Patent Number: 7,612,504

Title: Lamp with integral voltage converter having phase-controlled dimming circuit for reducing RMS load voltage

Abstract: An incandescent lamp includes a lamp voltage conversion circuit within the lamp and connected to a lamp terminal, where the voltage conversion circuit converts a first line voltage at the lamp terminal to a second RMS load voltage usable by a light emitting element of the lamp. The voltage conversion circuit includes a triac phase-controlled dimming circuit, which in turn includes a voltage controlled resistor that varies a resistance in the phase-controlled dimming circuit as the first voltage varies so as to maintain the second voltage substantially constant. The voltage conversion circuit may be an integrated circuit that is in the lamp base and connected between the lamp terminal and the light emitting element.

Inventors: Ballenger; Matthew B. (Lexington, KY), Kendrick; George B. (Lexington, KY)

Assignee: OSRAM SYLVANIA Inc.

International Classification: H05B 37/00 (20060101)

Expiration Date: 1/03/02017