Re: different rising and falling Ramp dV

On Thu, 22 Mar 2001, Mike LaBonte wrote:
> Many IBIS models have different values for dV in the dV/dt_r and
> dV/dt_f. The clipping below from IBIS spec shows an example. But
> the usage rules imply that dV must be 60% of the voltage swing. If
> the voltage swing is measured between the 2 steady-state voltages,
> then how could you have different values for rise and fall dV? If
> there is variation in how simulators handle the Ramp dV values,
> then this may matter.

There is definitely variation in how simulators handle it. I am
aware of some that look only at dt, assuming the changes in load
change the voltages, and it really is 20% to 80%. I am aware of
others that look only at the quotient, assuming that the 20% and 80%
are only suggestions, and the modeler specified what was actually
tested. I have seen other variations, too.

 
Received on Fri Mar 23 01:02:34 2001