Circuit Simulation Patents (Class 703/14)
  • Patent number: 8079000
    Abstract: An equivalency testing system, for formally comparing an RTLM and HLM, is presented. RTLM and HLM are first converted into DFGs RTLMDFG and HLMDFG. RTLMDFG and HLMDFG are then put into timestep form and are called RTLMts and HLMts. A test bench CSts is selected that couples RTLMts and HLMts. The combination of RTLMts[t], HLMts[t] and CSts[t] can have parts designated as datapath. Parts designated as datapath can be subject to a form of equivalence checking that seeks to prove equivalence by a form of inductive theorem proving that propagates symbolic values indicative of whether a node carries the same data content as another node. The theorem proving starts from initial conditions for HLMts[t] determined by partial execution of the HLM. Propagation to a combinational function output can be determined from equivalence relationships between it and another combinational function. Propagation through a multiplexer can produce a conditional symbolic value.
    Type: Grant
    Filed: August 8, 2008
    Date of Patent: December 13, 2011
    Assignee: Synopsys, Inc.
    Inventors: Alfred Koelbl, Carl Preston Pixley
  • Patent number: 8078447
    Abstract: A method of estimating a Miller coefficient for an aggressor network and a victim network coupled by a coupling capacitor includes synthesizing a reduced order system from the aggressor network and the victim network, estimating an active area across the coupling capacitor for an aggressor induced noise signal based on the reduced order system, calculating an estimate of the Miller coefficient based on the active area of the aggressor induced noise signal, and outputting the calculated estimate of the Miller coefficient.
    Type: Grant
    Filed: June 18, 2008
    Date of Patent: December 13, 2011
    Assignee: Oracle America, Inc.
    Inventors: Bogdan Tutuianu, Iris E. Chen, Jiyang Cheng
  • Patent number: 8078928
    Abstract: A system and method for verifying the transmit path of an input/output device such as a network interface circuit. The device's operation with various different input sources (e.g., hosts, input buses) and output sources (e.g., output buses, networks) is modeled in a verification layer that employs multiple queues to simulate receipt of input data, submission to an output port and transmission from the device. Call backs are employed to signal completion of events related to receipt of data at the device and modeling of data processing within the verification layer. As call backs are resolved, corresponding tasks are executed to advance the processing of the data through the verification layer. A device-specific algorithm is executed in the verification layer to predict the ordering of output from the device, and that output is compared to the predicted output by a transmission checker.
    Type: Grant
    Filed: October 12, 2007
    Date of Patent: December 13, 2011
    Assignee: Oracle America, Inc.
    Inventors: Arvind Srinivasan, Rahoul Puri
  • Patent number: 8078446
    Abstract: A linear time-invariant system modeling apparatus comprises a processing resource arranged to receive, when in use, model data constituting to a model of a linear time-invariant system. The model data includes residual value data and scattering data. The processing resource is arranged to perform, when in use, a single value decomposition in respect of the scattering data; the scattering data corresponds, when expressed in matrix form, to a scattering matrix in a state-space representation of the model. The processing resource is also arranged to use, when in use, a result of the single value decomposition in order to generate residual value modification data. The residual value modification data is applied to the residual value data, the residual value data corresponding, when expressed in the matrix form, to a residual value matrix in the state-space representation of the model.
    Type: Grant
    Filed: March 13, 2008
    Date of Patent: December 13, 2011
    Assignee: Agilent Technologies, Inc.
    Inventors: Nobby Stevens, Tom Dhaene
  • Publication number: 20110301932
    Abstract: In one embodiment, a MOSFET model output apparatus is configured to output a MOSFET model for a simulation of a semiconductor circuit. The apparatus includes a shape data input part configured to input shape data of a MOSFET. The apparatus further includes a parameter calculation part configured to calculate a parameter of a parasitic device model to be added to the MOSFET model, using the shape data. The apparatus further includes a MOSFET model output part configured to generate and output the MOSFET model added with the parasitic device model, using the parameter of the parasitic device model. Further, the MOSFET model output part adds different parasitic device models to the MOSFET model in a case where the MOSFET is an N-type MOSFET and in a case where the MOSFET is a P-type MOSFET.
    Type: Application
    Filed: March 4, 2011
    Publication date: December 8, 2011
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Sadayuki YOSHITOMI, Naoki WAKITA, Yuka ITANO, Fumie FUJII
  • Patent number: 8074189
    Abstract: For application to analog, mixed-signal, and custom digital circuits, a system and method to begin with a complex problem description that encompasses many variables from statistical manufacturing, the circuit's environment, and the circuit's design parameters, but then apply techniques to prune the scope of the problem to make it manageable for manual design and more efficient automated design, and finally use that pruned problem for more efficient and effective design.
    Type: Grant
    Filed: February 5, 2009
    Date of Patent: December 6, 2011
    Assignee: Solido Design Automation Inc.
