| 摘要 |
A backlight unit for an LCD(Liquid Crystal Display) is provided to adopt a low-priced HCFL(Hot Cathode Fluorescent Lamp) as a light source of the backlight unit and control lighting of the HCFL by varying a driving frequency of a resonant tank and an inverter as continuously applying power to both ends of the HCFL, thereby preventing deterioration of life caused by frequent power shut-down as a weak point of the HCFL. A burst MCU(Micro Control Unit)(14) receives a synchronizing signal from a video board(10) or a power board of an LCD(Liquid Crystal Display), and outputs a driving pulse which is synchronized with the synchronizing signal and sequentially generated according to each channel. A scanning MCU(16) is installed according to each channel, and outputs an inverter driving frequency having a light frequency interval and a non-light frequency interval in correspondence with the driving pulse by channel outputted from the burst MCU. An inverter driver(18) generates the switching frequency as the frequency outputted from the scanning MCU, and converts the switching frequency into a square wave to be outputted. An LC(Liquid Crystal) resonant tank(20) causes resonances of the square wave outputted from the inverter driver, and converts the square wave into a sine wave to be outputted. An HCFL(Hot Cathode Fluorescent Lamp)(22) is lightened and driven by the output of the LC resonant tank. |
