Mike,
I would like more information on the debate about the value of merely passing on JEDEC limits versus the actual performance range of a part population. Your purchasing department would certainly appreciate the ability to do parts swapping. The only reason I can think of to qualify and use a model for the actual performance of a single supplier would be if I were going to try to optimized the performance of an interface for a specific design. This would also mean I might have to pay more for that part due to sole source, non-competitive pricing.
IMHO, generic waveforms have less value than in the past. As buffers are being pushed to switch faster, they are inherently becoming more linear. Last time I needed a waveform was to model an intentional non-linearity that the supplier introduced in a pull-down to slow the part down so it would meet the fall time spec.
Another value for the users of the specification would be that the specification would be more likely to be complete and realistic. I have seen specs in the past that had holes and non-overlap. I think I even remember one that allowed a Vol higher than the Vil....
As far as the testing goes, I'm fairly sure that would NOT be a problem. Indeed, the spec models would probably be tested multiple times by the multiple users. Some of us want our products to be robust so we try to break things... :-) Certainly I would spend some time verifying and validating any model I used.
I, for one, would like us users to push back on any new interface specification that did not include buffer models and test setup. Most suppliers already do demo boards -- why not models? This gets me back to one of my favorite platitudes: "A measurement for every model and a model for every measurement. Without both, I don't believe either."
Aubrey Sparkman
512-461-6165
asparky@sparkright-solutions.com
-----Original Message-----
From: owner-ibis-users@eda.org [mailto:owner-ibis-users@eda.org] On Behalf Of Nikonchuk Sergey-R6294C
Sent: Thursday, April 08, 2010 10:42 AM
To: Mike LaBonte (milabont); Aubrey Sparkman; si-list@freelists.org; ibis-users@eda.org
Cc: steve weir; Lynne D. Green; colin_warwick@agilent.com
Subject: RE: [IBIS-Users] RE: [SI-LIST] Re: Straw poll and call for comments: Crowdsource IBIS model directory by use of a wiki such as wikipedia?
I am quite new IBIS models developer, but I am fully support idea of Reference IBIS models for standard interfaces.
It would be really helpful to align our product/technology specific models to the Standard Requirements, expectations, specifications.
And verify them accordingly.
Regards
Sergey Nikonchuk
Characterization and View Generation
TSO / DT / DC / IO Libraries
www.freescale.com
Phone: +7 (495) 589 1839
Mobile: +7 (916) 993 3467
-----Original Message-----
From: owner-ibis-users@eda.org [mailto:owner-ibis-users@eda.org] On Behalf Of Mike LaBonte (milabont)
Sent: Thursday, April 08, 2010 7:33 PM
To: Aubrey Sparkman; si-list@freelists.org; ibis-users@eda.org
Cc: steve weir; Lynne D. Green; colin_warwick@agilent.com
Subject: RE: [IBIS-Users] RE: [SI-LIST] Re: Straw poll and call for comments: Crowdsource IBIS model directory by use of a wiki such as wikipedia?
The IBIS Quality spec goes beyond IBISCHK. There was some discussion at one point about having the IBIS Models page somehow indicate IBIS Quality adoption, but no agreement on a fair way to do it resulted.
I like the idea of spec-based IBIS models, even if they are incomplete templates. I find that parts made to JEDEC specs, for example, sometimes omit data like [Receiver Thresholds] from their IBIS files. Some data are absent even from the datasheets, as though a reference to the JEDEC spec should suffice.
There is an interesting debate about the value of merely passing on JEDEC limits versus the actual performance range of a part population. And there may be no great way to produce generic waveforms for a spec-standard IBIS model. If something reasonable can be produced, Aubrey has an interesting point that such an IBIS model might be used to verify that a design should work with any spec-compliant part, without simulating the separate IBIS files from each vendor.
In any event I think if organizations like JEDEC produced IBIS files for each spec they would be doing everyone a favor. Some elements could be lifted from them, and they could provide a reference for limit checking vendor-specific IBIS models. Maybe anyone could contribute these spec-standard models, but who would verify that they accurate reflect the specs?
