Patent ID: 7285922

Claim:
A driving apparatus for a cold cathode fluorescent lamp (CCFL), comprising: an oscillator for oscillating at a frequency based on a tuning resistor and a tuning capacitor, the oscillating frequency increasing in proportion to current flowing in the tuning capacitor; a pulse width modulation (PWM) driver for outputting a PWM switching control signal having an adjusted on/off duty rate and a predetermined cycle based on a reference clock outputted from the oscillator; an inverter for inverting direct current into alternating current of a predetermined frequency, the inverter including a plurality of switching devices of a half bridge structure which switch on and off alternately in response to the switching control signal outputted from the PWM driver; a resonance circuit for outputting the alternating current outputted from the inverter as a lamp driving voltage; a feedback circuit for detecting openness of the lamp through the feedback of a voltage applied to the lamp, and according to the openness detection, outputting a current control signal; and a current controller for increasing a tuning capacitor current of the oscillator if the lamp is open and for decreasing the tuning capacitor current of the oscillator to a reference level if the lamp is not open, in response to the current control signal applied from the feedback circuit.