Patents Assigned to Cadence Design Systems, Inc.
  • Patent number: 9542512
    Abstract: A system and method are provided for maintaining alignment of timing signals of a source synchronous interface between driver and receiver portions of an electronic system in a behavioral model based simulation environment. The system comprises a memory unit, an analysis controller unit coupled to the memory unit, and a timing alignment unit coupled to the analysis controller unit. The timing alignment unit is executable responsive to the analysis controller unit to generate behavioral models for mutually assigned first and second nets which transmit respective timing signals between the driver and receiver portions, and actuates transient simulation on the behavioral models to simulate transmission of the timing signals through the first and second nets. A timing skew between respective transmissions of the timing signals through the first and second nets is measured responsive to the simulated transmission for compensation during a general simulation of the source synchronous interface.
    Type: Grant
    Filed: January 17, 2012
    Date of Patent: January 10, 2017
    Assignee: Cadence Design Systems, Inc.
    Inventors: Feras Al-Hawari, Terry Jernberg, Roger Cleghorn
  • Patent number: 9542084
    Abstract: The present disclosure relates to a computer-implemented method for electronic design automation. The method may include providing, using one or more computing devices, an electronic design. The method may further include receiving an indication that a cursor is hovering over an overlap associated with the electronic design and in response to receiving the indication, computing one or more via parameters, based upon, at least in part, a topology associated with the overlap. The method may also include displaying, at a graphical user interface, a potential via and allowing, at the graphical user interface, adjustments to the one or more via parameters.
    Type: Grant
    Filed: January 21, 2015
    Date of Patent: January 10, 2017
    Assignee: Cadence Design Systems, Inc.
    Inventors: Stephane Colancon, Gerard Tarroux, Mark Nitters, Fabien Campana
  • Patent number: 9529962
    Abstract: The present disclosure relates to a computer-implemented method for use with an electronic design. Embodiments include identifying, using one or more processors, a plurality of sibling nets associated with the electronic design and determining if the plurality of sibling nets have a same input slew rate. If the plurality of sibling nets do not have a same input slew rate, embodiments also include determining a delay calculation (DC) for each of the plurality of sibling nets. If the plurality of sibling nets do have a same input slew rate, embodiments further include sharing a stored DC with the plurality of sibling nets.
    Type: Grant
    Filed: June 5, 2015
    Date of Patent: December 27, 2016
    Assignee: Cadence Design Systems, Inc.
    Inventors: Amit Dhuria, Pradeep Yadav, Manuj Verma, Naresh Kumar, Prashant Sethia
  • Patent number: 9531529
    Abstract: The present disclosure relates to a method and apparatus for detecting clock and data recovery loop saddle-point locking in an electronic circuit. Embodiments may include receiving a signal at a primary clock and data recovery (“CDR”) loop associated with the electronic circuit and processing the signal using at least one of a first order CDR loop and a second order CDR loop included within the primary CDR loop. Embodiments may further include determining whether a fast-phase lock module is required, wherein determining includes determining two transitions in a sampling triplet. If it is determined that the fast-phase lock module is required, embodiments may include providing a trigger signal to the fast-phase lock module. Embodiments may further include receiving the trigger signal at the fast-phase lock module associated with the electronic circuit and performing a fast-phase lock operation on the signal.
    Type: Grant
    Filed: December 16, 2015
    Date of Patent: December 27, 2016
    Assignee: Cadence Design Systems, Inc.
    Inventors: Mathieu Gagnon, Jean-Francois Delage
  • Patent number: 9524366
    Abstract: Methods and systems provide creating and reporting of path annotations and renaming a state node using the path annotations for high level synthesis (HLS). In an embodiment, a method to annotate a state node includes identifying labels and pragmas specified in a high-level language input model for wait statements and function calls, and can also accommodate loops. In an embodiment, a method to display and/or report annotation information for a given state node includes displaying a state node name, an associated path annotation, and/or an associated hierarchical path. In an embodiment, a method to rename a state node based on a user-specified name includes using annotation information to locate a target state node and associating the target state node with the user-specified name or an automatically-created name based on the user-specified name. In an embodiment, a name specified for a state node can persist through successive runs of an HLS tool.
    Type: Grant
    Filed: June 4, 2015
    Date of Patent: December 20, 2016
    Assignee: Cadence Design Systems, Inc.