Mike
-----Original Message-----
From: owner-ibis-users@eda.org [mailto:owner-ibis-users@eda.org] On Behalf Of Aubrey Sparkman
Sent: Tuesday, April 06, 2010 9:18 PM
To: si-list@freelists.org; ibis-users@eda.org
Cc: 'steve weir'; 'Lynne D. Green'; colin_warwick@agilent.com
Subject: [IBIS-Users] RE: [SI-LIST] Re: Straw poll and call for comments: Crowdsource IBIS model directory by use of a wiki such as wikipedia?
I like the idea of crowdsource, but I DON'T agree that parser clean is sufficient. I've seen too many models that pass parser but have curves that are not realistic.
While many of the IBIS models I've used in the past have been considered IP, there is a class of models that would be very valuable and not subject to IP. Back in the day, I made a model for a generic PCI-X buffer model that reflected the PCI-X buffer specification. Using that model was, in most cases, preferable to using supplier specific buffer models because it enabled me to claim that any suppliers' product that met the PCI-X specification would work in my system.
Does anyone volunteer to create spec based models for the current interfaces such as PCIe-GenX, USB-x, SATA, SAS, etc?
Aubrey Sparkman
512-461-6165
asparky@sparkright-solutions.com
-----Original Message-----
From: si-list-bounce@freelists.org [mailto:si-list-bounce@freelists.org] On Behalf Of steve weir
Sent: Tuesday, April 06, 2010 6:51 PM
To: si-list@freelists.org
Cc: ibis-users@eda.org
Subject: [SI-LIST] Re: Straw poll and call for comments: Crowdsource IBIS model directory by use of a wiki such as wikipedia?
The IBIS organization is a natural place to maintain a catalog and records of any checks done by vendors: silicon and/or EDA.
The market value to the EDA vendors would be the ability to state the breadth of models that their tools support which might have enough market value to justify the ongoing cost. I would expect that the effort to create automated or semiautomated checking for compatibility would be well within the capability of each EDA vendor and make the amortized cost quite low. I think for any scheme to stand a chance of market acceptance, it cannot impose any substantial additional cost in dollars and/or time on silicon vendors.
Best Regards,
Steve.
Lynne D. Green wrote:
>
> Steve and Colin,
>
> The "neutral" third party could be the IBIS Model Review Committee
> (who are representatives from EDA vendors). We could perhaps report
> models that pass the parser with no errors and no warnings. Someone
> could encourage vendors to post their parser output file, with
> comments about why particular warnings/errors were accepted, but that would be the vendor's job.
>
> Nothing "bad" would be reported about a particular IBIS file. And
> only reporting "parser clean" might help address Jon's (very true)
> point about IP protection. (And more vendors might take advantage of
> our "neutral" review service to get on this list.)
>
> Another useful thing on the "wiki" might be educational material:
> articles and educational materials people contribute, links to IBIS
> parser, specs, cookbook, etc.
>
> Cheers,
> Lynne
>
> Lynne Green
> Chair
> IBIS Model Review Committee
>
>
> steve weir wrote: Colin, I don't see an open community Wiki-like
> structure ever getting vendor support. There is just too much exposure
> to unchecked, and potentially unfounded or even malicious criticism.
