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IBIS INTERCONNECT TASK GROUP
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Attendees from January 20, 2021 Meeting (* means attended at least using audio)

ANSYS                                Curtis Clark*
Intel Corp.                          Michael Mirmak*
Mentor, A Siemens Business           Arpad Muranyi*
Micron Technology                    Justin Butterfield*
                                     Randy Wolff*
SiSoft (MathWorks)                   Walter Katz
Teraspeed Labs                       Bob Ross*
Zuken USA                            Lance Wang*


Randy Wolff convened the meeting.  No patents were declared. 
Justin Butterfield took minutes.


Review of Minutes:
- Randy called for review of the minutes from the January 13, 2020 meeting.  
  Randy displayed the minutes.  Bob Ross moved to approve the minutes.  
  Curtis Clark seconded.  The minutes were approved without objection.

  
Review of ARs:   
- Michael Mirmak to send out EMD BIRD202.2 draft6 and the bin list.
  - Done.


Opens:
- None.


BIRD202.2 draft6 and bin list review:
Randy asked if there were any comments or issues found in draft6 after the 
last meeting.  Randy noted bin list item #22 refers to a situation where 
Voltage List has different values from Voltage Range in the IBIS file.  Randy 
noted we have a statement to address this case on page 15, which states: "The 
EDA tool can override these values."  Bob agreed we wrote this override 
statement.  We might override the typical, but not the min and max.  For the 
case of an external source, the EDA tool can do what it wants.  Arpad Muranyi 
asked about the following sentence: "Because the [Voltage List] entries may be 
incomplete or because V(min) and/or V(max) values may be omitted, combinations 
of the above options are permitted."   He asked what "above" is referring to.  
Randy replied it is referring to the bullet list.  Arpad asked about the word 
"because" and suggested to change it to "since".  Randy suggested to delete 
the second "because".  Randy marked item #22 in the bin list as complete.


EMD Parts selector discussion:
Randy was not sure if we can add an EMD Parts selector into this version of 
the BIRD.  There is nothing broken currently, and this is a nice to have 
feature.  Arpad stated what we would like is to exchange an optional list of 
Components or file references.  Randy thought it would be simple to have 
multiple EMD Parts list sections.  Arpad asked how many parts would go on a 
DIMM.  Randy noted it could be a long list if you include all the resistors 
and capacitors.  Arpad noted, if it is a long list, then it could be 
repetitive to make multiple copies of it.  Randy stated he was thinking of 
this feature mostly for multi-chip packages, where you have different 
temperature and voltage grade parts.

Arpad asked if the IBIS file would not change but the Component would change.  
Randy stated this would not work for how they typically organize their IBIS 
files, with different IBIS files for temperature and voltage ranges.  Arpad 
stated, for EMD, the pinout would not change, but the voltage and temperature 
could change.  Bob noted the Component name needs to match the datasheet.  The 
other approach is to use the Model Selector to do the selection.

Arpad asked how many selectors we want to support.  Randy noted we can also 
have nested layers of EMD files and each of these could have a selector.  
Arpad thought we could remove this possibility by not allowing the selector 
for the nested EMDs.  We still need to decide if we want the IBIS file and 
Component selector or only one.  Randy stated, if we repeat the list, it could 
be simplified.  Arpad noted, if you have many combinations, there could be 
many lists.  Randy noted the list would only have the valid combinations.  
Randy commented the EMD Parts list is short for multi-chip packages, and the 
list could be easily repeated.

Randy noted it could be dangerous to have a Component selector as the pin out 
could be different between components.  Arpad asked if we should eliminate 
this possibility.  Randy replied this is an advantage of the fixed combination 
list provided by the model maker.  Arpad asked if we could allow the same part 
name to be repeated in the list and allow the user to select between those in 
the list.  Randy replied the problem with this is that only some of these 
could be valid combinations.  Bob commented one option is to repeat the 
Component, and the other option is to give the list a name.  Arpad asked if it 
is less repetitive to repeat the list or repeat the entire EMD file.  Randy 
replied it is simplest to repeat the list.  Arpad suggested we could give the 
list a name and repeat the list with a different name, but we would not need a 
selector keyword.  Bob suggested an EMD Part selector would give the EDA tool 
a description.  

Arpad asked about the nested EMD case.  He commented his earlier exclusion of 
the selection for this case would not work for multiple EMD Parts keywords.  
Randy suggested we would have to allow the selection of the EMD Parts list at 
the lower levels.  Arpad thought we would need another column in the EMD Parts 
keyword for this case.  Arpad asked if the third column in EMD Parts is being 
used for anything in the case of referencing an EMD file, since we can only 
have one Begin EMD per file.  Bob was concerned this would not be consistent 
with the rest of IBIS.  Randy asked if this would take away the selection 
mechanism.  Arpad replied that he was looking for a simple solution to this 
problem.

Arpad asked about the issue with the Voltage List keyword.  Randy replied, if 
you are selecting an IBIS file with a different Voltage Range, the Voltage 
List would no longer be valid.  Arpad asked if we should give Voltage List a 
name to match the EMD Parts.  Randy thought this could work.  Bob stated this 
would be an unusual syntax for IBIS.  Arpad commented another way would be to 
put the Voltage List inside the EMD Parts list.  Bob noted you might have 
conflicts between the IBIS files.  Arpad commented we have already dealt with 
this in the text for Voltage List.

Arpad asked if we are cornering ourselves for future enhancements without this 
feature.  Bob was against including the Voltage List in EMD parts.  Arpad 
stated we need a mechanism to apply the Voltage List to the EMD Parts list to 
have voltage variants.  Bob stated we need a simple solution, or we can live 
without this and have multiple files.

Randy will send out EMD BIRD202.2 draft7 [AR].


Next Meeting:
The next meeting will be January 27.


Bob moved to adjourn.  Arpad seconded.  The meeting adjourned without 
objection.

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Bin List:

EMD Comments to be Resolved:
(See BIRD202.1 tracking spreadsheet)

IBIS-ISS Parser:
- IBIS-ISS parser scope document