LTSpice

LTSpice is a free electronics simulation program from Analog Devices (originally made by Linear Technologies).

It can be downloaded from their website: https://www.analog.com/en/design-center/design-tools-and-calculators.html

If the component you want to use in your circuit is not available you can import one.

LTSpice models are available in two types:

• Model (.mod, model)

- these are simple components such as transistors and diodes

• SubCircuit (.sub, subckt)

- these are more complex parts made up of simpler Spice parts (diodes, transistors, resistors etc)

comp (component)

sub ()

lib (library)

inc (include)

sym (symbol)