================================================================================ IBIS INTERCONNECT TASK GROUP Mailing list: ibis-interconnect@freelists.org ================================================================================ Attendees from March 29, 2023 Meeting (* means attended at least using audio) ANSYS Curtis Clark Intel Corp. Michael Mirmak* Michael Brownell Keysight Technologies Ming Yan Marvell Steve Parker MathWorks Walter Katz* Micron Technology Justin Butterfield* Randy Wolff* Siemens EDA Arpad Muranyi* ST Microelectronics Aurora Sanna Teraspeed Labs Bob Ross* University of Illinois Jose Schutt-Aine Zuken USA Lance Wang* ---------------------------------------------------------------- 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 March 22, 2023 meeting. Michael displayed the minutes. Arpad Muranyi moved to approve the minutes. Bob Ross seconded. The minutes were approved without objection. Review of ARs: - Michael to check if the Network Analyzer manuals documenting the original Touchstone can be posted to the IBIS website [AR]. - Michael noted that Keysight's legal department had contacted him with questions, which he answered. He suggested keeping this open until there are further updates. - Michael to find out if Synopsys HSPICE supports arbitrary ordering of options line elements [AR]. - Michael suggested to keep this open. - Arpad to write a TSIRD5 to add multiple reference impedances in Touchstone 2.1. - Arpad reported that this is done. Opens: - Michael to look into a transcription option for detailed minutes [AR]. Randy Wolff noted the issue with transcription is that it needs to be enabled in the meeting, and it needs to be enabled by the owner of the meeting which is usually SAE. Michael suggested to discuss the details offline. - Bob requested to give a presentation which compares Touchstone 1 and Touchstone 2 as a refresher of an old DesignCon presentation from 2008. Michael agreed we can add this on the agenda. - Bob would like to see the HSPICE documentation on the Touchstone per port reference impedance syntax. He would also like to have a Synopsys representative in this meeting to discuss the details of the proposed syntax. Michael noted the timezones are not friendly for Ted Mido to attend. Arpad asked if Bob has sent an email with his questions. Michael asked if there is a version of the HSPICE documentation Bob would like to see. He noted that publicly available copies of the HSPICE manual would be better to discuss. Bob replied that the Touchstone syntax documentation is the area of interest. Bob asked if Synopsys would have an example Touchstone file. Discussion: TSIRD5 draft1: Arpad shared the TSIRD5 draft that he created. He wanted to make sure that the per port reference impedance on the Option line should be the only main change in a proposed Touchstone 2.1. Arpad reviewed the changes proposed by the TSIRD. Bob stated that we have an existing rule on the order of the Option line. Walter Katz noted that he requires that we follow the HSPICE format without deviation. Arpad agreed that this is his goal as well. He suggested that we need clarification from Synopsys before resolving this. Arpad noted there are three examples in the specification with a statement that the data cannot be represented using Touchstone 1.0 syntax which would probably need to be removed. Randy asked about the rules for version 1 and rules for version 2. Arpad wanted to make sure the discussion included the case where both the Reference impedance and Option line are specified. He wanted to cover all the possible combinations of duplication in the specification. Arpad noted a typo on page 7 of the Touchstone 2 specification. Bob stated we could have many reference impedances, and this could make the Option line long. Arpad thought we do not have a line length limitation in Touchstone 2, but he was not sure about HSPICE. Michael agreed this could be an issue. Bob was concerned by the Version keyword not being present. Michael commented, to make this work, we have to make all the keywords, including Version, optional. If you have any other bracketed keywords, then the Version keyword is required. Bob stated there is a misconception that the file becomes a Touchstone 1 file. He thought we could call this something else, because we don't have a way to differentiation from Touchstone 1.0 to 2.1. Arpad noted, if you have multiple entries on the Option line, you will know that it is a different version. Bob was concerned with the naming of the specification with this rule. Arpad stated, if we want to call it Touchstone 1.1, then we would need to complete the separation work. He did not see the value in doing this. Bob was concerned about the normalization of the data with the reference impedance. Walter suggested we need to clarify this with Synopsys and what is expected for the per port reference impedance. Arpad suggested to draft an email to Ted with these questions. Bob will email Ted with his questions [AR]. Arpad moved to adjourn. Bob seconded. The meeting adjourned. Next Meeting: The next meeting will be April 5, 2023. ================================================================================ Bin List: 1. Draft Touchstone document separating version 1.0 and 2.0 2. Encapsulating Touchstone 1.0 data 3. Touchstone 2.0 draft with TSIRD3 and TSIRD4 4. Pole-residue format 5. Port naming 6. Alternatives to the Touchstone 1.0 option line 7. Enable Cascading of S-parameters Through W-element 8. Touchstone 3.0 draft outline (dependent on several items above) Tabled ARs: - Arpad to give an example of the physical connectivity needed for EMD automation.