Patents Assigned to Mentor Graphics Corporation
  • Patent number: 9729317
    Abstract: This application discloses a computing system implementing tools and mechanisms that can incorporate an optical physical uncloneable function (PUF) device in a circuit design. The optical physical uncloneable function device can generate at least a portion of a key. The tools and mechanisms can interconnect the optical physical uncloneable function device with a security control device in the circuit design, wherein the security control device is configured to initiate a security action when the key matches an expected key in the security controller.
    Type: Grant
    Filed: January 30, 2014
    Date of Patent: August 8, 2017
    Assignee: Mentor Graphics Corporation
    Inventor: Fedor Pikus
  • Patent number: 9727668
    Abstract: Aspects of the present invention are directed to improving the speed of event-driven simulation by manipulating delta delays in a system model to reduce delta cycle executions. The manipulation is performed in a manner that preserves delta cycle accurate timing on selected signals of the system, which may be of interest to a designer. Methods and systems are provided for identifying the signals of interest, and for determining portions of the design that may have delta delays retimed. Preserving the timing on the signals of interest ensures that race conditions and glitches present in the design on the signals of interest are still viewable by the designer. To reduce simulation time, delta delays may be moved from high activity signals to low activity signals, the total number of delta delays may be reduced, or a number of processes executed may be reduced.
    Type: Grant
    Filed: December 31, 2012
    Date of Patent: August 8, 2017
    Assignee: Mentor Graphics Corporation
    Inventors: Sachin Kakkar, John Ries
  • Patent number: 9720859
    Abstract: A system, method and computer program product are provided for conditionally eliminating a memory read request. In use, a memory read request is identified. Additionally, it is determined whether the memory read request is an unnecessary memory read request. Further, the memory read request is conditionally eliminated, based on the determination.
    Type: Grant
    Filed: April 30, 2010
    Date of Patent: August 1, 2017
    Assignee: Mentor Graphics Corporation
    Inventors: Nikhil Tripathi, Venky Ramachandran, Malay Haldar, Sumit Roy, Anmol Mathur, Abhishek Roy, Mohit Kumar
  • Patent number: 9720041
    Abstract: Aspects of the invention relate to scan-based test architecture for interconnects in stacked designs. The disclosed scan-based test architecture comprises a scan chain. Scan cells on the scan chain are configured to receive data from, based on bits of a control signal, outputs of neighboring scan cells or outputs of mixing devices that combine data from through-silicon vias with data from the outputs of the neighboring scan cells. The scan-based test architecture can be used to identify single or multiple defective through-silicon vias.
    Type: Grant
    Filed: February 3, 2014
    Date of Patent: August 1, 2017
    Assignee: Mentor Graphics Corporation
    Inventors: Janusz Rajski, Jerzy Tyszer
  • Patent number: 9720040
    Abstract: Disclosed herein are exemplary methods, apparatus, and systems for performing timing-aware automatic test pattern generation (ATPG) that can be used, for example, to improve the quality of a test set generated for detecting delay defects or holding time defects. In certain embodiments, timing information derived from various sources (e.g. from Standard Delay Format (SDF) files) is integrated into an ATPG tool. The timing information can be used to guide the test generator to detect the faults through certain paths (e.g., paths having a selected length, or range of lengths, such as the longest or shortest paths). To avoid propagating the faults through similar paths repeatedly, a weighted random method can be used to improve the path coverage during test generation. Experimental results show that significant test quality improvement can be achieved when applying embodiments of timing-aware ATPG to industrial designs.
    Type: Grant
    Filed: July 20, 2015
    Date of Patent: August 1, 2017
    Assignee: Mentor Graphics Corporation
    Inventors: Xijiang Lin, Kun-Han Tsai, Mark Kassab, Chen Wang, Janusz Rajski
  • Patent number: 9714981
    Abstract: Aspects of the invention relate to a test-per-clock scheme based on dynamically-partitioned reconfigurable scan chains. Every clock cycle, scan chains configured by a control signal to operate in a shifting-launching mode shift in test stimuli one bit and immediately applies the newly formed test pattern to the circuit-under-test; and scan chains configured by the control signal to operate in a capturing-compacting-shifting mode shift out one bit of previously compacted test response data while compacting remaining bits of the previously compacted test response data with a currently-captured test response to form currently compacted test response data. A large number of scan chains may be configured by the control signal to work in a mission mode. After a predetermined number of clock cycles, a different control signal may be applied to reconfigure and partition the scan chains for applying different test stimuli.
