Re: Pspice compatibility: Bus representation in subcircuit calls

Jim,

> >But it has nothing to do with lvs.  You
> >still confuse schematic caputure capabilities
> >with SPICE and lvs.  The netlister interfaces
> >between these.  The problem is that the computer
> >CAD tools don't allow things to be drafted and
> >now people got used to the artificial limit.
> >
>
> We still seem to be running in circles.  In my mind schematic capture
> must be able to do the following things:
>
> (1) Create a netlist readable without ambiguity by the Spice engine.
> (2) Yet present a useful visual representation of the circuit...
> humanly readable; AND handle hierarchical and bussed designs.
> (3) Have a user-friendly GUI to make drawing convenient.
> (4) Allow placing "markers" on the schematic that then show waveforms
> in an appropriate viewer.
> (5) Show operating point data (voltages and currents) directly on the
> schematic, for debugging, if desired.
> (6) Be able to produce LVS netlists in formats readable by many layout
> tools.
>
> PSpice Schematics can do *all* of the above ;-)

That is a good list.  I certainly hope I never
implied anything in contradiction to it.  My own
focus was on it "(1) Creating a netlist readable
without ambiguity by the Spice engine", and then
differentiating that from the SPICE engine itself.

I realize that I throughly pissed Larry off.  What
it is.  But, I don't think Larry has justification
to get excited after he makes false claims about
LTspice from wrong conclusions about what
schematic capture is used in house.  The Snynario
netlister does not meet your list requirements and
we don't use it.  I thought it was pretty stupid to
draw conclusions about what LTspice can do from a
netlister that is only used with LTspice by Larry
to the best of my knowledge.  In general, I don't
see an excuse for a netlister not to be able to
make correct syntax netlists for different SPICE
programs and LVS either; and I specifically don't
see an excuse for drawing conclusions about
different tools from using a netlister that isn't
intended to work with them.

Larry's used LTspice as his simulator for IC
design and I've even helped him in the past with
generating correct hspice syntax so that he could
run TSMC(I think they were) libraries in LTspice.
Now he wants to invoke the psychology of the
customer being always right when he is not a
customer in the remotest interpretation.  And
he's difficult to work with because he doesn't even
have hspice to try out the stuff I suggest so he
can see what's really what in the intermediate
syntax.  While I don't much care what fabless IC
design concerns do with LTspice, I do find it
disingenuous to post stupid assumptions based on
a lame netlister in response to someone answering
his questions with a clear concise example that
illustrates the thing he needs to know to solve
his problem.

--Mike