Patent ID: 7518319
Filing Date: 2009-04-14
Classification: H05B,Y02B

Abstract:
1. A lighting device comprising: at least two lines connected in parallel, at least one constant voltage source for applying a constant voltage to the lines, an ON/OFF controller, a current detector for measuring a value of current flowing in the lines, and a bypass switch connected in parallel to the current detector, wherein the line comprises one or more light-emitting diodes and a switch connected in series for turning ON/OFF the current flowing in the light emitting diodes, the ON/OFF controller controls the ON/OFF period of the switch of each of the lines according to the measured value of current flowing in each of the lines, and the bypass switch is turned ON to bypass the current detector during a light emission period of the light emitting diodes and the bypass switch is turned OFF during a current measurement period by the current detector.