Ken,
We are already talking about using the on-die S-parameter data as part of
theanalog model - in fact, we're talking about using S-parameter data as
pretty much the entire analog model, as shown in slide 10 of the
presentationArpad referenced.

I think confusion may come from conversations in the IBIS-ATM working group,
where we've been talking about referencing on-die S-param data (used for the
analog model) from the .ami file instead of the .ibs file.

Walter is welcome to comment on the reasons for this, but I'll share my view
- this is a purely pragmatic decision, designed to move SerDes modeling
forward as fast as possible. We proposed syntax for including on-die
S-params in the .ibs file at the Feb 2009 IBIS Summit, and the working group
soon realized there were issues for single-ended, non-SerDes I/O that needed
significant discussion. We've been looking for a way to limit scope and
moveforward faster - using the .ami file is one way to clearly indicate this
is targeted for SerDes use and not intended as part of a broader, more
general purpose solution.

Todd.
Todd Westerhoff VP, Software Products SiSoft 6 Clock Tower Place, Suite 250
Maynard, MA 01754 (978) 461-0449 x24 twesterh (AT) sisoft (DOT) com[1]
www.sisoft.com[2]

Ken Willis wrote: Hi Todd, On #1, it makes sense to incorporate S-parameters
into IO models, especially since some major IP suppliers have this data
today. I think the item that brings some uncertainty is why this would be
pushed into the algorithmic (AMI) portion of the model, especially if new
syntax/API has to be invented and supported. The intent of AMI was to
capturethe adaptive filtering behavior of these advanced Serdes devices,
which you couldn't really model well in a circuit model. If the S-parameters
are largely parasitic data, it seems more straightforward to include them in
the analog circuit part of the model. I understand that there is no standard
"IBIS" syntax for S-params right now, but I would agree with Arpad that
Touchstone is widely supported. Maybe we should be looking at [External
Model] >Touchstone or something like that. But we can continue the
discussionin the IBIS forum. Thanks, Ken Willis Sigrity, Inc. 860-871-7070
kwillis (AT) sigrity (DOT) com[3] -----Original Message----- From:
si-list-bounce (AT) freelists (DOT) org[4] [mailto:si-list-bounce (AT) freelists (DOT) org[5]] On
Behalf Of Todd Westerhoff Sent: Tuesday, February 09, 2010 9:29 AM To:
Muranyi, Arpad Cc: si-list (AT) freelists (DOT) org[6] Subject: [SI-LIST] Re: IBIS-AMI
Vendor Support Help Arpad, Two points worthy of note: 1) I think there's a
balance between adapting models to fit the current standard and extending
thestandard to improve the way we utilize vendor data. One of the goals we
had for IBIS-AMI was to utilize model data vendors already have, S-parameter
characterizations of on-die behavior being the obvious case. This should
legitimately be considered part of the device model and IBIS-AMI should
accommodate it as such. Telling people to include on-die S-parameters as
partof the channel may comply with the current spec, but I don't think
that'sthe way semiconductor vendors or users want to manage that data ... it
just creates more opportunity for error. 2) A clear and unambiguous
definition of on-die S-parameter syntax was presented at the Feb 2009 IBIS
Summit, for exactly the reasons you mentioned. Thanks, Todd. Todd Westerhoff
VP, Software Products SiSoft 6 Clock Tower Place, Suite 250 Maynard, MA
01754(978) 461-0449 x24 twesterh (AT) sisoft (DOT) com[7] www.sisoft.com[8] Muranyi,
Arpad wrote: Sanjeev, I would recommend the following: Zero out the package
related stuff in the .ibs file to basically turn package modeling off in it.
Provide an S-parameter package file separately the same way as the channel's
S-parameter file would be distributed. This could be documented in the .ibs
file behind comments. The customer will use whatever method to include this
in their favorite EDA tool. If there is a need for on-die interconnect
parasitic modeling, it could be done the same way as the package model
described in the previous paragraph. The two might even be combined into a
single S-parameter file if that is more convenient or practical. I would NOT
provide a speculated IBIS syntax or any tool specific syntax in the .ibs
filefor anything, unless a clear and unambiguous description is given, so
that another EDA vendor could reproduce the same results with their
products.For the rest of the buffer description I would encourage everyone
touse existing IBIS constructs as far as possible. And again, if certain
features cannot be described that way, I would encourage everyone to provide
a detailed description for what needs to be modeled so that anyone could
maketheir own model implementations using their favorite EDA tools based on
that description. Thanks for asking the question. Arpad
================================================== ==============
-----Original Message----- From: sanjeev_gupta (AT) agilent (DOT) com[9]
[mailto:sanjeev_gupta (AT) agilent (DOT) com[10]] Sent: Monday, February 08, 2010 5:29
PM To: Muranyi, Arpad; si-list (AT) freelists (DOT) org[11] Cc:
sanjeev_gupta (AT) agilent (DOT) com[12] Subject: RE: [SI-LIST] Re: IBIS-AMI Vendor
Support Help Hello Arpad, What will be your advice to companies who are
ramping up on AMI? Should they include some non-AMI syntax for package
modeling assuming that IBIS AMI standard will support these keywords in near
future or provide these package model as a separate Touchstone file which
canbe integrated within simulation environment? Best regards Sanjeev
------------------------------------------------------------------ To
unsubscribe from si-list: si-list-request (AT) freelists (DOT) org[13] with
'unsubscribe' in the Subject field or to administer your membership from a
web page, go to: http://www.freelists.org/webpage/si-list[14] For help:
si-list-request (AT) freelists (DOT) org[15] with 'help' in the Subject field List
technical documents are available at: http://www.si-list.net[16] List
archives are viewable at: http://www.freelists.org/archives/si-list[17] Old
(prior to June 6, 2001) list archives are viewable at:
http://www.qsl.net/wb6tpu[18]
------------------------------------------------------------------ To
unsubscribe from si-list: si-list-request (AT) freelists (DOT) org[19] with
'unsubscribe' in the Subject field or to administer your membership from a
web page, go to: http://www.freelists.org/webpage/si-list[20] For help:
si-list-request (AT) freelists (DOT) org[21] with 'help' in the Subject field List
technical documents are available at: http://www.si-list.net[22] List
archives are viewable at: http://www.freelists.org/archives/si-list[23] Old
(prior to June 6, 2001) list archives are viewable at:
http://www.qsl.net/wb6tpu[24]

