VOLTAGE GENERATING DEVICE FOR ASSIGNING INTENSITY LEVEL AND INTENSITY LEVEL DISPLAY DEVICE PROVIDED WITH THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a voltage generating device for assigning intensity, which carries out charging of electricity to an intensity level display element while switching rapid charging through a low power impedance circuit, such as a buffer circuit and low power consumption charging without passing through the circuit, and to provide a device for displaying gradation, having the same.;SOLUTION: In a source driver 92, having a reference voltage generator circuit 38 for generating tone display voltage and a D/A converter circuit 36 for selecting and outputting the tone display voltage to a liquid crystal panel, a buffer circuit part 41, having a buffer circuit and an analog switch circuit is provided between the reference voltage generator circuit 38 and the D/A converter circuit 36. The analog switch circuit switches modes of connection among the reference voltage generator circuit 38, the buffer circuit and the D/A converter circuit 36, so as to select whether to output the tone display voltage to the D/A converter circuit 36 via the buffer circuit or without utilizing the buffer circuit. The operation of the analog switch circuit is controlled by an analog switch control circuit part 40.;COPYRIGHT: (C)2002,JPO