    Inventors: Trent Lorne McConaghy, Jeffrey Dyck, Samer Sallam, Kristopher Breen, Joel Cooper, Jiandong Ge
  • Patent number: 8073671
    Abstract: Simulating an application. A method that may be practiced in a computing environment configured for simulating an application modeled by an application model deployed in a performance scenario of a computing system by deploying service models of the application model to device models modeling devices. The method includes referencing a performance scenario to obtain a transaction being modeled as originating from a first device model. The transaction invokes of a first service model. The first service model specifies hardware actions for simulation. The first service model is referenced to determine the hardware actions for simulation and the next referenced service. The next referenced service specifies hardware actions to be added to the transaction and may specify invocation of other service models. A chain of hardware actions is generated by following the invocation path of the service models. The hardware actions are applied to device models to simulate the transaction.
    Type: Grant
    Filed: March 31, 2006
    Date of Patent: December 6, 2011
    Assignee: Microsoft Corporation
    Inventors: Efstathios Papaefstathiou, John M. Oslake, Jonathan C. Hardwick, Pavel A. Dournov
  • Patent number: 8073820
    Abstract: Various methods and apparatuses are described that provide instrumentation and analysis of an electronic design having one or more bus interconnects. A relational database may have defined tables designed for interconnect analysis of transactions occurring between initiator intellectual property (IP) cores and target IP cores of the electronic design. A query tool may be configured to format input data to be stored in the defined tables, and have application programming interfaces to retrieve data from the defined tables based on performing a query. The query tool executes an algorithm based on the query to provide the interconnect analysis.
    Type: Grant
    Filed: April 7, 2008
    Date of Patent: December 6, 2011
    Assignee: Sonics, Inc.
    Inventors: Krishnan Srinivasan, Chien-Chun Chou, Pascal Chauvet
  • Patent number: 8073668
    Abstract: A test system tests a full system integrated circuit (IC) model that includes a device under test (DUT) IC model and a support IC model. A test manager information handling system (IHS) maps the full system IC model on a hardware accelerator simulator via an interface bus. The hardware accelerator simulator thus emulates the full system IC model. Of all possible fault injection points in the model, the test manager IHS selects a subset of those injection points for fault injection via a statistical sampling method in one embodiment. In response to commands from the test manager IHS, the simulator serially injects faults into the selected fault injection points. The test manager IHS stores results for respective fault injections at the selected injection points. If a machine checkstop or silent data corruption error occurs as a result of an injected fault, the DUT IC model may return to a stored checkpoint and resume operation from the stored checkpoint.
    Type: Grant
    Filed: January 30, 2008
    Date of Patent: December 6, 2011
    Assignee: International Business Machines Corporation
    Inventors: Jeffrey William Kellington, Prabhakar Nandavar Kudva, Naoko Pia Sanda, John Andrew Schumann
  • Patent number: 8069025
    Abstract: According to one embodiment, a logical circuit to be simulated includes a timing network and a specific logical device. The timing network transmits a logical value change of an input signal in correspondence with an elapse of time or clock number increments. The specific logical device receives a timing network output signal that appears at an exit node of the timing network, and a logical value change or a logical value after change of the clock. When predetermined constraint information represents a constraint that a time period or the demanded number of clock cycles needed for a transition of a signal level change to pass through a signal path in the timing network is equal to or smaller than a predetermined numerical value (or equal to or larger than a predetermined numerical value), it is checked if the signal input to the specific logical device violates the predetermined constraint information.
    Type: Grant
    Filed: October 16, 2008
    Date of Patent: November 29, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Kenji Yoshida
  • Patent number: 8069024
    Abstract: In one embodiment, a method comprises partitioning a circuit description into simulateable partitions; sorting the simulateable partitions into classes wherein each simulateable partition included in a given class is equivalent to each other partition in the given class with a specified tolerance; associating a dynamic state machine with each class, wherein states of the dynamic state machine correspond to states reached by at least one simulateable partition in the given class during a simulation; during a simulation of the circuit description, the result of which is stored for user display: responsive to a current state in the dynamic state machine for a first simulateable partition in the given class and further responsive to input stimuli to the first simulateable partition, matching the one or more input stimuli to stimuli associated with a next state edge from the current state; and changing the current state of the first simulateable partition to a second state of the dynamic state machine indicated by
    Type: Grant
    Filed: July 1, 2008
    Date of Patent: November 29, 2011
    Assignee: Cadence Design Systems, Inc.
    Inventor: John F. Croix
  • Patent number: 8069026
    Abstract: Clock gating analysis of a target circuit having a plurality of clock gates, involves the calculation of a clock gate function for each of the clock gates. The clock gate functions indicate an activation state of the clock gates and a combination of output values from sequential circuit elements in the target circuit are substituted into each of the clock gate functions to obtained clock gate function values. Combinations of the clock gate function values form individual clock gating states. Each clock gating state indicates an activation state of each of the local clocks, collectively. A table indicating correlations between the combinations of output values and the clock gating states is generated and from the conversion table, a group that includes all of the clock gating states possible is output.
