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13 Model and Device Parameters

The following tables summarize the parameters available on each of the devices and models in (note that for some systems with limited memory, output parameters are not available). There are several tables for each type of device supported by . Input parameters to instances and models are parameters that can occur on an instance or model definition line in the form "keyword=value" where "keyword" is the parameter name as given in the tables. Default input parameters (such as the resistance of a resistor or the capacitance of a capacitor) obviously do not need the keyword specified.

Output parameters are those additional parameters which are available for many types of instances for the output of operating point and debugging information. These parameters are specified as "@device[keyword]" and are available for the most recent point computed or, if specified in a ".save" statement, for an entire simulation as a normal output vector. Thus, to monitor the gate-to-source capacitance of a MOSFET, a command

        save @m1[cgs]

given before a transient simulation causes the specified capacitance value to be saved at each timepoint, and a subsequent command such as

        plot @m1[cgs]

produces the desired plot. (Note that the show command does not use this format).

Some variables are listed as both input and output, and their output simply returns the previously input value, or the default value after the simulation has been run. Some parameter are input only because the output system can not handle variables of the given type yet, or the need for them as output variables has not been apparent. Many such input variables are available as output variables in a different format, such as the initial condition vectors that can be retrieved as individual initial condition values. Finally, internally derived values are output only and are provided for debugging and operating point output purposes.

Please note that these tables do not provide the detailed information available about the parameters provided in the section on each device and model, but are provided as a quick reference guide.