Patent ID: 6369790
Filing Date: 2002-04-09
Classification: G09G

Abstract:
A liquid crystal driving circuit comprising:a function generating part for generating k (&gE;2) kinds of function values for k fields on the basis of a field start signal, a shift clock and an alternating signal; a common electrode driving circuit for simultaneously selecting k common electrodes on the basis of said field start signal and said shift clock and for applying a plurality of kinds of common voltages to the selected k common electrodes; a RAM for display data, in which data to be displayed on a liquid display part are stored; and a segment electrode driving circuit including: data storing means for storing therein k+1 values in accordance with said k function values and 2k k-bit data and for simultaneously outputting 2k values on the basis of said alternating signal and a field select signal; 2k power supply lines provided so as to correspond to 2k outputs of said data storing means; a first analog multiplexer for connecting each of said 2k power supply lines to one of k+1 power supplies, each of which has a potential different from each other, on the basis of a corresponding one of said 2k outputs of said data storing means corresponding to a corresponding one of said 2k power supply lines; and a second analog multiplexer, provided for each of segment electrodes, for receiving k display data corresponding to said selected k common electrodes from said RAM for display data, and for selecting one of said 2k power supply lines on the basis of said k display data to connect the selected one of said 2k power supply lines to a corresponding one of said segment electrodes.