2 Getting Started

Product and Installation Information

The Voltus-Fi-L product is launched within the Virtuoso Platform. To use this product, you must have the Virtuoso IC 6.1.8 release version.

To check whether this product is available in your Virtuoso^® Studio Design Environment, type the following in the UNIX window, shell, or xterm:

vfibatch -v

This prints the product version available in your Virtuoso Studio Design Environment.

For basic information and procedures required to install Cadence^® products, see Cadence Installation Guide.

For information about how to configure the Virtuoso^® Studio Design Environment, see “Setting up the Virtuoso Software”, in Virtuoso Software Licensing and Configuration User Guide.

Voltus-Fi will be obsolete in the next base IC release. The “next-generation” solution, Voltus-XFi, is available in this release of Virtuoso. It offers significant improvements to the overall EM-IR flow, including a unified use model, simplified simulation setup, and faster loading of results. The Voltus-XFi license is backward compatible and can be used to run Voltus-Fi if needed.

Supported and Compatible Platform

Voltus-Fi-L is supported only on the following platform:

Linux (only 64-bit)

Using the CDS_AUTO_64BIT Environment Variable

To run 64-bit versions of all or some applications, complete the following steps before starting the software:

If you are using the lnx86 operating system, verify that it supports 64-bit applications.
Set the CDS_AUTO_64BIT environment variable.
For example,
- To run all applications in 64-bit mode, run the following command:
```
setenv CDS_AUTO_64BIT ALL
```
- To run specific applications in 64-bit mode, such as Spectre and Voltus-Fi-L, and all other applications in 32-bit mode, run the following command:
```
setenv CDS_AUTO_64BIT spectre:vfibatch 
```

Starting the Software

You can run Voltus-Fi-L interactively from the GUI, or you can execute it as a batch command. For details, see the following sections:

Before running Voltus-Fi-L, ensure that the prerequisites detailed below are met.

PreRequisites for Running Voltus-Fi-L

Ensure that the following are available before running Voltus-Fi-L:

A simulation run using either the vavo-db or the PSF data.
Parasitic resistance and capacitance from the power and ground nets, performed to create an extracted view of the design using Quantus QRC.
For more information, see the “IR/EM Analysis Flow” chapter.
An EM rule file that contains the EM reliability rules that need to be specified for EM analysis. For example, the rule specifying different current limits with respect to width, length, and temperature. These rules are specified in the technology file.
This is required only for EM analysis. For more information about specifying the EM rules, see the “EM Rules Specification” chapter.

Running Voltus-Fi-L in Batch Mode

Voltus-Fi-L can be run as a batch command, which means it runs from Virtuoso in a no-graph mode. Batch mode is typically used to perform the initial pass or fail analysis of the design’s power-grid networks.

After running the analysis in batch mode, use the interactive GUI to view and analyze the results of the analysis.

For details of running Voltus-Fi-L in the batch mode, see the following topics in the “Batch Mode Execution” chapter:

The details of running Voltus-Fi-L in the GUI mode are provided below.

Running Voltus-Fi-L in the GUI Mode

This section covers the details of how to run Voltus-Fi in the GUI mode including all the data requirements. The following topics are covered in this section:

Data Requirements for the GUI Flow

The following inputs are required for running the extracted view flow in the GUI mode:

Simulation directory – specifies the path of the Spectre simulation directory containing the vavo_db database or the PSF database.
qrcTechFile/ICT file or emDataFile – specifies the path of the Quantus QRC tech file/ICT file/emDataFile.
The tech file is only required for the EM analysis flow.
QRC directory – specifies the location of the Quantus QRC run.
QRC run name – specifies the Quantus QRC run name.
Layermap file (optional) – specifies the layermap file that provides the mapping between the layer names in the simulation database to the layer names in the technology file. If not specified, the software assumes that the layer names are same.
The layermap file is only required for the EM analysis flow.
Hierarchy (optional) – specifies the hierarchy name.
Pres_cell name (optional) – specifies the presistor cell name.

