Cadence AWR Design Environment Version 16 Enables Integration of Heterogenous Technologies
5G wireless systems and connected devices are proliferating across every imaginable industry, driving technology leaders to capitalize on market opportunities for RF-enabled products defined and differentiated by performance, size and cost. Traditionally, custom or proprietary integrated circuit (IC) designs leveraging the latest advanced technology node have been the path forward to realize differentiation, but today’s complex designs are moving beyond the chip.
RF and mixed-signal engineering efforts have embraced not only diverse semiconductor processes but advanced cross-fabric packaging and system-in-package (SiP) and package-in-package (PiP) technologies, as well as 3D ICs implemented using advanced interconnect technologies. Successful products require every possible component interaction which might influence the overall performance of the final product be considered at the system level throughout the design, analysis and signoff phases of development. All electrical factors affecting the outcome—micro and macroscopic—must be considered.
To win in the highly competitive 5G wireless markets, companies require electronic design automation (EDA) solutions enabling complete and comprehensive RF workflows from the chip to the system. To this point, engineering teams and EDA platforms, as well as simulation and analysis technologies, have converged to ensure valuable engineering time is spent designing—not transferring and translating data from one tool to another. EDA software developers must provide an efficient front to back end interoperable workflow to maximize user productivity.
With the Cadence acquisition of AWR® from National Instruments in 2020, the latest V16 release of the Cadence® AWR Design Environment® platform offers complete and comprehensive RF workflows (see Figure 1).
Heterogeneous integration mitigates the high cost of homogeneous system-on-chip (SoC) solutions by enabling designers to combine proven RFIC and MMIC designs on substrates using newer packaging technologies. Advanced integration methods such as fan-out wafer-level packaging can result in smaller and more efficient systems, yet these highly integrated systems are more complicated and prone to error from the interdependencies of the individual components, the complex network of cross-fabric interconnects and the challenges of assembling cross-platform design data from multiple sources. Platform interoperability is crucial for multi-technology integration across chip, package and board design (see Figure 2).
The new V16 release of AWR Design Environment enables at least a 50 percent reduction in turnaround time through workflow automation. It achieves this by leveraging RF intellectual property (IP) creation and cross-platform simulation, including the IC and package (Virtuoso flow) and the board (Allegro flow). Additionally, integration and interoperability of the Clarity™ 3D Solver and Celsius® Thermal Solver provide electrothermal co-simulation and coupled analyses of large, densely populated designs such as RF front-ends. The RF workflow innovations enabled by the V16 release start with a foundational advance in the way design data and software IP are shared and transferred across manufacturing-specific design platforms. Under the Cadence umbrella, the level of RF integration being introduced with V16 software significantly improves engineering team productivity.
Cadence platforms have continually evolved to address the manufacturing, design and analysis requirements of the process technologies they support, with the design flow automation to manage the development of extremely complex chip, package and board systems. As system-level integration calls for RF design across these different technologies, prior to starting the design, engineers are pulling information from multiple sources: business requirements, reliability constraints, manufacturing processes and supply chain data. For enterprises and large design teams, the need to efficiently share libraries and work with company-authorized and pre-approved component parts and material stackups adds to the challenge of getting a product to market quickly. Interoperability between platforms is necessary to share design data and leverage the unique features of the different tools and reduce or eliminate system integration bottlenecks. Any disconnect between the RF design and manufacturing layout teams consumes engineering resources and directly impacts development schedules.
Imagine RF IP created within AWR software seamlessly integrated into systems designed with newer process technologies and integration methodologies. Development teams now have a highly efficient RF workflow enabling them to extract AWR RF IP/design data and reuse it in the appropriate RFIC, PCB or SiP platform. The V16 release introduces this support for Cadence unified libraries and technology files, establishing interoperability between the AWR, Virtuoso and Allegro platforms.
VIRTUOSO & AWR WORKFLOW
Leveraging a shared architecture and data across the Cadence EDA solutions, the V16 release provides for new RF workflows taking completed designs from Microwave Office software and passing both the schematic and layout to the Virtuoso and/or Allegro platforms. The data is in a unified library and contains all the building blocks of the circuit design. This enables design teams to operate the Allegro SiP or Virtuoso SiP bidirectional implementation flow and Virtuoso RF Solution physical implementation flow as the primary layout tool, with V16 software providing the RF IP schematic and layout design data. The Virtuoso RF Solution flow captures Microwave Office RF IP, enabling designers to represent, integrate and verify the MMIC and embedded RF package design within a single environment. The shared database enables more practical package and IC co-design by simplifying the design flow with easy and reliable access to RF IP developed within Microwave Office.
