Patents by Inventor Hubie Notohamiprodjo

Hubie Notohamiprodjo 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).

  • Parallel resonant ballast with boost
    Patent number: 5559405
    Abstract: A ballast for operating gas discharge lamps has a voltage boost, a half-bridge inverter and a parallel resonant circuit. An inverter control inhibits operation of the inverter when power is initially applied to the ballast.
    Type: Grant
    Filed: September 14, 1995
    Date of Patent: September 24, 1996
    Assignee: Motorola, Inc.
    Inventor: Hubie Notohamiprodjo
  • Dimming circuit for powering gas discharge lamps
    Patent number: 5457360
    Abstract: A ballast circuit uses an optocoupler to provide electrical isolation of the dimming control from the remainder of the ballast. The optocoupler is operated in the linear range to provide continuous dimming of the lamps. The circuit further uses a combination of diodes and a diode bridge to steer current from the current sensor during lamp out conditions so that the inverter will maintain operation at a low frequency, thereby maximizing the output voltage. A clamp winding is used to insure that the voltage does not exceed the DC rail voltage.
    Type: Grant
    Filed: March 10, 1994
    Date of Patent: October 10, 1995
    Assignee: Motorola, Inc.
    Inventors: Hubie Notohamiprodjo, John M. Wong, Dennis L. Stephens