Running a Simulation and Viewing Results Using PSpice

The following section discusses how to use PSpice from Capture to create a simulation profile, run a simulation, and view the simulation results in the PSpice Probe window.

The remaining topics cover:

Creating a new simulation profile

A simulation profile (*.SIM) saves your simulation settings for an analysis type so you can reuse them easily. You can create a new simulation profile from scratch or import the settings from an existing simulation profile. Importing settings from existing simulation profiles allows you to reuse the settings from other simulation profiles.

Capture allows you to create a new simulation profile by importing settings from a simulation profile that exists in the same project or in another project.

To create a new simulation profile, do the following:

1. Choose PSpice - New Simulation Profile.
   The New Simulation dialog box appears.
2. In the Profile Name text box, type a name for the profile (such as the name of the analysis type for the new profile).

3. You may want to import the simulation settings from an existing profile to the new profile. 

   • To select a profile from the current project, click the Inherit From drop-down list. This list shows all the simulation profiles in the current project. 

   • To select a profile from another project, click the browse button to navigate to the desired simulation profile.

4. Click Create to create the profile and display the Simulation Settings dialog box.
   The Simulation Settings dialog box appears.

5. In the Analysis tab, specify the analysis type.
   Specify the relevant settings in the General and other tabs.

   Check whether you have the nom.lib added as a GLOBAL library under the Library category of the Configuration Files tab. This "master library" file calls out the other libraries that Cadence supplies along with the installation. It takes time for PSpice to scan each library file. PSpice creates an index file, called <filename>.IND, to speed up the search process. The index file is re-created whenever PSpice senses that it might be invalid.

   If this nom.lib is not there then Capture-PSpice interface will not be able to detect the Cadence-supplied PSpice libraries to be used in the simulation, so add this globally. The nom.lib resides in the <install dir>/tools/pspice/library folder.

6. Click OK to save the settings and close the dialog box.

 After creating a new profile, you can edit the settings with the PSpice – Edit Simulation Settings command.

Shortcut

 Keyboard: ALT+S+N

Creating a simulation netlist

 When generating a PSpice netlist, you can choose between two types of netlist formats:

• Flat netlist
• Hierarchical netlist

Use the PSpice tab on the Create Netlist dialog box to generate a customized PSpice netlist.

Viewing a simulation netlist

 You can view the most recent simulation netlist for a selected design, or the current design.

 To view a simulation netlist:

1. In the project manager, select the design for which you want to create a netlist, or open a schematic page.
2. From the PSpice menu, choose View Netlist.

Running a simulation

 You can simulate your Capture design using PSpice, provided that there are PSpice models for the parts in your design. PSpice and Capture are fully integrated.

 To run a simulation:

1. In the project manager, select a design to simulate, or open a schematic page.
2. In the project manager, select a simulation profile.
3. From the PSpice menu, choose Run or press the F11 function key.

 PSpice does the following:

• Checks design rules for your design.
• Creates a simulation netlist for PSpice.
• Opens PSpice using the netlist created from your design.

PSpice creates an output file (.OUT) as the simulation progresses. It contains bias point information, model parameter values, error messages, and so on. If the simulation fails, you can view the output file to see the error messages.

If the simulation completes successfully, PSpice produces a data file (.DAT). This is the file PSpice uses to display the simulation results. To see marker simulation results, the schematic must be open.

Viewing the results as the simulation progresses

You can choose to view results as a simulation progresses or after a simulation is completed.

 To view results as a simulation progresses:

1. From the PSpice menu, choose Edit Simulation Settings.
   The Simulation Settings dialog box appears.
2. In the Probe Window tab, select the Display Probe window check box.
3. Select the during simulation option.
4. Click OK.

Viewing the most recent simulation results

 You can view the most recent simulation results for a schematic. If the schematic was simulated with more than one profile, you can choose which profile results to view.

 To view the most recent simulation results:

1. Open the schematic for which you want to view simulation results. You must do this to see marker results.
2. In the project manager, select the simulation profile you want to be active.
3. From the PSpice menu, choose View Simulation Results, or press the F12 function key.

Viewing the output file

 To view the most recent output file:

1. In the project manager, choose the simulation profile for which you want to see the output file.
2. From the PSpice menu, choose View Output File.

Editing simulation settings

 Simulation profiles can be edited in Capture and PSpice.

To edit simulation settings from Capture

1. Choose PSpice – Edit Simulation Settings. The Simulation Settings dialog box appears.
2. Click the tab for the settings you want to change.
3. Edit the settings and click Apply.
4. Repeat steps 2 and 3 until you have changed all the settings you need.
5. Click OK.

Shortcut

 Keyboard: ALT+S+E

Placing markers

 To view the markers in the simulation results, the schematic must be open.

 To place markers in your design:

1. From the PSpice menu, choose Markers.
2. Select the marker you want to place.
3. Drag the marker symbol attached to the cursor to the location where you want to place it.
4. Click to place the symbol.
5. Repeat steps 3 and 4 until you have that you want.
6. Press the Esc key to end the marker mode, or right-click and select the End Mode.

Showing, hiding, and deleting markers

You can show all, hide all, or delete all markers. Showing or hiding markers in the schematic also shows or hides the trace results in the Probe window.

To show all, hide all, or delete all markers:

1. From the PSpice menu, choose Markers.
2. Select the Show All, Hide All, or Delete All option.

Simulating and viewing the results of multiple profiles

You can select one profile or multiple profiles to be simulated or viewed. If you select only a single profile for simulation, it is handled as though you chose the Run command. If you select a file for viewing, it is handled as though you chose the View Simulation Results command.

To simulate multiple profiles

1. In the project manager, choose the simulation profiles you want to simulate.
2. From the PSpice menu, choose Simulate Selected Profile(s).

PSpice opens and processes the profiles using the simulation queue.

To view the results:

1. Close the simulation queue, but leave PSpice active.
2. The Probe window is active, but no traces are visible.
3. From the PSpice File menu, choose Open.
4. Select the .DAT files that you want to view and click the Open button. A tab for each of the .DAT file you selected appears at the bottom of the Probe window.
5. From the PSpice Window menu, choose Display Control.
6. Select a profile for which you want to display the results.
7. Click Restore.
8. Repeat steps 4, 5, and 6 for all the profiles you want to view.

You can then click each tab to view the displayed results.

Making a simulation profile active

To simulate a design with a specific simulation profile, or to view the most recent results of a specific simulated profile, you must activate the profile.

To activate a simulation profile:

1. In the project manager, choose the simulation profile you want to activate.
2. From the PSpice menu, choose Make Active.