IBIS Macromodel Task Group

Meeting date: 15 Jan 2008

Members (asterisk for those attending):
  Ambrish Varma, Cadence Design Systems
* Arpad Muranyi, Mentor Graphics Corp.
  Barry Katz, SiSoft
* Bob Ross, Teraspeed Consulting Group
* David Banas, Xilinx
  Donald Telian, consultant
  Doug White, Cisco Systems
  Essaid Bensoudane, ST Microelectronics
  Ganesh Narayanaswamy, ST Micro
  Hemant Shah, Cadence Design Systems
* Ian Dodd
  Joe Abler, IBM
* John Angulo, Mentor Graphics
  John Shields, Mentor Graphics
  Ken Willis, Cadence Design Systems
  Kumar, Cadence Design Systems
  Lance Wang, Cadence Design Systems
  Luis Boluna, Cisco
* Michael Mirmak, Intel Corp.
* Mike LaBonte, Cisco Systems
* Mike Steinberger, SiSoft
  Mustansir Fanaswalla, Xilinx
  Patrick O'Halloran, Tiburon Design Automation
  Paul Fernando, NCSU
* Radek Biernacki, Agilent (EESof)
* Randy Wolff, Micron Technology
  Ray Comeau, Cadence Design Systems
  Richard Mellitz, Intel
  Richard Ward, Texas Instruments
  Sanjeev Gupta, Agilent
  Shangli Wu, Cadence
  Stephen Scearce, Cisco Systems
  Steve Pytel, Ansoft
  Syed Huq, Cisco Systems
  Syed Sadeghi, ST Micro
* Todd Westerhoff, SiSoft
* Terry Jernberg, Cadence Design Systems
  Vikas Gupta, Xilinx
  Vuk Borich, Agilent
* Walter Katz, SiSoft

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Call for patent disclosure:

- No one declared a patent.

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Opens:

- DesignCOn presentations
  - Todd is presenting on AMI interoperation
  - Bob

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Review of ARs:

- Michael M. : Summarize options/directions in a couple of for our
  differential feature enhancements

- AMI BIRD authors meet to prove AMI BIRD can handle Mellitz cases
  - Todd reported that he and SiSoft are debating about how to disclose
    handling the linearity issues described in 2007 by Rich Mellitz.

- Mike S send non-proprietary information on studies he performed
  - ???

- EDA vendors: meet to decide differential BIRD direction
  - ???

- Michael M. sketch new IBIS interconnect plan
  - ???

- Walter coordinate completion of true diff BIRD draft
  - ???

- Michael M. draft Eye keywords for true diff BIRD
  - TBD

- Randy draft derating keywords for true diff BIRD
  - TBD

- 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:

Mike S. presented spreadsheet NonlinearReconstruction.xls:
- Addressing slide 16 from Mellitz presentation.
  - Measured data from slide with Kruler
- Shows that if tap weights other than -.21, .79 will yield close results.
- Device goes into saturation and fails to produce predicted amplitude.
- Only need to measure one pass.
- Need to measure for every EQ setting.
- Driver is non-linear but memory-less.
- There is a set of tap weights that will predict the non-linear behavior.
- Todd: engineering is about usable models, not necessarily perfection.

Michael M. presented "Advanced Differential Measurements for IBIS":
- Addresses an old AR: "Michael M. draft Eye keywords for true diff BIRD"
- Chart a direction for differential modeling
- Need to be specific about location Pin/Pad/Core
  - Todd calls this "decision point"
- There are min and max V limits outside the eye.
- USB 2.0 spec chap 7 shows how it is defined
- Keywords:
  - [Diff Receiver Measurements]
  - [Eye Template] name
  - Each has "bookend" keyword
  - Can add more to [Diff Receiver Measurements] later
- UI column in point data is dimensionless, 0.0 to 1.0

- Walter: this is defining the lower & upper eyes together
  - Could have separate columns
- Michael M: Might not allow for irregular UI axes

- Walter: Same eye patterns are used all the time
  - Data would be repeated many times
  - Should not have same eye templates in every file
  - Would be nice to include these from a separate file
- Michael M: Should we get standards orgs to create these files?
- Todd: A simple IBIS .include mechanism would solve this
- Ian: Do we reference by file or by name?
- Bob: Might have trouble keep standard file name straight.
- Walter: JEDEC could supply these along with their specs

- Walter: There are multiple Core locations that Probe_location should address.
  - External model may export nodes
  - AMI model may export nodes
- Michael M: There is interest in latch-to-latch analysis

- Arpad: Walter had other parameters we might add
- Michael M: Maybe that is a separate effort
  - If we start a new group we will probably have the same people
  - Arpad: Would still prefer separate meetings
- Bob: Priority is to move forward quickly on what we have

- Walter: We should commit to a date for completing this BIRD, including:
  - single-ended
  - differential
  - Tvac
  - Tdelay
- Arpad: we need an AR
- Bob: Set "several months" as a target
- Walter: can have something after DesignCon

AR: Walter, Randy, Michael M. begin writing differential BIRD

Next meeting: 22 Jan 2007 12:00pm PT

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