IBIS Macromodel Task Group Meeting date: 8 August 2023 Members (asterisk for those attending): Achronix Semiconductor: Hansel Dsilva Amazon: John Yan ANSYS: Curtis Clark * Wei-hsing Huang Aurora System: * Dian Yang Cadence Design Systems: * Ambrish Varma Jared James Google: Hanfeng Wang GaWon Kim Intel: * Michael Mirmak * Kinger Cai * Chi-te Chen Liwei Zhao Keysight Technologies: * Fangyi Rao Majid Ahadi Dolatsara Stephen Slater Ming Yan Rui Yang Marvell: Steve Parker Mathworks (SiSoft): Walter Katz Graham Kus Micron Technology: Justin Butterfield Missouri S&T: Chulsoon Hwang Yifan Ding Zhiping Yang Rivos: Yansheng Wang SAE ITC: Michael McNair Siemens EDA (Mentor): * Arpad Muranyi * Randy Wolff Teraspeed Labs: * Bob Ross Zuken USA: * Lance Wang The meeting was led by Arpad Muranyi. Randy Wolff took the minutes. -------------------------------------------------------------------------------- Opens: - None. ------------- Review of ARs: Kinger: Send out draft14 of the PSIJ Sensitivity proposal including more feedback from Fangyi and the ATM meeting. - Done. -------------------------- Call for patent disclosure: - None. ------------------------- Review of Meeting Minutes: Arpad asked for any comments or corrections to the minutes of the July 25th meeting. Michael moved to approve the minutes. Dian seconded the motion. There were no objections. -------------- New Discussion: PSIJ frequency domain modeling BIRD draft: Kinger noted the majority of feedback from Fangyi was incorporated in Draft 13. Changes were in blue text and reviewed in ATM. In draft 14, he incorporated another feedback item from Fangyi. This adds phase of the sensitivity value on pages 10 and 11. Randy asked why the phase was 0-360 instead of +/- 180 degrees. Kinger noted the range is the same and he preferred the values to remain all positive. Kinger asked if the BIRD was ready to submit to the Open Forum. Fangyi did not have any further comments on the BIRD. Ambrish said he would circulate the draft for review. Michael motioned to submit the BIRD draft to the Open Forum. Arpad seconded the motion. There were no objections. Kinger to submit the BIRD draft to Lance to get a BIRD number assigned [AR] [AMI Test Load] and [AMI Test Data]: Michael prepared a draft 3 for the meeting. No changes were made to [AMI Test Data]. [Waveform] adds in AMI_outputs_file and Clock_file subparameters, and the AMI_inputs_file parameter renamed from TX_AMI_parameters_file. The stimulus file and waveform file are changed in format to be vectors, removing the time column. They are CSV files but rely on the regular time step and starting time of 0. The AMI_inputs_file and AMI_outputs_file remove CSV format and use a parameter tree syntax similar to the .ami file format. Michael noted he questions if the Direction subparameter is needed for both [Waveform] and its parent keyword [AMI Test Data]. Michael stated there is a problem with usage of .ami format creating some potential confusion. Ambrish said some settings could be in a different tree, including Sample_interval, Symbol_time, and Number_of_rows. Michael said those parameters would need to be in a separate file. Fangyi said if you placed the parameters in a separate header that would be ok. Arpad suggested a separate branch for these parameters. Michael liked this suggestion. Ambrish asked why there was a value after root name. Michael noted this was a mistake. Fangyi asked about the significance of the root name. Michael noted this should match what is expected of the AMI functions and should match the root name output from the AMI functions. Bob was concerned about using the CSV format, questioning if we were going to publish the official CSV format such as from Adobe. Michael noted whether we have space-delimited or comma-delimited, we'll have to make notes about the expected format. Arpad asked what format we have for waveform data in IBIS-AMI. Michael thought they were space-delimited. Bob noted another variation consistent with IBIS-AMI would be the Table format. Michael asked about scaling of values, using suffixes defined in IBIS. Arpad noted scaling is not used in IBIS-AMI. Bob said we should only use base units. Michael wondered if anyone tested having suffixes (scaling) in IBIS-AMI data. Bob though this should be illegal. Fangyi noted on page 3 a Model_corner parameter. How is it used? Michael said we could remove it if the Corner AMI parameter is passed along. Fangyi said Direction is useful if an AMI model is an I/O type. Fangyi noted for time domain, need to call AMI_Init first, requiring another Stimulus_file for the input impulse matrix. Michael said we could require a pointer to an input to AMI_Init. Fangyi said we don't care about the output impulse response from Init, but we do need to call AMI_Init before AMI_GetWave. We need to think about how to pair these functions. Fangyi asked if for an Rx model we need a clock_times output file. Michael said there would need to be a second output file for this. On page 7, Fangyi asked what was special about the first column. Michael needs to remove this reference. Fangyi asked if, in time domain, the number of rows shall equal wave_size*integer. Arpad said each AMI_GetWave call could have a different block size. Could this cause problems? Fangyi said for this BIRD we could assume there is a fixed wave_size. Arpad said you'd need to state this. Michael thought wave_size in the current spec is poorly written. Michael said we need to define the number of blocks. Fangyi requested to clarify the meaning of wave_size. Arpad asked what is the purpose of wave_size. Fangyi said it is how long each block is, not how long the waveform is. It's required in this BIRD. Michael said this structure doesn't allow an output waveform with varying block sizes. Arpad noted this happens in reality. Michael said this requires the stimulus be an integer multiplier of block size. Fangyi commented on page 6, asking what if Rx_Use_Clock_Input="Wave". Michael will have to add this in. Fangyi noted for Rx_Use_Clock_Input="Wave", the length of Clock_file should be the same length as the waveform. Further discussion on this point clarified that the Clock_file vector would contain only one clock tick per UI whereas the waveform would have many samples per UI. Fangyi noted the AMI_outputs_file needs more attention. Ambrish asked if Michael had thought about transmitter models that require an impulse response. Michael noted this case is covered. Fangyi added that he'd noticed the need for another file for an impulse response input. - Ambrish: Motion to adjourn. - Michael: Second. - Arpad: Thank you all for joining. New ARs: Kinger to submit the BIRD draft to Lance to get a BIRD number assigned [AR] ------------- Next meeting: 15 August 2023 12:00pm PT ------------- IBIS Interconnect SPICE Wish List: 1) Simulator directives