Patent ID: 8400073

Claim:
A backlight unit comprising: a boosting circuit that boosts an input voltage to a light source driving voltage; a light source unit that includes a plurality of light source strings grouped into a plurality of light generating groups, the light source strings being commonly connected to an output terminal of the boosting circuit to generate a light in response to the light source driving voltage; a plurality of driving circuits each connected to the light generating groups, respectively, and configured to sequentially output feedback voltages fedback from the light source strings of a corresponding light generating group of the light source generating groups; a minimum voltage detecting circuit that receives the feedback voltages from the driving circuits, compares the feedback voltages with each other to detect a minimum voltage, and outputs a control signal according to the detected minimum voltage; and a voltage control circuit that controls the boosting circuit in response to the control signal to control a voltage level of the light source driving voltage supplied to the light source unit, wherein each of the driving circuits comprises: a plurality of switching devices each of which is connected to the light source strings of the corresponding light generating group to receive the feedback voltages, and a plurality of D-flip-flops connected to the switching devices, respectively, to sequentially supply an output signal to the switching devices in response to the clock signal.