    Type: Grant
    Filed: December 17, 2007
    Date of Patent: November 29, 2011
    Assignee: Fujitsu Limited
    Inventor: Hiroyuki Higuchi
  • Publication number: 20110288825
    Abstract: As part of the design process it is required to design circuits in order to reduce their power consumption. This is typically done by enabling or disabling flip-flops (FFs), however, such change in the circuit requires certain verification. As sequential clock gating changes the state function it is necessary to perform a sequential equivalence checking (SEC) verification. Applying a full SEC may be runtime consuming and is not scalable for large designs. Methods to reduce the problem of verifying sequential clock gating by reducing the sequential problem into much smaller problem that can be easily solved is therefore shown.
    Type: Application
    Filed: May 24, 2010
    Publication date: November 24, 2011
    Applicant: ATRENTA, INC.
    Inventors: Solaiman RAHIM, Pradeep Kumar NALLA
  • Patent number: 8065130
    Abstract: Programmable architecture for implementing a message processing system using an integrated circuit is described. In an example, configurable logic of an integrated circuit is configured to have a plurality of thread circuits and a memory. Messages are received to the integrated circuit for storage in the memory. The memory is accessed with the plurality of threads to concurrently process a plurality of the messages.
    Type: Grant
    Filed: May 13, 2009
    Date of Patent: November 22, 2011
    Assignee: Xilinx, Inc.
    Inventors: Gordon J. Brebner, Philip B. James-Roxby, Eric R. Keller, Chidamber R. Kulkarni
  • Patent number: 8065512
    Abstract: One embodiment of the present application includes a microcontroller (30) that has an embedded memory (46), a programmable processor (32), and a test interface (34). The memory (46) is accessible through the test interface (34). In response to resetting this microcontroller (30), a counter is started and the test interface (34) is initially set to a disabled state while an initiation program is executed. The test interface (34) is changed to an enabled state—such that access to the embedded memory (46) is permitted through it—when the counter reaches a predefined value unless the microcontroller (30) executes programming code before the predefined value is reached to provide the disabled state during subsequent microcontroller (30) operation.
    Type: Grant
    Filed: August 22, 2006
    Date of Patent: November 22, 2011
    Assignee: NXP B.V.
    Inventors: Ata Khan, Greg Goodhue, Pankaj Shrivastava, Bas Van Der Veer, Rick Varney, Prithvi Nagaraj
  • Patent number: 8065128
    Abstract: Methods and apparatus are provided for efficiently generating designs for testing design automation tools and applications. Randomized and diverse test designs with realistic attributes are automatically generated to allow comprehensive testing of design automation tools such as synthesis, simulation, and place and route tools used to implement designs on electronic devices. Each test design can incorporate a wide range of attributes to allow thorough integration testing of a design automation tool.
    Type: Grant
    Filed: October 23, 2003
    Date of Patent: November 22, 2011
    Assignee: Altera Corporation
    Inventor: John R. Chase
  • Patent number: 8065129
    Abstract: Methods and apparatuses for transient simulation of circuits. One embodiment of the present invention eliminates the inductive branch current variables in terms of node voltage variables to generate a linear equation system with a sparse, symmetric and positive definite matrix, which can be solved efficiently using a pre-conditioned conjugate gradient method. The known vector of the linear equation system includes the contribution from the known inductive branch currents at a previous time instance. In one embodiment of the present invention, a node on a branch to a known voltage, such as ground, and on two resistive branches are identified and eliminated to form the linear equation system with a reduced dimension. In one embodiment of the present invention, multiple time step sizes are selectively used to balance the accuracy in transient simulation and efficiency.
    Type: Grant
    Filed: November 19, 2004
    Date of Patent: November 22, 2011
    Assignee: Synopsys, Inc.
    Inventors: Khalid Rahmat, Ming Huei Young
  • Publication number: 20110282639
    Abstract: A non-quasi-static model of the programming behavior of a floating-gate metal-oxide-semiconductor (MOS) transistor. This model is based on evaluation of a body current, for example determined as a function of voltages applied to the transistor from the circuit environment. The body current is used as an input to a non-quasi-static function on which the modeled gate injection current is based. In one example, the body current is applied to a representation of a series R-C circuit beginning from a time corresponding to the onset of avalanche breakdown, with the voltage across the capacitor serving as a control voltage of a voltage-controlled current source that drives the gate injection current. Integration of the gate injection current over the time interval of the programming pulse provides an estimate of the trapped charge at the floating gate.
    Type: Application
    Filed: January 13, 2011
    Publication date: November 17, 2011
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Borna Obradovic, Keith Green
  • Publication number: 20110282478
    Abstract: A method for generating a layout for a semiconductor device is disclosed. The method includes: receiving a first layout. A portion of the first layout is defined as a first FinFET region. The first FinFET region has first and second sides that each extend approximately in a first direction. The method includes performing a first design rule check (DRC) simulation. The method includes obtaining a first DRC simulation result. The method includes defining a second FinFET region by moving the first side in a second direction perpendicular to the first direction. The method includes performing a second DRC simulation. The method includes obtaining a second DRC simulation result. The method includes selecting one of the first and second FinFET regions based on the first and second DRC simulation results. The method includes generating a second layout using the selected FinFET region.
