IBIS Macromodel Task Group

Meeting date: 17 February 2009

Members (asterisk for those attending):
  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
  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
  Joe Abler, IBM
* John Angulo, Mentor Graphics
  John Shields, Mentor Graphics
  Ken Willis, Cadence Design Systems
  Kumar
  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
  Terry Jernberg, Cadence Design Systems
  Todd Westerhoff, SiSoft
  Vikas Gupta, Xilinx
  Vuk Borich, Agilent
* Walter Katz, SiSoft
  Zhen Mu, Cadence Design Systems

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Opens:

Arpad: Minutes for several meetings have not been posted.
- Mike: They were uploaded today but email has not been sent yet.

Walter: You can't measure DC with a TDR (related to last week)
- DC measurements should not be associated with s-params
- Arpad: Can DC numbers be added if measured by ohm meter?
  - Walter: Believe so

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Call for patent disclosure:

- No one declared a patent.

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Review of ARs:

- Walter: Invite IC vendors to meeting in 2 weeks using ibis-list
  - Not confirmed that Adge can join us.
  - Todd will send email once confirmation is received

- 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

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New Discussion:

Review of IBIS Interconnect SPICE document:
- Shunt element:
  - Arpad: There is a .connect statement that equates nodes
  - This can not be used for current measurement
  - Other options:
    - V=0
    - R=0
    - R=small number
      - Arpad: This can cause errors
  - Arpad: We already have R, we don't need to repeat it here
  - Bob: Do we really need .connect?
  - Arpad: .coonect is consistent with the idea that we have no V sources
    - Maybe we should drop V
    - Walter: Many existing SPICE decks would fail
      - Bob: Agree
    - Arpad: But V is limited to 0 here, not a full V element
- Radek: Optional explicit parameter names are not good
  - If we have named parameters maybe they should be required
- Walter: We have a philosophical difference here
  - We are simply defining a subset of HSPICE for interconnect
- Michael M: The only question we had was over dependent sources
  - This is for interconnect only
- Arpad: Is the V=0 element a subset of HSPICE?
  - Michael M: We have trouble when we take away functionality
- Mike L: Do we specify what happens with "R1 1 2 R=5 6" ?
- Arpad: Do we explicitly exclude variable names for parameters?
  - Walter added a note about this

- T element:
  - Walter: Should we require that refin and refout nodes be 0?
    - Arpad: Sometimes the only requirement is same DC potential
    - Arpad: We have no voltage sources anyway
      - Walter: The nodes could be passed in
    - Radek: Why the limit on refnodes?
      - Arpad: All 4 nodes are there, but the refnodes have limited use
    - Mike L: All simulators should be able to handle arbitrary refnodes
      - Walter: Haven't seen any circuits using it
      - Arpad: The voltages can not differ in reality
  - Walter: Should we allow both Z0 and Zo? (oh)
    - Walter: Yes
    - Arpad: As long as HSPICE supports it
  - Walter: Td is actually time per meter, with separate L parameter
    - L defaults to 1 meter
    - We will not allow L=

- E, F, G, H
  - Walter: Every combination of V/I control/source
  - Behavior is basically the same
  - Variations on the simple elements:
    - DELAY
    - LAPLACE
    - POLE-ZERO
  - Arpad: HSPICE has a frequency table version of LAPLACE and POLE-ZERO
    - There are also s-param and W elements
    - Walter: Length seems meaningless on s-param
    - Do we need LAPLACE and POLE-ZERO?
  - Arpad: Only the E element is shown, is that all we have?
    - Walter: No we have all 4
    - Some parameters described do not apply to all 4
    - The full descriptions of all 4 will be selective
  - Frequency Response table is on the next page
    - This settles the previous question about s-param and W element
    - Bob: Usage of this table might not be standardized
  - Should we keep Foster Pole-Residue?
    - The usage is not well known
  - We decided to put Frequency Table and Foster Pole-Residue in "purgatory"

- S-element
  - We will pick up here next meeting

Next meeting: 24 February 2009 12:00pm PT

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