Transformers

Transformer setup is achieved by editing its .subckt data. It should be noted that the turns ratio is given by N=sqrt(Ls/Lp) and k= co-efficient of coupling, typically about 0.99.

There are currently 12 base transformer symbols with models. Single, dual, triple and quad in both single coil and center tapped coil format. Have a look at the models (SuperSpice.lib) to see the syntax. The main feature of the mutual inductance syntax is that every coil that is connected to every other coil must be specified. Since we have already done this, copy the "K" lines and use them directly in new models, even if you change the existing wiring to include series resistance's and leakage inductance's. If you want only say, 3 coils, simply make dummy resistor connections with the relevant mutual inductance's removed from the model. Spice needs to see the pins connected to something.

Copy these models to thier own library file before modifying and using them.

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