Patents Assigned to Sierra Design Automation, Inc.
  • Patent number: 7191417
    Abstract: A method and apparatus is described which allows efficient optimization of integrated circuit designs. By performing a global analysis of the circuit and identifying bottleneck nodes, optimization focuses on the nodes most likely to generate the highest return on investment and those that have the highest room for improvement. The identification of bottleneck nodes is seamlessly integrated into the timing analysis of the circuit design. Nodes are given a bottleneck number, which represents how important they are in meeting the objective function. By optimizing in order of highest bottleneck number, the optimization process converges quickly and will not get side-tracked by paths that cannot be improved.
    Type: Grant
    Filed: June 4, 2004
    Date of Patent: March 13, 2007
    Assignee: Sierra Design Automation, Inc.
    Inventors: Yufeng Luo, Prasanna Venkat Srinivas, Shankar Krishnamoorthy
  • Patent number: 7092838
    Abstract: A method and apparatus are presented that can analyze the performance of an integrated circuit design at multiple corners, under multiple modes, and for multiple objectives efficiently and simultaneously. The extraction, timing analysis, and optimization functions are integrated into a mechanism that provides a novel problem formulation. A plurality of virtual timing graphs are maintained and updated simultaneously by providing a data structure that can efficiently store operating data for an arbitrary number of conditions at each node. This data structure is populated according to the design, and as optimizations are made, the operating data for all design conditions is updated simultaneously. Timing violations can be reported across all corners and modes. By integrating this multi-corner multi-mode analysis with circuit optimization, a convergent mechanism is provided. In this way, design constraints are evaluated simultaneously for an arbitrary number of design conditions.
    Type: Grant
    Filed: June 4, 2004
    Date of Patent: August 15, 2006
    Assignee: Sierra Design Automation, Inc.
    Inventors: Prasanna Venkat Srinivas, Atul Srinivasan, Shankar Krishnamoorthy