> We do not live in suchan egalitarian society that vendors locked in
> tight competition might nottry and get an edge in new product adoption
> by spreading FUD over their competitor's offerings. In a world where
> NDA's are required just to obtain data sheets I find it nearly
> impossible to believe vendors would expose themselves in such a public
> and difficult to control way. I think that if anything is going to come of this it would have to be either of the form of:
> a. Voluntary vendor disclosure of standards compliance or b. Vendor
> participation in compliance testing by an accepted neutral third party
> such as a standards committee (as neutral as those can be). Best
> regards, Steve colin_warwick@agilent.com[1] wrote: Hi Jon, Yes, IP and
> updates are an issue,so the plan is to let IC vendors build a
> directory of links and/or "how-to-get-the-model" instructions, not the
> models themselves. Users will add reviews and ratings and IBISCHK
> scores. -- Colin Warwick Signal IntegrityProduct Marketing Manager,
> Agilent EEsof EDA blog http://signal-integrity.tm.agilent.com[2] -----Original Message----- From:
> si-list-bounce@freelists.org[3]
> [mailto:si-list-bounce@freelists.org[4]] On Behalf Of Powell, Jon N
> Sent: Tuesday, April 06, 2010 11:48 AM To: steve weir;
> si-list@freelists.org[5] Cc: bob@teraspeed.com[6]; ibis@eda.org[7];
> ibis-users@eda.org[8] Subject: [SI-LIST] Re: Straw poll and call for
> comments: Crowdsource IBIS model directory by use of a wiki such as
> wikipedia? Isn't there also a legal issue here? Who owns the IP or the
> copyright and who is going to be responsible for violation of said
> when a copy is kept in a database? Jon Powell EPSD Product SI 將
> -----OriginalMessage----- From: si-list-bounce@freelists.org[9]
> [mailto:si-list-bounce@freelists.org[10]] On Behalf Of steve weir Sent:
> Monday, April 05, 2010 6:58 PM To: si-list@freelists.org[11] Cc:
> bob@teraspeed.com[12]; ibis@eda.org[13]; ibis-users@eda.org[14] Subject:
> [SI-LIST] Re: Straw poll and call for comments: Crowdsource IBIS model
> directory by use of a wiki such as wikipedia? Colin, Hosting is so
> cheap as to be a non-issue. Setting up the database mechanics is not
> particularly difficult either. The real cost is in the administration.
> In my opinion this needs people willing to serve as librarians who
> will act as the gate keepers so that the site is not overrun with junk. Best Regards, Steve.
> colin_warwick@agilent.com[15] wrote: Hi, Thanks to everyone for the
> feedback and encouragement :-) There are several options each with
> pros and cons * Webpage with an appointed honorary librarian * Wikis
> e.g. hosted and self-hosted http://www.wikimatrix.org/[16] *
> Discussion forums (bulletin
> boards) e.g. hosted and self-hosted http://www.forummatrix.org/[17] *
> Email reflectors like the si-list http://freelists.org[18] * Shared
> document/table like a Google Docs spreadsheet.
> http://docs.google.com/[19] * Hybrids of the above like Google Wave
> http://wave.google.com[20] which they say is a "next generation"
> email/collaboration/documentation tool Here are some issues with
> each: * Ease-of-use versus functionality: email is easy to use, but
> email reflectors and forums have limited searchablity and it's hard to
> aggregate threads of (possibility duplicative) conversations. *
> WYSIWYG versus markup
> languages: some wikis and forums require you learn a mark up language.
> * "Onetruth" (conclusion) versus "Let a hundred flowers blossom"
> (conversation)(yes, I do understand the irony of Mao Zedong's imperative):
> **Wikis attempt to arrive at some sort of consensus between the
> editors on the readers' behalf (although there's usually a discussion
> page for editors behind the "real" page for readers) whereas **
> Discussion Forums let everyonevoice their own opinion and each reader
> has to plow through the threads to draw their own conclusion from the
> (possibly heated)
> conversation.* Reputation: How do you hold a contributor accountable
> for their contribution? How exclude spam in? * Privacy: How much info
> to do I have to submit to sign up? As a reader? As a writer? How to
> prevent harvesting of personal info by nefarious agents? *
> History/reversion: How do we track and undo "bad" edits? How to delete "bad" postings? * Who pays?
> There are plenty of "free" hosting sites, usually ad-funded. Do we
> want an adfree site by paying to self-hosting fee? If so, how do we split the check?
