Re: multiple analog blocks

Kevin -
There are a few problems with @initial_step:

1) it's a *bad* idea to use it for a dc sweep -- if you put the
temperature-update equations in there (setting aside self-heating,
the "ambient" temperature is used to set internal variables which
are constant for a transient analysis) then these variables are
not updated when sweeping temperature

2) an analog solver has to run the @initial_step block on every
iteration of the first step of a transient analysis

On the other hand, the compiler can -- and thus should -- determine
which variables depend only on the parameters (and perhaps
temperature -- and the compiler/simulator will also know when
temperature is fixed or not).  It can do this simply by analyzing
the dependency tree.  It does not need any further assistance
from the model writer.

-Geoffrey


Kevin Cameron wrote:
> 
> Seems to me that it would be good to give the simulator the opportunity
> to evaluate internal variables from parameters post-elaboration and
> prior to actual transient simulation (if they are going to be constant
> for transient). If @initial_step doesn't do that (and it doesn't seem
> to), can we make it that digital initial blocks run before any analog
> processes starts, so that a "smart" compiler can work out what will be
> constant?
> 
> Kev.