    Type: Application
    Filed: May 14, 2010
    Publication date: November 17, 2011
    Applicant: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD.
    Inventors: Jeng-Jung Shen, Shao-Ming Yu, Chih-Sheng Chang
  • Patent number: 8060852
    Abstract: A method and systems are provided for screening and rapid evaluation of routed nets in a post-layout circuit environment, such as in the design of printed circuit boards. A portion of nets are selected for determination of associated signal quality factors. Signal channels containing one or more selected nets are then built. A reference input stimulus is propagated along each of the signal channels in a frequency based simulation for generating characteristic responses of the selected nets' signal channels. A signal channel quality factor is obtained for each signal channel based upon its characteristic response. The signal channels and their nets are then comparatively analyzed according to corresponding signal channel quality factors to selectively identify any aberrant nets warranting supplemental evaluation for faults.
    Type: Grant
    Filed: June 23, 2009
    Date of Patent: November 15, 2011
    Assignee: Cadence Design Systems, Inc.
    Inventors: Ambrish Varma, Feras Al-Hawari, Kumar Keshavan
  • Patent number: 8057235
    Abstract: An agent based model system provides simulation of the influence of environmental variables and tendencies in individual and social decision making relating to the formation of coalitions and ethnic groups. The system is based on improved understandings of human decision making under risk, and incorporates recent theoretical developments and computational tools. The system gives analysts the ability to predict the development of coalitions and ethnic groups, as well as the ability to manage the behavior of individuals in such groups. The model results provide confidence intervals for various possible scenarios in a mix of agents' decision rules and distribution of environmental resources. Applications include management of ethnic groups and violent conditions in unstable nations, the tracking of terrorist organizations, development of coalitions and oligopolies in business, and the modeling and interdiction of criminal organizations.
    Type: Grant
    Filed: August 12, 2005
    Date of Patent: November 15, 2011
    Assignee: Purdue Research Foundation
    Inventors: Lawrence Anthony Kuznar, William George Frederick, Robert Louis Sedlmeyer
  • Patent number: 8060355
    Abstract: A method of providing simulation results includes detecting any power net and rail in a circuit netlist. The circuit can be divided into net-partitioned blocks. Using these net-partitioned blocks, a topological analysis can be performed to identify cuttable/un-cuttable devices and synchronization requirements. Then, the circuit can be re-divided into rail-partitioned blocks. Using these rail-partitioned blocks, a sparse solver can identify potential partitions, but eliminate fill-ins as determined by the topological analysis. A cost function can be applied to the potential partitions as well as the identified cuttable/un-cuttable devices to determine final cut points in the circuit and dynamic inputs to the final blocks. Simulation can be performed on the final blocks and simulation results can be generated.
    Type: Grant
    Filed: July 27, 2007
    Date of Patent: November 15, 2011
    Assignee: Synopsys, Inc.
    Inventors: Kevin J. Kerns, Mayukh Bhattacharya, Svetlana Rudnaya, Kiran Gullapalli
  • Publication number: 20110276321
    Abstract: A method and circuit for device specific configuration of an operating voltage is provided. A circuit design is analyzed to determine a maximum gate-level delay for the circuit design. A minimum voltage value corresponding to the maximum gate-level delay is determined along with a default voltage value corresponding to a default gate-level delay. A voltage scaling factor corresponding to the minimum voltage and default voltage values is determined. The circuit design is synthesized such that the synthesized design includes the voltage scaling value. The synthesized design specifies setting an operating voltage to a value of a startup voltage value scaled by the voltage scaling value.
    Type: Application
    Filed: May 5, 2010
    Publication date: November 10, 2011
    Applicant: XILINX, INC.
    Inventors: Tim Tuan, Daniel Chung, Ronald Cline, Andy DeBaets, Matthew H. Klein
  • Patent number: 8055486
    Abstract: A computer program product is provided for power delivery analysis and design for a hierarchical system. The product includes a storage medium, readable by a processing circuit, for storing instructions for execution by the processing circuit for facilitating a method. The method includes building a model corresponding to each element of the hierarchical system, and compiling a repository that contains models corresponding to each element, where the repository includes a net list, a domain list, a component list, a pin list, and a layer list. The method also includes performing optimized gridding for each element, the net list, the domain list, the component list, the pin list, and the layer list; assembling a system model from the models contained in the repository; flattening the system model by converting the system model to a flattened system model that consists entirely of resistors; and running a simulation on the flattened system model.
