Radek,
Regarding "...to ignore not only the analog buffer description under the
[Model] keyword but also any package information...",
I don't think that the intent of BIRD158 was to include the package parasitics
in its Ts4file and therefore ignore
the existing package related keywords and data in the .ibs file. My
understanding is that this proposal ONLY
intends to replace the I-V / V-t curve and C_comp based [Model] (or [External
Model] and nothing else.
Thanks,
Arpad
=====================================================================================
From: ibis-macro-bounce@xxxxxxxxxxxxx [mailto:ibis-macro-bounce@xxxxxxxxxxxxx] ;
On Behalf Of BIERNACKI,RADEK (K-Sonoma,ex1)
Sent: Tuesday, May 16, 2017 1:34 PM
To: bob@xxxxxxxxxxxxxxxxx; 'IBIS-ATM' <ibis-macro@xxxxxxxxxxxxx>
Subject: [ibis-macro] Re: Quick questions on BIRD158.5
Hi All,
Indeed, very good discussion. All points made by Bob are important and need to
be addressed in 158.6.
Regarding one of Michael's original question and Walter's reply:
"Note that when the reserved parameter Ts4file is defined in the AMI model the
Tx or the Rx schematic shown above is to be used in lieu of the analog buffer
model and the package defined in the .ibs file. "
Should be
"Note that when the reserved parameter Ts4file is defined in the AMI model the
Tx or the Rx schematic shown above is to be used in lieu of the analog buffer
model defined in the .ibs file. "
Simple removal of the words "and the package" may not carry the intended
notion. We need to be clear that BIRD 158.x intent was to ignore not only the
analog buffer description under the [Model] keyword but also any package
information whether provided by the original [Package] keyword or the [Package
Model] keyword. In other words the use of the package info from the IBIS file
was not to be mandated. That would naturally extend to the same treatment of
the new package modeling proposed in BIRD 189.x. From that point of view it was
left to the user to include any package data within the "User Setup" shown in
the diagram. Any wording improvement to make it clearer is welcome.
Radek
From: ibis-macro-bounce@xxxxxxxxxxxxx<mailto:ibis-macro-bounce@xxxxxxxxxxxxx>
[mailto:ibis-macro-bounce@xxxxxxxxxxxxx] On Behalf Of Bob Ross
Sent: Friday, May 12, 2017 10:44 AM
To: 'IBIS-ATM' <ibis-macro@xxxxxxxxxxxxx<mailto:ibis-macro@xxxxxxxxxxxxx>>
Subject: [ibis-macro] Re: Quick questions on BIRD158.5
All,
Good discussion and more comments or responses for the ATM meeting and pending
BIRD158.6:
1. I would state that a new subsection is proposed: 10.X be added for
IBIS-AMI Analog Buffer Model Parameters
2. The changes should start with an INTRODUCTION to define a term: "This
section discusses connections to 4-port analog circuit data file models
described in a Touchstone format and named by a Ts4file parameter." (note,
Ts4file implies a restrictedTouchstone format, but this is never defined until
later. We could read the text to include four-port data in ibis-iss, vhdl,
etc. formats.)
3. Subsection Title TRANSMITTER DRIVER ANALOG CIRCUIT --> DRIVER ANALOG
CIRCUIT or --> TRANSMITTER ANALOG CIRCUIT
4. In the paragraph beginning with The IBIS AMI flow: specified according
to this BIRD --> specified here
5. Subsection Title RECEIVER ANALOG TERMINATION CIRCUIT --> RECEIVER
ANALOG CIRCUIT
6. Also, we might need to wait for BIRD186.x regarding terminology and
the added limitations that the quoted file names can include directory paths
per revised naming rules in section 3. (e.g., "../spar/s4p.sp" would be illegal)
7. As in other sections, two Tables should be added for the five new
parameters:
a. General Rules and Allowable Usage for Analogy Circuit Reserved
Parameters
b. Allowable Data Types for Supporting Analog Circuit Reserved Parameters
Also, it is stated that these parameters do not interact with the Interconnect
Model parameters (in BIRD189.X)
Bob
From: ibis-macro-bounce@xxxxxxxxxxxxx<mailto:ibis-macro-bounce@xxxxxxxxxxxxx>
[mailto:ibis-macro-bounce@xxxxxxxxxxxxx] On Behalf Of Muranyi, Arpad
Sent: Thursday, May 11, 2017 7:14 PM
To: wkatz@xxxxxxxxxx<mailto:wkatz@xxxxxxxxxx>;
michael.mirmak@xxxxxxxxx<mailto:michael.mirmak@xxxxxxxxx>; IBIS-ATM
Subject: [ibis-macro] Re: Quick questions on BIRD158.5
Mike,
I agree with Walter's answers. I would only add that I think we should also
change the terminology
and refrain from using "Analog Termination Circuit", because these Touchstone
models are really
"buffer models", not "terminator models". Our IBIS vocabulary does make a
difference between
buffers and terminators, and using the word termination in this context is
inconsistent and
confusing with that. (I actually had a rather bloody argument about this with
someone, who was
under the impression that these Touchstone models were not buffer models).
