To solve a problem that the battery life of a portable terminal such as a portable telephone whose device is driven by a battery is largely affected because the drive voltage of liquid crystal has to be high in order to generally perform color display on the liquid crystal display compared with monochrome display.

A controlling part 1 has a counter part 1a and a switching part 1b and transmits a color information signal to a display part driving circuit 2 so as to display desired hues in the case of performing color display of the liquid crystal. The driving circuit 2 realizes data corresponding to the color information by applying voltage generated by a voltage generating part 3. In the cafe of performing monochrome display, the controlling part 1 transmits only data n0 for making each dot 4 of the liquid crystal display/non-display. Each dot 4 in a monochrome liquid crystal display mode performs display only with voltage v0 generated by the generating part 3 for performing monochrome display.