Walter, Regarding: "This what is meant by "in accordance" with corner chosen to do the simulations by the EDA tool." and: "So if you want to replace the "in accordance" sentence with", I wonder what text you are referring to, because I don't see the words "in accordance" in the debated section. I suspect you are talking about this sentence: "| Note that in the context of Algorithmic Model for type 'Corner', <slow | value> and <fast value> align implicitly to slow and fast corners, ..." I just want to be sure we are talking about the same thing... Now, as to the topic itself, regarding: "Since IBIS only defines Typ, Slow-Weak, and Fast-Strong,", while you are correct that min/max for the I-V and V-t tables (including [Ramp]) can be interpreted as "Slow-weak" and "Fast-strong", such interpretation for other parameters, most notably C_comp, doesn't exist in the spec. We are not hung up on the interpretation of the I-V and V-t tables, we are hung up on the interpretation of the complete model which includes C_comp. Based on the information in an IBIS model we simply don't know what value of C_comp should be used with the min or max I-V and V-t tables. My proposal of extending the IBIS parameters to five values is to provide a mechanism for the model maker to define what value should be used for the fast and slow conditions. These values may or may not be the same as the min or max values. I would make them optional, and in the case they are not present, the assumption would be that min=slow and max=fast. For example, if someone writes: | variable typ min max C_comp 7.0pF 5.0pF 9.0pF 5.0pF should be used for a slow corner simulation and 9.0pF for a fast simulation. But if someone writes: | variable typ min max slow fast C_comp 7.0pF 5.0pF 9.0pF 8.9pF 5.1pF Than a slow corner simulation should use 8.9pF and a fast corner simulation should use 5.1pF. This approach would not break old models, but would allow new models to define the fast/slow corners for the analog models as well. This approach could be extended to all IBIS parameters which are treated independently from the I-V and V-t curves. Thanks, Arpad ============================================================== From: ibis-macro-bounce@xxxxxxxxxxxxx [mailto:ibis-macro-bounce@xxxxxxxxxxxxx] On Behalf Of Walter Katz Sent: Tuesday, October 04, 2011 7:25 PM To: IBIS-ATM Subject: [ibis-macro] IBIS is very clear about Typ, Slow-Weak, and Fast-Strong in section 9. All, Section 9 of IBIS clearly defines Typ, Slow-Weak and Fast-Strong IBIS states: It is permissible to use slow, weak components or models to derive the data for the "min" column, and to use fast, strong components or models to derive the data in the "max" columns under the corresponding voltage and temperature derating conditions for these columns. And The voltage and temperature keywords and optionally the process models control the conditions that define the "typ", "min", and "max" column entries for all I-V table keywords [Pulldown], [Pullup], [GND Clamp], and [POWER Clamp]; all [Ramp] subparameters dV/dt_r and dV/dt_f; and all waveform table keywords and subparameters [Rising Waveform], [Falling Waveform], V_fixture, V_fixture_min, and V_fixture_max. The words "permissible" and "optionally" are generally assumed by model makers and model users that at least for [Voltage Range], and [Temperature], IV Curves, VT Curves, and dV/dt all associate the Typ, Min, and Max columns with Typ, Slow-Weak and Fast-Strong. An AMI parameter with Format Corner simply states that its value to be chosen by the EDA tool should correspond to the IBIS corner of the IBIS analog model when generating the Impulse Response of the channel. This what is meant by "in accordance" with corner chosen to do the simulations by the EDA tool. Since IBIS only defines Typ, Slow-Weak, and Fast-Strong, then the three Format Corner values correspond to Typ, Slow-Weak, and Fast-Strong. So if you want to replace the "in accordance" sentence with The three values of an AMI Corner parameter value shall be chosen to correspond to the IBIS corner of the IBIS analog model when generating the Impulse Response of the channel. Walter Walter Katz wkatz@xxxxxxxxxx<mailto:wkatz@xxxxxxxxxx> Phone 303.449-2308 Mobile 720.333-1107