Todd, Currently, all IBIS models generated here are done so with SPICE to IBI= S translation, and the resulting model is then simulated in HSPICE as a B-Element, across frequency with the recommended datasheet load. These= waveforms are correlated to the source HSPICE model of the device. Since you and I are both members of the recently created IBIS Qualifica= tion Committee, we both share a desire to improve the quality of IBIS models= being created, and to institute IBIS model qualification methods to ens= ure their accuracy. I for one advocate the qualification of s2i generated models through SPICE simulation. We are eager to learn and institute w= hat qualification methods are needed. We have a very large library of IBIS models created over a period of ma= ny years. I am not stating that among these thousands of models there doe= s not exist any errors, but any error discovered will be immediately addressed and corrected, as some of the members of the SI list are awar= e of through experience. We are open minded and committed to improvement. Regards, Adam "Todd Westerhoff" <twester@xxxxxxxxxxx>@freelists.org on 03/25/2002 06:28:08 PM Please respond to twester@xxxxxxxxxxx Sent by: si-list-bounce@xxxxxxxxxxxxx To: <si-list@xxxxxxxxxxxxx> cc: Subject: [SI-LIST] Re: IBIS Model Quality (or lack thereof) Oh no, here we go ... For the record, we've had *VERY* good luck getting HSpice to correlate = with IBIS simulations - the problem is, we've had to create most of the IBIS= models ourselves ir order to get things to match. Please, let's save the "ultimate HSpice accuracy" arguments for another= thread (preferably one that gets redirected to /dev/null). I'm well aw= are of IBIS' limitations, and we've done lots of real-world comparisons for= our current applications. IBIS will work just fine if we have decent model= s ... AND, I'll be able to do all the post-route analysis I want. The question remains, folks ... what semiconductor vendors are willing = to "step up the plate" and tell us how they test their IBIS models to ensu= re correlation to a known source (measurement or HSpice)? Inquiring minds want to know! Todd ;-) Todd Westerhoff Signal Integrity Engineer Hammerhead Networks 5 Federal Street - Billerica, MA - 01821 email:twester@xxxxxxxxxxx - ph: 978-671-5084 =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D "I'm starting With the man in the mirror I'm asking him to change his ways And no message could have been any clearer If you wanna make the world a better place Take a look at yourself, and then make a change" - "Man in the Mirror", Michael Jackson -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx]On Behalf Of Chris Cheng Sent: Monday, March 25, 2002 5:18 PM To: si-list@xxxxxxxxxxxxx Subject: [SI-LIST] Re: IBIS Model Quality (or lack thereof) Why use IBIS at all ? If you are convinced that IBIS is not good enough (which I am), don't simulate and just follow whatever the vendors design rules say. After =3D= all, if you deviate from the rules based on your incorrect IBIS models, do =3D= you think the vendor will really take responsibility if it doesn't work ? =3D= If you follow the design rules, what value does the simulation add to you =3D design ? If you are serious enough to simulate, you must be working on something= =3D that is unique about your own system that needs to be custom optimized =3D beyond what the component guideline can tell you. Get the SPICE model and do a= =3D good job of modeling your own system. If a small little start up like mine =3D= can get SPICE model from vendors, anyone can. Its just a matter of a few =3D= NDA and extra effort. -----Original Message----- From: Todd Westerhoff [mailto:twester@xxxxxxxxxxx] Sent: Monday, March 25, 2002 12:59 PM To: si-list@xxxxxxxxxxxxx Subject: [SI-LIST] IBIS Model Quality (or lack thereof) Hi all, We have been doing a lot of comparisons between IBIS and HSpice models lately, with a lot of less-than-satisfactory results. I have an open question for the semiconductor suppliers among us: What testing is performed after an IBIS model is created, to ensure =3D= that the completed model behaves as expected? I'm interested in responses from vendors that actually SIMULATE the IBIS model before distributing it =3D= for customer use. It looks to me as though many of the models I've =3D received were never used in a simulation before being released ... and, as a potential customer, I find that quite disheartening. So the question is - what processes are being used to test IBIS models = =3D and ensure they function properly before their release to customers? As always, replies both on and off the list are greatly appreciated. Todd. Todd Westerhoff Signal Integrity Engineer Hammerhead Networks 5 Federal Street - Billerica, MA - 01821 email:twester@xxxxxxxxxxx - ph: 978-671-5084 =3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D= 3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D =3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D3D=3D= 3D=3D3D=3D3D=3D3D=3D3D=3D3D "I=3D92m starting With the man in the mirror I=3D92m asking him to change his ways And no message could have been any clearer If you wanna make the world a better place Take a look at yourself, and then make a change" - "Man in the Mirror", Michael Jackson ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List archives are viewable at: =3D20 //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages=3D20 Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu =3D20 ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu = ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu