Re: Bird38

Bob,

I agree that any specification enhancement should be simple and
consistent.

A very simplified version of bird 38, which would satisfy most
needs would give an entries similar to the following:

example a:
[Over/undershoot]
|Time Max_overshoot Max_undershoot
 0 0.5 -0.5

example b:

[Over/undershoot]
|Time Max_overshoot Max_undershoot
 20ns 2.0 -2.0
 20.1ns 0.5 0.5

Example a) would cover the case where the dynamic and static overshoots
and undershoots are the same as the dynamic values.

Example b) shows much more realistic and useful values. The
dynamic overshoot is 2.0V above Vcc. This is the value that might
be transferred into a RAIL file.

I'm not familiar enough with IBIS to understand what you mean by:
 - "existing conventions" (what is wrong with tables?)
 - "technologies" (simulator technology or semiconductor technology?)
 - "meaningful for all columns"

Talk to you later,
John

Bob said:
> My preference is that any enhancement be simple. While some of the
> proposals involve tables, I suspect that the practical reality is
> that (1) there is too much data for anyone to really specify, and
> (2) very few vendors will consider processing that specific
> enhancement.
> Also, I favor consistency with the existing conventions
> and structure rather than adding very specific, special
> purpose,"warts".
> By this, any extension needs to work with all of the technologies and
> be meaningful for all of the columns.
>

-- 
John Fitzpatrick   <John.Fitzpatrick@ln.cit.alcatel.fr>    
Alcatel CIT, 4 rue de Broglie, 22304 Lannion, France
Tel: (+33)96.04.79.33  Fax: (+33)96.04.85.09