Patent ID: 8492992

Claim:
An LED lighting device comprising: a rectifying circuit having AC input ends connectable to an AC source; a step-down converter configured to light the LED lighting device, the converter comprising: input ends connectable to DC output ends of the rectifying circuit, and output ends, to which an output capacitor of the step-down converter is connected in parallel, connected to an LED; a control unit configured to change continued DC output current of the converter in accordance with a dimming degree of a dimmer to which AC voltage is applied; and a bypass circuit connected to the output ends of the converter in parallel with the output capacitor and configured to reduce fluctuation in the DC output current to the LED lighting device by making bypass current flow, the bypass current being larger than a lighting current at least in the vicinity of a dimming lower limit of the LED, wherein the lighting current flows through the LED and wherein the bypass circuit is configured such that bypass current bypasses the LED, wherein the bypass circuit is controlled so as to make bypass current flow only in a predetermined range of the vicinity of the dimming lower limit of the LED.