    Type: Grant
    Filed: May 9, 2016
    Date of Patent: July 25, 2017
    Assignee: Mentor Graphics Corporation
    Inventors: Janusz Rajski, Jedrzej Solecki, Jerzy Tyszer, Grzegorz Mrugalski
  • Patent number: 9703916
    Abstract: This application discloses a computing system implementing tools and mechanisms that can incorporate a validation system into a circuit design. The validation system can be configured to monitor at least a portion of an electronic device described in the circuit design. The tools and mechanisms can identify one or more trace signals associated with the electronic device to route to the validation system, and identify one or more trigger signals associated with the electronic device to route to the validation system. The tools and mechanisms can configure the validation system to detect a conditional event corresponding a state of the one or more trigger signals, and to transmit the trace signals associated with the electronic device for debugging in response to the detected conditional event.
    Type: Grant
    Filed: August 29, 2014
    Date of Patent: July 11, 2017
    Assignee: Mentor Graphics Corporation
    Inventors: Rajeev Sehgal, Srinivas Mandavilli, Pradish Mathews, Ajit Singh, Henry Potts
  • Patent number: 9703917
    Abstract: Various aspects of the disclosed techniques relate to techniques for identifying high-impedance nodes in a circuit design. Noise sources are added to nodes of interest in the circuit design. Voltage values at the nodes of interest are then computed in parallel. Based on the voltage values, high impedance nodes in the nodes of interest are identified.
    Type: Grant
    Filed: January 20, 2015
    Date of Patent: July 11, 2017
    Assignee: Mentor Graphics Corporation
    Inventors: Pole Shang Lin, Kuei Shan Wen
  • Patent number: 9703579
    Abstract: Technologies for debugging hardware errors discovered during hardware assisted software verification processes are provided. For example, in one embodiment, a concurrent emulation debug environment including a concurrent emulation system, an emulation trace module and a model state module is provided. The concurrent emulation system includes an emulator and an emulation control station configured to allow simultaneous emulation of multiple electronic designs. The model state module is configured to record the state of the electronic designs during emulation and the emulation trace module is configured to capture trace data associated with the emulation. A backup and capture module is also disclosed that is configured to store the recorded state and the captured trace data for use during a hardware debug process.
    Type: Grant
    Filed: May 1, 2013
    Date of Patent: July 11, 2017
    Assignee: Mentor Graphics Corporation
    Inventors: Krishnamurthy Suresh, Charles W. Selvidge, Sanjay Gupta, Amit Jain
  • Patent number: 9703922
    Abstract: A method of performing a resolution enhancement technique such as OPC on an initial layout description involves fragmenting a polygon that represents a feature to be created into a number of edge fragments. One or more of the edge fragments is assigned an initial simulation site at which the image intensity is calculated. Upon calculation of the image intensity, the position and/or number of initial simulation sites is varied. New calculations are made of the image intensity with the revised placement or number of simulation sites in order to calculate an OPC correction for the edge fragment. In other embodiments, fragmentation of a polygon is adjusted based on the image intensities calculated at the simulation sites. In one embodiment, the image intensity gradient vector calculated at the initial simulation sites is used to adjust the simulation sites and/or fragmentation of the polygon.
    Type: Grant
    Filed: June 6, 2016
    Date of Patent: July 11, 2017
    Assignee: Mentor Graphics Corporation
    Inventors: James Word, Nicolas B. Cobb, Patrick J. LaCour
  • Publication number: 20170185708
    Abstract: Disclosed herein are representative embodiments of methods, systems, and apparatus that can used to control real-time events (e.g., the real-time clock) during the design, simulation, or verification of an embedded system. In one exemplary embodiment disclosed herein, for example, a real-time clock signal is generated and tasks defined by an embedded software application are triggered with the real-time clock signal. In this embodiment, the embedded software application is executed by an embedded processor with a real-time operating system (“RTOS”), and the real-time clock signal is controllable independent of a processor clock signal driving the embedded processor in a manner that allows the real-time clock to have a different time base than the processor clock.