> * Structured versus unstructured: Do you want a rigorous database
> schema (specific column headings/fields for each row/record in
> (possibly
> interlinked) tables)? Or more free form? If structured, how to come to
> a consensus schema? * Who runs the thing? What are the costs and
> benefits for the admin? I added a second straw poll to the bottom of:
> http://signal-integrity.tm.agilent.com/2010/crowdsource-ibis-models
> -directory/[21] ...so you can vote for your favorite... Best regards,
> -- Colin Warwick Signal Integrity Product Manager, Agilent EEsof EDA
> -----Original Message----- From: si-list-bounce@freelists.org[22]
> [mailto:si-list-bounce@freelists.org[23]] On Behalf Of Howard Johnson Sent:
> Saturday, April 03, 2010 1:00 AM To: si-list@freelists.org[24] Subject:
> [SI-LIST] Re: Straw poll and call for comments: Crowdsource IBIS model
> directory by use of a wiki such as wikipedia? Hey Colin, I think you
> are on to a good idea. Individual users spend way too much time
> farting around trying to put together good IBIS models. Much of that effort seems wasted.
> I'd like to see the list include some sort of "user voting" feature so
> the readers of the list could see if other people found the model
> "useful". Some "wiki" type tools allow that kind of feedback and I
> believe it would be crucial, because I believe you will never get an
> official committee to vet the models -- it has to be done through
> independent user evaluations. Good luck, and keep plugging on this
> idea, it's a good one. Yes, I went to your link and voted. Best
> regards, Dr. Howard Johnson, Signal Consulting Inc.,
> tel+1 509-997-0505, howie03@sigcon.com[25] www.sigcon.com[26] --
> tel+High-Speed
> Digital Design seminars, publications and films -----Original
> Message-----
> From: si-list-bounce@freelists.org[27]
> [mailto:si-list-bounce@freelists.org[28]] On Behalf Of steve weir Sent:
> Friday, April 02, 2010 6:09 PM To: colin_warwick@agilent.com[29] Cc:
> si-list@freelists.org[30] Subject: [SI-LIST] Re: Straw poll and call
> for
> comments: Crowdsource IBIS model directory by use of a wiki such as
> wikipedia? My view on the usefulness of such a directory all depends
> on how well the directory would be maintained / policed and whether
> the directory would include information that would indicate the model's likely usefulness.
> There are a lot of IBIS ( HSPICE models as well for that matter ),
> that aren't particularly useful. Many have not been verified in any
> way. Some of them do not even parse. Anyway, if this is going to be
> undertaken, I would really like to see something similar to the way
> that the FPGA vendors list IPcores. Target Model Manufacturer Target
> Model Part Number Free or pay modelModel basis: Raw original model,
> SPICE derived model, Measurement based model IBIS version Passed
> parser or not w/ parser version Model verified or not Link to model,
> or model supplier Steve colin_warwick@agilent.com[31]
> wrote: Hi, Bottom line on top: Any interest in using and/or
> contributing to an IBIS model directory by use of a wiki such as
> wikipedia? Please vote in this informal straw poll:
> http://signal-integrity.tm.agilent.com/2010/crowdsource-ibis-models
> -director[32y/ ...and/or leave a comment there, and/or comment to this
> thread. Backstory: I posted the message below to the IBIS lists, but
> was disappointed that the response was fairly mute. So, I'm posting it
> here in the hope it will resonate with si-listers. (If you are also on
> the IBIS lists, this is a duplicate. Sorry!) Best regards, -- Colin
> Warwick Signal Integrity Product Manager, Agilent EEsof EDA
> -----Original Message----- From:WARWICK,COLIN Sent: Wednesday, March 31, 2010 11:59 AM To:
> IBIS-Interconnect; 'ibis-macro@freelists.org[33]' Subject: Straw poll
> and call for comments: Crowdsource IBIS model directory by use of a
> wiki such as wikipedia? Hi, I get several emails a month from
> customers asking "Is there an IBIS model for XYZ part from ABC IC vendor". I usually point them at:
> http://www.teraspeed.com/ibis_resources.html[34]
> http://www.eigroup.org/ibis/ibis%20table/models.htm[35] If the info is
> out-of-date (as is often the case), I ask them to do an advanced
> Google search like:
> http://www.google.com/advanced_search?q=IBIS+site:someicvendordomain.c
> [36] om(replace someicvendordomain.com with the IC vendor's domain,
> obviously) ButI'm wondering if there's a better way than "spray and
> pray" Googling or burdening a single librarian with hundreds of update
> requests. Sooo...How about crowdsourcing? "Crowd-what-ing," you say?
