power SUPPLY APPARATUS FOR LIQUID CRYSTAL DISPLAY

摘要

PURPOSE: A power supply apparatus is to supply analog power source of constant level to a thin film transistor. CONSTITUTION: A first voltage conversion part(10) and a second voltage conversion part(30) output the input voltage after converting to a set voltage, and a comparison part(50) outputs a corresponding comparison voltage after comparing output voltages from the first and the second voltage conversion part, and the comparison voltage is fed back to the second voltage comparison part. The second voltage comparison part corrects the output voltage according to the comparison voltage which is fed back, and the sum voltage of corrected output voltages of the first and the second voltage conversion part is supplied to a gradation part generating a gradation voltage of the liquid crystal device and to a source IC supplying a pixel voltage to a liquid crystal pixel.