Patent ID: 7791289
Filing Date: 2010-09-07
Classification: F21K,F21Y,H05B

Abstract:
1. Color adjustable lamp comprising at least two light sources for emitting light having a different color and a lamp driving circuit for receiving a varying supply voltage and for controlling the light sources, wherein the lamp driving circuit is configured to control a color of the light emitted by the lamp on the basis of a shape of the supply voltage and comprises: a ballast control circuit configured to receive the varying supply voltage and to output a lamp control signal for each light source corresponding to the shape of the supply voltage; and a lamp ballast circuit for each of the at least two light sources, each lamp ballast circuit being configured to receive said rectified supply voltage and said corresponding lamp control signal for outputting a light source supply voltage corresponding to said lamp control signal in order to control the light intensity of each light source.