Abstract: A method is provided that includes: determining a minimum clock cycle that can be used to propagate a signal about the critical cycle in a circuit design; wherein the critical cycle is a cycle in the design that has a highest proportionality of delay to number of registers; determining for a circuit element in the circuit design, sequential slack associated with the circuit element; wherein the sequential slack represents a minimum delay from among respective maximum delays that can be added to respective structural cycles of which the circuit element is a constituent, based upon the determined limit upon clock cycle duration; using the sequential slack to ascertain sequential optimization based design flexibility throughout multiple stages of a design flow.
Type:
Grant
Filed:
March 21, 2011
Date of Patent:
November 6, 2012
Assignee:
Cadence Design Systems, Inc.
Inventors:
Christoph Albrecht, Philip Chong, Andreas Kuehlmann, Ellen Sentovich, Roberto Passerone
Abstract: Systems, apparatus, and methods of timing analysis with a multi-operating region gate model are disclosed, including modeling a logic gate with a constant direct current (DC) voltage source during a steady state region of operation; in response to a transition from the steady state region of operation, modeling the logic gate with a time-varying voltage dependent current source during a varying current region of operation; and, in response to a transition from the variable current region of operation, modeling the logic gate with a time-invariant voltage dependent current source during an asymptotic region of operation. Instantaneous output current provided by the time varying voltage dependent current source in the VCR region is responsive to time and the instantaneous output voltage of the logic gate. Instantaneous output current provided by the time-invariant voltage dependent current source in the AR region is responsive to the instantaneous output voltage of the logic gate.
Abstract: Disclosed are a method, a system, and a computer program product for implementing hotspot detection, repair, and optimization of an electronic circuit design, which, in some embodiments, defines, identifies criteria for hotspots/metrics or optimization objective function; performs the initial hotspot or metric prediction; identifies correction candidate(s); applies a correction candidate to the electronic circuit design; and determines whether the outcome of applying the correction candidate is acceptable. The method or the system identifies custom correction candidate(s) or custom command(s) and identifies one or more hints for the predicted hotspots or metrics; provides a single architecture to use a first model for hotspot identification/correction and a second model for design check; and provides the capability to apply a correction for a hotspot or metric, evaluate the effectiveness of the correction on the fly, and revert any changes made to the electronic circuit design by the correction.
Type:
Grant
Filed:
June 23, 2009
Date of Patent:
October 30, 2012
Assignee:
Cadence Design Systems, Inc.
Inventors:
Brian Lee, Srinivas Doddi, Ron Pyke, Taber Smith, Emmanuel Drege
Abstract: A computerized method of characterizing a DUV includes executing in a verification environment (VE) a set of verification tests to stimulate the DUV to collect test results from the DUV. The method further includes collecting a set of failure data for the test results; and generating sets of common failures based on clusters of features of interest in the set of failure data. The method further includes generating a set of hints from the common failures; wherein the hints indicate a potential failure mode or a potential root cause failure of the DUV for the test results for the simplified set of tests; and generating a set of debug data from the clusters of features of interest. The method further includes transferring the set of hints and the set of debug data to a user computer for storage, display, and use in an interactive debug session of the DUV.
Abstract: Some embodiments of the invention provide a process for designing and manufacturing an integrated circuit (“IC”). The process selects a wiring configuration and an illumination configuration. The process uses the selected wiring configuration to design an IC layout. The process then uses the selected illumination configuration to manufacture the IC based on the designed IC layout. Some embodiments concurrently select an optimal pair of wiring and illumination configurations. Other embodiments select an illumination configuration based on the selected wiring configuration. Yet other embodiments select a wiring configuration based on the selected illumination configuration. In some embodiments, selecting the illumination configuration entails selecting at least one stepper lens for the IC layout, where the stepper lens illuminates at least one mask for at least one particular layer of the IC layout. In some embodiments, this selection entails selecting a stepper lens for each particular layer of the IC layout.
Abstract: Various embodiments of the present invention provide for automated synthesizing of a circuit wrapper for an integrated circuit element. Specifically, some embodiments of the invention provide computer-aided design (CAD) support for automated circuit wrapper generation, especially circuit test wrappers. Additionally, various embodiments of the invention result in optimally designed and segmented circuit wrappers that are configured for both parallel instruction mode and serial instruction mode.
