IBIS Macromodel Task Group Meeting date: 21 February 2023 Members (asterisk for those attending): Achronix Semiconductor: Hansel Dsilva Amazon: John Yan ANSYS: * Curtis Clark * Wei-hsing Huang Aurora Systems: * Dian Yang Cadence Design Systems: Ambrish Varma * Jared James Google: Hanfeng Wang GaWon Kim Intel: Michael Mirmak * Kinger Cai Chi-te Chen Alaeddin Aydiner Keysight Technologies: Fangyi Rao Majid Ahadi Dolatsara Ming Yan Radek Biernacki 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 Yifan Ding Rivos Yansheng Wang SAE ITC Michael McNair Siemens EDA (Mentor): * Arpad Muranyi Teraspeed Labs: Bob Ross Waymo: Zhiping Yang Zuken USA: * Lance Wang The meeting was led by Arpad Muranyi. Curtis Clark took the minutes. -------------------------------------------------------------------------------- Opens: - None. ------------- Review of ARs: - Kinger to send out draft9 of the SPIM BIRD containing changes reviewed and discussed in the previous meeting. - Done. -------------------------- Call for patent disclosure: - None. ------------------------- Review of Meeting Minutes: Arpad asked for any comments or corrections to the minutes of the February 14th meeting. Kinger moved to approve the minutes. Jared seconded the motion. There were no objections. -------------- New Discussion: Standard Power Integrity Model (SPIM) BIRD draft: Kinger reported that he had received no new feedback since sending out draft9. Kinger reviewed the changes in draft9, which were enumerated in the email sent out with it. Arpad and Kinger asked everyone to read the draft and provide feedback. PSIJ Sensitivity BIRD draft: Kinger had sent out draft6 the previous week. Arpad had replied with a draft6_AM containing additional minor editorial fixes, and Kinger used that as the starting point for the review and discussion. Kinger noted that the Solution Requirements section had been converted to table form, as was done for the SPIM BIRD draft. Arpad suggested that the [PSIJ Voltage List] keyword should also be mentioned in the table. Kinger agreed. Kinger had added a definition of the acronym PPA (performance power area), per Arpad's suggestion. In the [PSIJ Sensitivity Group] Usage Rules, Arpad asked what was meant by saying that the interface was designed in a "multiplexer architecture." Kinger said it was referring to cases in which the same Silicon could be used for different standards. For example, DDR4 and LPDDR4 might be supported by the same controller. Jared agreed with Arpad that "multiplexer" sounded more like a circuit type. Jared suggested "multi-standard" instead. Randy suggested that this sounded like an FPGA for which the I/O could support multiple standards. Dian suggested, "I/O can be configured to support multiple standards." The group converged on: "I/O is configurable for supporting multiple interface standards." Also in the [PSIJ Sensitivity Group] Usage Rules, Arpad noted the text stating that the [PSIJ Sensitivity Group] / [End PSIJ Sensitivity Group] pair could appear "multiple times in one .ibs file". Arpad asked whether this keyword pair is scoped under [Component]. Kinger said he wasn't sure, and he asked for an example to illustrate the [Component] keyword. Randy said a [Component] is a packaged device. He gave a DRAM example. He said you might have a x8 DRAM and its BGA package in one [Component]. Another [Component] in the same .ibs file might be a x16 DRAM and its package. Randy said the x8 and x16 [Component]s might share some [Model]s and might have some [Model]s that were unique to each. Kinger then confirmed that the [PSIJ Sensitivity Group] pairs should be scoped by [Component]. He said the PSIJ sensitivity and the rails themselves might be different for the x8 and x16 [Component]s. Kinger said you could have multiple [PSIJ Sensitivity Group] pairs under the same [Component] if, for example, the [Component] supported DDR4 and LPDDR4. Randy said the language had to be refined to state that the keyword pair could appear multiple times, but the name of each group had to be unique within each [Component]. Randy and Arpad suggested this BIRD follow the example set by the [Interconnect Model Group] keywords. Randy said the Example for [PSIJ Sensitivity Group] didn't make sense. He asked if it was missing the [End PSIJ Sensitivity Group] keywords. Kinger agreed and said the Example had duplicate start keywords instead of the end keywords (cut & paste type error). Kinger fixed the example. Randy asked a more general question about the simulation flow. He asked how the EDA tool was expected to use the [PSIJ Sensitivity Group] information in any particular simulation. Kinger said the intent of the proposal was a novel methodology to account for the effect of the total noise on each of the power rails and its contribution to jitter. For example, for a given power rail the simulator would perform a PI simulation to get the noise on that rail. This could be converted to frequency domain via FFT, then multiplied by the [PSIJ Sensitivity] data for that rail to get a Jitter spectrum, then converted to a time domain peak-peak Jitter via IFFT. This would provide the deterministic jitter contribution from that particular power rail. Arpad asked if the intent was then to have the simulator apply the peak-peak jitter contributions to the edges of the stimulus waveform for an IBIS or IBIS-AMI model in an SI simulation. Kinger said the deterministic jitter would be applied as a post processing step to the final eye diagram. Randy said that what Kinger described was essentially calculation of the value to be used in the existing IBIS-AMI Reserved Parameter Tx_Dj. Kinger said that instead of merely giving the platform designer an overall noise budget, as is commonly the case today, this proposal gives noise sensitivity information to the designer and allows them more freedom in design. - Curtis: Motion to adjourn. - Randy: Second. - Arpad: Thank you all for joining. AR: Kinger to send out draft7 of the PSIJ Sensitivity BIRD containing changes reviewed and discussed in today's meeting. ------------- Next meeting: 28 February 2023 12:00pm PT ------------- IBIS Interconnect SPICE Wish List: 1) Simulator directives