David, I think the short answer is that what you are asking for is now all officially supported by the v6.0 specification. But here are some details: #1) Yes, you can just have one [Model], and use the [External Model] with language "IBIS-ISS". This will let you implement your analog buffer model using one or more Touchstone files. You can also parameterize the IBIS-ISS subcircuit so that the name of the Touchstone file is a string parameter. This way one [Model] and [External Model] inside it and a single IBIS-ISS subcircuit can have many different S-parameter models, each of which can describe a certain buffer impedance, etc... If your signal swing needs to be changed, you can also parameterize the D_to_A converter (which acts as the stimulus to the IBIS-ISS subcircuit) using the new "Converter_Parameters" subparameter of [External Model]. All of these parameter definitions in the .ibs file can also contain references to parameter files, and if you reference a .ami file you can also synchronize these parameters with AMI model parameters. #2) This is now all in the v6.0 IBIS specification, so no proprietary solutions are needed to achieve all this. #3) This modeling approach will give you the correct results as long as the linear S-parameter model with a trapezoidal (ideal) stimulus is able to adequately describe your buffer's analog behavior. (In other words if the buffer is pretty much LTI). But that is the fundamental requirement of this entire AMI modeling approach, so if your buffer has strong non-LTI features, AMI would not be suitable anyway. I hope this answers your questions. Thanks, Arpad =========================================================================== From: ibis-macro-bounce@xxxxxxxxxxxxx [mailto:ibis-macro-bounce@xxxxxxxxxxxxx] On Behalf Of David Banas Sent: Monday, March 03, 2014 8:21 PM To: 'ibis-macro@xxxxxxxxxxxxx' Subject: [ibis-macro] On-die S-parameters? Hi Experts, Can anyone answer this one: Let's say I have a Tx with variable analog behavior. That is, things like output drive strength, output impedance, and output slew rate are user selectable, in the silicon. In that case: 1. Will the on-die S-parameters approach to analog modeling allow me to reduce the number of [Model]s in my *.IBS file to one, and make ALL model behavior, both analog and algorithmic, configurable, via some sort of AMI parameter sweep matrix in the simulator? 2. If so, is this ready to go, today, in the standard, or does it require a proprietary approach? 3. Also, will modeling this way give true channel characterization, or will I be forced to "cheat" making up for some amount of channel characterization inaccuracy in the algorithmic portion of my model? Thanks! -db ________________________________ Confidentiality Notice. This message may contain information that is confidential or otherwise protected from disclosure. If you are not the intended recipient, you are hereby notified that any use, disclosure, dissemination, distribution, or copying of this message, or any attachments, is strictly prohibited. If you have received this message in error, please advise the sender by reply e-mail, and delete the message and any attachments. Thank you.