AC Analysis Statement (ac)

Only the Spectre solver supports AC analysis. The APS solver also does not support AC analysis.

Using the Spectre solver, the AC analysis statement linearizes the circuit about the DC operating point and computes the response to a given small sinusoidal stimulus. You can specify, at most, one AC analysis in your analog simulation control file.

Name ac{ parameter=value }

When you run an AC analysis using the AMS Designer simulator with the Spectre solver, the following differences apply:

• You can sweep only frequency during an AC analysis.

• You cannot sweep temperatures, component instance parameters (dev), component model parameters (mod), or netlist parameters (param).

When the AMS Designer simulator runs standalone, it writes the results of the AC analysis to a parameter storage format (PSF) file. By default, the software stores the PSF file in a directory called ascf.raw (where ascf is the name of the analog simulation control file). You can use the rawfile parameter of the options statement in the analog simulation control file to specify the location of the file.

You use the Tcl probe command to specify probes you want to run during the AC analysis.

You can specify the following parameters and values with the ac statement. Values listed in the parameter syntax are the defaults.

Related Topics

• Mixed-Signal DC Initialization