Minutes, IBIS Quality Committee

26 Aug 2008

11-12 AM EST (8-9 AM PST)

ROLL CALL
  Adam Tambone
* Anders Ekholm, Ericsson
  Barry Katz, SiSoft
  Benny Lazer
  Benjamin P Silva
  Bob Cox, Micron
* Bob Ross, Teraspeed Consulting Group
  Brian Arsenault
  David Banas, Xilinx
* Eckhard Lenski, Nokia Siemens Networks
  Eric Brock
* Guan Tao, Huawei Technologies
  Gregory R Edlund
  Hazem Hegazy
  Huang Chunxing, Huawei Technologies
  John Figueroa
  John Angulo, Mentor Graphics
  Katja Koller, Nokia Siemens Networks
  Kevin Fisher
  Kim Helliwell, LSI Logic
  Lance Wang, IOMethodology
  Lynne Green
* Mike LaBonte, Cisco Systems
  Mike Mayer, SiSoft
  Moshiul Haque, Micron Technology
* Pavani Jella, TI
  Peter LaFlamme
  Randy Wolff, Micron Technology
  Radovan Vuletic, Qimonda
  Robert Haller, Enterasys
  Roy Leventhal, Leventhal Design & Communications
  Sherif Hammad, Mentor Graphics
  Todd Westerhoff, SiSoft
  Tom Dagostino, Teraspeed Consulting Group
  Kazuyoshi Shoji, Hitachi
  Sadahiro Nonoyama

Everyone in attendance marked by *

NOTE: "AR" = Action Required.

-----------------------MINUTES ---------------------------
Mike LaBonte conducted the meeting.

Call for patent disclosure:

- No one declared a patent.

AR Review:

- Mike rewrite 5.3.13-14

- Anders create example IBIS file with golden waveforms
  - Made a single ended model so far.
  - Want to compare to actual simulation results.
  - Will produce a spreadsheet file for posting.

New items:

IQ spec 1.1ag has significant changes and has not been posted

AR: Mike post IQ spec 1.1ag to website

Continued review of the IBIS Quality Specification:

5.3.13.	{LEVEL 2}  Clamp I-V behavior not double-counted
- Anders: Sometimes clamp tabless contain current in the operating region
  - This is Pullup/Pulldown current, not on-die termination
  - Ran into this recently
  - Does IBISCHK check this?
    - Bob: Probably would report I/V-V/T mismatch
    - IBISCHK uses combined tables for this
- We will revisit this check if IBISCHK does not detect operating region
  double counting

AR: Anders make model to test if IBISCHK detects double-counted Pullup/Pulldown

5.3.14.	{LEVEL 2}  On-die termination modeling documented
- Mike has added one sentence mentioning the use of [Add Submodel].
- We approved this check as written.

5.3.15.	{LEVEL 2}  ECL models I-V tables swept from -Vdd  to +2 Vdd.
- Mike: Is Vdd well defined for ECL?
  - Bob: IBIS  specifies -2V to Vdd.
  - For IBIS ECL Vdd is the non-negative voltage.
  - Bob: IBIS defect, no need to define [PullDown Reference]
    - Only [GND Clamp] needs it.
- If ECL operates with -2V and 5.2V:
  - [Voltage Range] would be 0
  - [GND Clamp] would be -5.2
- This may apply to LVDS also.
- We added clarification on what Vdd means for ECL.
- We added clarification on departures from the IBIS spec.

5.3.16.	{LEVEL 2} Point distributions in IV curves should be sufficient
- Mike: Is "points of inflection" defined well enough?
  - Bob: Yes.
- Pavani: In lab measurements current limits make it difficult to get 10 points
  - Often have a 10mA limit using analyzer.
  - Bob: Normally use 100mA limit.
  - Somtimes use 2 sweeps.
- Bob: Don't need accurate modeling of the high currents
  - We build models for simulation, not for accurate modeling.
- We approved this check as written.


Pavani: Some drivers can't be disabled, can't separate clamp currents
- This can happen with bench measurement.
- Mike: Some models seem to have algorithmic separation by voltage range
  - Bob: Arpad's tool tends to produce this.
  - Some devices actually behave this way.

Next meeting:

02 Sep 2008 11-12 AM EST (8-9 AM PST)

Meeting ended at 12:12 PM Eastern Time.