A backlight unit includes: a power converter to generate a light-source power voltage according to a voltage control signal; an LED string connected to the light-source power voltage; a short-circuit detector to receive the light-source power voltage and to enable a short-circuit signal; and a light source controller to generate the voltage control signal to interrupt generation of the light-source power voltage when the short-circuit signal is enabled. The short-circuit detector includes: a voltage divider to divide the light-source power voltage to output a detection voltage; and a comparing circuit to generate a reference voltage corresponding to a voltage level of the detection voltage, to compare the reference voltage with the detection voltage, and to enable the short-circuit signal in accordance with a result of the comparison.