Re: Minutes, IBIS Teleconference Meeting 7/20

For the message bellow,
" Even though the model is non-monotonic, it may represent real data"
" (3) ignore this problem and force the user to modify the IBIS file."
" Bob suggested that we work on (1) as a low priority activity. If the fix is too difficult, then we might consider (3). No one wanted (2). "

I want to ask:
It seems that a good model maybe is non-monotonic(right or wrong ?),Then how can we modefy the IBIS file ?

Thanks,
regards,
LiuWeidong

----- Original Message ----- >
>
> IBISCHK3 BUG TRACKING
> - BUG57 Non-Mononic Table Causes Waveform Endpoint Test to Fail
> Bob Ross introduced BUG57 by pointing out that if the [Pulldown] and/or
> the [Pullup] table contains non-monotonic data in the clamping regions,
> and
> there are no [Gnd Clamp] or [Power Clamp] tables, ibischk3 gives an
> incorrect Error message.
>
> The non-monotonic data itself causes ibischk3 to calculate the wrong
> endpoint values because the algorithm probably has numerical difficulties.
> It probably starts its convergence calculation at one end of the table
> rather than from the middle and gets numerically confused with the
> non-monotonic data.
>
> Even though the model is non-monotonic, it may represent real data. Some
> EDA tools will correctly process the model. However, the recently
> implemented Waveform endpoint tests now report an Error instead of a
> Warning, preventing the model to be processed in systems that uses
> ibischk3
> for input model parsing.
>
> Bob suggested classifying BUG57 as Annoying, Low, and Open.
>
> The problem is how to resolve BUG57. The choices are (1) fix the test,
> (2)
> change the Error back to a Warning, or (3) ignore this problem and force
> the
> user to modify the IBIS file.
>
> Bob suggested that we work on (1) as a low priority activity. If the fix
> is
> too difficult, then we might consider (3). No one wanted (2). Stephen
> Peters suggested that a note could be added to the Warning or Error
> message
> to alert the user of a possible reason for the Error Message so that the
> user could modify the model. Bob suggested that because this is a low
> priority bug, it should be investigated after all the other open bugs are
> fixed. Then we can decide how to proceed.
>
>

 
Received on Tue Jul 24 18:11:38 2001