Minutes from the January 19, 2022 IBIS Interconnect Task Group meeting are
attached.
Regards,
Justin
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IBIS INTERCONNECT TASK GROUP
http://www.ibis.org/interconnect_wip/ ;
Mailing list: ibis-interconnect@xxxxxxxxxxxxx
Archives at //www.freelists.org/archive/ibis-interconn/ ;
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Attendees from January 19, 2022 Meeting (* means attended at least using audio)
ANSYS Curtis Clark
Intel Corp. Michael Mirmak*
MathWorks Walter Katz*
Micron Technology Justin Butterfield*
Randy Wolff*
Siemens EDA Arpad Muranyi*
ST Microelectronics Aurora Sanna*
Teraspeed Labs Bob Ross*
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 January 12, 2022 meeting.
Michael displayed the minutes. Lance Wang moved to approve the minutes.
Randy Wolff seconded. The minutes were approved without objection.
Review of ARs:
- None.
Opens:
- Arpad Muranyi suggested to discuss the Designator Pin Relaxation BIRD draft
first before the other agenda items.
Designator Pin Relaxation:
Arpad reviewed draft 4 that was sent out with cyan colored changes based on
feedback from Curtis Clark. The draft does not include the "NC" change
proposal yet. Randy asked if we are considering using "NA" as the
signal_type. Arpad replied we would have to establish a special meaning for
"NA". Bob Ross commented this would be a new application of using "NA".
Arpad commented it would be nice to not require all the pins to be listed, but
should we not allow pins which are not connected to be listed. Michael asked
if there were any complaints or feedback on this. Arpad stated the issue is
with the efficiency of the EMD files. Bob commented we need to be careful
with the rules, as there are many interactions to consider. Arpad noted one
issue is that "NC" is not properly defined. Bob agreed there are multiple
meanings of "NC" pins. Randy commented "NC" is a flag to the EDA tool to not
simulate the pin. Arpad noted he needs more feedback to make decisions on the
direction of this BIRD draft.
Touchstone 3:
Walter Katz stated there are many users which have software to read in
Touchstone files, and many have not updated their software to support
Touchstone 2. He suggested to support backward compatibility. He suggested
to support machine readable port definitions and sparse matrix format in
Touchstone 3.
Bob commented our goal for Touchstone was to create an official
specification. The objective for Touchstone 2 was not to have backwards
compatibility with Touchstone 1. Walter suggested to keep Touchstone 2 and
Touchstone 3 backward compatibility but not for Touchstone 1.
Walter commented that it seems everyone is okay to go with Touchstone 2 as the
starting point. He asked if there are any issues or clarifications for
Touchstone 2. Randy suggested to spend some time looking at the survey data.
Arpad stated file size is one issue. Bob suggested to drop the Binary Format
support changes. Arpad noted the binary format helps to remove the file size
dependency on the data precision. Walter commented the half-matrix format
reduces the file size by a factor of two, and the binary format can reduce the
file size by another factor of two.
Michael asked if there are any other approaches to compress the files. Arpad
suggested the pole-zero format would be a way to significantly reduce the file
size. Walter agreed a standard way to represent an S-parameter as a
subcircuit would be useful, but we can use IBIS-ISS for that. Michael noted
one side effect of the pole-zero format is there is not an easy way to
graphically view the data, such as insertion loss and return loss plots.
Arpad asked how much people would trust the pole-zero format. Randy stated
the pole-zero format will force the data to be causal, and some tools do a
similar conversion already. Walter suggested we would have to come up with a
new name and not have it as part of Touchstone. Aurora Sanna stated the
pole-zero format looks like a good option for making models faster, but we
would need to support both model types. Arpad noted they convert the
Touchstone models to pole-zero and that step takes significant time.
Randy asked if there is a way to reduce ports in the pole-zero format. Arpad
will ask Vladimir if it is possible to reduce ports in the pole-zero format
[AR].
Michael asked everyone to provide their requirements for the pole-zero format
[AR].
Next Meeting:
The next meeting will be January 26.
Arpad moved to adjourn. Randy seconded. The meeting adjourned without
objection.
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Bin List:
1. Touchstone 3
2. Pole-zero support for Touchstone
3. New version of Touchstone to include 3 TSIRDs
4. Clarification BIRD drafts from ATM
