Minutes, IBIS Quality Committee 16 June 2009 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 Muniswarareddy Vorugu, ARM Ltd * 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 Liqun, Huawei 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 post new draft - 1.1as was posted - Mike fix font and reference issues in IQ specification identified by Anders - TBD New items: A Motorola group has contacted Mike asking for a presentation on IBIS Quality - Bob: They could join our meetings too Anders Eckholm review of the IQ 1.1 specification (2nd half): 3.1.1. {LEVEL 2} [Package] must have typ/min/max values - We had changed this in the last meeting - Moshiul: The [Package] min/max L and C do not necessarily correspond to any single pin - Bob: Worst case time delay is max L max C - Worst case impedance is max L over min C or min L over max C - May use max/max and min/min, but EDA tool can do whatever - A good practice is to find min & max of the [Pin] RLC list - Mike: We use [Package] calculated overall skew to decide when RLC is needed - Bob: We call for pin RLC in 3.3.2 - That is a level 3 check From Anders' email: 3.1.2 here we state pin parasitics should represent the range spanned by the actual pin parasitics for signal pins.. Which raises the question which return pin these parasitics are suppose to be related to ? At the end of the paragraph it clearly states that power and Gnd pins should not be included in the determination of the [Package] parasitics. Related to a discussion we had concerning defining pin parasitics for power & Gnd pins. - Anders: The return path assumption is the problem here - Bob: This has to be figured out from [Pin Mapping] - Mike: [Pin Mapping] gives just a loose pin association, is that enough? - Bob: There can be multiple loops using that same parasitic - For example, 5 returns using the same ground - A TDR measurement might be measuring the whole loop - Mike: The ATM group is working on better interconnect modeling now - Bob: Modeling is always done piecewise anyway - IBIS is extraction-centric - Mike: Should we change 3.1.2? - Anders: It is not clear what we could do - Mike: Is consideration of return paths too much detail for [Package]? - Bob: If the power and ground pins have zero LC that might have been factored into the signal pin RLC - Anders: There should be a comment about extraction - Moshiul: With some extraction tools you can not specify return paths. - They make assumptions - The mounting makes a difference - Mike: We could delete: "typically it is the average of the signal pin parasitics, but it need not be" - Also delete: "The power and ground pins should NOT be included in the determination of the [Package] parasitics" - We could add a comment calling for documentation of the method used - Moshiul: The limits L < 100nH, C < 100pF, R < 10 ohm are not reasonable - for power and ground pins - We changed it to apply only to signal pins - Mike: This IQ check calls for limits lower than IBISCHK - Bob: It would be better to not have numeric limits - But it is OK as is - The lower limits might be a CAUTION in future IBISCHK - No new draft will sent this time as there are few changes Meeting ended at 12:02 PM Eastern Time.