MM,
Termination at reference impedance allows matrix reduction.
Suggested re-write:
Only two options for unused port termination treatments should be
permitted in the Interconnect model specification:
1) Keep unterminated ports open;
2) Terminate the ports before simulation with their corresponding
reference impedances from the Touchstone file, this allows more elegant
mathematical reductions in the matrix data before use
Walter
Walter Katz
<mailto:wkatz@xxxxxxxxxx> wkatz@xxxxxxxxxx
Mobile 303.335-6156
From: ibis-macro-bounce@xxxxxxxxxxxxx
[mailto:ibis-macro-bounce@xxxxxxxxxxxxx] On Behalf Of Mirmak, Michael
Sent: Wednesday, October 4, 2017 12:40 AM
To: IBIS-Interconnect (ibis-interconn@xxxxxxxxxxxxx)
<ibis-interconn@xxxxxxxxxxxxx>; IBIS-ATM (ibis-macro@xxxxxxxxxxxxx)
<ibis-macro@xxxxxxxxxxxxx>
Subject: [ibis-macro] Conclusions regarding unterminated ports from
today's meeting
Based on the discussion in today's IBIS-ATM meeting, is the following
summary of our next steps for Interconnect termination treatments correct?
Only two options for unused port termination treatments should be
permitted in the Interconnect model specification:
1) Keep unterminated ports open; this allows brute-force termination of
ports, or more elegant mathematical reductions in the matrix data before
use
2) Terminate the ports before simulation with their corresponding
reference impedances from the Touchstone file
To ensure the model-maker has nominal control of the termination
treatment, Unused_Port_Termination should be reintroduced as a parameter,
but as a required one. It should also have a different structure, with
only two possible arguments:
Unused_port_termination = <open | reference>
If supported, this is parse-able and checkable, but as with many other
parameters, an EDA tool could allow the user to override the setting; this
would violate the spirit of the specification but would not result in a
checkable violation of the syntax.
* MM