    Type: Application
    Filed: October 3, 2016
    Publication date: June 29, 2017
    Applicant: Mentor Graphics Corporation
    Inventors: Lance S. P. Brooks, Darrell A. Teegarden
  • Patent number: 9689918
    Abstract: Aspects of the invention relate to test access architecture for stacked memory and logic dies. A test access interface for a logic die that is stacked under a memory die is disclosed. The disclosed test access interface can control testing logic core, interconnections with the memory die and with another logic die. The controlling of testing interconnections with the memory die is through a memory boundary scan register controller in the test access interface.
    Type: Grant
    Filed: September 18, 2013
    Date of Patent: June 27, 2017
    Assignee: Mentor Graphics Corporation
    Inventors: Wu-Tung Cheng, Ruifeng Guo, Yu Huang, Liyang Lai, Etienne Racine, Martin Keim, Ronald Press, Jing Ye, Yu Hu
  • Patent number: 9684760
    Abstract: The amount of analysis performed in determining the validity of a property of a digital circuit is measured concurrent with performance of the analysis, and provided as an output when a true/false answer cannot be provided e.g. when stopped due to resource constraints. In some embodiments, a measure of value N indicates that a given property that is being checked will not be violated within a distance N from an initial state from which the analysis started. Therefore, in such embodiments, a measure of value N indicates that the analysis has implicitly or explicitly covered every possible excursion of length N from the initial state, and formally proved that no counter-example is possible within this length N.
    Type: Grant
    Filed: January 12, 2016
    Date of Patent: June 20, 2017
    Assignee: Mentor Graphics Corporation
    Inventors: Jeremy Rutledge Levitt, Christophe Gauthron, Chian-Min Richard Ho, Ping Fai Yeung, Kalyana C. Mulam, Ramesh Sathianathan
  • Patent number: 9679098
    Abstract: This application discloses a computing system to provide test stimulus to an electronic device modeled in a verification environment by the computing system. The computing system can identify transactions performed by the electronic device in the verification environment based, at least in part, on messages exchanged over an interconnect in the electronic device in response to the test stimulus. The computing system can output the transactions from the verification environment and bundle a plurality of the transactions based, at least in part, on messaging relationships defined by a communication protocol for the interconnect. The computing system can utilize the bundles of transactions to determine whether the electronic device functions in accordance with the communication protocol.
    Type: Grant
    Filed: January 29, 2015
    Date of Patent: June 13, 2017
    Assignee: Mentor Graphics Corporation
    Inventors: Andreas Meyer, Adam Erickson, Michael Concannon, Robert Fredieu
  • Patent number: 9679097
    Abstract: This application discloses a computing system to identify an interconnection between portions of a circuit design corresponding to different power domains. The computing system can select a subset of power state tables in the circuit design based, at least in part, on power supplies associated with the interconnection, and generate a composite power state table from the selected subset of power state tables. The computing system can analyze the interconnection to identify electrical characteristics based, at least in part, on power states in the composite power state table, and determine whether a power intent specification in the circuit design can prompt synthesis of interface circuitry capable of implementing the electrical characteristics for the interconnection.
    Type: Grant
    Filed: January 29, 2015
    Date of Patent: June 13, 2017
    Assignee: Mentor Graphics Corporation
    Inventor: Amit Srivastava
  • Patent number: 9673819
    Abstract: This application discloses a system to detect meta-stable glitches in a signal, such as an output of latch or other storage element. The system can include a sampling circuit configured to sample an output of a storage element. The system can include a mono-shot circuit configured to monitor the output of the storage element and generate a pulse when the monitored output of the storage element differs from the sampled output. The system can include a drive circuit configured to generate a glitch signal based, at least in part, on the sampled output, and to output the glitch signal in response to the pulse from the mono-shot circuit. The system can include an error detection circuit configured to receive the sampled output from the sampling circuit and the glitch signal from the drive circuit, and to generate an error signal when the sampled output differs from the glitch signal.
