
Minutes, IBIS Quality Committee

08 December 2015

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

ROLL CALL

eASIC:                              David Banas
Ericsson:                           Anders Ekholm
Intel:                              Michael Mirmak
                                    Eugene Lim
IO Methodology                    * Lance Wang
Signal Integrity Software         * Mike LaBonte
Teraspeed Labs:                   * Bob Ross

Everyone in attendance marked by *

NOTE: "AR" = Action Required.

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

Call for IBIS related patent disclosures:

- None

Call for opens:

- None

ARs:

- Mike reply to AOTO about bug report
  - Done.

- Bob update bug168.txt
  - Done, may be more on this.

- Bob update ibischk6 web page to note new bugs
  - Done.

- Mike send notice of IBISCHK6 with bug notes to email reflectors
  - Done.

- Mike send W1503 testcase to Bob
  - Needs simplification first, has 986 lines.
  - Will send to Bob as-is for now.

- Mike add comments to CMPNT, DLY, MSPEC sections.
  - No new progress.

- Lance add comments to EBD section.
  - No new progress.

- Bob add comments to CIRCUIT section.
  - No new progress.

BUG169

- Bob: This is straightforward, it just needs to be classified.

BUG168

- Mike explained the problem.
- Lance: The field solver could fix this just by changing how it prints numbers.
- Bob: Is 10ppm too small for the threshold?
- Mike: Maybe, but it's hard to determine the right tolerance.
- Bob: Vladimir mentioned 1000ppm.
  - Files with many pins might print many messages.
  - NOTEs will be printed for minor violations.
  - We could suppress NOTEs if the violation is under some lower threshold.
- Mike 100ppm might be reasonable.
  - I would rather print NOTEs for any negative case, no lower threshold to
    suppress that.
- Bob: Also the reporting needs more precision.
  - That applies to inductance and resistance too.
- Mike: The explanation in the bug document of the inductance issue is confusing.
- Bob: We decided to test for positive values only.
  - The diagonal dominance check will be disabled.
- Mike: I tried the (L * C) > 0 test that Vladimir suggested.
  - Every diagonal entry passed that test.
  - Every off diagonal failed, but that is expected.
- Bob: Vladimir was not suggesting we do that test.
- Bob showed the IBIS specification.
  - We require inductance matrix diaganol dominance.
- Mike: All we can do now is disable the test and write a BIRD.
- Bob: The key issue is whether the matrix is a transmission line.
  - That decides which tests are valid.

AR: Bob update BUG168 to clarify inductance checks

AR: Mike ask Radek for opinion on BUG168

Meeting ended: 12:08 ET

Next meeting Dec 15, 2015