> Here's a definition from
> wikipedia: 'Crowdsourcing is a neologistic compound of Crowd and
> Outsourcing for the act of taking tasks traditionally performed by an
> employee or contractor, and outsourcing them to a group of people or
> community, through an "open call" to a large group of people (a crowd)
> asking for contributions.' (from
> http://en.wikipedia.org/wiki/Crowdsourcing[37] ) Specifically, I'm
> wondering if we should create a table off of the main IBIS page on wikipedia:
> http://en.wikipedia.org/wiki/Input_Output_Buffer_Information_Specifica
> [38] tion ...(or some other wiki) for IC vendors to update their info
> themselves.
> It would look something like this prototype I cobbled together:
> http://en.wikipedia.org/wiki/User:Woz2/Input_Output_Buffer_Information
> [39] _Specification/Table_of_IBIS_models Thoughts? Please vote in this
> informal straw poll:
> http://signal-integrity.tm.agilent.com/2010/crowdsource-ibis-models-di
> [40] rectory/ and/or leave a comment there, and/or comment to this
> thread. Best regards, -- Colin Warwick Signal Integrity Product
> Manager, Agilent EEsof EDA
>
>
> --- Links ---
> 1 mailto:colin_warwick@agilent.com
> 2 http://signal-integrity.tm.agilent.com
> 3 mailto:si-list-bounce@freelists.org
> 4 mailto:si-list-bounce@freelists.org
> 5 mailto:si-list@freelists.org
> 6 mailto:bob@teraspeed.com
> 7 mailto:ibis@eda.org
> 8 mailto:ibis-users@eda.org
> 9 mailto:si-list-bounce@freelists.org
> 10 mailto:si-list-bounce@freelists.org
> 11 mailto:si-list@freelists.org
> 12 mailto:bob@teraspeed.com
> 13 mailto:ibis@eda.org
> 14 mailto:ibis-users@eda.org
> 15 mailto:colin_warwick@agilent.com
> 16 http://www.wikimatrix.org/
> 17 http://www.forummatrix.org/
> 18 http://freelists.org
> 19 http://docs.google.com/
> 20 http://wave.google.com
> 21 http://signal-integrity.tm.agilent.com/2010/crowdsource-ibis-models-directory/
> 22 mailto:si-list-bounce@freelists.org
> 23 mailto:si-list-bounce@freelists.org
> 24 mailto:si-list@freelists.org
> 25 mailto:howie03@sigcon.com
> 26 http://www.sigcon.com
> 27 mailto:si-list-bounce@freelists.org
> 28 mailto:si-list-bounce@freelists.org
> 29 mailto:colin_warwick@agilent.com
> 30 mailto:si-list@freelists.org
> 31 mailto:colin_warwick@agilent.com
> 32 http://signal-integrity.tm.agilent.com/2010/crowdsource-ibis-models-director
> 33 mailto:ibis-macro@freelists.org
> 34 http://www.teraspeed.com/ibis_resources.html
> 35 http://www.eigroup.org/ibis/ibis%20table/models.htm
> 36 http://www.google.com/advanced_search?q=IBIS+site:someicvendordomain.c
> 37 http://en.wikipedia.org/wiki/Crowdsourcing
> 38 http://en.wikipedia.org/wiki/Input_Output_Buffer_Information_Specifica
> 39 http://en.wikipedia.org/wiki/User:Woz2/Input_Output_Buffer_Information
> 40
> http://signal-integrity.tm.agilent.com/2010/crowdsource-ibis-models-di
> ------------------------------------------------------------------
> To unsubscribe from si-list:
> si-list-request@freelists.org with 'unsubscribe' in the Subject field
>
> or to administer your membership from a web page, go to:
> http://www.freelists.org/webpage/si-list
>
> For help:
> si-list-request@freelists.org with 'help' in the Subject field
>
>
> List technical documents are available at:
> http://www.si-list.net
>
> List archives are viewable at:
> http://www.freelists.org/archives/si-list
>
> Old (prior to June 6, 2001) list archives are viewable at:
> http://www.qsl.net/wb6tpu
>
>
>
>