Thanks,
Arpad
=============================================================================
From: ibis-macro-bounce@xxxxxxxxxxxxx<mailto:ibis-macro-bounce@xxxxxxxxxxxxx>
[mailto:ibis-macro-bounce@xxxxxxxxxxxxx] On Behalf Of Walter Katz
Sent: Thursday, May 11, 2017 8:35 PM
To: michael.mirmak@xxxxxxxxx<mailto:michael.mirmak@xxxxxxxxx>; IBIS-ATM
<ibis-macro@xxxxxxxxxxxxx<mailto:ibis-macro@xxxxxxxxxxxxx>>
Subject: [ibis-macro] Re: Quick questions on BIRD158.5
MM,
"Note that when the reserved parameter Ts4file is defined in the AMI model the
Tx or the Rx schematic shown above is to be used in lieu of the analog buffer
model and the package defined in the .ibs file. "
Should be
"Note that when the reserved parameter Ts4file is defined in the AMI model the
Tx or the Rx schematic shown above is to be used in lieu of the analog buffer
model defined in the .ibs file. "
This was decided and agreed to. I think it was an error that "and the package"
was not removed.
Th paragraph before this explictily excludes the package model (and note the
typolographical and spelling errors in red):
The IBIS AMI flow requires that the EDA tool generates the impulse response of
the the entire analog circuitry from Tx to Rx algotithmic models. Typically,
the Touchstone file data specified according to this BIRD is to be used for
either the Tx analog buffer excluding the Tx package model and/or the Rx analog
buffer model excluding the Rx package model. The following figure illustrates
the entire setup when both Tx and Rx use the Ts4file parameter.
There are errors in the following paragraph which describes methods to generate
the impulse response:
Given that the Touchstone 4-port model is LTI there are many methods of
generating the impulse response to be used in AMI modeling that will give the
identical result within numerical accuracy of the technique chosen. One
technique commonly used in EDA tool simulation is to generate the step response
by applying a step stimulus and calculating the time derivative of that step
response. When both Tx and Rx Ts4file parameters are present the step response
is measured between the SRC_pos/SRC_neg input and a high impedance differential
probe between Ports 2 and 4 of the Rx 4-port network. When only one of Tx or Rx
.ami files has the Ts4file parameter present then the other component's
contribution to the step response (or just the impulse response) comes from the
model details provided under the [Model] keyword referencing the .ami file
without the Ts4file parameter.
Should be:
Given that the Touchstone 4-port model is LTI there are many methods of
generating the impulse response to be used in AMI modeling that will give the
identical result within numerical accuracy of the technique chosen. One
technique commonly used in EDA tool simulation is to generate the impulse
response by applying a step stimulus and calculating the time derivative of
that step response. When both Tx and Rx Ts4file parameters are present the
impulse response is measured between the SRC_pos/SRC_neg input and a high
impedance differential probe between Ports 2 and 4 of the Rx 4-port network.
When only one of Tx or Rx .ami files has the Ts4file parameter present then the
other component's contribution to the impulse response comes from the model
details provided under the [Model] keyword referencing the .ami file without
the Ts4file parameter.
Walter
Walter Katz
wkatz@xxxxxxxxxx<mailto:wkatz@xxxxxxxxxx>
Phone 303.449-2308
Mobile 303.335-6156
From: ibis-macro-bounce@xxxxxxxxxxxxx<mailto:ibis-macro-bounce@xxxxxxxxxxxxx>
[mailto:ibis-macro-bounce@xxxxxxxxxxxxx] On Behalf Of Mirmak, Michael
Sent: Thursday, May 11, 2017 9:18 PM
To: IBIS-ATM (ibis-macro@xxxxxxxxxxxxx<mailto:ibis-macro@xxxxxxxxxxxxx>)
<ibis-macro@xxxxxxxxxxxxx<mailto:ibis-macro@xxxxxxxxxxxxx>>
Subject: [ibis-macro] Quick questions on BIRD158.5
Sorry for last-minute questions on BIRD158, but I wanted to ensure these could
be addressed during the technical discussion in the Open Forum:
1) The TX and RX "Analog Termination Circuit" sections - it's not
immediately clear where in the specification these are supposed to go. It
would help to note the section in which these are to be inserted.
2) In the text, the following phrase is used:
"Note that when the reserved parameter Ts4file is defined in the AMI model the
Tx or the Rx schematic shown above is to be used in lieu of the analog buffer
model and the package defined in the .ibs file. "
Will the phrase "and the package" regarding package models be revised or
removed once BIRD189.x is approved?
3) Related to this, the entire sentence should appear *before* the link
setup circuit diagram that immediately precedes it, to prevent reader confusion.
4) Also related to this, the link setup diagram should be altered to make
the package portion of the "User Setup" block optional. Otherwise, the diagram
conflicts with the statement regarding the replacement of the package
information in the .ibs file.
5) The last paragraph of the BIRD text to be added to IBIS mentions step
responses vs. impulse responses. As the phrase "step response" is never used
in IBIS 6.1, and the information supplied applies just as much to impulse
responses, is the entirety of this paragraph needed?
Thank you!
- MM