Does anybody know how of a transformer that I can add to the component
library for Linear Technologies SwitcherCAD? I'm trying to simulate a
switching power supply.
I have never used SWCAD but do know it is optimized especially for
switchers. In a pinch, certainly you can find an ideal transformer, then
parallel it with an inductor equal to the magnetizing inductance, and in
series, with the whole assembly, add a combo of R+Ls where R is the
winding resistance and Ls is the leakage inductance, which can be taken
to be 1% of magnetizing inductance. Add a secondary series R+L as well.
This will give a first order approximation. For an exact simulation
SWCAD should have provisions for a Jiles-Atherton [sp?] transformer
simulation, mainly to simulate core losses, and this requires
information pertaining to core material and geometry- much more
detailed. You can also estimate the loss and represent this in the first
order model by a resistor Rm in parallel with the magnetizing
inductance, which is still useful for obtaining bounds.