IBIS Macromodel Task Group Meeting date: 3 December 2019 Members (asterisk for those attending): ANSYS: Dan Dvorscak Curtis Clark Cadence Design Systems: Ambrish Varma Ken Willis Kumar Keshavan Intel: Michael Mirmak Keysight Technologies: Fangyi Rao * Radek Biernacki Ming Yan Todd Bermensolo Mentor, A Siemens Business: * Arpad Muranyi Micron Technology: * Randy Wolff * Justin Butterfield SiSoft (Mathworks): * Walter Katz * Mike LaBonte SPISim: * Wei-hsing Huang Teraspeed Labs: * Bob Ross The meeting was led by Arpad Muranyi. Justin Butterfield took the minutes. -------------------------------------------------------------------------------- Opens: - Upcoming meeting schedule: - Arpad proposed to cancel the meetings on December 24 and 31 for the Holidays and on January 28 for DesignCon. ------------- Review of ARs: - Randy and Michael M. to invite DDR memory and controller vendors to comment on new protocols. - In progress. - Bob to update BIRD197.6_draft_3 based on the discussion in the meeting last week. - Arpad reported this was done. -------------------------- Call for patent disclosure: - None. ------------------------- Review of Meeting Minutes: Arpad suggested to review the minutes next week to give more time to review. --------------- New Discussion: Arpad reviewed that two weeks ago we planned a vote on the subject of enabling Back Channel Interface in statistical mode. List of options to choose from in the vote: 1. AMI_Impulse 2. AMI_Init 3. AMI_GetWave Arpad shared an email from Ambrish, which voted for item number 1. Arpad suggested we could eliminate item number 3, since Cadence had asked for this. Walter agreed with this. Arpad narrowed the list to options 1 and 2. Walter noted he strongly recommends AMI_Impluse, since AMI_Init will require a lot of work to change the IBIS specification. Randy asked about the difference between the two approaches and how the memory is handled. Walter responded, if you use AMI_Impulse, all the Tx has to do is write a BCI out string, which gets passed to the Rx model. The model only has to parse this BCI string. If we use the AMI_Init, we have to change how the branch is output. And, the Rx model will have to parse the entire AMI parameters. In terms of simulation efficiency, there would not be much difference between AMI_Impluse and AMI_Init. Walter made a motion to vote on the options for enabling Back Channel Interface in statistical. Randy seconded the motion. There were no objections. The roll call vote tally was: Cadence - Option 1. Mentor - Option 1. Micron - Option 1. SiSoft - Option 1. SPISim - Option 1. Teraspeed Labs - Option 1. The roll call vote concluded with a vote tally of Option 1. – 6, Option 2. – 0, Abstain – 0. Option 1. was selected as the path forward. Walter took an AR to draft a BIRD on based on the AMI_Impulse approach for this group to review. BIRD197.6_draft3: Arpad asked Bob to review the changes to BIRD197.6_draft3. Bob had made changes to reflect the discussion from the last meeting. Arpad asked about the sentence Michael had added, but he had later requested to be removed. Bob stated he had not captured this change. Arpad noted the latest email from Michael stated he wanted to withdraw his requested additional text. Bob stated it is unclear which text this applies to. Walter noted at the beginning of the email the text was requested, so the comment to withdraw the sentence was in this context. Walter suggested to delete the sentence: "This shall include, but is not limited to, channel effects as well as the impact of any equalization imposed by the transmitter." from the BIRD draft. Bob removed this sentence and saved the document as draft4 of BIRD197.6. Arpad asked if there was any further discussion on BIDR197.6. Walter suggested to post this and plan to review and vote to submit the BIRD to the IBIS Open Forum. Bob suggested to vote on it today. Walter moved to submit BIRD197.6 to the IBIS Open Forum. Randy seconded the motion. There were no objections. Bob took an AR to submit BIRD197.6 to the IBIS Open Forum. Arpad suggested to change the red text to black text. Mike suggested the revision markup should show the difference from the previous version (BIDR197.5), but Randy could do this if he chooses. BIRD181.2: Mike suggested to give a brief review of the BIRD. BIRD181.2 is on the topic of IV curve clarifications. Mike noted BIRD181.2 is a draft, where he started with IBIS 7.0 as the basis. He mentioned changes of "pin" to "terminal" and other consistency changes. The BIRD now covers three sections. The first change uses a spice like notation to express the names of the terminals that the voltage is measured across for [Pulldown], [Pullup], [GND Clamp], and [POWER Clamp]. Arpad asked if there were technical changes in BIRD181.2. Mike replied this is a clarification BIRD to clean up the language. The second change is to the [ISSO PD] and [ISSO PU] keywords to use the same spice like notation. The third change is to V(g,s) from Vgs, where the 'g' and 's' nodes are previously defined in the IBIS specification. The fourth change is also to V(g,s), but in a different section. Mike noted he may need additional changes from "pin" to "terminal" as Walter had suggested. He will need to take care of making this change. Arpad asked about the terms "pins" vs. "pads" and if we would need some changes for these, but this could be a separate effort. Mike agreed this would be a separate effort in new BIRD. Walter asked if we can submit a version that makes these changes to IBIS 7.0. Mike replied he could use markup on the IBIS 7.0 text with these changes. Arpad agreed this could be useful in this case. Mike took an AR to make the changes as noted to BIRD181.2 and send it out. - Walter: Motion to adjourn. - Randy: Second. - Arpad: Thank you all for joining. AR: Walter to draft a BIRD on based on the AMI_Impulse approach. AR: Bob to submit BIRD197.6 to the IBIS Open Forum. AR: Mike to make the changes as noted to BIRD181.2 and send it out. ------------- Next meeting: 10 December 2019 12:00pm PT ------------- IBIS Interconnect SPICE Wish List: 1) Simulator directives