Patents by Inventor Bill R. Tang

Bill R. Tang 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: 7382807
    Abstract: Methods and system are provided for automatic power control of a laser diode, e.g., in a laser driver. In accordance with an embodiment of the present invention, a power controller includes a detector circuit adapted to detect the output of the laser diode and to produce a measured output therefrom. A comparator compares a desired output to the measured output, and produces an error signal therefrom. The error signal is provided to an integrator circuit that produces an integrated error signal. At least one digital-to-analog converter (DAC) uses the integrated error signal to produce a current drive signal that drives the laser diode.
    Type: Grant
    Filed: April 7, 2006
    Date of Patent: June 3, 2008
    Assignee: Elantec Semiconductor, Inc.
    Inventors: Alexander Fairgrieve, D. Stuart Smith, Theodore D. Rees, Bill R. Tang
  • Patent number: 7317674
    Abstract: Optical pick-up units and laser drivers are disclosed, which can be used in various types of information recording/reproducing apparatuses, such as, but not limited to, DVD and CD drives, DVD camcorders, and DVD video recorders. A laser driver integrated circuit (LDIC) includes an automatic power controller, a running optical power controller, and a write strategy generator. The LDIC can be part of a chip-set, to be located on an optical pick-up unit (OPU). The chip-set can also include a power monitor integrated circuit (PMIC) to monitor the laser diode, and a photo-detector integrated circuit (PDIC) to detect light produced by the laser diode. The PMIC and the PDIC each include their own offset, gain and sample-and-hold circuitry.
    Type: Grant
    Filed: March 10, 2004
    Date of Patent: January 8, 2008
    Assignee: Intersil Americas Inc.
    Inventors: Theodore D. Rees, Alexander Fairgrieve, Bill R. Tang, Barry Harvey, Yang Zhao
  • Patent number: 7061951
    Abstract: Methods and system are provided for automatic power control of a laser diode, e.g., in a laser driver. In accordance with an embodiment of the present invention, a power controller includes a detector circuit adapted to detect the output of the laser diode and to produce a measured output therefrom. A comparator compares a desired output to the measured output, and produces an error signal therefrom. The error signal is provided to an integrator circuit that produces an integrated error signal. At least one digital-to-analog converter (DAC) uses the integrated error signal to produce a current drive signal that drives the laser diode.
    Type: Grant
    Filed: July 2, 2003
    Date of Patent: June 13, 2006
    Assignee: Elantec Semiconductor, Inc.
    Inventors: Alexander Fairgrieve, D. Stuart Smith, Theodore D. Rees, Bill R. Tang
  • Publication number: 20040202072
    Abstract: Optical pick-up units and laser drivers are disclosed, which can be used in various types of information recording/reproducing apparatuses, such as, but not limited to, DVD and CD drives, DVD camcorders, and DVD video recorders. A laser driver integrated circuit (LDIC) includes an automatic power controller, a running optical power controller, and a write strategy generator. The LDIC can be part of a chip-set, to be located on an optical pick-up unit (OPU). The chip-set can also include a power monitor integrated circuit (PMIC) to monitor the laser diode, and a photo-detector integrated circuit (PDIC) to detect light produced by the laser diode. The PMIC and the PDIC each include their own offset, gain and sample-and-hold circuitry.
    Type: Application
    Filed: March 10, 2004
    Publication date: October 14, 2004
    Applicant: Elantec Semiconductor, Inc.
    Inventors: Theodore D. Rees, Alexander Fairgrieve, Bill R. Tang, Barry Harvey, Yang Zhao
  • Publication number: 20040120369
    Abstract: Methods and system are provided for automatic power control of a laser diode, e.g., in a laser driver. In accordance with an embodiment of the present invention, a power controller includes a detector circuit adapted to detect the output of the laser diode and to produce a measured output therefrom. A comparator compares a desired output to the measured output, and produces an error signal therefrom. The error signal is provided to an integrator circuit that produces an integrated error signal. At least one digital-to-analog converter (DAC) uses the integrated error signal to produce a current drive signal that drives the laser diode.
    Type: Application
    Filed: July 2, 2003
    Publication date: June 24, 2004
    Applicant: Elantec Semiconductor, Inc.
    Inventors: Alexander Fairgrieve, D. Stuart Smith, Theodore D. Rees, Bill R. Tang