Minutes from the 10 January 2017 ibis-atm meeting are attached.
Mike
IBIS Macromodel Task Group
Meeting date: 10 January 2017
Members (asterisk for those attending):
ANSYS: * Dan Dvorscak
Curtis Clark
Broadcom (Avago): Xingdong Dai
* Bob Miller
Cadence Design Systems: * Ambrish Varma
Brad Brim
Kumar Keshavan
Ken Willis
Cisco: Seungyong (Brian) Baek
eASIC: David Banas
Marc Kowalski
Ericsson: Anders Ekholm
GlobalFoundries: * Steve Parker
IBM Luis Armenta
Trevor Timpane
Intel: * Michael Mirmak
Keysight Technologies: Fangyi Rao
* Radek Biernacki
Ming Yan
Maxim Integrated Products: Hassan Rafat
Mentor Graphics: John Angulo
* Arpad Muranyi
Micron Technology: * Randy Wolff
Justin Butterfield
QLogic Corp.: James Zhou
Andy Joy
SiSoft: * Walter Katz
Todd Westerhoff
* Mike LaBonte
Synopsys: Rita Horner
* Kevin Li
Teraspeed Consulting Group: Scott McMorrow
Teraspeed Labs: * Bob Ross
TI: Alfred Chong
The meeting was led by Arpad Muranyi.
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Opens:
- Arpad: Mike LaBonte is taking minutes.
- Arpad: We will cancel the Jan 31 meeting which conflicts with DesignCon.
We will meet Jan 17 and 24.
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Review of ARs:
- AR: Walter to email his example and BIRD 158.4 to the ATM list.
- Done
- AR: Mike LaBonte to update the "IBIS 6.2 BIRD Candidates" to rev 7 and send it
to the ATM list.
- Done
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Call for patent disclosure:
- None.
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Review of Previous Meeting Minutes:
- Arpad: Does anyone have any comments or corrections? [none]
- Michael M.: Motion to approve the minutes.
- Bob Ross: Second.
- Arpad: Anyone opposed? [none]
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New Discussion:
BIRD147.5:
- Arpad noted that BIRD 147.5 had been recently emailed, and that it had been
scheduled for
a vote in the previous Open Forum meeting, but that had been deferred. Bob
Miller showed
the BIRD. He said there were issues with BCI_GetWave_Block_UI related to
rounding. It
needed to be an integer and BIRD 147.5 has been tweaked for that. The
parameter name was
now BCI_Message_Interval_UI and the definition had been changed. It informs
the EDA tool
what the interval wants to be. It is wide open as to what the optimization
should be. Bob
Ross said the Type should be Integer. Bob Miller changed Type to Integer. -
Bob Miller
proposed that models should be forgiving if AMI block size does not exactly
match the
requested frequency, and that BCI_Training_UI should be extended by tools to
synchronize
with the message interval. The expected number of adaptation steps should be
achieved.
Radek Biernacki said the definition probably should be more precise. When
training time ends
one more GetWave should be called before actually ending training. Ambrish
Varma said that
that was in the notes section. Radek said we would need to be careful about
interactions
with BCI_State. Bob Miller believed there would not be any interactions with
that. Ambrish
said if the model does not end training the EDA tool will take over. Bob
Miller said that
to have bit by bit accuracy the model would have to guarantee that it exactly
matches
device behavior on any EDA platform. Mike LaBonte asked if there should be a
rule that
Message_Interval_UI must be less than Training_UI, so ibischk could check it.
Bob Miller
said models would not necessarily message every time they were called, and
that performance
might degrade about 15% if the message window is long. Ambrish Varma
suggested it might be
better to add examples to the specification to illustrate the best practice.
- AR: Bob Miller to update BIRD147.5
BIRD 187.1:
- Michael Mirmak showed the BIRD. He noted that Curtis Clark had suggested
removing "Type
Value" because there is no such thing. The Format for Usage Out is not used
by EDA tools
except for Table. The four rules are all expressed in one paragraph. Michael
said BIRD would
be revised, trying to get down to one simple statement in one location, maybe
two. Radek
Biernacki said the sentence with "except" twice was confusing. It was not
clear how to
display Out data. Bob Ross said we had a list of rules on IBIS 6.1 page 194.
He asked if
the new rules would be moved there. Michael Mirmak said the question was if
the rule should
be stated in each place where it applies, or if it should be stated only
once. Some rules
can be far away in the document. Arpad Muranyi said there could be references
made to a
single location. Mike LaBonte added that including a reference to the
original definition
helps us to know all of the places where a duplicated rule would need to be
changed. Bob
Ross said we might want to explain Usage Out. Michael Mirmak agreed that very
little had
been stated about Usage Out.
AR: Michael Mirmak to send an update to BIRD 187.1.
BIRD158:
- Radek Biernacki said the example needed to be discussed, and that once we
agree, it
should to be ported to the new BIRD template. Bob Ross asked if we really
wanted another
solution, since we already had a solution. He said we had multi-lingual,
asking if we
need a parameter. Ambrish Varma noted the parameter did not have to be in an
AMI file. Bob
Ross said we could link it through IBIS-ISS. Radek said a simpler solution
would be to
just give the Touchstone file name. He said if it remained Model_Specific it
would always
be experimental. Ambrish said that that is provided in the specification if
called from an
[External Model] parameter. Arpad Muranyi said tools wouldn't know what to do
with that. Ambrish
said it should be regarded as an analog model. Walter Katz asked what bad
thing would happen
if it became a Reserved_Parameter. Ambrish said doing so expected the EDA
tool to construct
a canned circuit, and that we already had a right way to do it. Walter said
there is was
right way for frequency domain simulation. Radek agreed there was no right
way, but it was
just an approximation of device behavior. It was "a" way. Arpad asked if
everything was
IBIS file-centric or AMI-centric.
- Arpad: Thank you all for joining.
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Next meeting: 17 January 2017 12:00pm PT
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IBIS Interconnect SPICE Wish List:
1) Simulator directives
