Walter, If I would summarize this, you are basically saying that for I-V and V-t curves IBIS_min = AMI_slow and IBIS_max = AMI_fast and for C_comp either the tool or the user can decide what they pick for AMI_slow and AMI_fast. And once C_comp_corner (or anything similar) is available in the spec, that new parameter will take care of this by having the proper definition for IBIS_slow and IBIS_fast (which doesn't exist today). It seems that this would solve the "align implicitly to slow and fast corners" in the AMI specification, because it provides a definition for an AMI Format Corner parameter to be associated with the EDA tool's analog model corner. But this still leaves the ambiguity open about which C_comp value (min/max) should be used with AMI_slow and AMI_fast. You might say that AMI models do not use analog models with C_comp anyway, but there are quite a few non-Opal (i.e. IBIS compliant) IBIS-AMI models out there for which it would be nice to know how these associations should be made... My proposal spelled out what the association is with the current C_comp as well as the 5-corner version of C_comp (whether it goes with my syntax or Bob's is just another small detail). Thanks, Arpad ============================================================= From: ibis-macro-bounce@xxxxxxxxxxxxx [mailto:ibis-macro-bounce@xxxxxxxxxxxxx] On Behalf Of Walter Katz Sent: Wednesday, October 12, 2011 10:29 AM To: IBIS-ATM Subject: [ibis-macro] AMI Corner, and IBIS C_Comp, one more time All, I think AMI format Corner is well understood, although one could change the following lines: | Note that in the context of Algorithmic Model for type 'Corner', <slow | value> and <fast value> align implicitly to slow and fast corners, and | <slow value> does not have to be less than <fast value>. For type 'Range' | and 'Increment', <min value>, <max value> does not imply slow and fast | corners. To say, Note that in the context of Algorithmic Model for format Corner, <typ value> <slow value> and <fast value> shall be the values used when the IBIS Analog Model that is being used to generate the Impulse Response of the channel shall use the IBIS analog model that corresponds to the derivation methods as described for typical, slow-weak and fast-strong respectively in section 9 of IBIS. For C_comp (where C_Comp_Used is the value used in the simulation): * If an IBIS model has just C_comp the User/EDA tool shall choose a value of C_Comp_Used from the values of C_comp when simulating typical, slow-weak, or fast-strong IV and VT data. Although it is common practice (but not required) to use the min value of C_comp for fast-strong IV and VT data and C_comp max for slow-weak IV and VT data. * If a model has C_comp and C_comp_corner, then the User/EDA tool shall choose either a value of C_Comp_Used from the values of C_comp in accordance with the previous paragraph, or use the typ, min, max value of C_comp_corner when simulating typical, slow-weak, or fast-strong IV and VT data respectively. This defines a default method of defining C_Comp_Used when C_comp_corner is not defined and when C_comp_corner is defined. C_comp_corner is defined the User can direct the EDA tool to use the values of C_comp_corner that correspond to the derivation methods of the IV and VT tables, or use the values of C_comp either correlated or independent of the IV and VT tables used. Walter Walter Katz wkatz@xxxxxxxxxx<mailto:wkatz@xxxxxxxxxx> Phone 303.449-2308 Mobile 720.333-1107