================================================================================ IBIS INTERCONNECT TASK GROUP http://www.ibis.org/interconnect_wip/ Mailing list: ibis-interconnect@freelists.org Archives at http://www.freelists.org/archive/ibis-interconn/ ================================================================================ Attendees from April 8, 2020 Meeting (* means attended at least using audio) ANSYS Curtis Clark* Cadence Design Systems Bradley Brim Intel Corp. Michael Mirmak*, Ifiok Umoh Keysight Technologies Radek Biernacki Mentor, A Siemens Business Arpad Muranyi* Micron Technology Justin Butterfield*, Randy Wolff* SiSoft Walter Katz*, Mike LaBonte Teraspeed Labs Bob Ross* Michael Mirmak convened the meeting. No patents were declared. Justin Butterfield took minutes. Review of Minutes: - Michael called for review of the minutes from the April 1, 2020 meeting. Randy Wolff moved to approve the minutes. Bob Ross seconded. The minutes were approved without objection. Review of ARs: - None. Opens: - Randy noted we could look at the example figures and syntax he has to add to the BIRD. EMD Draft Review: Michael asked if there were any additional documentation on the NA for EMD Parts discussion. Bob noted he also has comments regarding the definition of POWER, GND and NC for the EMD Pin List. He suggested to copy the definitions of these from the IBIS 7.0 specification. NC can be used for pins not defined by any function in the IBIS specification. These are reserved names for the power, ground and no connects. Walter Katz proposed to use NA if a part has no IBIS file, and asked if there were any objections to this. Bob stated this is not okay, as we need to define the pinouts of the IBIS file. Walter noted NA means there is no data available, while NC means it is a pin with no connection. Bob noted NA typically applies to data. He asked what is the issue with having a filled out IBIS file with the pinout defined. Michael asked if we are trying to deal with pathological IBIS file cases. Bob replied there is a Designator pinout and there should be an IBIS stub template connected to the board. He suggested to not use comment characters, as these are not read by the EDA tool. Walter commented, if the IBIS does not have a normal buffer for a pin, the model maker has two choices. They can create a no connect IBIS file. Or, they can have NA, and the user can add a Spice model or ignore it. Randy commented he does not see the value in forcing the model maker to create dummy IBIS files, and these cases seem to be outside what we are trying to solve with IBIS. Michael asked if we want to have a vote on this. Walter suggested Bob can submit a proposal to change the wording. Bob stated he wants the wording to reflect both cases. Walter asked Bob to propose these changes. Randy noted the text with the NA NA is not in the current draft. Bob to propose changes to the EMD Parts language [AR]. Bob proposed, on page 9 where POWER, GND, and NC are defined, to change the definitions to match the IBIS 7.0 specification. Bob to propose changes to the EMD Pin List section [AR]. Walter noted he has an example in the EMD Parts section with NA NA in the text he sent out over email. Bob noted he will support this, but he does not support the comment as being read by the EDA tool. Randy asked how we want to handle the example for this section and the comments for this syntax. Bob noted the comment is for information. Randy suggested having a generic part with the NA NA syntax. Michael asked if there are any additional comments on draft 5. Bob noted there were some questions on the phrase of "electrical model" vs. "interconnect model". Michael asked if the changes were accepted from the previous draft. Bob noted he did not accept the changes from draft 4. Randy thought the changes in the previous drafts from himself and Walter had been accepted. Bob noted, in section 13.6, we need a significant rewrite to remove forward references. He noted we may need to bring in additional rules such as Aggressor_Only rules in as a separate subsection. Michael asked who should handle this editorial work. Bob will rewrite section 13.6 [AR]. Bob commented we may want to add Randy's pictures in this section as well. Bob asked if this will be draft 6. Michael asked if there are any other changes needed for draft 6. Walter noted the EMD Parts text needs to be added. Bob noted he will merge the proposals and list the possibilities. Randy shared the latest examples and figures. He is still working to update the examples with the EMD Parts and Voltage List. Randy noted, in the design file for the board database, the resistor packs have reference designators. He is looking at what would be the EMD Part, and there is a part number or a device type name which could be used. For the DRAM, there is a device type name but no part number. There could be some incomplete information in the database. Bob noted there could be issues with second sourcing from multiple component vendors with different manufacturer part numbers. Randy commented, for his example, he came up with generic part names for the EMD Parts to map to the Designators. Walter noted, when he imports a board file or an EMD, the user will have to select the IBIS files that are not mapped. Randy asked about the Voltage List, where he has a bus_label for the rails. He asked if this needs to match the bus_label or match the pin list with a VDD1. Bob replied this would isolate the VDD1. Walter commented, if VDD is split into VDD1 and VDD2, it still has the same the voltage value. He asked why do we need bus_labels on these. Randy agreed with only describing VDD in the Voltage List. Bob suggested to support bus_label in this list as well. Randy commented he plans to use only VDD. Michael asked if Randy can send out his example. Randy will send out the examples once they are updated with the latest syntax [AR]. Bob to send out draft 6 [AR]. Randy suggested to accept all changes from previous drafts in draft 6. Next Meeting: The next meeting will be April 15. Randy moved to adjourn. Curtis seconded. The meeting adjourned without objection. ================================================================================ Bin List: EMD Comments to be Resolved: (See BIRD202.1 tracking spreadsheet) IBIS-ISS Parser: - IBIS-ISS parser scope document