Minutes, IBIS Quality Committee

18 September 2012

11:00-12:00 EST (08:00-09:00 PST)

ROLL CALL

Cisco Systems:                      Tony Penaloza
Ericsson:                           Anders Ekholm
Green Streak Programs:              Lynne Green
Huawei Technologies:                Guan Tao
IBM:                                Bruce Archambeault
                                    Greg Edlund
IOMethodology:                    * Lance Wang
Mentor Graphics:                    John Angulo
Micron Technology:                  Moshiul Haque,
                                    Randy Wolff
Nokia Siemens Networks:             Eckhard Lenski
QLogic Corp.:                       James Zhou
Signal Consulting Group:            Tim Coyle
Signal Integrity Software         * Mike LaBonte
Teraspeed Consulting Group:       * Bob Ross
Texas Instruments:                  Pavani Jella

Everyone in attendance marked by *

NOTE: "AR" = Action Required.

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

Call for opens and IBIS related patent disclosures:

- None

AR Review:

- Eckhard test Open_sink AMI model with different [Voltage Range] values
  - No report

New items:

Lance showed Waveform Comparison and S2IBIS3 Roadmap:
- slide 4:
  - Lance:
    - Need to look at:
      - Horizontal vs. vertical measurements
      - Difference peak and difference average measurements
    - Two different regions can have the same area but different shapes
    - The index is a percentage value
  - Bob: The horizontal has to be shifted to make vertical measurements?
  - Lance: Yes
- slide 5:
  - Lance: The same time window must be used for both
- slide 6:
  - Lance: The average is computed over a specific window
- slide 7:
  - Lance: The timing difference area is calculated between the thresholds
  - Bob: It could be 20% and 80%
  - Mike: Golden waveforms are really for drivers only
    - There is no absolute time for IBIS drivers
    - Would this provide a way to decide how much to shift?
  - Lance: The average time offset could be used
  - Bob: With measured waveforms the shifts are different than SPICE
  - Lance: Some use a clock as the basis to decide how much lead time to chop off
    - Most people care more about shape than timing difference
  - Mike: I often compare entire PRBS sequences
    - The time shift is adjusted to minimize total difference
  - Lance: Usually lining up the first edge works
- slide 8:
  - Lance: We would not want to use the beginning portion of this
- slide 10:
  - Mike: The red difference waveforms should how large the V difference can be
    when slope is high
    - What is 97% based on?
  - Lance: It is based on the swing on the golden waveform
    - DAI under 10% is usually good
    - If both DAI and DPI are small the waveforms probably line up well
  - Mike: Is there a horizontal difference measurement for this?
  - Lance: That was used for shifting

- Mike: We might produce a set of waveforms for testing purposes
  - This would have pairs of waveforms with different types of errors
    - DC offset
    - duty cycle distortion
    - ringback
    - overshoot
    - slope
- Bob: What does this tool do if the DC voltage is off?
- Lance: That shows up directly in DA
- Bob: One approach is the start with an idealized waveform with sharp edges
  - Then make specific measured alterations to it
- Mike: That could be done in a spreadsheet
- Bob: Anders might have done that
  - Bruce Archambeault might have done something similar
- Mike: That IEEE technique is not really feature selective at all
- Lance: Voice recognition systems often use that technique
  - David Banas has made FSV proposals
- Bob: Is this proprietary?
  - Lance: I need to check on that
    - We did file a patent

Lance: We should have an IBIS Quality presentation for the Asia summits
- Mike: We might adapt a short presentation I did recently

Bob: We may want to discuss next time whether this group still has critical mass

AR: Mike produce starter set of test waveforms

AR: Lance check on patent status for correlation methods

Next meetings:
- Next meetings Oct 2 and Oct 16

- Meeting ended at 12:16 ET
