Minutes, IBIS Quality Task Group 31 March 2020 11:00-12:00 EST (08:00-09:00 PST) ROLL CALL Intel Corp. Michael Mirmak Mentor, a Siemens Business Arpad Muranyi Micron Technology * Randy Wolff Signal Integrity Software: * Mike LaBonte SPISim Wei-hsing Huang Teraspeed Labs: * Bob Ross Zuken USA: Lance Wang 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 Review of previous meeting minutes: Minutes from the March 24 meeting were reviewed. Bob Ross moved to accept. Randy Wolff seconded. Without objection the minutes were approved. ARs: - Bob Ross to find more up to date TSCHK2 source code license document - Done, but an updated version could not be found. We have one under review anyway. - Mike LaBonte to update IBISCHK "orphan" message sections 3, 4, and 6. - Done. - Bob Ross to reduce over-extrapolation bug testcase size and post it - Done, but will be reviewed before posting. New IBISCHK bugs: Bob Ross showed BUG211 with updates. I-V curves had been reduced to 5 points each, and precision reduced. Mike had researched the history of the decision to check for excessive currents 1.5V outside the operating range. It was part of EGG10. The 1.5V and 10A limit values were found to be outside the range seen in models at the time. Bob said there were no checks for [Pulldown] or [Pullup] tables. It could have been changed to an In model, but it wasn't. Bob had changed the data to make all 3 corners give the warning message. Bob suggested making it a caution message, but not removing the test. Another question was whether to make it apply to all [IBIS Ver]. Randy Wolff suggested fixing the extrapolation to use a valid voltage. Mike had suggested a code change for that. Bob noted that I-V curves can go beyond what is required. Mike LaBonte felt that extrapolation was not needed. We could simply find the nearest table point to 1.5V. Bob noted that it would also interpolate to 1.5V if the table extends beyond. Mike said it should be OK to interpolate, but never extrapolate. He was assuming the last points would have the highest current. Bob said the last point could be the highest, but maybe [Voltage Range] would be better. Randy agreed. Bob said the typical corner voltage should be used for all checks. Randy asked if the positive side was checked. Bob said voltages on both sides of the operating range were checked. Randy said power clamps would sometimes have a different voltage than voltage range. Mike showed his suggested code changes. Bob said all reference voltages were required if any was given. Randy said all four were required if voltage range was missing. Either [Power Clamp Reference] or [Pullup Reference] were required for power clamps. Bob felt this issue was holding up BIRD181.2 Mike said the point was to forward bias the diode and check the current. The voltage range was only a loose indication of the clamp forward bias voltage. Bob said the extent of table points should give a good indication. Mike suggested starting at 1.5V, interpolating as needed, but not extrapolating. Randy said diodes connected to references other than [Voltage Range] existed in the past but were rare today. Those reference voltages were all beyond 1.5V. Bob said he would introduce the bug at the Open Forum meeting Friday. Randy and Bob felt it should be a caution message. Mike said the original intent seemed to be to guard against forgetting to put "m" for milliamps. TSCHK2 license agreement: No discussion. Better IBISCHK error messages for BUG210: Bob said the bug report needed to be amended. AR: Mike LaBonte to update BUG210 with message update suggestions. IBIS-ISS parser: No discussion. Randy Wolff moved to adjourn. Bob Ross seconded. Without objection the meeting ended. Meeting ended: 12:08 ET Next meeting March 31, 2020