Patents by Inventor Juerg Fries

Juerg Fries 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: 7479741
    Abstract: The invention relates to a device for lighting at least one light emitting diode to be supplied with predefined minimum forward voltage and maximum current. It comprises: —voltage supply means for supplying voltage to the light emitting diode, —a pulse generator for generating a cyclic pulse signal having predefined on-times and off-times, —a switch, controlled by the pulse generator to be turned on during said on-times to short-circuit the light emitting diode and turned off during said off-times, —an inductive device for increasing the forward voltage over the light emitting diode when the switch is turned off, so that said forward voltage gets higher that the minimum forward voltage and for decreasing said forward voltage when the switch is turned on, so that the current through the light emitting diode remains below the maximum current.
    Type: Grant
    Filed: June 28, 2004
    Date of Patent: January 20, 2009
    Assignee: DSP Group Switzerland AG
    Inventors: Lukas Haener, Juerg Fries
  • Publication number: 20060234779
    Abstract: The invention relates to a device for lighting at least one light emitting diode to be supplied with predefined minimum forward voltage and maximum current. It comprises: voltage supply means for supplying voltage to the light emitting diode, a pulse generator for generating a cyclic pulse signal having predefined on-times and off-times, a switch, controlled by the pulse generator to be turned on during said on-times to short-circuit the light emitting diode and turned off during said off-times, an inductive device for increasing the forward voltage over the light emitting diode when the switch is turned off, so that said forward voltage gets higher thatn the minimum forward voltage and for decreasing said forward voltage when the switch is turned on, so that the current through the light emitting diode remains below the maximum current.
    Type: Application
    Filed: June 28, 2004
    Publication date: October 19, 2006
    Inventors: Lukas Haener, Juerg Fries