Timmy. Regarding the second question, I can not see the the purpose in specifing [Test Load] without the [Test Data], The test data or Golden Waveform is as I see it intended as a means of validating the model in your simulator. The [Test Load] is specifying under which load the [Test Data] was created. So if you run the model with the same load in the used simulator it should give you the waveform(s) described in the test data section, the golden waveform which is considered to be the "right answer". You say that you do not get a warning for this ? I suppose you are talking of the ibis parser not giving a warning if you specify [Test Load] without [Test Data] ? If it does not it probably should, but most from the point that it does not make much sense to specify [Test Load] without [Test Data] I would not expect it to give problems if nobody is trying to validate the model using the golden waveform, Actually I have never seen a model including a Golden Waveform so far. Which is a pity since it would help the user in his model validation a lot. /Anders ________________________________ From: owner-ibis-users@server.eda.org [mailto:owner-ibis-users@server.eda.org] On Behalf Of Muranyi, Arpad Sent: den 3 oktober 2007 17:34 To: Server EDA Subject: RE: [IBIS-Users] [Submodel] and [Add Submodel] keywords Timmy, 1) The submodel keywords were not "invented" for the purpose of reducing file size. Their purpose was to model specific behaviors of specific circuit types. The dynamic clamp, for example, is a special circuit in the buffer which moves the origin of the I-V curve in to clamp stronger when there is a transition in the waveform to "catch" overshooting and clamp them better. The bus hold is a similar special circuitry to implement some sort of a dynamic termination while reducing DC current consumption during long series of ones or zeroes on the line. While there may be other legitimate uses, be careful about all of the details to "get it right". Also beware that not all EDA vendors may support all variants of these keywords... 2) I am not sure how to answer this question at this point, and I don't have the time to research it, so I will let someone else answer it... Arpad ================================================================ ________________________________ From: owner-ibis-users@server.eda.org [mailto:owner-ibis-users@server.eda.org] On Behalf Of Ibis Model Sent: Wednesday, October 03, 2007 2:19 AM To: Server EDA Subject: [IBIS-Users] [Submodel] and [Add Submodel] keywords Hi forum posters, I tried to find the previous threads on [Submodel] and [Add Submodel] keywords to no avail, so here I'm posting yet another question. I understand that I have been posting questions a lot lately, so bear with me if anyone is getting bored with me spamming the forum. I have another two questions: 1. I find the [Submodel] and [Add Submodel] keywords very useful in shrinking the IBIS models file size. Assuming an IBIS models file containing 100 models and all sharing the same [Ground Clamp] and [Power Clamp] data. In this case, I can reduce the file size by using the keyword [Add Submodel] to refer to a [Submodel] that contains these [GND Clamp] and [POWER Clamp] data, thus avoiding to repeat the [GND Clamp] and [Power Clamp] data for each model for 100 times. While I manage to reduce the file size of the IBIS models by ~20%, is this technically the correct usage of the keywords? What does it exactly mean by a "Dynamic_clamp Submodel"? 2. I understand from the IBIS spec that the keyword [Test Load] was used to derive the golden waveform. Will there be a problem if define the [Test Load] keyword with the respective electrical parameters such as Rs_near, Vterm, Rp1_near on my driver without defining the [Test Data] keyword as well as not having a golden waveform for that IBIS model. This doesn't prompt me any warning when I perform the syntax check but I'm worried that this could be technically wrong as well. Please advice. Regards, Timmy ________________________________ Be a better Heartthrob. Get better relationship answers <http://us.rd.yahoo.com/evt=48255/*http://answers.yahoo.com/dir/_ylc=X3o DMTI5MGx2aThyBF9TAzIxMTU1MDAzNTIEX3MDMzk2NTQ1MTAzBHNlYwNCQUJwaWxsYXJfTkl fMzYwBHNsawNQcm9kdWN0X3F1ZXN0aW9uX3BhZ2U-?link=list&sid=396545433> from someone who knows. Yahoo! Answers - Check it out. -- This message has been scanned for viruses and dangerous content by MailScanner <http://www.mailscanner.info/> , and is believed to be clean. -- This message has been scanned for viruses and dangerous content by MailScanner <http://www.mailscanner.info/> , and is believed to be clean. -- 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 Wed Oct 3 09:26:19 2007
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