Hi Nam, Arpad has explained this in a lecture on IBIS. The lecture slide can be found at http://download.intel.com/education/highered/signal/ELCT762/Class17_18_I BIS_io_buffer_class.ppt <http://download.intel.com/education/highered/signal/ELCT762/Class17_18_ IBIS_io_buffer_class.ppt> Slide-24 in this lecture explain, why 4-VT tables? Hope, this presentation will help you. Thank you, Muniswar ________________________________ From: owner-ibis@eda.org [mailto:owner-ibis@eda.org] On Behalf Of Nguyen, Duynam Sent: Friday, May 02, 2008 12:48 AM To: ibis@eda.org Subject: [IBIS] Extracting V-T waveform data for the purpose of modeling a CMOS buffer In section 3.2 of the 09/15/05 "IBIS MODELING COOKBOOK For IBIS Version 4.0" document, it is stated, "... for each simulation corner, four V-T data sets are generally recommended. Two waveforms - either featuring a load to ground or a relatively low voltage - are generated for the buffer output switching low to high. The other two waveforms - both featuring a load to Vcc or a relatively high voltage - are generated for the buffer output switching high to low." Why do we need two waveforms for each buffer output transition ? Thanks, Nam -- 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 Thu May 1 21:30:13 2008
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