Power supply device for driving light emitting diode

A power supply device for driving a light emitting diode (LED), the device comprising:

• a power conversion unit converting an input power into a plurality of first powers according to a pre-set first conversion scheme and converting the input power into a second power according to a second conversion scheme set to be different from the first conversion scheme;
• a current balancing unit maintaining current balancing of the plurality of first powers from the power conversion unit;
• an LED driving unit supplying the plurality of first powers maintained in current balancing by the current balancing unit to a plurality of LED units, respectively, and detecting a power and a current supplied to the LED units;
• an operating unit performing a pre-set operation upon receiving the second power from the power conversion unit;
• a feedback unit having a first feedback unit feeding back a detection signal from the LED driving unit and a second feedback unit feeding back a detection signal detecting the voltage of the second power supplied to the operating unit;
• and
• a power conversion controller controlling a power conversion switching frequency of the plurality of first powers of the power conversion unit according to the detection signal from the feedback unit and controlling the duty of the second power of the power conversion unit, in synchronization with the power conversion switching frequency.