Patents Assigned to The Softube Corporation
  • Wide range dimmable fluorescent lamp ballast system
    Patent number: 5172034
    Abstract: The present invention and its related methods of operation provide a wide range dimmable high frequency lamp ballast system having a resonant circuit associated with each lamp or lamp set for providing a resonant frequency which is substantially higher than the drive frequency at which the lamp or lamp set is driven, and means for automatically selecting a drive frequency to be a submultiple of the resonant frequency of the resonant circuit, the selection of a submultiple being dependent on lamp operating conditions.
    Type: Grant
    Filed: June 10, 1991
    Date of Patent: December 15, 1992
    Assignee: The Softube Corporation
    Inventor: Jesse R. Brinkerhoff