--- Links ---
1 mailto:twesterh (AT) sisoft (DOT) com
2 http://www.sisoft.com
3 mailto:kwillis (AT) sigrity (DOT) com
4 mailto:si-list-bounce (AT) freelists (DOT) org
5 mailto:si-list-bounce (AT) freelists (DOT) org
6 mailto:si-list (AT) freelists (DOT) org
7 mailto:twesterh (AT) sisoft (DOT) com
8 http://www.sisoft.com
9 mailto:sanjeev_gupta (AT) agilent (DOT) com
10 mailto:sanjeev_gupta (AT) agilent (DOT) com
11 mailto:si-list (AT) freelists (DOT) org
12 mailto:sanjeev_gupta (AT) agilent (DOT) com
13 mailto:si-list-request (AT) freelists (DOT) org
14 http://www.freelists.org/webpage/si-list
15 mailto:si-list-request (AT) freelists (DOT) org
16 http://www.si-list.net
17 http://www.freelists.org/archives/si-list
18 http://www.qsl.net/wb6tpu
19 mailto:si-list-request (AT) freelists (DOT) org
20 http://www.freelists.org/webpage/si-list
21 mailto:si-list-request (AT) freelists (DOT) org
22 http://www.si-list.net
23 http://www.freelists.org/archives/si-list
24 http://www.qsl.net/wb6tpu
------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request (AT) freelists (DOT) org with 'unsubscribe' in the Subject field

or to administer your membership from a web page, go to:
http://www.freelists.org/webpage/si-list

For help:
si-list-request (AT) freelists (DOT) org with 'help' in the Subject field


List technical documents are available at:
http://www.si-list.net

List archives are viewable at:
http://www.freelists.org/archives/si-list

Old (prior to June 6, 2001) list archives are viewable at:
http://www.qsl.net/wb6tpu