LTSpice: how to add a transformer?

You can just place two inductances and something like "K1 L1 L2

0.999" (text) next to them (or anywhere on the schematic, it's more readable if it's close to the inductors involved). There are more complicated models, including capacitance and resistance, of course, and you can also create one using sources to emulate the coupling.

You should find at least a couple examples of transformers in the examples/educational directory under LTSpice: transformer.asc and transformer2.asc.

You'd do well to join the Yahoo group for LTSpice, where you will find examples of transformers, discussions about transformer models, and lots of helpful folk.

Cheers, Tom

You add two inductors and then add a SPICE directive (Edit->SPICE directive) along the lines of, "K1 L1 L2 0.99" which says L1 and L2 make up a transformer with a coupling coefficient of 0.99. (And in case you don't recall: The turns ratio goes with the square root of inductance -- if L1 is 1mH and L2 is 4mH, L1 has "x" turns and L2 has "2x" turns.)

See the example: c:\\program files\\ltc\\swcadiii\\examples\\educational\\transformer.asc. For a three-winding transformer, there's transformer2.asc.

---Joel

For blither.... ouch...

For schematics

For symbols.

DNA