The Parameter Sweep dialog allows you to set the analysis conditions for parameter sweep. You could specify varying values for power, model or global parameters. The conditions set in this dialog are output as the .STEP statements of the simulator.
If you set a variable or an equation for a circuit value or model parameter value in the Properties Panel, then LTspice varies these values during Transient, DC and AC analysis. For example, you could associate a variable “RVAL” with a resistor, and specify an equation for a second resistor as “RVAL*2+10K”. When the analysis is performed, the “RVAL” value varies between the Start and Stop values, using the specified Step value.
- Variables that you define in the Properties Panel, SPICE parameter fields, must be enclosed by curly brackets.
- Values that you specify in this dialog must not contain spaces.
To make this dialog available, select Parameter Sweep in the Analysis Conditions dialog. Launch it by double-clicking an item in the Parameter Sweep folder in the SPICE Controller Manager, Analysis Tree, or by right-clicking it and selecting Open.
Parameter Sweep 1
| Item | Description | |
|---|---|---|
| Sweep object | Input the sweep target. The following sweep targets can be selected. | |
| Model parameter | If selected, then values are specified for model parameters. | |
| Global parameter | If selected, then values are specified for global parameters. A global parameter could be a resistance value for a component defined within the netlist, for example. | |
| Power | If selected, then values are specified for power parameters. | |
| Parameter name | Input the reference designator of the sweep target. | |
| Step | Analysis is performed from a sweep start value through a sweep end value by splitting with the specified number of points. | |
| Start | Input a sweep start frequency. | |
| Stop | Input a sweep end frequency. | |
| Step | Input the sweep variation. | |
| Linear | Analysis is performed from a sweep start value through a sweep end value by splitting using the specified step value. | |
| Start | Input a sweep start frequency. | |
| Stop | Input a sweep end frequency. | |
| Step | Input the sweep variation. | |
| Decade | Analysis is performed from a sweep start value by splitting using the specified number of points on a decade basis. | |
| Start frequency | Input a sweep start frequency. | |
| Stop frequency | Input a sweep end frequency. | |
| Points per decade | Input the number of points for the decade. | |
| Octave | Analysis is performed from a sweep start value by splitting using the specified number of points on an octave basis. | |
| Start frequency | Input a sweep start frequency. | |
| Stop frequency | Input a sweep end frequency. | |
| Points per octave | Input the number of points for the octave. | |
| List | Specify the required values as a list, with a separate value on each row. The list of values do not have to form a regular pattern. There is no limit to the number of values that you can specify. | |
| OK | Saves the specified settings to the to the SPICE Controller Manager, and closes the AC Sweep - SPICE Controller Manager dialog. | |
| Cancel | Closes the AC Sweep - SPICE Controller Manager dialog without saving any unsaved changes. | |
| Apply | Saves the specified settings to the SPICE Controller Manager. The AC Sweep - SPICE Controller Manager dialog remains open. |
