================================================================================ IBIS INTERCONNECT TASK GROUP http://www.ibis.org/interconnect_wip/ Mailing list: ibis-interconnect@freelists.org Archives at http://www.freelists.org/archive/ibis-interconn/ ================================================================================ Attendees from December 20 Meeting (* means attended at least using audio) ANSYS Curtis Clark* Cadence Design Systems Bradley Brim Cisco David Siadat Intel Corp. Michael Mirmak* Keysight Technologies Radek Biernacki, Ming Yan Mentor, A Siemens Business Arpad Muranyi* Micron Technology Justin Butterfield*, Randy Wolff* SAE ITC Maureen Lemankiewicz, Logen Johnson Signal Integrity Software Walter Katz*, Mike LaBonte* Teraspeed Labs Bob Ross* University of Aveiro in Portugal Wael Dghais Michael Mirmak convened the meeting. No patents were declared. Justin Butterfield took minutes. Review of Minutes: - Michael called for review of the minutes from the December 13 meeting. Mike LaBonte moved to approve the minutes. Randy Wolff seconded. The minutes were approved without objection. Review of ARs: - None Opens: - Bob Ross stated that he would like to go over Randy's presentation on how Micron might intend to model a real package example using BIRD189. Michael asked if this discussion would include Aggressors. Randy commented that he has an example with both high speed and low speed signals. Bob has some questions on it. Summary From ATM: Michael noted that the ATM group went over Mike's diagram on Aggressors. Mike commented that he has posted the slide. He has some ideas on how to improve it, but has not had time to finish that yet. Bob would like to see the improvements. Package Model Example: Randy showed an example of a Graphics DRAM with a BGA package. It has a high speed DQ data bus, a lower speed Address/Command bus, and a very low speed JTAG bus. The slide gives some options of differing package models Randy might create for this example. He noted that the package is too large to create a single S-parameter model for all the nets. Randy envisioned having an S-parameter model for a quadrant of the package with the DQ bus. For the Lower speed Address/Command, he would have a fully-coupled spice model. And, the JTAG bus would have RLC values only. Randy commented he sees using the Aggressor designator for pre-layout type models where not all the coupling is included. Walter Katz asked if the quadrants of DQs would be routed the same and could use the same S-parameter model. Randy stated that they may be the same in some cases and not in others. Walter asked about the Address/Command signals and if they would be in the same Set. Randy replied that could work. Walter asked when Randy would use the Aggressor designator. He noted that RAS_n could be added as an Aggressor on the DQ model in Randy's example. Walter asked if the current proposal would work for the models that Randy would want. Randy stated he thought it would work to support his needs. Bob asked what device the example is for. Randy replied that it is a GDDR5. Bob asked if there are any other packages for this same device. Randy stated that this is the only package. Bob asked if Randy would create one S-parameter model for the DQ block and if he would collapse the power and ground rails. Randy replied he would likely collapse the power rail to a single port on each end. He would have an s24p model for signals only or an s26p model including the VDDQ rail. Bob asked what the different colors mean and if these would be in different Groups. Randy noted that his customers might simulate a byte lane with or without coupling terms. The darker blue is the Address/Command and would likely be simulated separately from the DQ data bus. Randy commented that this approach is analogous to cropping the package to only certain nets. Michael asked if we cannot assume that the drawing relates to the actual EM coupling. Walter noted that it could be the case that signals in different signal groups are partitioned with very little coupling between them. He noted that the package vendor will have this information and know how to partition the models. Walter asked Randy if he would also provide uncoupled models. Bob noted you could use the legacy package model in this case. Randy replied he may want more accurate models than the legacy package models for the uncoupled cases. Bob asked if Randy's example would have full path S-parameter models. Randy noted in this particular case, the buffer and pad are at the same physical location. Bob asked if this is true for power and ground as well. Randy replied that is a decision he would need to make of whether to include the on-die PDN and in how much detail. Bob asked how he would include the power terminal connections. Randy replied he would have to think about it. Aggressor Treatment: Walter stated that he would like to decide whether to include his changes to the Aggressor treatment. Michael asked if there are any technical objections to the document that includes these changes. Bob said he does not any have objections, but he has some questions. He also thought the document is confusing, and the text needs some revisions. Walter moved to post the BIRD189.5_draft13.1 he sent out as the official BIRD189.5_draft14. Bob seconded. There were no objections. Mike to post draft13.1 as draft14 [AR]. Bob commented that there is substantial editorial work to do. He noted there are numerous forward references in the BIRD. Michael asked Bob to start working on the editorial changes to the BIRD [AR]. Bob said he can work on it, but he has some additional text he would like to add. Bob asked about the term "pad" vs. "die pad" and what should be used in the document. Walter suggested for Bob to make things as consistent as possible. Upcoming Meeting Schedule: Michael asked about the upcoming meeting schedule. There was general agreement to hold the next meeting on January 3, 2018. Mike stated he can chair the meeting, and Randy volunteered to take the minutes. Bin List Discussion: Bob noted that we can remove the File_TS0 item from the bin list. Mike noted there are comments to be resolved in the document including Radek's suggestion to change “may†to "shall†on page 26. Mike noted he will withdraw his suggestion to remove the phrase "by the EDA tool". Arpad stated that he would like to have an example that shows the use of the A_gnd syntax. Walter noted that we still need to fix the Requirements at the beginning of the BIRD. Mike moved to adjourn. Randy seconded. The meeting adjourned without objection. Task List BIRD189.5 editorial additions/changes to be completed: 1. Remove the word "reference" from the IBIS-ISS examples 2. Clarify the terms "Model", "Sets" and "Groups" 3. Resolve the comments in the document (e.g., on page 26, addressing “may†vs. “should/shallâ€) 4. Remove comments from Mike LaBonte regarding use of the phrase "by the EDA tool" 5. Add a new example showing the A_gnd syntax 6. Remove or modify Requirements 12 and 15