Model Statements

General Form:

model name type [ [ param = value ] ... ]

Examples:

 model NPNbjt bjt NPN=yes Bf=100 Js=0.1fa

Often characteristics of a particular type of element are common to a large number of instances. For example, the saturation current of a diode is a function of the process used to construct the diode and also of the area of the diode. Rather than describing the process on each diode instantiation, that description is done once in a model statement and many diode instances refer to it. The area, which may be different for each device, is included on each instance statement. Though it is possible to have several model statements for a particular type of device, each instance may only reference at most one model. Not all device types support model statements.

The name in the model statement becomes the type in the instance statement. The type field is the ADS Simulator-defined model name. Any parameter value not supplied will be set to the model's default value.

Most models, such as the diode or bjt models, can be instantiated with an instance statement. There are exceptions. For instance, the Substrate model cannot be instantiated. Its name, though, can be used as a parameter value for the Subst parameter of certain transmission line devices.