    Type: Grant
    Filed: August 6, 2008
    Date of Patent: November 8, 2011
    Assignee: International Business Machines Corporation
    Inventors: Daniel Douriet, Anand Haridass, Andreas Huber, Colm B. O'Reilly, Bao Gia-Harvey Truong, Roger D. Weekly
  • Patent number: 8056045
    Abstract: In a circuit simulation system, a storage section is configured to store a circuit data, an analysis condition data and an output data. An initial data setting section reads out the circuit data and the analysis condition data from the storage section and sets an initial data and a convergence condition for a solution calculating process based on the circuit data and the analysis condition data. A processing section generates a circuit equation to each of a voltage variable and a current variable based on the circuit data, and executes the solution calculating process based on the initial data to calculate a solution. A convergence determining section executes a convergence determining process of whether or not the solution meets the convergence condition, on the voltage variable. An output section stores the solution into the output data when it is determined to meet the convergence condition.
    Type: Grant
    Filed: December 17, 2008
    Date of Patent: November 8, 2011
    Assignee: Renesas Electronics Corporation
    Inventor: Makoto Sakuragi
  • Publication number: 20110270598
    Abstract: An integrated circuit design method, system and simulator, wherein the integrated circuit design method includes: determining a region in which power supply noise shall be analyzed; determining current model parameters of the region; determining model parameters of a power supply network model; inputting into a simulator a net list; judging whether or not the region satisfies noise requirements of a chip power supply; and if the region satisfies noise requirements of the chip power supply, determining that the initial area is a minimum area that satisfies the noise requirements of the chip power supply in case the initial number of decoupling capacitors are used in the region.
    Type: Application
    Filed: April 27, 2011
    Publication date: November 3, 2011
    Applicant: International Business Machines Corporation
    Inventors: Xuan Zou, Hai Tao Han, Wei Liu, Ze Gui Pang, Wen Yin
  • Publication number: 20110270597
    Abstract: A mechanism is provided in an integrated circuit simulator for tracking array data contents across three-value read and write operations. The mechanism accounts for write operations with data values and address values having X symbols. The mechanism performs writes to a tree data structure that is used to store the three-valued contents to the array. The simulator includes functionality for updating the array contents for a three-valued write and to read data for a three-valued read. The simulator also includes optimizations for dynamically reducing the size of the data structure when possible in order to save memory in the logic simulator.
    Type: Application
    Filed: April 30, 2010
    Publication date: November 3, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Jason R. Baumgartner, Michael L. Case, Robert L. Kanzelman, Hari Mony
  • Patent number: 8050901
    Abstract: A modeling system for modeling integrated circuits includes a process variation generator for generating a first statistic distribution of a process parameter; a performance parameter distribution generator for generating a second distribution of a performance parameter; a stress generator for generating a third statistic distribution of the performance parameter under a stress condition; and a circuit simulator for receiving data randomly generated based on the first, the second and the third distributions and for generating a statistic distribution of a target performance parameter.
    Type: Grant
    Filed: May 7, 2007
    Date of Patent: November 1, 2011
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventor: Jing-Cheng Lin
  • Patent number: 8051393
    Abstract: In one embodiment, a method for determining a contour simplification of an object for a simulation is provided. An object in a layout of a transistor design to be created with the photolithographic process is determined. The object includes a width and a length in the layout. A contour simulation is performed to determine a generated contour object. The contour simulation simulates parametric variation factors that may occur in the photolithographic process. An adjusted width and adjusted length of the object is then determined based on the generated contour object. The adjusted width and the adjusted length are usable to determine a parametric model for simulation of the object. For example, a layout versus schematic (LVS) tool may back-annotate the layout. Then, a SPICE simulation may use the output of the LVS tool to verify the electrical behavior of the transistor using the adjusted width and adjusted length.
    Type: Grant
    Filed: July 14, 2009
    Date of Patent: November 1, 2011
    Assignee: Mentor Graphics Corporation
    Inventors: Jean-Marie Brunet, William S. Graupp
  • Patent number: 8050904
    Abstract: A method, data processing system, and computer program product are provided for performing time-based symbolic simulation. A delay-aware representation of a circuit is created that includes a plurality of circuit nodes. The data-aware representation is simulated. In particular, the simulator simulates transitions from a first set of circuit nodes to a second set of circuit nodes selected from the plurality of circuit nodes, the simulating based on executing a first set of simulation events. A second set of simulation events is then generated in response to executing the first set of simulation events. During the simulation, a time is computed for each of the transitions. An an event scheduling diagram is constructed during simulation. The event scheduling diagram depicts the transitions and the times of the transitions.
    Type: Grant
    Filed: September 15, 2006
    Date of Patent: November 1, 2011
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Jayanta Bhadra, Magdy S. Abadir, Ping Gao, Timothy David McDougall
  • Patent number: 8050903
    Abstract: Apparatus for storing all logic simulation signal values generated by a logic simulator during a simulation run is provided. The apparatus includes a runtime array for storing a plurality of signal values for each time instance in a predetermined time period, and a checkpoint cache for selectively storing the plurality of signal values stored in the runtime array at selected time instances. A hyper-checkpoint array is further provided to checkpoint the signal values in the checkpoint cache. In addition, the time instances and values of memory writes are also checkpointed. A user may retrieve the value of any signal values generated during the simulation run and may additionally rewind the simulator to a user-specified time in the simulation run.