Type:
Grant
Filed:
December 30, 2009
Date of Patent:
October 23, 2012
Assignee:
Cadence Design Systems, Inc.
Inventors:
Krishna V. Chakravadhanula, Vivek Chickermane
Abstract: A method for modeling state-retention logic includes: specifying a circuit that includes an arrangement of circuit elements, wherein a portion of the circuit is organized into a power domain with a power-domain control for effecting power variations within the power domain, and the power domain includes a state-retention cell that includes a retention element with a retention-element control for saving state-retention-cell values in the retention element during power variations in the power domain; determining one or more pattern faults for detecting defects in state-retention operation of the circuit by associating circuit element values with values for the power-domain control or the retention-element control; and saving one or more values for the one or more pattern faults.
Type:
Grant
Filed:
December 19, 2008
Date of Patent:
October 23, 2012
Assignee:
Cadence Design Systems, Inc.
Inventors:
Krishna Chakravadhanula, Steven L. Gregor, Brion L. Keller, Vivek Chickermane
Abstract: A system, method, and computer program product is disclosed for utilizing dual-value signals, such as hierarchical dual-value signals, for mixed-signal simulation. Such dual-value signals can hold both analog and digital representations of a signal and use the appropriate representations based on which block (analog or digital) for which there is an interaction.
Type:
Grant
Filed:
February 26, 2010
Date of Patent:
October 23, 2012
Assignee:
Cadence Design Systems, Inc.
Inventors:
Chandrashekar L. Chetput, Abhijeet Kolpekwar
Abstract: Method and apparatus for performing static analysis optimization in a design verification system is described. In one example, a description of a verification environment having constrained objects is obtained. The constrained objects are analyzed incrementally to create a data structure of nodes. Each node includes a description of variables transitively connected by constraints. At least one of the nodes reuses a description from at least one other node. The data structure is then used during logic design verification.
Abstract: Disclosed are improved methods, systems, and computer program products for implementing inherited connections for electronic designs. Scoped default connection or global nets are used in inherited connections for default expressions, where the default connection/global net that is applied to a particular portion of the design is scoped by being limited in its application only to certain hierarchical portions of the design.
Abstract: Method, system, and computer program product for saving and restarting discrete event simulations are provided. A discrete event simulation of a scenario is performed via a process executing on a system. The process includes one or more application threads. A checkpoint of the process is created at a point in time when a command to save the discrete event simulation of the scenario is received. The checkpoint includes data elements of the process and the one or more application threads of the process that are stored in components of the system at the point in time. These data elements reflect a state of the process and the one or more application threads of the process at the point in time. The checkpoint is saved to one or more files in the system that are usable to later restart the discrete event simulation of the scenario from the point in time.
Type:
Grant
Filed:
November 5, 2007
Date of Patent:
October 23, 2012
Assignee:
Cadence Design Systems, Inc.
Inventors:
William W. Larue, Jr., Neeti K. Bhatnagar, George F. Frazier, Andrew R. Wilmot
Abstract: Method and apparatus for controlling power in an emulation system are described. In one example, a first interface is configured to receive requirement information for a logic module to be emulated from a host computer system. The requirement information includes at least one of a power requirement or a thermal requirement. A second interface is configured to receive measurement data from sensors in the emulation system. A controller is configured to control at least one of a synchronization system, a power regulation system, or a thermal system in the emulation system in response to the requirement information and the measurement data to reduce power load of the emulation system.
Type:
Grant
Filed:
April 25, 2007
Date of Patent:
October 23, 2012
Assignee:
Cadence Design Systems, Inc.
Inventors:
Mitchell G. Poplack, William F. Beausoleil, Tung-Sun Tung, James Tomassetti
Abstract: The present invention is directed to an improved method, system, and computer program product for accessing and analyzing patterns in the integrated circuit design. The method, system or computer program product includes generating an intelligent signature for a pattern. The derived pattern signature is an intelligent pattern identifier because it retains only essential information about a pattern that corresponds to lithography printable portions of the pattern. Accordingly, one pattern signature can represent a group of design patterns that are equivalents from a lithography perspective.
