Abstract: Method and system for designing integrated circuits for yield are described. Integrated circuits are designed for yield by finding worst yield corners based on design, statistical, and environmental variables and optimizing the design in light of the worst yield corners found.
Abstract: A method and system for handling assertion libraries in verification of a design are disclosed. The method and system include structuring and implementing at least one verification component in at least one of the assertion libraries with at least one standard assertion language supported by at least one verification tool, creating an assertion library element for a specific requirement for verification of the design without dependence on the at least one verification tool for the assertion library element, and resolving assertion status. With the disclosed method and system, visualization of assertion status at various levels of design hierarchy and at verification component level may be achieved, and implementing verification techniques may include optimization techniques during and/or after verification.
Abstract: Variations are characterized in feature dimensions of an integrated circuit that is to be fabricated in accordance with a design by a process that produces topographical variation in the integrated circuit, the variations in feature dimension being caused by the topographical variations. The process includes lithography or etch. Predicted characteristics are verified to conform to the design, the characteristics including feature dimensions or electrical characteristics. A process is selected for use in fabricating the integrated circuit based on the relative predicted variations. Chip-level features of a design of an integrated circuit are verified for manufacture within focus limitations of a lithographic tool. Whether a design of a level of an integrated circuit can be lithographically imaged in accordance with the design is predicted, and if it cannot be, the design or processing parameters are adjusted so that it can be.
Abstract: Methods and systems for integrating both models and rules into a verification flow to address both of these issues. Models are employed to perform simulations to provide more accurate verification results. In addition, the lithography simulation results can be used to fine-tune the rules themselves to provide a more realistic check upon circuit designs.
Type:
Grant
Filed:
February 24, 2007
Date of Patent:
April 27, 2010
Assignee:
Cadence Design Systems, Inc.
Inventors:
David White, Roland Ruehl, Mathew Koshy
Abstract: Systems, methodologies and technologies for the analysis and transformation of integrated circuit layouts using situations are disclosed. A method for transforming an integrated circuit (IC) layout includes recognizing shapes within the IC layout, identifying features for each of the shapes and extracting situations for the respective features. Extracted situations can be used to improve optical proximity correction (OPC) of the IC layout. This improved OPC includes extracting the situations, simulating the situations to determine a set of the situations identified for modification based on failing to satisfy a desired OPC tolerance level, modifying the set of situations to improve satisfaction of the desired OPC tolerance level, and reintegrating the modified set of situations into the IC layout. Extracted situations can also be used to improve aerial image simulation of the IC layout.
Type:
Grant
Filed:
December 12, 2006
Date of Patent:
April 27, 2010
Assignee:
Cadence Design Systems, Inc.
Inventors:
Frank E. Gennari, Ya-Chieh Lai, Matthew W. Moskewicz, Michael C. Lam, Gregory R. McIntyre
Abstract: Some embodiments of the invention provide a method for defining wiring directions in a design layout having several wiring layers. The method decomposes a first wiring layer into several non-overlapping regions. It assigns at least two different local preferred wiring directions to at least two of the regions. In some embodiment, the method decomposing the first wiring layer by using the vertices of items in the layout to decompose the layout. In some of these embodiments, the item include macro blocks. The method of some embodiments also identifies several power via arrays on the first wiring layer, and identifies a local preferred wiring direction based on the arrangement of the power via arrays on the first wiring layer.
Type:
Grant
Filed:
December 6, 2004
Date of Patent:
April 27, 2010
Assignee:
Cadence Design Systems, Inc.
Inventors:
Anish Malhotra, Jonathan Frankle, Asmus Hetzel
Abstract: Some aspects provide determination of mutual capacitances among a plurality of floating nets and a plurality of non-floating nets, determination of a self-capacitance of each of the plurality of non-floating nets based on the mutual capacitances, and, for each of the plurality of non-floating nets, association of a ground capacitance with a non-floating net that is substantially equal to a determined self-capacitance of the non-floating net. Aspects may further provide performance of a timing study of a capacitor network including the plurality of non-floating nets using the ground capacitance determined for each of the plurality of non-floating nets.
Abstract: A federated system and methods and mechanisms of implementing and using such a system is disclosed. In some embodiments, one or more mappings are created between a taxonomy view at a node and one or more taxonomies of one or more data sources. The one or more data sources can then be accessed via the taxonomy view. In other embodiments, one or more mappings are created between content from different data sources and content from those data sources are merged using the one or more mappings.