    Type: Grant
    Filed: August 26, 1993
    Date of Patent: November 1, 2011
    Assignee: Texas Instruments Incorporated
    Inventors: Patrick W. Bosshart, Derek James Smith, Daniel Charles Pickens, Douglas J. Matzke
  • Patent number: 8050902
    Abstract: At a simulation client, a design is simulated utilizing a hardware description language (HDL) simulation model by stimulating the HDL simulation model with a testcase. The HDL simulation model includes instrumentation not forming a portion of the design that includes a plurality of count event counters that count occurrences of count events in the design during stimulation by the testcase. At multiple intervals during stimulation of the HDL simulation model by the testcase, the simulation client records count values of the plurality of count event counters. The simulation client determines, for each of the multiple intervals, a temporal statistic regarding the count values of the plurality of count event counters and outputs a report containing temporal statistics for the multiple intervals.
    Type: Grant
    Filed: October 31, 2007
    Date of Patent: November 1, 2011
    Assignee: International Business Machines Corporation
    Inventors: Michael L. Behm, Carol I. Gabele, Derek E. Williams
  • Publication number: 20110264422
    Abstract: A method of analyzing electrical stability of an active circuit splits a frequency response of an electrical or electronic circuit according to sub-bands (134, 136, 138) and in each sub-band (134, 136, 138) implements a step of determining an identification transfer function adapted for a stability analysis. The step of determining the transfer function is automatic and executed in the form of an identification loop, parameterized according to a current order of transfer function, and stopped when the norm of a phase error function for the error between the phase (222, 224, 226) of the current identified transfer function and that of the frequency response has exceeded a predetermined phase error threshold value.
    Type: Application
    Filed: October 27, 2009
    Publication date: October 27, 2011
    Inventors: Alain Mallet, Aitziber Anakabe Iturriaga, Geoffroy Soubercaze-Pun, Juan Maria Collantes Metola
  • Patent number: 8046201
    Abstract: A method of creating and using a hardware independent communication interface block for block diagram environments is disclosed. The communication interface block includes user-selectable parameters controlling how a system being modeled by a block diagram communicates with image and data acquisition devices and control instruments or other electronic device interfaced with an external system. Based on the user selected parameters, the communication interface block calls an appropriate constructor to create an instrument object or acquisition device object which is used to enable communication with the control instrument or acquisition device respectively. The instrument object/acquisition device object calls a software driver appropriate for the hardware interface of the control instrument/acquisition device. The use of a common interface block provides scalability and ease of use to the block diagram environment when interacting with control instruments and acquisition devices.
    Type: Grant
    Filed: May 14, 2004
    Date of Patent: October 25, 2011
    Inventors: Melissa J. Pike, Loren Dean, Christian Portal, Robert O. Aberg, Patrick L. Edson, Thomas Gaudette, Jennifer R. Lymneos
  • Patent number: 8046206
    Abstract: A method of defining a configuration of hardware resources, using a subgraph isomorphism process. The method executes a subgraph isomorphism process to discover possible resources in a hardware resource space that are suitable to implement a function. The hardware resource space may be defined by a target graph and the function may be defined by a subgraph. Next, the target graph is annotated to establish configuration settings for selected resources of the possible resources. The configuration settings may be established based on the subgraph mapping to the target graph. The target graph may also be annotated to specify parameters for the selected resources. This annotation may be performed in response to receiving parameters for the function.
    Type: Grant
    Filed: September 27, 2002
    Date of Patent: October 25, 2011
    Assignee: Cypress Semiconductor Corporation
    Inventors: Frederick R. Hood, III, Kenneth Y. Ogami
  • Publication number: 20110257943
    Abstract: When modeling a circuit, transient analysis is an important part of the analysis. However, for transient analyses, device model evaluating can consume a considerable amount of time, when using conventional simulators. Here, a simulator is provided that allows for detection of latency on a node-by-node basis, as opposed to a device-by-device basis with conventional simulators. Using this type of analysis can greatly reduce the time of an analysis, which affects both the cost of a product and its time to market.
    Type: Application
    Filed: April 16, 2010
    Publication date: October 20, 2011
    Applicant: Texas Instruments Incorporated
    Inventor: Gang Peter Fang
  • Publication number: 20110257954
    Abstract: In an embodiment, an aging analysis tool may be configured to identify transistors that are expected to experience aging effects according to worst case stress vectors and/or designer identified worst case conditions. The aging analysis tool may modify a representation of the circuit (e.g. a netlist), replacing the identified transistors with aged transistors (e.g. by modifying parameters of the transistors in the netlist). The aging analysis tool may process the modified netlist over a range of conditions at which the circuit is expected to operate, to ensure that the design meets specifications after aging. The process may be repeated until the aged design meets specifications (with circuit modifications made by the designer to improve the design).
