Re: Open drain model

Olli:

Open drain models require correct dV/dt_r values. A newer
version of is planned to issue an error if zero or negative
values are included for Ramp entries. The way you get
rising transition values is to terminate the output with
50 ohms (or the specified R_load value) to Vcc and record
the transition values for the low to high output transition.

Bob Ross
Mentor Graphics

Olli Timonen wrote:
>
> Hi,
>
> How should be the [Ramp] risetime dV/dt_r defined for an open drain
> model because pad cell cannot produce a rise transition? I turned into a
> model with open drain model and the rise time was defined as zero.
> ibischk3 says it's OK but the parser of Interconnect Synthesis (ICX)
> doesn't accept it.
>
> regards,
> Olli
 
Received on Thu Nov 9 10:20:58 2000