Type:
Grant
Filed:
July 31, 2003
Date of Patent:
April 20, 2010
Assignee:
Cadence Design Systems, Inc.
Inventors:
Steven Sholtis, Terry LeClair, Kenneth Jerome Henderson
Abstract: Systems and methods are provided for annotating software with performance information. The computer code is compiled into assembler code, the assembler code is translated into a simulation model, expressed in assembler-level source code. The simulation model is annotated with information for calculating various performance parameters of the software, such as timing information, or resource usage information. The simulation model is then re-compiled and executed on a simulator, optionally including a hardware simulation model, and the performance information is computed from the simulation.
Type:
Grant
Filed:
May 1, 2001
Date of Patent:
April 20, 2010
Assignee:
Cadence Design Systems, Inc.
Inventors:
Luciano Lavagno, Mihai Lazarescu, Alberto Sangiovanni-Vincentelli, Marcello Lajolo
Abstract: Disclosed is a method, system, and computer program product for implementing model-based layout, placement, and routing. Models are used to guide the placement and routing of polygons on the IC layout. In effect, the parameters that are used for placement and routing are guided by the model data so that the layout can be formed with a high degree of manufacturability from the outset.
Abstract: A method and apparatus for modeling and cross correlation of design predicted criticalities include a feedback loop where information from the manufacturing process is provided to cross correlation engine for optimization of semiconductor manufacturing. The information may include parametric information, functional information, and hot spots determination. The sharing of information allows for design intent to be reflected in manufacturing metrology space; thus, allowing for more intelligent metrology and reduces cycle time.
Type:
Grant
Filed:
December 18, 2006
Date of Patent:
April 6, 2010
Assignee:
Cadence Design Systems, Inc.
Inventors:
Kevin Chan, Emmanuel Drege, Nickhil Jakatdar, Svetlana Litvintseva, Mark A. Miller, Francis Raquel
Abstract: A circuit design system, methodology, and software are disclosed for generating circuit capable of consuming less dynamic power. In particular, the circuit design methodology entails modifying an initial circuit design including a clock network coupled to a plurality of edge-triggered flip-flops to generate a modified circuit design that uses pulsed latches driven by pulse generators in place of at least some of the flip-flops. Since pulsed latches use less dynamic power than edge-triggered flip-flops, the modified circuit may consume less dynamic power. The circuit design methodology may further entail adding delay cells for balancing the clock network to compensate for timing effects caused by the insertion of pulse generators. Additionally, the methodology may further include cloning of forbidden clock paths to make more flip-flops eligible for pulsed latch replacement.
Type:
Grant
Filed:
December 11, 2006
Date of Patent:
April 6, 2010
Assignee:
Cadence Design Systems, Inc.
Inventors:
Hung-Chun Li, Ming-Chyuan Chen, KunMing Ho
Abstract: Methods and apparatus provide for automated synthesis of an integrated circuit whose voltage is varied during operation (also known as dynamic voltage and frequency scaling or DVFS). The automation may include estimating technology parameters from timing libraries, and determining a translation factor that can be used in estimating path delays for an arbitrary voltage from path delays at another voltage. The automation may also include estimating a relative difficulty to synthesize a design for meeting sets of timing constraints specified at different operating voltages and frequencies by assigning one of the constraints a common base value among all the sets, translating the other constraint to maintain equivalency of synthesis difficulty, comparing the resulting equivalent constraints to identify a hardest-to-synthesis constraint set, and using that constraint set as a goal for a first synthesis of the circuit.
Abstract: Some embodiments of the invention provide a method for inserting several fills in an integrated circuit (“IC”) layout. The method identifies a set of potential fills in a region of an IC layout, where the set of potential fills has a first fill size, wherein the first fill size is from a set of fill sizes. The method specifies a halo around each potential fill in the set of potential fills. For each potential fill, the method determines whether the specified halo overlaps with a foreign object in the region of the layout. For each potential fill, the method specifies a legal fill in the region of the IC layout if the specified halo does not overlap with a foreign object in the region of the IC layout. The method inserts at least one legal fill in the region of the IC layout. In some embodiments, the halo is a spacing halo.
