Abstract: Provided is a backlight driving apparatus for a non-emissive display device which comprises an inverter (or lamp driver) (110) that converts a DC voltage to a preset voltage, a lamp (120) that emits light in response to the input of the converted voltage from the inverter (or lamp driver) (110), a detector (130) that detects electric current or brightness at the lamp, a controller (140) that controls the pulse width of a digital dimming signal in order to provide an adequate control of the electric current or brightness according to a lamp brightness command, a signal generator (150) that generates a signal with fixed frequency and fixed duty ratio for optimizing the operation of the inverter (or lamp driver) (110) and a digital dimmer (160) that generates an inverter driving signal from the logical intersection of the digital dimming signal generated by the controller (140) and the signal generated by the signal generator (150).