MULTI-OUTPUT DC/DC VOLTAGE CONVERTING APPARATUS AND LIQUID CRYSTAL DISPLAY, INCLUDING MULTI-OUTPUT DC/DC VOLTAGE CONVERTER FOR GENERATING MAIN POWER THROUGH CHOKE SYSTEM AND AUXILIARY POWER THROUGH FLYBACK SYSTEM

摘要

PURPOSE: A multi-output DC/DC voltage converting apparatus and a liquid crystal display are provided to obtain a multi-output by combining a choke system and a flyback system, and obtain a high efficiency main power source. CONSTITUTION: A liquid crystal display comprises a liquid crystal panel, a gate driving circuit, a source driving circuit, a gradation voltage generator, and a multi-output DC/DC voltage converter(5). The liquid crystal panel has a plurality of pixels arranged into a matrix in a region defined by a plurality of gate lines and a plurality of data lines formed orthogonally to the gate lines. The gate driving circuit sequentially scans pixels on the liquid crystal panel, by one column, by sequentially applying a gate-on voltage to the gate lines. The source driving circuit takes, as an input, a color signal and a plurality of gradation voltages, selects the gradation voltage corresponding to the color signal, and applies the selected gradation voltage to the data lines of the liquid crystal panel. The gradation voltage generator generates a plurality of gradation voltages from a data driving voltage, and supplies the gradation voltages to the source driving circuit. The multi-output DC/DC voltage converter generates a main power(Vd) and two or more auxiliary powers(Von,Voff) from a primary coil(T61) and secondary coils(T62,T63) of a transformer from an input voltage(Vin) by using the transformer, and outputs the main power as a data driving voltage and the auxiliary powers as a gate-on voltage and a gate-off voltage.