Patents by Inventor William Kao

William Kao has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8161425
    Abstract: An improved approach for implementing metal fill on an electrical device without causing creating cross-coupling capacitance problems is disclosed. Timing aware metal fill insertion is performed to avoid or minimize cross-capacitance problems on the IC design. A cost may be assigned to different candidate metal fill shapes. The cost is associated with the expected effect upon timing requirements by the metal fill shape, with lower costs corresponding to lower expected impacts upon the timing requirements. To meet density requirements, lower cost metal fill shapes are inserted prior to higher cost metal fill shapes.
    Type: Grant
    Filed: April 19, 2006
    Date of Patent: April 17, 2012
    Assignee: Cadence Design Systems, Inc.
    Inventors: David Noice, Gary Nunn, Inhwan Seo, William Kao, Xiaopeng Dong
  • Patent number: 7865850
    Abstract: A methodology is provided to perform noise analysis in the implementation stage of the design of an integrated circuit, and based upon analysis results, a floorplan may be adjusted or guard rings may be inserted to reduce the impact of digital switching noise upon noise sensitive circuits.
    Type: Grant
    Filed: February 26, 2008
    Date of Patent: January 4, 2011
    Assignee: Cadence Design Systems, Inc.
    Inventors: William Kao, Xiaopeng Dong
  • Patent number: 7661078
    Abstract: Disclosed is an improved method and system for implementing metal fill for an integrated circuit design. When an engineering change order is implemented, the existing dummy metal fill geometries are initially ignored when modifying the layout, even if this results in shorts and/or other DRC violations. Once the ECO changes have been implemented, those violations caused by interaction between the changes and the metal fill are repaired afterwards.
    Type: Grant
    Filed: February 28, 2005
    Date of Patent: February 9, 2010
    Assignee: Cadence Design Systems, Inc.
    Inventors: David C. Noice, William Kao, Inhwan Seo, Xiaopeng Dong, Gary W. Nunn
  • Patent number: 7574685
    Abstract: An improved method, system, and article of manufacture for reducing via failures is described. In one approach, additional vias or via cuts are inserted into an IC device to increase the number of cuts in a given area. The additional vias or via cuts are inserted until a sufficient via density level has been reached.
    Type: Grant
    Filed: April 24, 2007
    Date of Patent: August 11, 2009
    Assignee: Cadence Design Systems, Inc.
    Inventors: Xiaopeng Dong, Inhwan Seo, William Kao, David C. Noice, Gary Nunn
  • Patent number: 7557540
    Abstract: A method and system for measuring the remaining capacity of a battery with open circuit voltage detection is disclosed. The method includes the steps of measuring an open circuit voltage, obtaining an initial capacity based on the open circuit voltage, initializing an accumulation counter with the initial capacity, adjusting the accumulation counter, and obtaining the remaining capacity based on the accumulation counter. The method further includes the step of calibrating the accumulation counter to eliminate accumulated error and offset resulting from the previous operation of adjusting the accumulation counter.
    Type: Grant
    Filed: June 15, 2006
    Date of Patent: July 7, 2009
    Assignee: O2Micro International Ltd.
    Inventors: William Kao, Vincent Hou, Liusheng Liu
  • Publication number: 20070234265
    Abstract: Disclosed is a method, system, and article of manufacture for a one-pass approach for implementing metal-fill for an integrated circuit. Also disclosed is a method, system, and article of manufacture for implementing metal-fill that is coupled to a tie-off connection. An approach that is disclosed comprises a method, system, and article of manufacture for implementing metal-fill having an elongated shape that corresponds to the length of whitespace. Also disclosed is the aspect of implementing metal-fill that matches the routing direction. Yet another disclosure is an implementation of a place & route tool incorporating an integrated metal-fill mechanism.
    Type: Application
    Filed: June 8, 2007
    Publication date: October 4, 2007
    Applicant: CADENCE DESIGN SYSTEMS, INC.
    Inventors: Thanh Vuong, William Kao, David Noice
  • Publication number: 20070170893
    Abstract: A method and system for measuring the remaining capacity of a battery with open circuit voltage detection is disclosed. The method includes the steps of measuring an open circuit voltage, obtaining an initial capacity based on the open circuit voltage, initializing an accumulation counter with the initial capacity, adjusting the accumulation counter, and obtaining the remaining capacity based on the accumulation counter. The method further includes the step of calibrating the accumulation counter to eliminate accumulated error and offset resulting from the previous operation of adjusting the accumulation counter.
    Type: Application
    Filed: June 15, 2006
    Publication date: July 26, 2007
    Inventors: William Kao, Vincent Hou
  • Publication number: 20050044520
    Abstract: Disclosed is a method, system, and article of manufacture for a one-pass approach for implementing metal-fill for an integrated circuit. Also disclosed is a method, system, and article of manufacture for implementing metal-fill that is coupled to a tie-off connection. An approach that is disclosed comprises a method, system, and article of manufacture for implementing metal-fill having an elongated shape that corresponds to the length of whitespace. Also disclosed is the aspect of implementing metal-fill that matches the routing direction. Yet another disclosure is an implementation of a place & route tool incorporating an integrated metal-fill mechanism.
    Type: Application
    Filed: November 19, 2002
    Publication date: February 24, 2005
    Inventors: Thanh Vuong, William Kao, David Noice