - We were going to have important BIRD work done by the next IBIS release - Bob: It might be a problem getting into 6.0, maybe it would be 6.1 - Arpad: Our new approach was to have scheduled releases - Bob: We should resolve all AMI BIRDs - Ambrish: Our big issue is what to have for an analog BIRD - [External Model] should be workable - Bob: 3 vendors support it and 3 don't - Arpad: Walter has an issue with that approach, and there may be ways to fix it - Ambrish: We want use s-params, that has worked well - Radek: We were thinking of not using [External Model], but something similar - The problem with [External Model] is that it is a total replacement - Arpad: An AMI subckt would work well using IBIS-ISS - Radek: Agree - Mike: We might get somewhere by trimming down BIRDs that have too much - Mostly we need to vote down some BIRDs - Bob: We have been voting on amendments to BIRDs - Arpad: We might create a simplification to the [External Model] approach - Bob: Do we need a long term solution or would short term do? - Ambrish: We should not take shortcuts - Mike: The longer term general solutions have the problem that [Model] is not differential - Ambrish: The problem is that vendors are not making models - Arpad: Walter believes EMD solves this, but that is a gobbledlygook approach Arpad: Hopefully we can resume redriver discussions with Fangyi on board - Radek: He will be back next week - Ambrish: We can discuss backchannel soon - Arpad: We should reserve half the meeting for a proposal from Walter ------------- Next meeting: 19 Feb 2013 12:00pm PT Next agenda: 1) Task list item discussions ------------- IBIS Interconnect SPICE Wish List: 1) Simulator directives