DEVICE FOR DRIVING BACK LIGHT

摘要

PURPOSE: A device for driving a back light is provided to grasp a state of a lamp by detecting the size of a current that flows through a lamp without installing the leading wire for feeding back the current directly to an inverter PCB(Printed Circuit Board). CONSTITUTION: A lamp unit(600) includes a lamp(601) and an electric condenser(C1). A transformer(T1) is connected to the lamp unit for supplying a current which turns on the lamp. An oscillator(200) is connected with primary coils(L11,L12) of the transformer for supplying an alternating current. A current detector(300) detects a current flowing through the oscillator or the primary coils of the transformer. A switching unit(Tr1) switches an external current for supplying the same to the transformer and the oscillator. A pulse width modulator(400) controls the switching unit according to the signal and a dimming control signal.