Arpad, "Also, I am not sure I like the idea of waiting for IC vendors to give us an indication for a certain need before we start discussing how that need could be supported in the specification." It's always a good idea to look down the road. However, if our work as a committee is not customer driven, then we may look back a year from now and find that we did a lot of work on something that only one or two people decided to use. I'm reminded of my own work on accuracy at a time when users were struggling to get models to run at all. What I hope we can do is quickly come up with a list of the top two or three big ticket items that people are really clamoring for and then develop a set of actions and milestones to tackle them. How can we generate that list? Greg Edlund Senior Engineer Signal Integrity and System Timing IBM Systems & Technology Group 3605 Hwy. 52 N Bldg 050-3 Rochester, MN 55901 From: "Muranyi, Arpad" <Arpad_Muranyi@xxxxxxxxxx> To: IBIS-ATM <ibis-macro@xxxxxxxxxxxxx> Date: 09/06/2012 10:00 AM Subject: [ibis-macro] Re: Package and on-die modeling Sent by: ibis-macro-bounce@xxxxxxxxxxxxx While I like the idea of a structured plan, I am not sure I agree with the content of the plan below. The problem I see here is what I mentioned many times before. The plan below is based on specific features and sub-features, when a single syntax could support everything. I feel we are boxing ourselves in by addressing features and usage models one at the time. All we need is a specification that allows the user to define, instantiate and connect their interconnect models. Whether they are representing a signal trace or power, coupled or uncoupled traces, or on-die vs. package parasitics is irrelevant. It is only an interconnect no matter what it represents. We just need to provide a spec that allows the user to define it, instantiate it, and connect it. Let them decide what the purpose of it is… Also, I am not sure I like the idea of waiting for IC vendors to give us an indication for a certain need before we start discussing how that need could be supported in the specification. There is usually a huge delay between the time we start discussing a need and when it becomes available officially in the specification. In the meantime we end up having “non-compliant” solutions and models and then the discussions in the IBIS meeting start going along the lines of “everyone does it this way, so we have to do it this way in the specification”. In reality, what people might be doing could be just a “make shift” solution, based on whatever happens to be tweakable in a certain tool, using all kinds of forgeries and band aids to get it to work, but we end up putting these “ill-conceived” practices into the specification because “everyone is doing it this way”. I don’t think this is the best way of writing a specification… Thanks, Arpad ===================================================================== From: ibis-macro-bounce@xxxxxxxxxxxxx [ mailto:ibis-macro-bounce@xxxxxxxxxxxxx] On Behalf Of Walter Katz Sent: Wednesday, September 05, 2012 2:09 PM To: IBIS-ATM Subject: [ibis-macro] Package and on-die modeling All, I would like to propose the following specific package and on-die modeling plan: IBIS 6.0 Support only On-Die Tstonefile (s2p and s4p) interconnect models using the [Model] sub parameters [Tstonefile] and [Tstonefile Ports]. Support package IBIS-ISS subckts as a .ipkg file which would be in Parameter Tree format. IBIS 7.0 Support On-Die IBIS-ISS subckts as a .idie file, similar to the .ipkg file but between pads and buffers instead of between pins and pads. IBIS 7.0 Create a new EMD standard IBIS 8.0 Create a new IBISx format (.ibsx) which is .ibs in Parameter Tree format I would defer any work on IBIS-BSS until IC Vendors make a specific request for such functionality. Again, we need to be driven by IC Vendors desire and ability to supply buffer models in such a modified SPICE syntax. I point out that IBIS-AMI modeling was driven by two IC Vendors. I make the recommendation for IBIS 6.0 because IC Vendors are only delivering On-Die Tstonefile (s2p and s4p) interconnect models today. We should not create an On-Die IBIS-ISS standard until we get definitive requirements from IC Vendors. We now know the requirements for On-Die Tstonefile (s2p and s4p). If IC Vendors do give compelling reasons to implement On-Die IBIS-ISS subckts we can consider moving the implementation to IBIS 6.0, since much of the basic work will be done in the implementation of package IBIS-ISS subckts as a .ipkg file. I recommend doing the IBIS-ISS package model in .ipkg Parameter Tree format because 1. It is easily to parse 2. It is easily extensible 3. It satisfies all known requirements for package models currently being delivered 4. It will slide into the new EMD standard with minimal effort Most of the issues raise about my presentation Tuesday were on EMD and .ibsx, since these are deferred, and once I have implemented examples with additions IC Vendor supplied package models the syntax of the .ipkg file can refined and ready to be reviewed in detail and documented in a BIRD. Walter Walter Katz wkatz@xxxxxxxxxx Phone 303.449-2308 Mobile 303.335-6156