****************************************************************************** ********************* IBIS GOLDEN PARSER BUG REPORT FORM ********************* ****************************************************************************** INSTRUCTIONS To report a bug in the IBIS golden parser. Please fill out the top part of the following form and send the complete form to info@ibis.org. A list of reported bugs is maintained at http://ibis.org/bugs/ibischk/. ****************************************************************************** PARSER VERSION NUMBER: 6.1.4 PLATFORM (SPARC, HP700, PC, etc.): PC (Intel(R) Core(TM) i5-6440HQ Processor) OS AND VERSION: Microsoft Windows 10 Enterprise, Version 1607 REPORTED BY: Michael Mirmak, Intel Corp. DATE: August 29, 2017 DESCRIPTION OF BUG: The use of the Caution flag with ibischk6 on a file where [Ramp] is present but no I-V tables (i.e., [Pullup], [Pulldown], [POWER Clamp], [GND Clamp]) are present causes a caution message to appear regarding a mismatch between the Ramp dV and an I-V dV of 0.000 V. This is based on an incorrect assumption that the default dV of the buffer in the absence of I-V table data is zero. As the I-V table keywords are technically not required -- particularly when [External Model] is present -- but [Ramp] is always required, the message is misleading. Note that the use of [External Model] is not required to show the issue. However, if [External Model] is not present, additional Warnings are produced regarding the absence of [Pullup] and [Pulldown] I-V data in the [Model]. The same Cautions are produced regardless of whether [External Model] is present or not. The Caution message should be clarified, but the messages should differ depending on whether [External Model] is present. A potential replacement message for [Model] without [External Model] is: CAUTION - [Ramp] dV data cannot be compared against I-V dV, as I-V table data is not present in Model Output1 A potential replacement message for [Model] with [External Model] is: CAUTION - [Ramp] dV data cannot be compared against I-V dV, as [External Model] is used in place of I-V table data in Model Output1 The output of the demonstration file with -caution is as follows: IBISCHK6 V6.1.4 Checking bug193.ibs for IBIS 5.1 Compatibility... C1514 - [Ramp] dV ( 0.100V) not within 5.00% of I-V table dV ( 0.000V) calculation: Model Output1: Process: TYP: (Rising) C1514 - [Ramp] dV ( 0.100V) not within 5.00% of I-V table dV ( 0.000V) calculation: Model Output1: Process: TYP: (Falling) Errors : 0 Cautions: 2 File Passed ---- Added Note: Following the Caution message guidance by setting dV to 0.0 produces these correct Error messages: E1310 (line 45) - dV must be greater than 0 in a Ramp specification E1310 (line 46) - dV must be greater than 0 in a Ramp specification So there is no easy way to avoid the messages for legal IBIS models. ------ Based on discussion at the IBIS Quality TG meeting on September 5, 2017, the suggested resolution is to suppress the C1514 message when [External Model] exists under [Model] for all non-Input Model_types. INSERT IBIS FILE DEMONSTRATING THE BUG: |******************************************************* [IBIS Ver] 5.0 [File Name] bug193.ibs [File Rev] 1.0 [Date] August 29, 2017 [Source] From Michael Mirmak, Intel Corp. | |******************************************************* | [Component] BUG193 [Manufacturer] XYZ, Inc. | |******************************************************* [Package] R_pkg 1.e-03 NA NA L_pkg 1.e-09 NA NA C_pkg 1.e-12 NA NA | [Pin] signal_name model_name R_pin L_pin C_pin 1 Test Output1 | |******************************************************* | [Model] Output1 Model_type Output Vmeas = 0.5 C_comp 1.0pF NA NA | [Voltage Range] 1V NA NA | [External Model] Language SPICE | Corner Typ dummy.inc driver | Ports my_stimulus A_signal A_gnd | |D_to_A d_port port1 port2 Vlow vhigh trise tfall corner D_to_A D_drive my_stimulus A_gnd 0 1 200ps 200ps Typ | [End External Model] | [Ramp] R_load = 50.00Ohm dV/dt_r 100mV/10ps NA NA dV/dt_f 100mV/10ps NA NA | [End] ****************************************************************************** ******************** BELOW FOR ADMINISTRATION AND TRACKING ******************* ****************************************************************************** BUG NUMBER: 193 SEVERITY: [FATAL, SEVERE, MODERATE, ANNOYING, ENHANCEMENT] ANNOYING PRIORITY: [HIGH, MEDIUM, LOW] LOW STATUS: [OPEN, CLOSED, WILL NOT FIX, NOT A BUG] CLOSED FIXED VERSION: 6.1.5 FIXED DATE: December 21, 2018 NOTES ON BUG FIX: Classified at the September 15, 2017 IBIS Open Forum. To be fixed in a future release Caution Message C1516 and C1517 for the test cases described here ****************************************************************************** ******************************************************************************