-- Steve Weir IPBLOX, LLC 150 N. Center St. #211 Reno, NV 89501 www.ipblox.com (775) 299-4236 Business (866) 675-4630 Toll-free (707) 780-1951 Fax ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@freelists.org with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: http://www.freelists.org/webpage/si-list For help: si-list-request@freelists.org with 'help' in the Subject field List technical documents are available at: http://www.si-list.net List archives are viewable at: http://www.freelists.org/archives/si-list Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. -------------------------------------------------------------------- |For help or to subscribe/unsubscribe, e-mail majordomo@eda-stds.org |with the appropriate command message(s) in the body: | | help | subscribe ibis <optional e-mail address, if different> | subscribe ibis-users <optional e-mail address, if different> | unsubscribe ibis <optional e-mail address, if different> | unsubscribe ibis-users <optional e-mail address, if different> | |or e-mail a request to ibis-request@eda-stds.org. | |IBIS reflector archives exist under: | | http://www.eda-stds.org/pub/ibis/email_archive/ Recent | http://www.eda-stds.org/pub/ibis/users_archive/ Recent | http://www.eda-stds.org/pub/ibis/email/ E-mail since 1993 -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. -------------------------------------------------------------------- |For help or to subscribe/unsubscribe, e-mail majordomo@eda-stds.org |with the appropriate command message(s) in the body: | | help | subscribe ibis <optional e-mail address, if different> | subscribe ibis-users <optional e-mail address, if different> | unsubscribe ibis <optional e-mail address, if different> | unsubscribe ibis-users <optional e-mail address, if different> | |or e-mail a request to ibis-request@eda-stds.org. | |IBIS reflector archives exist under: | | http://www.eda-stds.org/pub/ibis/email_archive/ Recent | http://www.eda-stds.org/pub/ibis/users_archive/ Recent | http://www.eda-stds.org/pub/ibis/email/ E-mail since 1993 -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. -------------------------------------------------------------------- |For help or to subscribe/unsubscribe, e-mail majordomo@eda-stds.org |with the appropriate command message(s) in the body: | | help | subscribe ibis <optional e-mail address, if different> | subscribe ibis-users <optional e-mail address, if different> | unsubscribe ibis <optional e-mail address, if different> | unsubscribe ibis-users <optional e-mail address, if different> | |or e-mail a request to ibis-request@eda-stds.org. | |IBIS reflector archives exist under: | | http://www.eda-stds.org/pub/ibis/email_archive/ Recent | http://www.eda-stds.org/pub/ibis/users_archive/ Recent | http://www.eda-stds.org/pub/ibis/email/ E-mail since 1993 -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. -------------------------------------------------------------------- |For help or to subscribe/unsubscribe, e-mail majordomo@eda-stds.org |with the appropriate command message(s) in the body: | | help | subscribe ibis <optional e-mail address, if different> | subscribe ibis-users <optional e-mail address, if different> | unsubscribe ibis <optional e-mail address, if different> | unsubscribe ibis-users <optional e-mail address, if different> | |or e-mail a request to ibis-request@eda-stds.org. | |IBIS reflector archives exist under: | | http://www.eda-stds.org/pub/ibis/email_archive/ Recent | http://www.eda-stds.org/pub/ibis/users_archive/ Recent | http://www.eda-stds.org/pub/ibis/email/ E-mail since 1993Received on Thu Apr 8 09:46:27 2010
This archive was generated by hypermail 2.1.8 : Thu Apr 08 2010 - 09:46:52 PDT