Patent ID: 8525433
Filing Date: 2013-09-03
Classification: H05B,Y02B

Abstract:
1. A light emitting diode (LED) light emitting device comprising: a plurality of LED channels that are arranged in parallel and formed with a plurality of LED elements that are continuously connected in series; and a constant current source that controls each channel current flowing to the plurality of LED channels according to a predetermined channel reference current to be a predetermined setting channel current, wherein the constant current source comprises a plurality of operating amplifiers that control the magnitude of each of the channel currents and sets an offset voltage of each of the plurality of operating amplifiers so that an actual channel current is identical to the predetermined setting channel current, wherein a feedback voltage generating according to a predetermined offset reference current for an offset setting period that sets the offset voltage of the plurality of operating amplifiers is input to a first input terminal of the operating amplifier, a reference voltage generating according to the channel reference current is input to a second input terminal of the operating amplifier, and a difference between a voltage of the second input terminal and a voltage of the first input terminal is identical to the offset voltage.