Subject: RE: [IBIS-Users] On IBIS Model Generation
From: S Jairam (sjairam@ti.com)
Date: Tue Sep 17 2002 - 02:45:58 PDT
Prabhu / Eckhard
Thanks for your responses. This makes it clear. So, the assumption
that the buffers sees a proper termination, needs to be adhered.
Regards,
Jairam.
Mohan, Prabhu writes:
#Hi Jairam,
#
#You are correct. The buffers characteristics will vary with load.
#Since there is no real way to know what load the buffer will be driving
#and fast edge rates make traces look like 50ohm transmission lines,
#most models use 50ohm pullup and pulldown to derive the VT curves.
#
#At this point I think it is upto the simulator vendor to come up
#with the appropriate algorithm to extract buffer characteristics
#for other loads.
#
#Hope that was of some help.
#
#Prabhu/~
#
#-----Original Message-----
#From: S Jairam [mailto:sjairam@ti.com]
#Sent: Monday, September 16, 2002 11:48 PM
#To: Mohan, Prabhu
#Cc: ibis-users@eda.org
#Subject: RE: [IBIS-Users] On IBIS Model Generation
#
#
#
#Hi Prabhu,
#
#Thanks for the answer. However the flavour of the question still
#remains the same. The buffer drive will depend on the load (might not
#just be the package load) that will be hooked up. Should not this
#again be varied for generating the IBIS model ?
#
#Thanks and Regards,
#Jairam.
#
#
#Mohan, Prabhu writes:
##Hi Jairam,
##
##The package parameters (RLC) are NOT taken into account while generating
#the
##IBIS model. They are to be provided seperately to facilitate simulation
##using other (SI) tools.
##
##Ragards
##Prabhu/~
##
##-----Original Message-----
##From: S Jairam [mailto:sjairam@ti.com]
##Sent: Monday, September 16, 2002 10:07 PM
##To: ibis-users@eda.org
##Subject: [IBIS-Users] On IBIS Model Generation
##
##
##
##Hi,
##
## This might sound very dumb a question, but I dont have an
##answer to this.
##
## When IBIS model generation for an IO buffer is in progress,
##only one package load (a set of RLC parameters) is used to calculate
##all the IV curves. Is that valid ? Because in such a case the
##I-V curves of buffer would then be dependent of the package load.
##
## Shouldn't it be that the calculation be done for various load
##points with each load-point providing a set of I-V curves.
##
##Please correct me if I am wrong.
##
##Thanks and Regards,
##Jairam.
##--
-- # S.Jairam, # Texas Instruments Bangalore, # E-Mail: sjairam@ti.com # Phone : 080 5099 689 |------------------------------------------------------------------ |For help or to subscribe/unsubscribe, email majordomo@eda.org |with just 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 email a written request to ibis-request@eda.org. | |IBIS reflector archives exist under: | | http://www.eda.org/pub/ibis/email_archive/ Recent | http://www.eda.org/pub/ibis/users_archive/ Recent | http://www.eda.org/pub/ibis/email/ E-mail since 1993
This archive was generated by hypermail 2b28 : Tue Sep 17 2002 - 03:02:47 PDT