Patents by Inventor Thomas G. Mitchell

Thomas G. Mitchell 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: 10552570
    Abstract: A method, system, and computer product for performing a coupled noise analysis in an integrated circuit (IC) design include copying one or more victim circuit sections of a victim circuit in the IC, generating a blockage circuit section that represents a blockage aggressor circuit in the IC, using the copied one or more victim circuit sections of the victim circuit, determining at least one subcircuit from the blockage circuit section, selecting, for a victim pin on the victim circuit, a power-driven virtual node on the at least one subcircuit, applying a power source to the power-driven virtual node on the at least one subcircuit, calculating a coupled noise at the victim pin contributed by the at least one subcircuit in response to the power source being applied, comparing the coupled noise to a threshold noise level, and altering the IC design when the coupled noise exceeds the threshold noise level.
    Type: Grant
    Filed: September 10, 2018
    Date of Patent: February 4, 2020
    Assignee: International Business Machines Corporation
    Inventors: Tsz-mei Ko, Thomas G. Mitchell, Jason D. Morsey, Steven E. Washburn, Patrick M. Williams
  • Patent number: 10248753
    Abstract: A method, system, and computer product for performing a coupled noise analysis in an integrated circuit (IC) design include copying one or more victim circuit sections of a victim circuit in the IC design, generating a blockage circuit section that represents a blockage aggressor circuit in the IC design, using the copied one or more victim circuit sections of the victim circuit, determining at least one subcircuit from the blockage circuit section, selecting, for a victim pin on the victim circuit, a power-driven virtual node on the at least one subcircuit, applying a power source to the power-driven virtual node on the at least one subcircuit, calculating a coupled noise at the victim pin contributed by the at least one subcircuit in response to the power source being applied, comparing the coupled noise to a threshold noise level, and altering the IC design when the coupled noise exceeds the threshold noise level.
    Type: Grant
    Filed: October 7, 2016
    Date of Patent: April 2, 2019
    Assignee: International Business Machines Corporation
    Inventors: Tsz-mei Ko, Thomas G. Mitchell, Jason D. Morsey, Steven E. Washburn, Patrick M. Williams
  • Publication number: 20190005182
    Abstract: A method, system, and computer product for performing a coupled noise analysis in an integrated circuit (IC) design include copying one or more victim circuit sections of a victim circuit in the IC, generating a blockage circuit section that represents a blockage aggressor circuit in the IC, using the copied one or more victim sections of the victim circuit, determining at least one subcircuit from the blockage circuit section, selecting, for a victim pin on the victim circuit, a power-driven virtual node on the at least one subcircuit, applying a power source to the power-driven virtual node on the at least one subcircuit, calculating a coupled noise at the victim pin contributed by the at least one subcircuit in response to the power source being applied, comparing the coupled noise to a threshold noise level, and altering the IC design when the coupled noise exceeds the threshold noise level.
    Type: Application
    Filed: September 10, 2018
    Publication date: January 3, 2019
    Inventors: Tsz-mei Ko, Thomas G. Mitchell, Jason D. Morsey, Steven E. Washburn, Patrick M. Williams
  • Publication number: 20180101636
    Abstract: A method, system, and computer product for performing a coupled noise analysis in an integrated circuit (IC) design include copying one or more victim circuit sections of a victim circuit in the IC, generating a blockage circuit section that represents a blockage aggressor circuit in the IC, using the copied one or more victim sections of the victim circuit, determining at least one subcircuit from the blockage circuit section, selecting, for a victim pin on the victim circuit, a power-driven virtual node on the at least one subcircuit, applying a power source to the power-driven virtual node on the at least one subcircuit, calculating a coupled noise at the victim pin contributed by the at least one subcircuit in response to the power source being applied, comparing the coupled noise to a threshold noise level, and altering the IC design when the coupled noise exceeds the threshold noise level.
    Type: Application
    Filed: October 7, 2016
    Publication date: April 12, 2018
    Inventors: Tsz-mei Ko, Thomas G. Mitchell, Jason D. Morsey, Steven E. Washburn, Patrick M. Williams
  • Patent number: 7127689
    Abstract: A method is disclosed for preventing circuit failures due to gate oxide leakage, and is used to efficiently check many nets of a circuit on a chip or within a macro to find logical fails due to gate oxide leakage using DC calculations, wherein the gate leakage is treated as a noise source for a static noise analysis of the circuit.
    Type: Grant
    Filed: May 28, 2004
    Date of Patent: October 24, 2006
    Assignee: International Business Machines Corporation
    Inventors: Paul D. Kartschoke, Thomas G. Mitchell, Norman J. Rohrer, Ronald D. Rose
  • Patent number: 6854099
    Abstract: A method and system for performing parasitic extraction, wherein the method comprises calculating the minimum output impedance for a network-connected component comprising a plurality of ports thereby producing a labeled impedance, estimating the minimum output impedance for every net, comparing the labeled impedance with the estimated impedance, and selecting the net which needs to be extracted based on a ratio of values of the labeled impedance and the estimated impedance. The step of calculating comprises labeling every port with a minimum size of port impedance, a resistance from a port to power, and a minimum capacitance of a port-net inside the network connected component. The step of estimating comprises using a geometry of segments of the net comprising a summation of area and perimeter values of all the segments of the net, or calculating a resistance over a length of a total net versus an average width of the net.
    Type: Grant
    Filed: July 1, 2002
    Date of Patent: February 8, 2005
    Assignee: International Business Machines Corporation
    Inventors: Lewis W. Dewey, III, Peter A. Habitz, Thomas G. Mitchell
  • Publication number: 20040003356
    Abstract: A method and system for performing parasitic extraction, wherein the method comprises calculating the minimum output impedance for a network-connected component comprising a plurality of ports thereby producing a labeled impedance, estimating the minimum output impedance for every net, comparing the labeled impedance with the estimated impedance, and selecting the net which needs to be extracted based on a ratio of values of the labeled impedance and the estimated impedance. The step of calculating comprises labeling every port with a minimum size of port impedance, a resistance from a port to power, and a minimum capacitance of a port-net inside the network connected component. The step of estimating comprises using a geometry of segments of the net comprising a summation of area and perimeter values of all the segments of the net, or calculating a resistance over a length of a total net versus an average width of the net.
    Type: Application
    Filed: July 1, 2002
    Publication date: January 1, 2004
    Applicant: International Business Machines Corporation
    Inventors: Lewis W. Dewey, Peter A. Habitz, Thomas G. Mitchell
  • Patent number: 6574782
    Abstract: A structure and method for extracting parasitic capacitance from a multi-layer wiring structure that creates, for each wiring layer in a wiring structure, a wiring density map and measures a plurality of metal segments in a wiring layer to determine an area occupied by the metal segments. The invention calculates an up area capacitance component for each of the metal segments by multiplying the area occupied by the metal segments by a wiring density from the wiring density map of an overlying wiring layer over the metal segments and by a capacitance coefficient of the overlying wiring layer. To calculate the down area capacitance component for each of the metal segments, the invention multiplies the area occupied by the metal segments by a wiring density, from the wiring density map of an underlying wiring layer under the metal segments and by a capacitance coefficient of the underlying wiring layer.
    Type: Grant
    Filed: November 15, 2000
    Date of Patent: June 3, 2003
    Assignee: International Business Machines Corporation
    Inventors: L. William Dewey, III, Peter A. Habitz, Thomas G. Mitchell