This manual describes how to implement the digital mixed-signal flow.
Audience
This manual is written for designers with experience in both digital and custom design environment. Such designers must be familiar with design planning, placement and routing, block implementation, chip assembly, and design verification. Designers must also have a solid understanding of UNIX and Tcl/Tk programming.
This document applies to the Innovus user interface. See the document for the Innovus Stylus user interface.
How to Use This Document
The Mixed Signal Interoperability Guide covers many different Mixed signal related topics and has detailed descriptions on various OpenAccess-based flows supported by the tools involved in this flow. This portion of the document attempts to guide you to the pertinent content in this documentation, based on what you wish to accomplish so that the study of the documentation becomes a task-based approach. You can go directly to the recommended sections of the document to complete the task at hand.
Task: Become familiar with the supported Mixed Signal flows.
Chapter 2 of the document, Overview of Mixed Signal Interoperability, has a brief description of the various supported flows. Once you have decided which flow to use, go to the chapter for that specific flow to view its detailed description. For instance, if you decide to exercise the Analog-on-Top (AoT) flow, go to Chapter 5 - Schematic-Driven Mixed Signal Design Flow.
Task: Set up the various libraries and support files for a Mixed Signal flow.
Chapter 3 - Technology Data Preparation has most of the information needed to prepare the libraries needed for this flow.
If there is a need for special handling of vias in the design, Chapter 13 - Working with Vias in OpenAccess is highly recommended.
Task: Make any special setting required to make the software work properly for Mixed Signal users.
Study the section "Special Settings/Instructions To Enable the Mixed-Signal Flow" in Chapter 4 - Design Data Preparation. Pay special attention to the setOaxMode command in Innovus because this command controls many of the Innovus Mixed Signal features. For more information on the setOaxMode command, refer to the Innovus Text Command Reference.
Task: Bring a design implemented in Virtuoso into Innovus for editing or analysis.
Note that this flow requires an interoperable PDK to be in place before the design can be opened in Innovus. After the interoperable PDK is available, the design can be loaded in Innovus by using the following settings/commands after launching Innovus:
set init_design_netlisttype {OA} # This tells Innovus that the netlist connectivity for the design is coming through an OA DB, as opposed to a Verilog netlist
set init_oa_design_lib {mylib} # This is the name of the library that contains the design to be opened in Innovus
set init_oa_design_cell {top} # This specifies the name of the top level cell in the design. In this example, the cell name is "top".
set init_oa_design_view {layout} # This tells Innovus which view of the cell "top" to open. In this example, the layout view is opened.
set init_oa_ref_lib {gsclib045} # This tells Innovus which reference/technology is being used for this design. In this example, gsclib045 is the interoperable PDK to be used.
set init_pwr_net {VDD AVDD} # Power nets being used in the design are defined. In this example VDD and AVDD are being used as power nets in our design.
set init_gnd_net {GND AGND} # Ground nets being used in the design are defined. In this example GND and AGND are being used as ground nets in our design.
set init_mmmc_file {viewDefinition.tcl} # This setting is optional as it is used if you are bringing the design into Innovus to perform timing analysis or optimization. It points to the view definition files that are used to set up the environment for Multi Mode Multi Corner (MMMC) analysis and implementation.
init_design # This is the actual command that will load the design into Innovus
Refer to the Static Timing Analysis for Mixed Signal Designs for more details on how Virtuoso-based designs can be imported into Innovus.
Task: Understand the details of the specific flow that you have decided to use.
If you are going to be using the Analog-on-Top (AoT) flow, refer to Chapter 5 - Schematic-Driven Mixed Signal Design Flow and Chapter 6 - Virtuoso Digital Implementation.
If you are going to be using the Digital-on-Top (DoT) flow, refer to Chapter 8 - Netlist-Driven Mixed Signal Design Flow.
If you will be bringing the entire Mixed Signal design from one implementation platform to another (Virtuoso to Innovus, or Innovus to Virtuoso), you will be exercising the Mixed-Signal-on-Top flow (MSoT). MSoT flow supports Mixed Signal STA, Mixed Signal Floorplaning, Mixed Signal Routing, and so on.
Task: Run Static Timing Analysis on a Mixed Signal design coming from Virtuoso with digital content
Refer to Chapter 20 - OpenAccess Database Interoperability Checker, followed by Chapter 18 - Static Timing Analysis for Mixed Signal Designs.
Task: Floorplan the design in Virtuoso and Innovus, and share the floorplan information between the two cockpits
Refer to Chapter 7 - Quick Abstract Inference.
Refer to Chapter 5 - Schematic-Driven Mixed Signal Design Flow and study the section titled “Controlling Floorplanning Information Read in from the OpenAccess Cellview”.
Related Documents
For information on installing Cadence products, see Cadence Installation Guide.
For information on library structure, the library definitions file, and name mapping for data shared by multiple Cadence tools, see Cadence Application Infrastructure User Guide.
Innovus Product Documentation
For more information about the Innovus family of products, see the following documents. You can access these and other Cadence documents with the Cadence Help documentation system.
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Provides information about new and changed features in this release of the Innovus family of products.
Describes how to install and configure the Innovus software, and provides strategies for implementing digital integrated circuits.
Describes the Innovus text commands, including syntax and examples.
Provides information specific to the forms and commands available from the Innovus graphical user interface.
Lists all the Innovus database access commands and provides a brief description of syntax and usage.
Describes how to use the scripts that represent the recommended implementation flows for digital timing closure with the Innovus software.- Contains installation, compatibility, and other prerequisite information, including a list of Cadence Change Requests (CCRs) that were resolved in this release. You can read this file online at downloads.cadence.com.
For a complete list of documents provided with this release, see the Cadence Help online documentation system.
Innovus Stylus Common UI Product Documentation
Provides information on migrating from legacy to the Stylus Common UI version of the Innovus software.
Provides information about new and changed features in this release of the Innovus family of products.
Describes how to install and configure the Innovus Stylus Common UI software, and provides strategies for implementing digital integrated circuits.
Describes the Innovus Stylus Common UI text commands, including syntax and examples.
Provides information specific to the forms and commands available from the Innovus Stylus Common UI graphical user interface.
Provides information about Stylus Common UI database objects.
Virtuoso Documentation
- For information on the design environment n Virtuoso, see Virtuoso Studio Design Environment User Guide.
- For information on database SKILL functions, including data access functions, see Virtuoso Studio Design Environment SKILL Reference
Virtuoso Studio Design Environment Tools
For information on the analog design editing tools, see the following documents:
- Virtuoso Schematic Editor User Guide
-
Design Data Translator's Reference
Virtuoso Layout Suite Tools
- For information on how to perform design tasks with the Virtuoso Layout Suite tools, see the following documents:
- Virtuoso Layout Suite XL: Basic Editing User Guide
- Virtuoso Layout Suite GXL Reference
-
Virtuoso Layout Suite XL User Guide
- For information on custom layout SKILL functions, see Virtuoso Layout Suite SKILL Reference.
- For information on how to use the Virtuoso custom digital placement capability, see Virtuoso Custom Digital Placer User Guide.