Abstract: An innovative routing method for an integrated circuit design layout. The layout can include design netlists and library cells. A multiple-level global routing can generate topological wire for each net. An area oriented graph-based detail routing on the design can be performed. A post route optimization after the detail routing can be performed to further improve the routing quality. Some methods can be single threaded all or some of the time, and/or multi-threaded some or all of the time.
Abstract: A method of determining a Negative Bias Temperature Instability (NBTI) effect that combines degradation and recovery for dynamic operation of an integrated circuit (IC) includes: specifying one or more parameters for a degradation model for the IC during a stressed portion of a voltage cycle; specifying one or more parameters for a recovery model for the IC during an unstressed portion of the voltage cycle; determining a degradation value for the voltage cycle from the degradation model; determining a recovery value for the voltage cycle from the recovery model; determining an NBTI value that combines the degradation value and the recovery value for the voltage cycle; and saving at least one value for the NBTI value.
Abstract: An invention is provided for performing flush cache in a non-volatile memory. The invention includes maintaining a plurality of free memory blocks within a non-volatile memory. When a flush cache command is issued, a flush cache map is examined to obtain a memory address of a memory block in the plurality of free memory blocks within the non-volatile memory. The flush cache map includes a plurality of entries, each entry indicating a memory block of the plurality of free memory blocks. Then, a cache block is written to a memory block at the obtained memory address within the non-volatile memory. In this manner, when a flush cache command is received, the flush cache map allows cache blocks to be written to free memory blocks in the non-volatile memory without requiring a non-volatile memory search for free blocks or requiring erasing of memory blocks storing old data.
Abstract: A method of synthesis of multiple implementations of a design is provided comprising: translating a model of the design to a first output model compliant with first constraints; and translating the model of the design to a second output model compliant with second constraints.
Type:
Grant
Filed:
December 31, 2009
Date of Patent:
October 9, 2012
Assignee:
Cadence Design Systems, Inc.
Inventors:
Luciano Lavagno, Alex Kondratyev, Yoshinori Watanabe
Abstract: A system and method is provided for generating a programmably implemented model which emulates a power delivery network serving an integrated circuit (IC) core in an electronic system. The system and method generally comprise measures for establishing a power integrity (PI) topology including models for a voltage regulator module that generates at least one predetermined supply voltage level, and for a conductive power rail portion of the power delivery network (PDN). The system and method further comprise measures for interconnecting to the conductive power rail portion model a first behavioral model indicative of the current consumption characteristics of the IC core, and a second behavioral model indicative of the current consumption of an IO interface buffer driving an output signal of the electronic system.
Type:
Grant
Filed:
December 27, 2010
Date of Patent:
October 9, 2012
Assignee:
Cadence Design Systems, Inc.
Inventors:
Taranjit Singh Kukal, Feras Al-Hawari, Dennis Nagle, Raymond Komow, Jilin Tan
Abstract: A method is provided to evaluate whether one or more test patterns is power safe for use during manufacturing testing of an integrated circuit that includes a nonuniform power grid and that includes a scan chain, the method comprising: assigning respective toggle count thresholds for respective power grid regions of the non-uniform power grid; and determining whether respective numbers of toggles by scan elements of the scan chain within one or more respective power grid regions meet respective toggle count thresholds for the one or more respective regions during at least one scan-shift cycle in the course of scan-in of a test pattern to the scan chain.
Abstract: Systems and methods of semiconductor device fabrication and layout generation are disclosed. An exemplary method includes processes of depositing a layer of a first material and patterning the layer to form an initial pattern, wherein the initial pattern defines critical features of the layout elements using a single exposure; depositing spacer material over the first pattern on the substrate and etching the spacer material such that the spacer material is removed from horizontal surfaces of the substrate and the first pattern but remains adjacent to vertical surfaces of the first pattern; removing the initial pattern from the substrate while leaving the spacer material in a spacer pattern; filling the spacer pattern with final material; and trimming the tilled pattern to remove portions of the final material beyond dimensions of the layout elements.