Virtuoso AMS Environment User Guide
Elaborating, Simulating, and Plotting Results
Field |
Effect |
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Currents at |
Specifies whether to create current probes. The probes |
terminals or ports |
return the current of electrical terminals or ports but return |
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nothing if the terminals or ports have disciplines from the |
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discrete domain. |
Levels of |
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hierarchy to save |
|
All |
Specifies that currents are to be probed and saved for the |
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selected level and all lower levels of the hierarchy. |
Levels |
Specifies the number of levels (including the selected level) |
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that are probed for current. If you probe an instance for |
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both voltage and current, this Levels value is ignored and |
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the Levels value for Voltages/Signals is used for both. |
Default database name |
Specifies the name of the default database for signals. For |
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information about customizing the database, see “Defining |
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Databases for Waveforms” on page 281. |
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3. When you are done changing options, click OK to save your changes.
Creating Probes
You can use Tcl commands to create voltage and current probes explicitly. The AMS environment, however, eases that task by allowing you to create probes by selecting objects from schematics and hierarchical tree views.
1. Choose AMS – Save/Plot.
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Elaborating, Simulating, and Plotting Results
The AMS Save/Plot window appears.
The first line in the table describes the default probe, which saves waveforms for the entire design. You can remove the check mark from the Save column for this line, but you cannot remove the line from the table. If you know which information you need, you can turn off the default probe and use other rows in the table to specify more targeted probes.
The following table describes the controls and fields.
Field |
Effect |
|
|
Name |
The name of the probe. When you type in information to |
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create a probe, you must type in the name before filling in |
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the other probe information. |
Object |
An icon representing the objects to be probed. |
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A net or signal. For nets or signals, the Depth |
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column is not applicable (N/A). |
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A terminal. For terminals, the Depth column is not |
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applicable (N/A). |
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All the input ports of the instance. |
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All the output ports of the instance. |
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All the ports of the instance. |
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All the ports and the internal signals of the |
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instance. |
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Elaborating, Simulating, and Plotting Results
Field |
Effect |
|
|
Type |
An icon representing the type of measurement performed |
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by the probe. |
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Voltage. Returns the voltage of electrical nets or |
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the digital value of nets that have disciplines from |
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the discrete domain. |
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Current. Returns the current of electrical |
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terminals or ports but returns nothing if the |
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terminals or ports have disciplines from the |
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discrete domain. |
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Current and voltage both. |
Depth |
An integer specifying how many scope levels to descend |
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when searching for objects to probe. |
Database |
The database to receive the probe data. Which databases |
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are available depends on the specifications in the AMS |
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Databases window. For more information, see “Defining |
|
Databases for Waveforms” on page 281. |
Save |
Specifies whether the waveforms produced by the probe |
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are saved. |
Plot (column) |
Specifies whether the waveforms produced by the probe |
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are plotted during simulation. |
Select from |
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Schematic |
Opens the Schematic Editing window, if it is not open, so |
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that you can select objects in the schematic. The objects |
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you select are added to the AMS Save/Plot table. For more |
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information, see “Selecting Instances from the Virtuoso |
|
Schematic Editing Window” on page 282. |
Navigator |
Opens the Scope Navigator window so that you can select |
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instances from a tree representation of the design |
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hierarchy. The instances you select are added to the AMS |
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Save/Plot table. For more information, see “Selecting |
|
Instances from the Scope Navigator” on page 284. |
Save only |
Specifies that probes added to the AMS Save/Plot window |
|
by selecting objects are added with only the Save column |
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checked. You can switch between Save only and Save |
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and plot at any time during the probe creation process. |
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Elaborating, Simulating, and Plotting Results
Field |
Effect |
|
|
Save and plot |
Specifies that probes added to the AMS Save/Plot window |
|
by selecting objects are added with both the Save and the |
|
Plot columns checked. You can switch between Save and |
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plot and Save only at any time during the probe creation |
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process. |
|
The effect of checking both the Save and Plot columns |
|
depends on the simulation Run Mode setting. |
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In the GUI mode, the waveforms are marched. |
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In the Batch mode, the waveforms are saved and then |
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plotted at the end of the simulation. |
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In the Tcl mode, the waveforms are only saved. |
Databases |
Opens the AMS Databases window so that you can specify |
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the characteristics of waveform databases. For guidance, |
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see “Defining Databases for Waveforms” on page 281. |
Remove |
Removes highlighted rows from the AMS Save/Plot table. |
Plot (button) |
Plots or replots the waveforms saved by the probes |
|
designated by checks in the Plot column. Only waveforms |
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saved during previous simulations can be plotted this way. |
|
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2.(Optional) Use the AMS Databases window to define the databases you need. For guidance, see “Defining Databases for Waveforms” on page 281.
3.Define the probes. You can:
Click an empty row and fill in the name and then the other columns to create a probe.
Click the Schematic button to select objects to be probed from the schematic editing window.
For guidance, see “Selecting Instances from the Virtuoso Schematic Editing Window” on page 282.
Click the Navigator button to select instances to be probed from a tree display of the hierarchy.
For guidance, see “Selecting Instances from the Scope Navigator” on page 284.
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Right-click on a module in the hierarchy editor Tree view of a design configuration and select Save Instance Data.
Copy existing rows to new rows and then modify the new rows as necessary.
For guidance, see “Copying and Pasting Within Tables” on page 285.
Defining Databases for Waveforms
The Database column in the AMS Save/Plot window specifies the databases to be used for the waveforms returned by the various defined probes. There is a predefined default database named waves, but you can also define additional databases by following these steps:
1.In the AMS Save/Plot window, click Databases.
The AMS Databases form appears.
2.(Optional) Click the right-facing arrow at the upper, right-hand corner of the table twice. The form expands to display additional columns.
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