Re: @above in analyses other than tran and dc sweep

David Smith wrote:
> 
> Having one DC solution have a dependency on a different DC solution within a DC sweep seems like a bad idea to me and not consistent with the traditional definition of a DC sweep.

As mentioned before, there are circuits that have multiple
dc solutions, in particular hysteresis, so you can't say
"the" dc solution.  People do design these circuits
intentionally!

> If it means that an event is generated going from one DC solution in a DC sweep to another then a rational would be helpful to understand the need.

There is an example in the LRM of a sample and hold
that uses above to get the correct time=0 solution
when the smpl pin is initially high, but this doesn't
need an event during a dc sweep.

Not in the LRM, but in a discussion document from the
subcommittee when we added above, was a discussion about
not giving repetitive warning messages.  For example

   @above( BV - V(a,c))
     $strobe("Diode is breaking down.");

Clearly, if one does
   if( BV - V(a,c) < 0)
     $strobe("Diode is breaking down.");
then one could get this message for dozens or hundreds of
points in a dc sweep, which could be quite messy, and doesn't
give any new information.

-Geoffrey

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