Abstract: Method and system for verifying power specifications of a low power design are disclosed. The method includes receiving a register-transfer level (RTL) netlist representation of the low power design, receiving a power specification file for describing power requirements of the low power design and verifying the power specification file in accordance with the RTL netlist representation of the low power design. The method further includes verifying completeness, compatibility, and consistency of power requirements for the low power design.
Type:
Grant
Filed:
October 30, 2006
Date of Patent:
April 6, 2010
Assignee:
Cadence Design Systems, Inc.
Inventors:
Bharat Chandramouli, Huan-Chih Tsai, Manish Pandey, Chih-Chang Lin, Madan M. Das
Abstract: Low power design is a critical concern and metric for integrated circuits. During scan based manufacturing test, electric power dissipation becomes even more critical as the chip may not have been designed to tolerate excessive switching during scan test. Excessive electric power dissipation during scan test can result in excessive voltage variations, reduced noise margins and other signal integrity issues which could invalidate the test or may lead to premature chip failure. Power dissipation during test is minimized by selecting particular values for the unused care-bits in values of the test vectors on a probabilistic basis to minimize switching, while preserving test vector quality.
Type:
Grant
Filed:
February 9, 2007
Date of Patent:
April 6, 2010
Assignee:
Cadence Design Systems, Inc.
Inventors:
Brion L. Keller, Vivek Chickermane, Sandeep Bhatia
Abstract: Disclosed are methods and mechanisms for implementing tessellation-based processing of an integrated circuit design. Tessellation based routing of objects on an integrated circuit layout can be performed by identifying a spacing rule for tessellating at least a portion of the integrated circuit layout, forming one or more plane figures in the tessellation having one or more edges compliant with the spacing rule, the edges of the one or more plane figures forming a contour derived from a shape of a blockage object, and identifying a routing path along at least part of the one or more edges. Packing and pushing of objects may be performed using this approach.
Abstract: Disclosed are a method, a system, and a computer program product for implementing compact manufacturing model during various stages of electronic circuit designs. In some embodiments, the method or the system receives or identifies physics based data. In some embodiments, the method or the system receives or identifies the physics based data for the corresponding manufacturing process by using the golden manufacturing process model. In some embodiments, the method or the system uses the physics based data to fine tune, modify, or adjust the golden manufacturing process model. In some embodiments, the method or the system invokes the just-right module. In some embodiments, the method or the system implements the compact manufacturing model and the correct-by-design module and provides guidelines for the various stages of the electronic circuit design.
Type:
Application
Filed:
September 30, 2008
Publication date:
April 1, 2010
Applicant:
Cadence Design Systems, Inc.
Inventors:
Li J. Song, Srini Doddi, Emmanuel Drege, Nickhil Jakatdar
Abstract: Methods and systems for the integration of models and accurate predictions to score the circuit design, which translates to a more accurate and less complex yield prediction. In the present inventive approach, the computer-implemented methods and systems use at least one processor that is configured for performing at least predicting a physical realization of a layout design based at least in part on one or more model parameters, determining one or more hotspots associated with the layout design, determining a score for each of the one or more hotspots associated with the layout design, and categorizing the one or more hotspots according to at least the score in some embodiments. In some embodiments, the methods or the systems further use at least one processor for the act of determining one or more hotspots by using at least the design intent or the manufacturing information.
Type:
Grant
Filed:
February 24, 2007
Date of Patent:
March 30, 2010
Assignee:
Cadence Design Systems, Inc.
Inventors:
David White, Roland Ruehl, Mathew Koshy
Abstract: A method of modeling an integrated circuit includes: specifying a layout for the integrated circuit, wherein the layout includes a plurality of devices arranged in a plurality of layers and a plurality of connections between the layers; specifying locations for a source point and an observation point for the integrated circuit; determining a plurality of static images for the source point and the observation point; determining a plurality of discrete complex images for the source point and the observation point; determining a Green's-function value for the source point and the observation point by combining the static images and the discrete complex images; and saving at least some values based on the Green's-function value.
Type:
Grant
Filed:
March 16, 2007
Date of Patent:
March 30, 2010
Assignee:
Cadence Design Systems, Inc.
Inventors:
Feng Ling, Ben Song, Vladimir I. Okhmatovski, Enis Aykut Dengi