1. Field of the Invention
The present invention relates to a flat panel display device, and more particularly to a liquid crystal display device with a reduced size and number of parts.
2. Description of Related Art
Various flat panel display devices such as an LCD (Liquid Crystal Display) device, a PDP (Plasma Display Panel), and an ELD (Electro Luminescent Display) are used as display devices in different types of equipment. The LCD device is most widely used as a portable image display device due to its excellent image quality, its light weight, its slimness, and its low power consumption. The LCD device is used as a television monitor, a monitor of a notebook computer, etc.
The LCD device displays an image using the optical anisotropy and the polarity of a liquid crystal. That is, the liquid crystal molecules included in the liquid crystal can be arranged in a predetermined (constant) direction. Further, the direction of the liquid crystal molecule arrangement can be controlled by applying an electric field to the liquid crystal. Therefore, when the molecule arrangement direction of the liquid crystal is arbitrary, the molecule arrangement of the liquid crystal can be changed by applying an electric field. In addition, image information can be displayed by changing the polarization of light in the molecule arrangement direction of the liquid crystal using the optical anisotropy.
Also, the LCD device includes a liquid crystal panel displaying an image and a drive section for driving the liquid crystal panel. The drive section includes a gate driver driving a plurality of gate lines on the liquid crystal panel and a data driver driving a plurality of data lines on the liquid crystal panel. Further, the drive section also includes a timing controller controlling the gate and data drivers and a voltage generating section generating drive voltages required for the liquid crystal panel, the gate driver, the data driver, and the timing controller.
In addition, the voltage generating section generates a gate low voltage VGL and a gate high voltage VGH for driving the gate lines and supplies the gate low and high voltages to the gate driver. The voltage generating section also supplies at least two drive voltages (e.g., Vdd and Vcc) used for driving the circuit devices to the gate driver, the data driver, and the timing controller. In addition, the voltage generating section supplies a common voltage Vcom used as a reference voltage to the liquid crystal panel. Also, the voltage generating section is mounted on a printed circuit board together with the timing controller.
In addition, the printed circuit board including the mounted timing controller is individually provided with a gate low voltage generating circuit for generating the gate low voltage VGL, a gate high voltage generating circuit for generating the gate high voltage VGH, a drive voltage generating circuit for generating the at least two drive voltages, and a common voltage generating circuit for generating the common voltage. Further, wires for transferring voltages from the voltage generating circuits to the liquid crystal panel, the gate driver, the data driver, and the timing controller are formed on the printed circuit board.
Thus, because the voltage generating circuits for generating voltages required for the liquid crystal panel, the gate driver, the data driver, and the timing controller are individually formed on the printed circuit board, a large number of devices are mounted on the printed circuit board. Accordingly, the size of the printed circuit board is larger. Therefore, the size and thickness of the related art LCD device is also increased and the manufacturing time and cost is increased.