    Inventors: Yosinori Watanabe, Felice Balarin, Abhinav Tallapally, Walter Johan Ghijsen, Michael J. Meyer, Sherry Solden, David Van Campenhout, Viorica Simion
  • Patent number: 9524364
    Abstract: Methods and systems for creating and implementing improved routing polygon abstracts that can be used to efficiently find areas to route through in electrical designs, where the routing polygon abstracts include at least a horizontal routing polygon abstract, a maximum horizontal routing polygon abstract, a vertical routing polygon abstract, and a maximum vertical routing polygon abstract, that are created through various steps including bloating, shrinking, merging, and extending the objects towards an outer boundary.
    Type: Grant
    Filed: September 23, 2014
    Date of Patent: December 20, 2016
    Assignee: Cadence Design Systems, Inc.
    Inventors: Mark Edward Rossman, Sabra Alexis Wieditz Rossman
  • Patent number: 9524365
    Abstract: A system, method, and computer program product for automatically reducing the number of Monte Carlo simulation samples required to determine if a design yield is above or below a given yield target with a given confidence. Embodiments perform an initial Monte Carlo based performance modeling using an initial set of statistical samples, and estimate the failure probability of each of the remaining statistical samples based on the performance model. Embodiments then simulate each of the remaining statistical samples with a computer-operated Monte Carlo circuit simulation tool in decreasing failure probability order, wherein the sample most likely to fail is simulated first. Progressive comparisons of the simulated yield against a yield target eventually verify the yield at a required confidence level, halting the simulation and triggering tangible output of the comparison results. A potential ten-fold decrease in overall yield verification time without loss of accuracy may result.
    Type: Grant
    Filed: December 23, 2014
    Date of Patent: December 20, 2016
    Assignee: Cadence Design Systems, Inc.
    Inventors: Hongzhou Liu, Wangyang Zhang
  • Patent number: 9519460
    Abstract: A single-instruction multiple-data (SIMD) multiplier-accumulator apparatus and method. A multiplier block with two 16-bit by 32-bit multiplier circuits transform a selectable number of input multipliers and multiplicands into a selected number of products. Each multiplier circuit comprises an array of full adders that generates and sums partial products using carry-save addition. An accumulator block, with additional data width to help prevent overflow, adds the products to a selectable number of input addends and outputs a number of results. Embodiments perform one to four multiplications together, depending on the number of bits (eight, 16, 24, or 32) selected for the input operands. Embodiments output 20-bit, 40-bit, or 80-bit multiply-accumulate results at rates of at least 1.1 GHz. Embodiments support signed inputs, negated multiplication products, and Q-format data. A hybrid sign extension management approach improves performance for 80-bit outputs.
    Type: Grant
    Filed: September 25, 2014
    Date of Patent: December 13, 2016
    Assignee: Cadence Design Systems, Inc.
    Inventors: Aamir A. Farooqui, David Lawrence Heine
  • Patent number: 9519458
    Abstract: A fused-multiply-add system is disclosed. The fused-multiply-add system includes a multiplier to multiply first and second operands and to provide at least one product. The fused-multiply-add system also includes an alignment shifter for aligning a third operand with the at least one product to provide an aligned third operand. The fused-multiply-add system also includes an adder and a subtractor coupled to the multiplier and the alignment shifter for performing two asymmetrical additions in parallel paths. The fused-multiply-add system also includes at least one leading zero counter for counting a number of leading zero bits provided by at least one of the adder and the subtractor to provide at least one normalization shift amount. Finally, the fused-multiply-add system includes a multiplexer coupled to the adder and the subtractor for providing an appropriate output based upon a sign bit.
    Type: Grant
    Filed: April 8, 2014
    Date of Patent: December 13, 2016
    Assignee: Cadence Design Systems, Inc.
    Inventors: David H. C. Chen, William A. Huffman
  • Patent number: 9519732
    Abstract: Some embodiments correlate various manufacturing or design information or data with patterns used to represent electronic designs and provide pertinent pattern-based information to metrology, fabrication, or testing tools to enhance their performances of their intended functions. Some embodiments further utilize cross-design or cross-process analytics to perform various pattern-based analyses on electronic designs. Some embodiments perform squish analysis with a squish pattern library on an electronic design to represent the electronic design with squish patterns by performing pattern matching, pattern decomposition, and pattern classification process.
