Patents by Inventor Andrew Lancaster

Andrew Lancaster 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: 6525524
    Abstract: “A Hall effect sensor or device may be used in a variety of embodiments, such as measuring current within an associated conductor by helping to measure flux density within a gap of a ferromagnetic power meter core, such as in a power meter. A high linearity interface for a Hall effect device is provided for minimizing offset effects without using complicated electronic circuits. Hall effect device may include a substrate, first and second device inputs, and first and second device outputs. The substrate of the Hall effect device may be connected electrically to an output pin of the Hall device to eliminate any effects caused by asymmetry of the voltage appearing in the channel relative to the substrate. The net effect of the high linearity interface is to eliminate any adverse effects to linearity of the system, especially at low magnetic flux levels where the output voltage of the Hall device would be relatively small compared to the offset voltage levels involved.
    Type: Grant
    Filed: September 14, 2001
    Date of Patent: February 25, 2003
    Assignee: Schlumberger Resource Management Services, Inc.
    Inventors: Andrew Lancaster, Farah Kobbi, Michel Gervais, Wendell Goodwin, Karl Heinz-Buethe
  • Publication number: 20030006753
    Abstract: A Hall effect sensor or device may be used in a variety of embodiments, such as measuring current within an associated conductor by helping to measure flux density within a gap of a ferromagnetic power meter core, such as in a power meter. A high linearity interface for a Hall effect device is provided for minimizing offset effects without using complicated electronic circuits. First and second levels of modulation relative to line frequency are used to synchronize Hall effect device input switching circuits and feedback loops for improved elimination of offset signals or noise from the ultimate system output. The substrate of the Hall effect device may be connected electrically to an output pin of the Hall device or to a separate virtual ground to eliminate any effects caused by asymmetry of the voltage appearing in the channel relative to the substrate.
    Type: Application
    Filed: September 6, 2002
    Publication date: January 9, 2003
    Inventors: Andrew Lancaster, Farah Kobbi, Michel Gervais, Wendell Goodwin, Karl Heinz-Buethe
  • Patent number: 6392400
    Abstract: A Hall effect sensor or device may be used in a variety of embodiments, such as measuring current within an associated conductor by helping to measure flux density within a gap of a ferromagnetic power meter core, such as in a power meter. A high linearity interface for a Hall effect device is provided for minimizing offset effects without using complicated electronic circuits. First and second levels of modulation relative to line frequency are used to synchronize Hall effect device input switching circuits and feedback loops for improved elimination of offset signals or noise from the ultimate system output. The substrate of the Hall effect device may be connected electrically to an output pin of the Hall device or to a separate virtual ground to eliminate any effects caused by asymmetry of the voltage appearing in the channel relative to the substrate.
    Type: Grant
    Filed: October 6, 1999
    Date of Patent: May 21, 2002
    Assignee: Schlumberger Resource Management Services
    Inventors: Andrew Lancaster, Farah Kobbi, Michel Gervais, Wendell Goodwin, Karl Heinz-Buethe
  • Publication number: 20020041180
    Abstract: A Hall effect sensor or device may be used in a variety of embodiments, such as measuring current within an associated conductor by helping to measure flux density within a gap of a ferromagnetic power meter core, such as in a power meter. A high linearity interface for a Hall effect device is provided for minimizing offset effects without using complicated electronic circuits. First and second levels of modulation relative to line frequency are used to synchronize Hall effect device input switching circuits and feedback loops for improved elimination of offset signals or noise from the ultimate system output. The substrate of the Hall effect device may be connected electrically to an output pin of the Hall device or to a separate virtual ground to eliminate any effects caused by asymmetry of the voltage appearing in the channel relative to the substrate.
    Type: Application
    Filed: September 14, 2001
    Publication date: April 11, 2002
    Applicant: Schlumberger Resources Management Services Inc.
    Inventors: Andrew Lancaster, Farah Kobbi, Michel Gervais, Wendell Goodwin, Karl Heinz-Buethe