Patents by Inventor Patrick H. Buffet

Patrick H. Buffet 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: 6586828
    Abstract: An electrical bus grid (108) for an application specific integrated circuit (ASIC) chip (102). The bus grid is generally formed by mutually orthogonal wires (28′, 30′) contained within two metal layer (M6′, M7′). The bus grid is located within each of a plurality of contiguous rectangular regions (32′), which are defined by electrical contacts (12′). Due to the regular pattern of the electrical contacts, the bus grids within the contiguous rectangular regions are identical to one another, such that the bus grid forms a repeatable pattern. The widths of the wires in each of the two metal layers vary depending upon the magnitude of the current carried by the corresponding wire. The magnitude of the current in the power bus may be determined by simulation and modeling performed prior to placement of cells (e.g., 18, 20, 22) within the ASIC chip.
    Type: Grant
    Filed: October 17, 2001
    Date of Patent: July 1, 2003
    Assignee: International Business Machines Corporation
    Inventors: Patrick H. Buffet, Yu H. Sun
  • Patent number: 6584596
    Abstract: Disclosed is a method of designing voltage partitions in a solder bump package for a chip, comprising: determining the current requirements of a chip voltage island, the chip voltage island including chip power and signal pads, and creating an equivalent circuit model of the chip voltage island; defining a package voltage island, the package voltage island including power and signal package pins, and creating an equivalent circuit model of the package voltage island; analyzing electrical attributes of a combination of the chip voltage island model and the package voltage island model; and modifying the package voltage island until the electrical attributes are acceptable.
    Type: Grant
    Filed: September 24, 2001
    Date of Patent: June 24, 2003
    Assignee: International Business Machines Corporation
    Inventors: Patrick H. Buffet, Charles S. Chiu, Yu H. Sun
  • Publication number: 20030071343
    Abstract: An electrical bus grid (108) for an application specific integrated circuit (ASIC) chip (102). The bus grid is generally formed by mutually orthogonal wires (28′, 30′) contained within two metal layer (M6′, M7′). The bus grid is located within each of a plurality of contiguous rectangular regions (32′), which are defined by electrical contacts (12′). Due to the regular pattern of the electrical contacts, the bus grids within the contiguous rectangular regions are identical to one another, such that the bus grid forms a repeatable pattern. The widths of the wires in each of the two metal layers vary depending upon the magnitude of the current carried by the corresponding wire. The magnitude of the current in the power bus may be determined by simulation and modeling performed prior to placement of cells (e.g., 18, 20, 22) within the ASIC chip.
    Type: Application
    Filed: October 17, 2001
    Publication date: April 17, 2003
    Applicant: International Business Machines Corporation
    Inventors: Patrick H. Buffet, Yu H. Sun
  • Publication number: 20030061571
    Abstract: Disclosed is a method of designing voltage partitions in a solder bump package for a chip, comprising: determining the current requirements of a chip voltage island, the chip voltage island including chip power and signal pads, and creating an equivalent circuit model of the chip voltage island; defining a package voltage island, the package voltage island including power and signal package pins, and creating an equivalent circuit model of the package voltage island; analyzing electrical attributes of a combination of the chip voltage island model and the package voltage island model; and modifying the package voltage island until the electrical attributes are acceptable.
    Type: Application
    Filed: September 24, 2001
    Publication date: March 27, 2003
    Inventors: Patrick H. Buffet, Charles S. Chiu, Yu H. Sun
  • Patent number: 6538314
    Abstract: A semiconductor device comprising: a global power bus having a first portion for supplying power to a first set of circuits and a second portion for supplying power to a second set of circuits; a local power bus for supplying alternative power to the second set of circuits; and wherein the total of the width of the second portion of the global power bus and of the width of the local power bus does not exceed the width of the first portion of the global power bus.
    Type: Grant
    Filed: March 29, 2002
    Date of Patent: March 25, 2003
    Assignee: International Business Machines Corporation
    Inventors: Patrick H. Buffet, Yu H. Sun
  • Patent number: 6523150
    Abstract: Disclosed is a method of designing voltage partitions in a package for a chip, comprising: determining the current requirements of a chip voltage island comprising a voltage island and power and signal chip pads; computing the voltage drop across power buses in the chip voltage island; assigning additional chip pads to the chip voltage island for use as power pads if the voltage drop is not acceptable; defining a package voltage island, the package voltage island including power and signal package pads; analyzing electrical attributes of a combination of the chip voltage island, the package voltage island and conductive interconnects connecting chip voltage island pads to package voltage island pads; and assigning additional chip pads to the chip voltage island and additional package pads to the package voltage island for use as power pads until the electrical attributes are acceptable.
    Type: Grant
    Filed: September 28, 2001
    Date of Patent: February 18, 2003
    Assignee: International Business Machines Corporation
    Inventors: Patrick H. Buffet, Charles S. Chiu, Yu H. Sun
  • Publication number: 20020196042
    Abstract: A method for improving the signal-to-noise ratio in an IDDQ defect test is disclosed. An integrated circuit is divided into a plurality of areas and each area is provided with and bounded by terminals. An IDDQ defect is activated to generate IDDQ defect current within the integrated circuit. An amount of IDDQ defect current generated within each area is measured at the terminals provided thereto. Based on the IDDQ current measurement on each area, an IDDQ current map is created. By analyzing the IDDQ current map, the presence and location of the defect is determined. Based on the determination, the IDDQ defect is isolated.
