RE: [SI-LIST] : Problem in IBIS simulation

About this list Date view Thread view Subject view Author view

From: Gutzmann, Michael (michael.gutzmann@intel.com)
Date: Fri Apr 20 2001 - 09:15:17 PDT


Rajesh,

(a) IBIS does not provide information on how a signal that reaches an input
buffer will be propagated through the input buffer circuit to its output,
but gives you numbers for the upper and lower boundary of the input
switching threshold (vinl, vinh) and if the input is inverting/noninverting.
HSPICE takes those parameters and sets the input buffer output to either 0V
representing LOW level or 1V representing HIGH level symbolically.
So when your input buffer output jumpes from 0v to 1v and vice versa it just
indicates that the input thresholds have been passed.

(b) Probably just a simulator issue. It's just not allowed to leave a buffer
terminal open, because if you enable the same I/O buffer using it as output
it would be a real error. Solution: Tie a DC voltage source (either LOW or
HIGH) to the output buffer input and it should work.

Michael

-----Original Message-----
From: rajesh.kaushik@st.com [mailto:rajesh.kaushik@st.com]
Sent: Friday, April 20, 2001 5:25 AM
To: si-list@silab.eng.sun.com
Subject: [SI-LIST] : Problem in IBIS simulation

Hello,
I am simulating an ibis file using HSPICE. I will be thankful to you if
anyone of you can help me in the following queries:

(a) While simulating an ibis buffer model of I/O type in the input mode,
i.e. when the signal from external world appears on the pad, the high
level output of input buffer is always 1V regardless of any other factor.
Why is it so ?

(b) Why if while using the I/O buffer in input mode I have to specify the
input for the output buffer, which is of no use to me, otherwise it gives
an error that no voltage sources are defined.

Thank you in anticipation
Regards
Rajesh Kaushik

**** To unsubscribe from si-list or si-list-digest: send e-mail to
majordomo@silab.eng.sun.com. In the BODY of message put: UNSUBSCRIBE
si-list or UNSUBSCRIBE si-list-digest, for more help, put HELP.
si-list archives are accessible at http://www.qsl.net/wb6tpu
****

**** To unsubscribe from si-list or si-list-digest: send e-mail to
majordomo@silab.eng.sun.com. In the BODY of message put: UNSUBSCRIBE
si-list or UNSUBSCRIBE si-list-digest, for more help, put HELP.
si-list archives are accessible at http://www.qsl.net/wb6tpu
****


About this list Date view Thread view Subject view Author view

This archive was generated by hypermail 2b29 : Thu Jun 21 2001 - 10:11:41 PDT