Patent ID: 6963179

Claim:
A frequency synchronization device for a LCD having a plurality of lamps as a background light source, comprising: a power amplification unit arranged in loop, said power amplification unit being electrically coupled to one of said lamps, adapted to generate a synchronous signal, and adapted to send said synchronous signal to said coupled lamp for causing the lamps to operate at a same frequency; a plurality of sampling units, each sampling unit coupled to one of the lamps for sampling current thereof; and a control driving unit being electrically coupled to said sampling units so as to stabilize the current of the lamps; wherein said power amplification unit comprises power amplification elements, store elements, resistors, an inductor, a transformer, a lamp and conducting wires so that a secondary winding of said transformer is adapted to provide said synchronous signal to power amplification elements of a second power amplification unit for conducting in cooperation with said store elements, said resistor, and said conducting wires, said conducted power amplification elements are adapted to control said coupled lamp, and said secondary winding of said transformer has a plurality of coils for controlling said coupled lamp.