Defines a model for a diode, transistor, switch, lossy transmission line or uniform RC line
Some circuit elements, for example, transistors, have many parameters. Instead of defining every transistor parameter for every instance of a transistor, transistors are grouped by model name and have parameters in common. The transistors of the same model can have different sizes and the electrical behavior is scaled to the size of the instance.
Syntax: .model <modname> <type>[(<parameter list>)]
The parameter list depends on the type of model. Below is a list of model types:
| Type | Associated Circuit Element |
| SW | Voltage Controlled Switch |
| CSW | Current Controlled Switch |
| URC | Uniform Distributed RC Line |
| LTRA | Lossy Transmission Line |
| D | Diode |
| NPN | NPN Bipolar Transistor |
| PNP | PNP Bipolar Transistor |
| NJF | N-channel JFET model |
| PJF | P-channel JFET model |
| NMOS | N-channel MOSFET |
| PMOS | P-channel MOSFET |
| NMF | N-channel MESFET |
| PMF | P-channel MESFET |
| NIGBT | N-channel IGBT |
| PIGBT | P-channel IGBT |
| VDMOS | Vertical Double Diffused Power MOSFET |
See the description of the circuit element for a list of which parameters are instance specific and which are common to a model.