    Type: Grant
    Filed: March 13, 2013
    Date of Patent: December 13, 2016
    Assignee: Cadence Design Systems, Inc.
    Inventors: Frank E. Gennari, Matthew Moskewicz, Ya-Chieh Lai
  • Patent number: 9513335
    Abstract: Methods and apparatus for decompressing test data using XOR trees for application to scan chains of a design for test (DFT) integrated circuit in a physically efficient construction are disclosed. Moreover, methods and apparatus for compressing test response data from scan chains in a DFT integrated circuit in a physically efficient construction are disclosed. The XOR tree decompression method may comprise splitting signals at each node of the XOR trees according to distribution logic implemented by a set of XOR gates. The XOR tree compression method may comprise combining signals at each node of the XOR trees according to combination logic implemented by a set of XOR gates.
    Type: Grant
    Filed: June 12, 2015
    Date of Patent: December 6, 2016
    Assignee: Cadence Design Systems, Inc.
    Inventors: Steev Wilcox, Brian Edward Foutz, Paul Alexander Cunningham, Vivek Chickermane, Krishna Vijaya Chakravadhanula
  • Patent number: 9507894
    Abstract: An apparatus and method for identifying an optimal harmonic number of a circuit are disclosed. In a simulation of the circuit, a periodic input waveform up to a particular number of periods is applied to the modeled circuit and an output waveform is obtained in response. In response to detection of a steady state response of the output waveform, embodiments simulate the circuit by applying an additional period of the periodic input waveform and obtaining the output waveform corresponding to the additional period of the periodic input waveform. A time domain power value and a frequency domain power value are calculated using the output waveform corresponding to the additional period of the periodic input waveform. Embodiments detect a harmonic of the output waveform corresponding to the additional period of the periodic input waveform at which the time domain power value and the frequency domain power value converge with each other.
    Type: Grant
    Filed: September 28, 2012
    Date of Patent: November 29, 2016
    Assignee: Cadence Design Systems, Inc.
    Inventors: Xiaolue Lai, Xiaohui Wang
  • Patent number: 9501592
    Abstract: Some embodiments provide support for real number modeling in SystemVerilog by defining built-in nettypes with real data type and resolution functions natively in SystemVerilog and allow a simple path for porting Verilog-AMS wreal modeling to SystemVerilog modeling. Some embodiments provide support for incompatible nettypes and for net coercion in SystemVerilog. Some embodiments provide support for SystemVerilog reals net connecting to electrical nets and support for SystemVerilog real signals connecting to Verilog-AMS wreal signals. Some embodiments combine the strengths of Verilog-AMS and SystemVerilog languages to build a solution for value conversion between incompatible nets and an effective way to configure, simulate, or verify mixed-signal designs that are written in SystemVerilog language.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: November 22, 2016
    Assignee: Cadence Design Systems, Inc.
    Inventors: Abhijeet S. Kolpekwar, Aaron M. Spratt, William S. Cranston, Chandrashekar L. Chetput
  • Patent number: 9501598
    Abstract: A system and method for managing analog assertion publication and re-use for analog and mixed-signal circuit designs. A graphical user interface based environment allows circuit designers to create, verify, formalize, and publish an analog assertion for a circuit design for subsequent re-use with another circuit design. Embodiments enable analog assertion handling while simultaneously depicting a circuit design in a schematic and/or layout editor window. Embodiments capture referenced circuit objects and parameterize the assertion for numerical values and connectivity. A designer may publish the assertion and annotate it with descriptive metadata, possibly with other assertions of related functionality, to a library accessible by users of analog design and verification tools.
    Type: Grant
    Filed: September 22, 2014
    Date of Patent: November 22, 2016
    Assignee: Cadence Design Systems, Inc.
    Inventors: Donald J. O'Riordan, Vuk Borich, Keith Dennison
  • Patent number: 9490795
    Abstract: A system and method are provided for selectively coupled parasitic compensation for voltage offset in an electronic circuit. At least one compensation cell is coupled to an input stage for the circuit. The compensation cell includes an isolation node disposed in spaced manner from control and sampling nodes defined by the input stage. The isolation node is configured to form first and second parasitic capacitances respectively with the control and sampling nodes during system operation. An offset switch is coupled to the isolation node and selectively set between first and second switching states. The offset switch selectively either maintains or interrupts a series coupling of the first and second parasitic capacitances between the control and sampling nodes; and, the sampling node is thereby adaptively adjusted in voltage by a predetermined portion of a control signal applied to the control node.