    Type: Grant
    Filed: August 29, 2014
    Date of Patent: June 6, 2017
    Assignee: Mentor Graphics Corporation
    Inventors: Rajeev Sehgal, Srinivas Mandavilli, Pradish Mathews, Ajit Singh, Henry Potts
  • Patent number: 9664739
    Abstract: A method for applying test patterns to scan chains in a circuit-under-test. The method includes providing a compressed test pattern of bits; decompressing the compressed test pattern into a decompressed test pattern of bits as the compressed test pattern is being provided; and applying the decompressed test pattern to scan chains of the circuit-under-test. The actions of providing the compressed test pattern, decompressing the compressed test pattern, and applying the decompressed pattern are performed synchronously at the same or different clock rates, depending on the way in which the decompressed bits are to be generated. A circuit that performs the decompression includes a decompressor such as a linear finite state machine adapted to receive a compressed test pattern of bits. The decompressor decompresses the test pattern into a decompressed test pattern of bits as the compressed test pattern is being received.
    Type: Grant
    Filed: September 14, 2015
    Date of Patent: May 30, 2017
    Assignee: Mentor Graphics Corporation
    Inventors: Janusz Rasjki, Jerzy Tyszer, Mark Kassab, Nilanjan Mukherjee
  • Publication number: 20170147732
    Abstract: Techniques are disclosed for optimizing the pattern density in the circuit layout design of a circuit layer. A layer in circuit design is analyzed to define empty regions that can be filled with fill polygons (referred to hereafter as “fill” regions). Next, a pattern of fill polygons is generated. After the fill polygons have been defined, the layout design for the layer is divided into separate areas or “windows,” and a target density for each window is determined. Once this target density for the window has been determined, the fill polygons required to most closely approach this target density are generated and added to the circuit layout design. This process may be repeated with progressively different (e.g., smaller) fill polygons, until each window meets or exceeds both the specified minimum density and complies with the specified maximum density gradient.
    Type: Application
    Filed: November 22, 2016
    Publication date: May 25, 2017
    Applicant: Mentor Graphics Corporation
    Inventors: Eugene Anikin, Fedor G. Pikus, Laurence Grodd, David A. Abercrombie, John W. Stedman
  • Patent number: 9652581
    Abstract: Aspects of the disclosed technology relate to techniques of combining directed self-assembly lithography and multiple patterning lithography. A coloring/grouping graph is first generated from layout data of a layout design. In the coloring/grouping graph, each coloring edge connects two nodes representing layout features that must be assigned to different masks, and each grouping/coloring edge connects two nodes representing layout features that should either be grouped together for DSA (directed-self-assembly) lithography or be assigned to different masks for multiple patterning lithography. The node groups formed by nodes connected with the coloring edges are colored. Colors of the nodes in one or more of node groups connected by the grouping/coloring edges are adjusted to convert one or more of the grouping/coloring edges into the coloring edges.
    Type: Grant
    Filed: June 19, 2015
    Date of Patent: May 16, 2017
    Assignee: Mentor Graphics Corporation
    Inventors: Fedor Pikus, Juan Andres Torres Robles, Joydeep Mitra
  • Patent number: 9652574
    Abstract: Techniques are disclosed for optimizing the pattern density in the circuit layout design of a circuit layer. A layer in circuit design is analyzed to define empty regions that can be filled with fill polygons (referred to hereafter as “fill” regions). Next, a pattern of fill polygons is generated. After the fill polygons have been defined, the layout design for the layer is divided into separate areas or “windows,” and a target density for each window is determined. Once this target density for the window has been determined, the fill polygons required to most closely approach this target density are generated and added to the circuit layout design. This process may be repeated with progressively different (e.g., smaller) fill polygons, until each window meets or exceeds both the specified minimum density and complies with the specified maximum density gradient.
    Type: Grant
    Filed: April 25, 2011
    Date of Patent: May 16, 2017
    Assignee: Mentor Graphics Corporation
    Inventors: Eugene Anikin, Fedor G. Pikus, Laurence W. Grodd, David A. Abercrombie, John W. Stedman