Raghavendra: In standard IBIS models (without the language extensions), I prefer to stub off analog pins with terminator models (Model_type Terminator). The terminators can just be a capacitor (C_comp) or some other load to approximate the actual impedance, if known. Analog functions are not defined in IBIS models. So stubbing off the analog pins just passively completes the net for any trace attached to the analog pin. When you use terminators for analog functions, it is helpful to document this in the [Notes] section. Some people might use NC for analog pins, but I prefer to reserve NC for true no-connects where the pin is defined, but there is no connection to the die. Bob Raghavendra M wrote: > Hi, > I have an analog pin like analog output of DAC or Vcontrol pin of the PLL. > How should i model this an analog pin. Does ibis specify a standard to > model an analog pin? > How should i specify about this pin in ibis file? > > Regards > Raghavendra > -- Bob Ross Teraspeed Consulting Group LLC Teraspeed Labs 121 North River Drive 13610 SW Harness Lane Narragansett, RI 02882 Beaverton, OR 97008 401-284-1827 503-430-1065 http://www.teraspeed.com 503-246-8048 Direct bob@teraspeed.com Teraspeed is a registered service mark of Teraspeed Consulting Group LLC -- 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 Mon Jul 13 21:07:26 2009
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