Patents by Inventor Clifford Ortmeyer

Clifford Ortmeyer 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).

  • Method and circuit for driving a low voltage light emitting diode
    Publication number: 20060043911
    Abstract: In a method for producing a control signal for regulating a drive current for driving an LED, a current through the LED is sensed, wherein the LED is driven by a power converter output, and wherein an output voltage of the power converter is proportionately controlled by a control signal. Next, a power supply voltage is sensed. The control signal is produced for the power converter, wherein the control signal is proportional to a difference between a reference voltage and the current through the LED. The control signal is then offset in response to the power supply voltage to reduce the current through the LED as the power supply voltage drops.
    Type: Application
    Filed: August 31, 2004
    Publication date: March 2, 2006
    Inventors: Jianwen Shao, Clifford Ortmeyer