    Type: Application
    Filed: April 19, 2010
    Publication date: October 20, 2011
    Inventors: Apurva H. Soni, Anonietta Oliva, Edgardo F. Klass, Matthew J.T. Page, James E. Burnette, II
  • Publication number: 20110257953
    Abstract: A link simulation tool for simulating high-speed communications link systems is provided. Communications links may include link subsystems such as transmit (TX) circuitry, receive (TX) circuitry, oscillator circuits that provide reference clock signals to the TX and RX circuitry, and channels that link the TX and RX circuitry. The link simulation tool may model each of the subsystems using behavioral models. The behavioral models may include characteristic functions such as transfer functions, probability density functions, and eye characteristics. The link simulation tool may have a link analysis engine that is capable of performing two-dimensional (two-variable) convolution operations and in applying dual-domain (frequency-time) transformations on the characteristic functions provided by the behavioral models to simulate the performance of the link system.
    Type: Application
    Filed: April 19, 2010
    Publication date: October 20, 2011
    Inventors: Peng Li, Masashi Shimanouchi, Thungoc M. Tran, Sergey Shumarayev
  • Patent number: 8041553
    Abstract: A computer-based system for testing a circuit design for implementation within an integrated circuit device can include a design application (205) providing simulation instructions for testing a circuit design and a simulation driver (225) receiving the simulation instructions and translating the simulation instructions into control protocol instructions specifying operations of an integrated circuit control protocol. The system can include a simulation environment (240). The simulation environment can include a communication module (245) communicating with the simulation driver, a simulation cable driver (250) receiving the control protocol instructions from the simulation driver via the communication module, and a control module (255). The simulation cable driver further can translate the control protocol instructions into signaling information corresponding to the integrated circuit control protocol.
    Type: Grant
    Filed: February 29, 2008
    Date of Patent: October 18, 2011
    Assignee: Xilinx, Inc.
    Inventors: Adrian M. Hernandez, Michael E. Darnall
  • Patent number: 8041552
    Abstract: A method of modeling the output drivers in an integrated circuit, for example a serializer/deserializer circuit, is provided. In accordance with embodiments of the invention, at least one parameter of the circuit is physically measured and a behavioral model utilizing that parameter is constructed. The behavioral model can then be utilized to predict the behavior of the integrated circuit output drivers.
    Type: Grant
    Filed: April 10, 2007
    Date of Patent: October 18, 2011
    Assignee: Intergrated Device Technology, Inc.
    Inventor: David J. Pilling
  • Patent number: 8041551
    Abstract: An algorithm and architecture are disclosed for performing multi-argument associative operations. The algorithm and architecture can be used to schedule operations on multiple facilities for computations or can be used in the development of a model in a modeling environment. The algorithm and architecture resulting from the algorithm use the latency of the components that are used to process the associative operations. The algorithm minimizes the number of components necessary to produce an output of multi-argument associative operations and also can minimize the number of inputs each component receives.
    Type: Grant
    Filed: December 18, 2009
    Date of Patent: October 18, 2011
    Assignee: The MathWorks, Inc.
    Inventors: Alireza Pakyari, Brian K. Ogilvie
  • Patent number: 8037446
    Abstract: Methods are disclosed for defining evaluation points for use in optical proximity correction of a rectangular target geometry. A method for defining evaluation points for use in optical proximity correction of a rectangular target geometry may comprise predicting a contour of an image to be produced in an optical proximity correction simulation of a target geometry. The target geometry may comprise a plurality of line segments, each line segment of the plurality having one evaluation point defined thereon. The method may further comprise shifting at least one evaluation point to an associated point on the predicted contour of the image.
    Type: Grant
    Filed: July 16, 2008
    Date of Patent: October 11, 2011
    Assignee: Micron Technology, Inc.
    Inventors: John R. C. Futrell, Ezequiel Vidal Russell, William A. Stanton
  • Publication number: 20110246169
    Abstract: A semiconductor circuit designing supporting system, includes: a storage unit in which two models of a first model and a second model are stored as device models a semiconductor device; and an operation unit. The operating unit includes: a characteristic variation calculating section configured to calculate a variation of a device characteristic when process parameters are varied by using the first model; and an analyzing section configured to normalize based on the variation, an error between a device characteristic calculated by using the second model and actual measurement data and to analyze the second model by using the normalized error.
    Type: Application
    Filed: March 30, 2011
    Publication date: October 6, 2011
    Inventor: Hironori SAKAMOTO
  • Patent number: 8032338
    Abstract: A computer-implemented method for the design of a power supply is disclosed. Multiple lists of power supply design variables are provided. The method includes simulating a first power supply design in response to power supply design variables selected from these multiple lists of variables. The method then calculates a score of the first power supply design and determines whether the score is better than the score of any power supply design included in a set of power supply designs. If so, the method replaces a power supply design having a worst score from the set of power supply designs with the first power supply design.
    Type: Grant
    Filed: June 13, 2008
    Date of Patent: October 4, 2011
    Assignee: Power Integrations, Inc.
