I'm trying to simulate my first nontrivial circuit with ngspice. The circuit in question is a discrete MOSFET driver. I wasn't able to find any spice models for the power MOSFETs I'm using (Ixys IXTP200N055T2), but I was able to find something from Fairchild for a similar device, FDP032N08.
The trouble (besides not being experienced with spice) I'm having is that the model from Fairchild is actually a subcircuit, and I'm not entirely sure how to structure my schematic such that gnetlist will make the right output. I'm running it as "gnetlist -g spice-sdb hbridge.sch" Best I can tell, as long as the refdes attribute starts with "Q" then it will be netlisted as Qfoo, which means spice won't be expecting a subcircuit. I think (although I'm having a hard time finding the right manual to read) that the identifier in the spice input must start with X to reference a subcircuit. I thought maybe I could change the refdes to start with X in the schematic (although I'd rather keep it as Q), but then the netlister outputs "QXfoo". I'm thinking this is because my symbol has an attribute device=NMOS_TRANSISTOR. So, I'm left with a couple broad questions: - Is there some combination of attributes I should set on my symbol so that the netlister will use the subcircuit? - Is there a simpler way I should go about this? For now I'm mostly interested in what my driver can do to the gate of the MOSFET, and for now less about what the MOSFETs do to their load (a DC motor). _______________________________________________ geda-user mailing list [email protected] http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