For example, Microwave Office users can design passive off-chip components through circuit design, optimization and EM verification and then decide the best implementation technology. In some cases, a network of passive components may best be implemented across the IC package boundary. This is often true for RF modules, where the ideal filter design, matching networks and power amplifier output stage load termination use components on both the die and the package substrate.
Within the Virtuoso RF Solution environment, the Spectre® Simulation Platform engine can simulate Microwave Office linear models to support IC and module co-design with embedded Microwave Office IP. The ability to import this IP into the Virtuoso flow extends to MMIC designs. Since most MMIC model and PCell libraries are defined and implemented by the III-V foundry as a process design kit (PDK), the Microwave Office MMIC design flow uses this PDK for the target semiconductor process in the design. The resulting MMIC schematic and layout can then be exported as a unified library design and imported into the Virtuoso environment (see Figure 3).
ALLEGRO & AWR WORKFLOW
Moving from the IC to the board, an RF to PCB workflow starts with the creation of unified libraries and technical files from Allegro parts and board definitions. The new unified library import wizard in V16 software reads the Allegro symbols and footprints in the universal library and technology file and converts this data into an AWR PDK that can be used to create an RF design using standard design entry and simulation methods. After completing the design, the RF engineer exports the schematic and layout of the subcircuit with all the underlying hierarchy into a unified library design using a new utility in AWR V16 software (see Figure 4).
On the back end, the layout engineer needs access to the uncompromised data designed to the company approved bill of materials (BOM) and target manufacturing process. Starting with Allegro-sourced component parts from an organization’s approved BOM and process technologies, the RF engineering and layout teams can then improve design hand-off efficiency and reliability while reducing the back and forth to reconcile differences between RF design and manufacturing requirements.
Historically, large RF structures, such as phased-array feed networks, have been manually sectioned into smaller structures for analysis using the largest and most powerful computing resources. The Clarity 3D Solver 3D EM simulator, used for designing critical interconnect, RFIC, MMIC, module, PCB and SoC designs, overcomes the limitations of legacy EM analysis software by leveraging Cadence’s distributed multiprocessing technology, which delivers virtually unlimited capacity at 10x the speed. Now integrated within AWR software, the Clarity 3D Solver provides RF designers with ready access to high capacity EM analysis for design verification and signoff of large, complex RF/mixed-signal systems, with capabilities beyond those offered by the AWR AXIEM 3D planar and AWR Analyst 3D finite element method (FEM) solvers.
Clarity integration with the Microwave Office platform is an automated process where the entire analysis is fully within the AWR environment. Once simulation is complete, a dataset with input geometry, simulation setup and S-parameter results is automatically assembled and associated with the given EM document for plot, measurement and subsequent extraction, circuit simulation, tuning and optimization. The link supports mesh, current and field visualization data in addition to S-parameters, enabling designers to use the rich set of EM 3D annotations already in the AWR Design Environment platform (see Figure 5).
IC and electronic system companies, particularly those using IC packaging and/or multi-technology modules, face thermal challenges that can derail project schedules. The Cadence Celsius Thermal Solver within AWR software offers a solution for RF device, PCB and module designs supporting electrothermal analysis using model information sourced from AWR Microwave Office software, using existing MMIC design data and geometries such as layout, material properties and power source values from the RF simulation. The solver provides a full IC temperature profile at the relevant resolution of the IC layout, available as a graphically viewable 3D temperature overlay, as well as a temperature-annotated netlist for circuit simulation, as shown in Figure 6.
Thermal analysis provides insight regarding the operating temperatures that can degrade RF performance and threaten device reliability. By using model and power dissipation information obtained from Microwave Office software directly in Celsius Thermal Solver, designers can achieve better accuracy. Additional objects such as a heat sink can be added to the die and exported as a new structure for thermal analysis, which enables designers to investigate heat sinking strategies to best manage heat.
As RF-enabled systems proliferate and adopt heterogeneous technology integration for greater functionality in smaller footprints, design platforms and multi-technology workflows must be interoperable. The AWR Design Environment V16 platform encompasses innovative functionality increasing engineering productivity through seamless cross-platform and multiphysics integration of the AWR platform RF/microwave design IP within the Virtuoso and Allegro design platforms, as well as EM and thermal analysis of complete large-scale designs through Clarity and Celsius solvers.
Engineers working from the IC through the system can better address cross-fabric, multi-technology product development challenges within the comprehensive front-to-back RF workflows offered by Cadence. AWR V16 is further streamlining product development and user productivity, eliminating inefficiency and lost insight when designers spend unproductive time and cycles switching among siloed tools.
Cadence Design Systems, Inc.
San Jose, Calif.