    Inventors: Arkady Akselrod, Sameer Kelkar, Timothy E. W. Starr
  • Patent number: 8032349
    Abstract: Disclosed herein are embodiments of an automated, fast and efficient method of generating a customized compact model that represents a semiconductor device at the chip, wafer or multi-wafer level in a specific manufacturing environment. Specifically, measurement data is collected from a specific manufacturing environment and sorted by channel lengths. Then, an optimizer is used to generate customized modeling parameters based on the measurement data. The optimization processes is a multi-step process. First, a first set of modeling parameters is generated based on measurement data associated with a long channel length. Second, a second set of modeling parameters is generated based on the first set and on measurement data associated with a short channel length. Finally, the customized modeling parameters are generated based on both the first set and the second set. The customized modeling parameters are used to generate a customized compact device model representative of the specific manufacturing environment.
    Type: Grant
    Filed: January 25, 2007
    Date of Patent: October 4, 2011
    Assignee: International Business Machines Corporation
    Inventors: Sim Y. Loo, Steven G. Lovejoy, Myung-Hee Na, Edward J. Nowak, Scott K. Springer
  • Patent number: 8032350
    Abstract: Methods for generating realistic waveform vectors with controllable amplitude noise and timing jitter, simulatable in a computer-based simulation environment are disclosed. In one implementation, a transition vector is created from a sequence of bits having a rise time and a fall time, in which the transition vector comprises voltage values at timings corresponding to midpoints of transitions in the bit sequence. A jittered transition vector is created from the transition vector, in which the timing of the transitions in the jittered transition vector include timing jitter. An upscaled jittered transition vector is then formed having additional points, in which at least some of the additional points comprise corners of the sequence of bits. The voltages of the additional points are set by the sequence of bits, and the timing of the corners are set in accordance with the rise time and the fall time.
    Type: Grant
    Filed: October 29, 2007
    Date of Patent: October 4, 2011
    Assignee: Micron Technology, Inc.
    Inventor: Timothy M. Hollis
  • Patent number: 8032342
    Abstract: A method for generating a linear piecewise representation of a driver output current signal includes segmenting the driver output current signal such that an integral of each segment matches an actual voltage change in corresponding portion of an associated output voltage signal (within a desired tolerance). The beginning and ending current/time values for each segment can then be compiled into the piecewise linear representation of the driver output current signal. A method for generating a model driver output current signal includes conformally mapping first and second sets of precharacterization output current data based on a weighted average of the indexing parameter (e.g., input slew or output capacitance) values for the model driver output signal and the first and second sets of precharacterization data.
    Type: Grant
    Filed: April 29, 2009
    Date of Patent: October 4, 2011
    Assignee: Synopsys, Inc.
    Inventor: Harold J. Levy
  • Publication number: 20110239182
    Abstract: A set of pareto optimal solutions that are non-dominated solutions in a solution specification space for respective items in requirement specification is extracted with a combination of a circuit configuration including a specific function and a process constraint condition. Furthermore, pareto optimal solutions are extracted for all combinations of the circuit configuration and the process constraint condition, and pareto optimal solutions are extracted for the respective process constraint conditions. When such extracted data is distributed to designers, it is possible to reduce time to generate the pareto optimal solutions, and the designers can design the optimum circuit having a desired function by using such extracted data.
    Type: Application
    Filed: September 23, 2010
    Publication date: September 29, 2011
    Applicant: FUJITSU LIMITED
    Inventors: Izumi Nitta, Yu Liu
  • Publication number: 20110239002
    Abstract: Differential uncloneable variability-based cryptography techniques are provided. The differential cryptography includes a hardware based public physically uncloneable function (PPUF) to perform the cryptography. The PPUF includes a first physically uncloneable function (PUF) and a second physically uncloneable function. An arbiter determines the output of the circuit using the outputs of the first and second PUFs. Cryptography can be performed by simulating the PPUF with selected input. The output of the simulation, along with timing information about a set of inputs from where the corresponding input is randomly selected for simulation, is used by the communicating party that has the integrated circuit with the PPUF to search for an input that produces the output. The input can be configured to be the secret key or a part of the secret key.
    Type: Application
    Filed: March 25, 2010
    Publication date: September 29, 2011
    Applicant: EMPIRE TECHNOLOGY DEVELOPMENT LLC
    Inventors: Nathan Zachary BECKMANN, Miodrag POTKONJAK
  • Patent number: 8027829
    Abstract: A system and method for integrated circuit emulation. One embodiment provides a system for in-circuit emulation of an integrated circuit device with program-controlled components. The system includes an integrated circuit device with program-controlled components used in a system for normal operation. The integrated circuit device having at least one program-controlled emulation unit emulating at least one of the program-controlled components of the integrated circuit device, and at least one statistics memory for storing statistical data of the program-controlled emulation unit during emulation.
    Type: Grant
    Filed: February 28, 2008
    Date of Patent: September 27, 2011
    Assignee: Infineon Technologies AG
    Inventors: Albrecht Mayer, Harry Siebert