RE: Problem with clocked driver

Arpad,

Thanks for your response.

Could you please give me an example of an HSPICE netlist that implements the
technique you suggested? That is, the technique of performing the DC sweep
after clocking the buffer.

The idea of using initial conditions doesn't work in this case as I do not
have access to the internal nodes because this model is encrypted.

Thanks.

Regards.

Hassan.

-----Original Message-----
From: Muranyi, Arpad [mailto:arpad.muranyi@intel.com]
Sent: Friday, September 01, 2000 11:04 AM
To: Ali, Hassan [KAN:0G15:EXCH]; ibis
Subject: RE: Problem with clocked driver

Ali,

This buffer seems to have flip/flop in it which doesn't seem to get
initialized correctly at t=0 and both its pullup and pulldown drivers
seem to be on at t=0. This could be fixed if you could initialize
some of the internal nodes for t=0 using the .IC statement. However,
you can ignore this and just clock the buffer a few times before you
begin the actual sweep to get the IV curves.

So, to get a pulldown IV curve, I would set the input low, wiggle the
clock and then sweep the IV curve. To get a pullup IV curve, I would
set the input high, wiggle the clock and then sweep the IV curve.

Arpad Muranyi
Intel Corporation
=====================================================================

-----Original Message-----
From: Hassan Ali [mailto:hali@nortelnetworks.com]
Sent: Thursday, August 31, 2000 11:18 AM
To: ibis
Subject: Problem with clocked driver

I'm trying to create an IBIS model of a differential driver from its
encrypted HSPICE model. The driver operates with the P and N outputs each
terminated with 50 ohm to VDD (=1.8V). This driver has a couple of unusual
characteristics:

- transient simulation shows that at time=0 the driver output is around
950mV regardless of the input stimulus voltage.
- the driver has a clock input as one of the driver subcircuit parameters.
The driver output follows the driver input stimulus only upon receiving a
rising clock edge.

Does anybody know how I should go about creating the IBIS model of this
driver (say using s2ibis2 program)?

Thanks.

Hassan.

 
Received on Fri Sep 1 09:06:10 2000