Launching Voltus-Fi-L from Virtuoso Schematic Editor L

Before viewing the IR drop and EM analysis results in the Voltus-Fi-L GUI, you will be performing the following tasks:

Starting the Virtuoso Studio Design Environment

Once you have set up the Virtuoso Studio Design Environment, you can start Virtuoso by typing the following in the unix, shell, or xterm window:

virtuoso &

The Command Interpreter Window (CIW) opens. You interact with the design environment from the CIW.

Figure 2-1 Command Interpreter Window (CIW)

The title bar of the CIW contains the following information:

The name of the workbench you are running (for example, Virtuoso).
The path to the log file (CDS.log) that records the ongoing events of the design session. The content of the log file is displayed in the output area.

Using the CIW to Open the Virtuoso Schematic Editor L

You can use the CIW to open the schematic view of the design you want to analyze. From the Main menu, you can either use the Tools menu or the File menu to access your design.

Using the File Menu

For information about how to open the schematic view of Virtuoso from the File menu in the CIW, see, “Working with Cellviews”, in the Virtuoso Design Environment User Guide.

Using the Tools Menu

To open the schematic view of the design from the Tools menu, choose Tools – Library Manager. This is shown below.

Figure 2-2 Command Interpreter Window – Opening the Library Manager Form

The Library Manager form opens. This is shown below.

Figure 2-3 Library Manager Form

For more information on the Library Manager, see the Cadence Library Manager User Guide.

Opening a Schematic View in the Library Manager

In the Library Manager form, you can choose to display library information (library, cell, view, file, category) using either list boxes (in View – Lists mode) or a hierarchical tree structure (in View - Tree mode).

The information provided below is for Views – Lists mode.

To select a library and its corresponding cell and view on the Library Manager form, click the item names in the order: Library, Cell, and View. You can select a specific item that is not visible in the list box by typing the first part of the name in the active field at the top of the list box. As you type, the list scrolls to any matching names.

Once you have selected the schematic view, doubleclick the view to open the design in Virtuoso Schematic Editor L. This is shown below.

Figure 2-4 Virtuoso Schematic Editor – Displaying the Design

You can also open the schematic view of the design by using the SKILL function, vsaOpenSchematic.

Descending into Design Hierarchy

In the Schematic Editor, before you run Voltus-Fi-L, you need to descend into the design hierarchy. A design hierarchy consists of many levels of a single design. When you descend into the design hierarchy, you view the extracted layout of the design you want to analyze.

You can descend into the design by using the SKILL function, vsaDescendView.

In the GUI, to descend into the design hierarchy, follow these steps:

In the Virtuoso Schematic Editor L, choose Edit – Hierarchy – and Descend Read. Choose the Descend Edit option to make any change in the extracted layout.
Figure 2-5 Virtuoso Schematic Editor L – Descending into Design Hierarchy

You can also double click the instance to which you want to descend. The Descend form opens.
Figure 2-6 Descend Form – Selecting the Design View
In this form, select the name of the extracted view from the options provided in the View cyclic field. In the example shown in the figure above, the extracted view is av_extracted_vco_oa.
Click read to open the extracted view for reading. You can select edit if you want to modify something in the extracted view.
Choose where you want to open the extracted view by selecting Open in – new tab, current tab, or new window.
Click OK.
The selected view of the instance opens in Virtuoso^® Layout Suite L. This is shown in the figure below.
Figure 2-7 Virtuoso Layout Suite L – Displaying the Selected Design View

Launching Voltus-Fi-L

After opening the detailed view of the selected instance of the design, open the Voltus-Fi-L GUI from the Main menu of the Virtuoso^® Layout Suite by performing the following steps:

Choose Launch – Plugins – Voltus-Fi-L. This is shown below.
Figure 2-8 Running Voltus-Fi-L from the Layout Suite
The Voltus-Fi-L console opens. This is shown below.
Figure 2-9 The Voltus-Fi-L Console
The following main menus of Voltus-Fi-L are available:
- IR/EM Analysis
- Help

In addition to the menus, there is a Stop Process button in the console. This button is enabled when you run a process. This shown using a red highlighted text box in the above figure. Click this button to stop a process while it is running.

