IBIS Macromodel Task Group Meeting date: 14 September 2021 Members (asterisk for those attending): Achronix Semiconductor: Hansel Dsilva Amazon: John Yan ANSYS: * Curtis Clark * Wei-hsing Huang Cadence Design Systems: * Ambrish Varma Ken Willis Jared James Google: Zhiping Yang Intel: Michael Mirmak Kinger Cai Alaeddin Aydiner Keysight Technologies: * Fangyi Rao Radek Biernacki Ming Yan Todd Bermensolo * Rui Yang Luminous Computing David Banas Marvell Steve Parker Mathworks (SiSoft): Walter Katz Mike LaBonte Micron Technology: * Randy Wolff * Justin Butterfield Missouri S&T Chulsoon Hwang Siemens EDA (Mentor): * Arpad Muranyi Teraspeed Labs: * Bob Ross Zuken USA: * Lance Wang The meeting was led by Arpad Muranyi. Curtis Clark took the minutes. -------------------------------------------------------------------------------- Opens: - None. ------------- Review of ARs: - Chulsoon to email his presentation to ATM. - Done. -------------------------- Call for patent disclosure: - None. ------------------------- Review of Meeting Minutes: Arpad asked for any comments or corrections to the minutes of the September 14th meeting. Randy moved to approve the minutes. Lance seconded the motion. There were no objections. ------------- New Discussion: PSIJ modeling: Randy noted that Micron is looking at some buffers to characterize PSIJ and see if they can provide recommendations for the BIRD Chulsoon may create. He said we may need to more precisely specify how you measure the [PSIJ] value (test loads, voltage levels, etc.). Bob asked whether it might make sense to have [PSIJ] values under different load conditions, perhaps the load conditions for the various rising and falling waveforms. Randy said he expects to be able to share some data and assemble a presentation in the future. He said they had characterized one driver and looked at the linearity of the PSIJ value. He said it would be interesting to see how well a single PSIJ value fits the full PSIJ plots they had created. Arpad noted that Walter had suggested alternate uses of the [PSIJ] keyword data, for example, the EDA tool could shift the edges of the stimulus waveform input to Tx GetWave. Arpad asked whether we should consider adding text to that effect or should deal with that as a separate AMI Reserved Parameter. Bob thought we'd want to keep them separate. Randy said it was an interesting question, and you might want to put the same measurement value in both places. Bob said it might not be obvious how to map information from a PSIJ keyword with typ/min/max, etc., into use in AMI. DDR5 Modeling updates: Arpad asked Randy and Justin about any updates/issues. Justin said they are providing some early DDR5 AMI models. He said things are working, but they are eagerly awaiting the release of 7.1. He said once EDA tools support 7.1 features we will be okay for now. GDDR6x update: Randy said he had nothing new to report. He said he had given Walter some additional details on the GDDR6x buffer so he could think about AMI improvements that might be useful. Randy said he wanted to do more characterization of the equalization in the GDDR6x Tx and see how badly it breaks any AMI assumptions. Randy said it will probably be a while before he has a new update. Review of Tabled Topics List: Item 10 - Old Redriver flow proposals/BIRDS: The group decided this could be removed, as we don't expect to revisit any of these given the progress of BIRD211.3. Item 13 - Other DDR5 related topics: Bob suggested we keep this topic. Randy said EDA tools have different ways of dealing with rise/fall asymmetry. He said that as they've tested out their DDR5 models in various tools they've observed different waveforms passed into GetWave. Arpad said he'd wondered whether we need to extend AMI so that it has two IRs or possibly a pulse response. Ambrish said he thought we had settled this and agreed that rise/fall asymmetry could be handled by tools without changing AMI. The group agreed this topic could stay on the list. Item 14 - New BIRDs from Editorial Task Group? Bob said these are still important topics, but addressing them would span all of IBIS, and they hadn't had time. The group agreed this could stay on the list. Item 15 - Missing min/max data? Arpad said this still and issue, but he hadn't spent any more time on it. The group agreed this could stay on the list. Pending BIRDs awaiting discussion: Bob suggested that we remove the "TBD" entry and leave the other two BIRDs there on the list until the Open Forum votes them down. The group agreed. Topic bin list: The fourth item on the list, referencing issues, was moved to become entry e of item 14 in the Tabled Topics. All other items were left in place. - Ambrish: Motion to adjourn. - Curtis: Second. - Arpad: Thank you all for joining. ------------- Next meeting: 28 September 2021 12:00pm PT ------------- IBIS Interconnect SPICE Wish List: 1) Simulator directives