    Type: Application
    Filed: June 26, 2001
    Publication date: December 26, 2002
    Inventors: Patrick H. Buffet, Douglas C. Heaberlin, Leah M.P. Pastel, Yu H. Sun
  • Patent number: 6499134
    Abstract: A method for improving the crosstalk and time-of-flight performance for signals in an integrated circuit with respect to the package-related wiring. I/O pads in the package-related wiring of a logic design meeting specified crosstalk and time-of-flight constraints are identified using a software tool. The tool produces a graphical display in which the identified I/O pads are highlighted. The tool enables a user to graphically manipulate the display to assign, i.e., establish an electrical connection, between I/O circuits corresponding to the signals and the highlighted I/O pads.
    Type: Grant
    Filed: July 13, 2000
    Date of Patent: December 24, 2002
    Assignee: International Business Machines Corporation
    Inventors: Patrick H. Buffet, Paul E. Dunn, Joseph Natonio, Robert A. Proctor, Gulsun Yasar
  • Patent number: 6495911
    Abstract: A method and implementing system are described in which a tri-plate chip carrier is effective to significantly reduce electromagnetic signal radiation and provide enhanced noise immunity. The tri-plate structure includes a ground layer, a middle signal conducting layer upon which an integrated circuit is mounted, and a top reference potential layer. The middle layer includes groups of printed circuit conductors extending from the chip to the outer edges of the carrier. The top layer is arranged to have separate electrically isolated conducting areas for VDD and ground reference potential connections. The conducting areas are arranged such that each group of signal conductors in the middle signal layer has a ground potential area above it and a ground potential area below it to provide enhanced signal isolation and reduced electromagnetic radiation.
    Type: Grant
    Filed: August 17, 2000
    Date of Patent: December 17, 2002
    Assignee: International Business Machines Corporation
    Inventors: Patrick H. Buffet, Paul Lee Clouser, Danny Marvin Neal
  • Publication number: 20020186554
    Abstract: A method and implementing system are described in which a tri-plate chip carrier is effective to significantly reduce electromagnetic signal radiation and provide enhanced noise immunity. The tri-plate structure includes a ground layer, a middle signal conducting layer upon which an integrated circuit is mounted, and a top reference potential layer. The middle layer includes groups of printed circuit conductors extending from the chip to the outer edges of the carrier. The top layer is arranged to have separate electrically isolated conducting areas for VDD and ground reference potential connections. The conducting areas are arranged such that each group of signal conductors in the middle signal layer has a ground potential area above it and a ground potential area below it to provide enhanced signal isolation and reduced electromagnetic radiation.
    Type: Application
    Filed: August 12, 2002
    Publication date: December 12, 2002
    Inventors: Patrick H. Buffet, Paul Lee Clouser, Danny Marvin Neal
  • Patent number: 6483720
    Abstract: A method and implementing electronic tri-plate connection system are provided including a nested set of RF Faraday cages within the system with integrated circuit packages containing the core drivers and receivers as the innermost Faraday cage, and additional Faraday cages being implemented at each outward level through card, board, backplane and unit level and into the network level. There is no distinction between power ground, signal ground or shield ground. All grounds throughout the system are at the same level and all package ground levels are interconnected.
    Type: Grant
    Filed: August 17, 2000
    Date of Patent: November 19, 2002
    Assignee: International Business Machines Corporation
    Inventors: Patrick H. Buffet, Paul Lee Clouser, Danny Marvin Neal
  • Patent number: 6477057
    Abstract: A method and implementing computer system are provided in which de-coupling capacitors are used at driver and receiver sources, and defined gaps are created separating power and ground areas on a voltage reference plane of a circuit board. Short-circuit via connections are also provided through one or more vias between spatially separated circuit board layers. Each driver or receiver module includes the driver or receiver along with an associated gap, capacitor and via connections to VDD and ground planes, all included within a defined proximity to effectively block switching energy and/or VDD noise from entering the tri-plate ground-to-ground reference system. In a related exemplary construction, signal lines are placed at predetermined positions between ground planes to provide a tri-plate circuit board structure for transmitting logic signals from a driver to one or more receivers.
    Type: Grant
    Filed: August 17, 2000
    Date of Patent: November 5, 2002
    Assignee: International Business Machines Corporation
    Inventors: Patrick H. Buffet, Paul Lee Clouser, Danny Marvin Neal
  • Publication number: 20020073384
    Abstract: An automated method of selecting differential pairs in an integrated circuit comprising loading the design database for the integrated circuit package, and selecting output parameters for the differential pairs comprises adjacency criteria for the different pairs, time of flight tolerances for the differential pairs, and the redistribution layers and their voltage references. The method then includes comparing the output parameters to the design in the design database, and obtaining a resulting differential pairs list. The differential pair list preferably includes differential signal pairs having electrical characteristics within a predetermined design tolerance range. At least some of the differential signal pairs may comprise individual wires or connectors not physically adjacent one another.
    Type: Application
    Filed: December 11, 2000
    Publication date: June 13, 2002
    Applicant: International Business Machines Corporation
    Inventors: Patrick H. Buffet, Craig Lussier, Joseph Natonio