    Type: Grant
    Filed: August 18, 2015
    Date of Patent: November 8, 2016
    Assignee: Cadence Design Systems, Inc.
    Inventors: Eric Naviasky, Ali Ulas Ilhan
  • Patent number: 9477473
    Abstract: This document discusses, among other things, systems and methods to receive an instruction to selectively update a value of one or more selected bits of a first register, to receive the one or more selected bits of the first register to be updated and one or more selected bits of the first register to remain unchanged, and to selectively update the value of the one or more selected bits of the first register using a first write port without receiving the value of the one or more selected bits of the first register. In an example, the value of the one or more selected bits of the first register can be updated without receiving the value of the first register, in certain applications, reducing the number of read ports required to update the value of the first register.
    Type: Grant
    Filed: December 31, 2012
    Date of Patent: October 25, 2016
    Assignee: Cadence Design Systems, Inc.
    Inventor: Fei Sun
  • Patent number: 9477800
    Abstract: The present disclosure relates to a computer-implemented method for electronic design verification. Embodiments may include providing, using one or more processors, an electronic design verification environment having a plurality of randomize calls associated therewith. Embodiments can also include selecting one of the plurality of randomize calls for analysis at a constraint solver engine and iteratively analyzing the selected randomize call using a plurality of constraint solver algorithms. Embodiments can also include automatically determining a most effective constraint solver algorithm for the selected randomize call.
    Type: Grant
    Filed: February 11, 2015
    Date of Patent: October 25, 2016
    Assignee: Cadence Design Systems, Inc.
    Inventors: Daniel Asher Cohen, John LeRoy Pierce, Nir Weiss
  • Patent number: 9477802
    Abstract: An executable circuit design is used to generate waveforms, from which behaviors of the circuit are captured. The behaviors and various combinations thereof can then be saved in a database, along with descriptions and other metadata about them, thereby generating a behavioral index of the circuit design code. Behavioral indexing of circuit designs allows a user to maintain an indexed behavior database, track changes in behaviors as the circuit design's executable description evolves, and figure out how the executable description can be reused in different projects. When applied to digital design development, it facilities the current design and verification effort, as well as design reuse down the line.
    Type: Grant
    Filed: June 9, 2010
    Date of Patent: October 25, 2016
    Assignee: Cadence Design Systems, Inc.
    Inventors: Chung-Wah Norris Ip, Rajeev Kumar Ranjan, Kathryn Drews Kranen, Beth C. Isaksen, Georgia Penido Safe
  • Patent number: 9471094
    Abstract: A chip select signal is trained where the chip select signal is delayed to centrally align its pulses with a positive edge of a memory device's clock cycle. Over repeated iterations, the memory device stops its clock for an interval and a delayed pulse of the chip select signal is generated. The pulse delay is incrementally changed with each iteration. When the delay results in the trailing edge of the delayed pulse aligning with the positive edge of the last cycle before the stoppage interval, the memory device captures the contents of a computer bus, thus detecting a trailing edge delay value. When the delay results in the leading edge of the delayed pulse aligning with the positive edge of the last cycle, the device no longer captures the contents, thus detecting a leading edge delay value. A value between these values is then set as the optimal delay.
    Type: Grant
    Filed: December 30, 2014
    Date of Patent: October 18, 2016
    Assignee: Cadence Design Systems, Inc.
    Inventors: Sandeep Brahmadathan, Jeffrey Scott Earl, Todd Barth
  • Patent number: 9470754
    Abstract: Systems and methods disclosed herein provide for utilizing extra variables in the decompression equation set of an ATPG process for test patterns requiring an excess number of care bits than can be supported efficiently by the current hardware. An elastic interface is utilized between a tester and a decompressor network (e.g., sequential and combinational decompressors) in order to expand the test pattern length and/or the number of input variables. The systems and methods also provide care bits in early scan cycles of the ATPG process for sequential decompressors starting from a fixed state.
    Type: Grant
    Filed: June 11, 2015
    Date of Patent: October 18, 2016
    Assignee: Cadence Design Systems, Inc.
    Inventors: Vivek Chickermane, Krishna Vijaya Chakravadhanula, Brian Edward Foutz, Steev Wilcox, Paul Alexander Cunningham, David George Scott, Louis Christopher Milano, Dale Edward Meehl