Re: Ibis standard for feedback

Hello Sergey:

Based on your description, I believe your question
may relate to some dynamic impedance control buffers.

IBIS Version 3.2 partially supports feedback through
the "Bus_hold" submodel where another buffer can be
switched in parallel based on a trigger voltage to increase
the overall buffer strength.

Because of some polarity considerations, this method
may need to be completed for "Reduced_strength"
operation based on a trigger voltage. I plan to author
a BIRD for this improvement for a pending IBIS
Version 4.0.

As previously stated, I also believe that such
operation could be described in the pending IBIS-X
macro language.

Bob
Mentor Graphics

> Sergey Sofer wrote:
>
> Hello Bob,
>
> The method specified by Yoked is a kind of model selecting
> method, where the control for driving strong or less strong,
> comes from pad itself as specific voltage level.
>
> We saw that there is an option to take care on IO buffer with
> different driving models connected in parallel, with "model
> selector" in the last version of IBIS (3.2).
>
> The Yoked's question may be asked in other words:
> Is there any possibility to select models by pad's voltage level?
>
> Regards,
> Sergey.
 
Received on Mon Jul 9 06:54:45 2001