Log Files for Voltus-Fi-L

When you run Voltus-Fi-L either in the GUI or in the batch mode, a standalone log file is created to record the complete Voltus-Fi-L session. This file is created in addition to the CDS.log file that records the ongoing events of the design session in Virtuoso. This Voltus-Fi-L-specific log file is saved in the following location by default.

working_dir/vfi.log#

Example:

working_dir/vfi.log19

For each session, a new log file is created, such as vfi.log1, vfi.log2, and so on. You can save up to twenty log files, after which the last log file, vfi.log20, will be overwritten in subsequent sessions.

If you do not have permissions in the working directory, these files will be saved in your home directory.

A sample log file is shown below.

*****************************************************************

@(#)$CDS: virtuoso version 6.1.7-64b 01/24/2017 20:25 (sjfhw312) $

sub-version  IC6.1.7-64b.main.372

Voltus-Fi v06.17-e282_1

Checkout of license "Voltus_Power_Integrity_Fi_L" was successful

INFO : Loading results for IR plots display

INFO : Loading results done

Time Msg : Time taken 2.00 seconds. User cpu 1.00 seconds. System cpu 1.00 seconds.

Time Msg : Time taken 2.00 seconds. User cpu 1.00 seconds. System cpu 1.00 seconds.

INFO : Loading results for IR plots display success.

Time Msg : Time taken 2.00 seconds. User cpu 1.00 seconds. System cpu 1.00 seconds.

Time Msg (IR plot) : Time taken 0.00 seconds. User cpu 0.00 seconds. System cpu 0.00 seconds.

INFO : Loading results for IR plots display

INFO : Loading results done

Time Msg : Time taken 1.00 seconds. User cpu 1.00 seconds. System cpu 0.00 seconds.

Time Msg : Time taken 1.00 seconds. User cpu 1.00 seconds. System cpu 0.00 seconds.

INFO : Loading results for IR plots display success.

Time Msg : Time taken 1.00 seconds. User cpu 1.00 seconds. System cpu 0.00 seconds.

Time Msg (IR plot) : Time taken 0.00 seconds. User cpu 0.00 seconds. System cpu 0.00 seconds.

INFO: layout X-Y are 450:1005 by 90265:41155

INFO: layout X-Y are 1450:10790 by 86985:39000

INFO: layout X-Y are 1450:10790 by 86985:39000

Accessing Documentation and Help

You can access the Voltus-Fi-L documentation and help system using the following methods:

Launching Cadence Help from the Command Prompt

Change to the following directory:
```
installation_dir/tools/bin
```
Enter the following command:
```
./cdnshelp
```

After launching Cadence^® Help, press F1 or choose Help – Contents to display the help page for Cadence Help.

For more information see the Cadence Help manual.

Accessing Documentation and Help from the GUI

The software provides the following two methods to access documentation and help from the GUI:

Select Help on the Main Menu

Click the Help button in the Voltus-Fi-L console. The following submenus are available:

Voltus-Fi User Guide: opens the Voltus-Fi Custom Power Integrity Solution L User Guide.
What’s New: opens the Voltus-Fi Custom Power Integrity Solution L What’s New chapter in the Virtuoso What’s New.
About: provides the version information for the software.

Select Help on a Voltus-Fi-L Form

Click the Help button on the bottom right corner of a form. Clicking the Help button opens the Voltus-Fi-L user guide entry for the form in the Cadence Help window.

Other Source of Information

You can also get help on Cadence products by selecting Customer Support on the Help menu. The Customer Support submenu provides access to the following Cadence resource:

Cadence Online Support: Opens Cadence Online Support in your browser.
You are required to have a Cadence Online Support account to access these materials.

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Voltus-Fi Custom Power Integrity Solution L User GuideProduct Version IC23.1, August 2023

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Getting Started