Gradation voltage selection circuit, the driver circuit, liquid crystal drive circuit, a liquid crystal display device

摘要

PROBLEM TO BE SOLVED: To provide a gradation voltage selecting circuit whose circuit scale can be made small.;SOLUTION: In the gradation voltage selecting circuit, 1st gradation selecting MOS transistor groups (SS0), M-pieces half gradation voltage MOS transistor groups (SSa, SSb), and 2nd gradation selecting MOS transistor groups (SS1) equally divides a gradation voltage between a 1st gradation voltage and a 2nd gradation voltage to generate (M+1) half gradation voltages. At this time, high resistance of several megaohoms or more by ON resistance of the 1st gradation selecting MOS transistor groups (SS0), M-pieces half gradation voltage MOS transistor groups (SSa, SSb), and 2nd gradation selecting MOS transistor groups (SS1). This gradation voltage selecting circuit needs not use a resistance element having a resistance value of several ohoms or more in the circuit, so the circuit scale of the gradation voltage selecting circuit, the circuit scale of a source driver circuit, and the circuit scale of a liquid crystal drive circuit can be made smaller than before.;COPYRIGHT: (C)2006,JPO&NCIPI