Driving Circuit Design Of TFT Liquid Crystal Module

As the representative of the flat panel display, LCD (Liquid Crystal Display) has been rapidly developed and widely used in the field of display. In order to drive the LCD with high resolution and improve the displaying quality, people designed a TFT (Thin-Film Transistor) on every pixel of LCD to control display pixels independently. TFT is a nonlinear active device. The display with TFT is called TFT-LCD.In this paper, we design and make a drive system for TFT-LCD on the base of Liquid Crystal Module and inverter provided by Suzhou AUO (AU Optronics Corp). Therefore, the driving theory of TFT-LCD is described and discussed in detail Firstly. According to the TFT-LCD with LVDS (Low Voltage Difference Signal) interface supplied by AUO (AU Optronics Corp). We analyzed the characteristic of LVDS interface.Based on the analysis of the driving theory of TFT-LCD and the characteristic of LVDS interface, we designed a drive circuit to control the horizontal/vertical synchronization signals and pixel signal, this drive circuit has a LVDS interface. We make and debug the drive circuit by using performance-to-price FPGA EP1C3T144 and LVDS transmitting chip DS90C387.There is a voltage inverter circuit provided by Suzhou AUO used to supplying working voltage for the CCFL (Cold Cathode Fluorescent Lamp) of LCD back light module. In order to supply adjustable voltage for the voltage inverter circuit, an output adjustable DC voltage stabilizer power supply circuit is designed. In this circuit it conclude SCM (Single Chip micro-controller), D/A (digital/analogue) converter, and a 3-terminal adjustable positive voltage regulator. Also this circuit can display the output voltage values with light-emitting diodes real-timely.After debugging and running .The display driving circuit and the adjustable steady voltage power supply circuit designed in this paper attained a good display effect on the TFT-LCD with LVDS interface.