[ibis-macro] Minutes from the 24 Mar 2009 ibis-atm meeting

  • From: "Mike LaBonte (milabont)" <milabont@xxxxxxxxx>
  • To: "IBIS-ATM" <ibis-macro@xxxxxxxxxxxxx>
  • Date: Tue, 31 Mar 2009 14:02:35 -0400

Minutes from the 24 Mar 2009 ibis-atm meeting are attached.

IBIS Macromodel Task Group

Meeting date: 24 March 2009

Members (asterisk for those attending):
  Adge Hawes, IBM
  Ambrish Varma, Cadence Design Systems
  Anders Ekholm, Ericsson
* Arpad Muranyi, Mentor Graphics Corp.
  Barry Katz, SiSoft
* Bob Ross, Teraspeed Consulting Group
  Brad Brim, Sigrity
  Brad Griffin, Cadence Design Systems
  Chris McGrath, Synopsys
  David Banas, Xilinx
  Donald Telian, consultant
  Doug White, Cisco Systems
* Eckhard Lenski, Nokia-Siemens Networks
  Essaid Bensoudane, ST Microelectronics
  Fangyi Rao, Agilent
  Ganesh Narayanaswamy, ST Micro
  Gang Kang, Sigrity
  Hemant Shah, Cadence Design Systems
  Ian Dodd, Agilent
  Jerry Chuang, Xilinx
  Joe Abler, IBM
* John Angulo, Mentor Graphics
  John Shields, Mentor Graphics
  Ken Willis, Cadence Design Systems
  Kumar Keshavan, Sigrity
  Lance Wang, Cadence Design Systems
  Luis Boluna, Cisco Systems
  Michael Mirmak, Intel Corp.
* Mike LaBonte, Cisco Systems
  Mike Steinberger, SiSoft
  Mustansir Fanaswalla, Xilinx
  Patrick O'Halloran, Tiburon Design Automation
  Paul Fernando, NCSU
  Pavani Jella, TI
* Radek Biernacki, Agilent (EESof)
* Randy Wolff, Micron Technology
  Ray Comeau, Cadence Design Systems
  Richard Mellitz, Intel
  Richard Ward, Texas Instruments
  Sam Chitwood, Sigrity
  Sanjeev Gupta, Agilent
  Shangli Wu, Cadence Design Systems
  Sid Singh, Extreme Networks
  Stephen Scearce, Cisco Systems
  Steve Pytel, Ansoft
  Syed Huq, Cisco Systems
  Syed Sadeghi, ST Micro
  Ted Mido, Synopsys
  Terry Jernberg, Cadence Design Systems
  Todd Westerhoff, SiSoft
  Vladimir Dmitriev-Zdorov
  Vikas Gupta, Xilinx
  Vuk Borich, Agilent
* Walter Katz, SiSoft
  Zhen Mu, Cadence Design Systems


Call for patent disclosure:

- No one declared a patent.

Review of ARs:

- Todd: Write IBIS s-param BIRD
  - No update

- Arpad:  Write parameter passing syntax proposal (BIRD draft)
          for *-AMS models in IBIS that is consistent with the
          parameter passing syntax of the AMI models
          - TBD

- TBD:    Propose a parameter passing syntax for the SPICE
          - [External ...] also?
          - TBD

- Arpad:  Review the documentation (annotation) in the macro libraries.
          - Deferred until a demand arises or we have nothing else to do

New Discussion:

Arpad showed the IBIS-Interconnect-SPICE document "purgatory" page:
- Arpad: Should we keep Frequency Response Table?
  - We should drop Frequency Response Table but drop Foster
- Mike: What is our philosophy for deciding what to drop?
  - We keep it if needed to describe interconnect
  - We drop if hard to implement in some simulators

Walter showed the IBIS-Interconnect-SPICE document W-element page:
- Walter: HSPICE formally recommended against the RLGCFILE param
  - Arpad: Is there a path for existing files?
  - Walter: It will work in HSPICE
- Arpad: Our specification attempts to be simulator independent
  - Walter: We don't have to spread a format that has limited use
- Radek: We should have the freedom to not implement this
- Randy: Cadence can write these out for PCB nets
  - This could easily be fixed with scripting

Shunt Element page:
- Walter: Some people use .connect
  - Mike: We may as well keep it
    - V and .connect are easily interchangeable

.SUBCKT page:
- Walter: We do not want V(node) in param expressions

S-element and S .MODEL page:
- Walter: HSPICE only supports one node order for s2p data
  - It should be easy to convert these to TS2
- Walter added "mixedmode" and "datatype=<D1D2C1C2>" params to S-param
  - Arpad: Aren't we trying not to add new things yet?
  - Walter: This was in there before, but was removed
- Radek: We should support TS2 files but avoid special features for TS1
  - Walter: This is needed to support any TS1 file
  - There was agreement that pressure to use TS2 is good
  - Walter: TS1 will be around for a long time
- Bob: The formats supported are TS and internal table
  - Internal table supports single ended and mixed mode
  - Have not seen a TS1 file for mixed mode
- Walter: S-params contain transfer functions with no mode declaration
  - There are mixed mode TS1 files
  - Bob: They do not comply with any spec
  - Walter: They have the node order in comments
  - Radek: TS1 does not really support mixed mode
- Bob: Support adding "mixedmode", but only for TS2
  - We should support the HSPICE external call
- Walter: If the TSTONEFILE param is present it is a TS2 file
  - NODEMAP gives where the near and far end pins are
    - For example: N N N F F F or N F N F N F
  - The datatype param maps between differential and single ended arrangements
- Walter: TS2 does not have node naming
  - Bob: The names are given in the S element call line
  - Walter: It needs to be in the definition, not the instance
- Radek: Are all node arrangements shown here?
  - Walter added an s2p configuration for diffpairs
    - 4 nodes, N=2
  - Radek: We can have 8 nodes?
    - Walter: We can have 8 nodes with N=4

Mike: We avoided showing the full HSPICE doc text to save time
- The idea was to not review the full HSPICE document
- But in it's absence we have had to spend time to clarify things anyway

Walter: We could copy selected whole pages from the HSPICE PDF into an appendix
- This would avoid having to use FrameMaker
- Arpad: Did we get a response from Synopsys?
  - We don't know
  - They would have responded to Todd
- Arpad: Using HSPICE pages we would have their headers and footers
  - Walter: We can black out portions
  - Arpad: That would not look good
- Bob: We could pay someone to create a document of our own
- Bob: There will be newer HSPICE doc versions
  - Walter: The way we document it will show the changes in HSPICE
  - Arpad: HSPICE changes will not automatically be part of our spec
- Bob: Standards usually have to be publication quality documents
- Arpad: It is up to Synopsys as to whether they allow their copy to be used
- Bob: We don't want to preclude the option of tracking HSPICE updates
  - If they come out with new TS2 support we may want to use that
- Walter: EDA vendors only need the minimal info we already have
  - Arpad: We tend to go from memory, and may get it wrong
  - Walter: Companies know how to write this today.
  - Bob: We could simply refer to the HSPICE document
    - We might want to pull in things like Laplace forms, however
  - Arpad: Things as simple as default units might be mistaken
- Mike: We probably have to create a marked copy of the HSPICE doc anyway
  - That could be used to create a formal document
  - We could make both available
  - Agree with Walter that people like to know what the differences are

Arpad: We will pick this up next week

Next meeting: 31 March 2009 12:00pm PT


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