Patents Represented by Attorney Koppel, Patrick, Heyhl & Dawson
  • Patent number: 7764118
    Abstract: A chopper-stabilized amplifier includes a main signal path having first and second chopping circuits at the inputs and outputs of a transconductance amplifier, and an auto-correction feedback loop. The feedback loop includes a transconductance amplifier connected to amplify the chopped output from the main signal path, a third chopping circuit which chops the amplified output, a filter which filters the chopped output to substantially reduce any offset voltage-induced AC component present in the signal being filtered, and a transconductance amplifier which receives the filtered output and produces an output which is coupled back into the main signal path. When properly arranged, the auto-correction feedback loop operates to suppress transconductance amplifier-related offset voltages and offset voltage-induced ripple that might otherwise be present in the amplifier's output.
    Type: Grant
    Filed: February 11, 2009
    Date of Patent: July 27, 2010
    Assignee: Analog Devices, Inc.
    Inventors: Yoshinori Kusuda, Thomas L. Botker
  • Patent number: 7339428
    Abstract: A multiple op amp IC with a single low noise op amp configuration comprises at least two op amp circuits fabricated on a common substrate. The IC can be configured such that the multiple op amps are connected in parallel to form a single op amp having output drive and input-referred noise characteristics which are superior to those of the constituent op amps. The IC can be fabricated with either first or second metallization patterns, with the first pattern providing multiple op amps with separate inputs and outputs, and the second pattern interconnecting the amplifiers to form a single op amp. The second pattern also preferably interconnects at least one set of corresponding high impedance nodes to prevent a difference voltage which might otherwise arise between the nodes due to component mismatches between the multiple op amps.
    Type: Grant
    Filed: May 1, 2006
    Date of Patent: March 4, 2008
    Assignee: Analog Devices, Inc.
    Inventor: Derek F Bowers
  • Patent number: 7217583
    Abstract: Semiconductor light emitting devices are fabricated by placing a suspension including phosphor particles suspended in solvent on at least a portion of a light emitting surface of a semiconductor light emitting element, and evaporating at least some of the solvent to cause the phosphor particles to deposit on at least a portion of the light emitting surface. A coating including phosphor particles is thereby formed on at least a portion of the light emitting surface. Particles other than phosphor also may be coated and solutions wherein particles are dissolved in solvent also may be used.
    Type: Grant
    Filed: September 21, 2004
    Date of Patent: May 15, 2007
    Assignee: Cree, Inc.
    Inventors: Gerald H. Negley, Michael Leung
  • Patent number: 7207693
    Abstract: Light display structures are provided that are simple and comprise few parts so that they can be economically fabricated from various polymers and quickly assembled. They are especially suited for carrying light-emitting elements and lend themselves for realization in a variety of forms such as elongate display structures and sheet-like display structures. They are based upon a plurality of light-emitting elements (e.g., light-emitting diodes) that are coupled between first and second conductors with the addition of other structures (e.g., spacers, wire bonds, tabs) that facilitate the energizing of the light-emitting elements.
    Type: Grant
    Filed: July 5, 2006
    Date of Patent: April 24, 2007
    Assignee: AgiLight, Inc.
    Inventor: William R. Ratcliffe