To apply the LCD display device to both a multiplex and a static driving systems by providing a static driving type LCD display unit which inputs one segment output from an LCD driver circuit at its common electrode terminal and inputs respective segment outputs from segments other than the said segment at respective segment electrode terminals.

To the common electrode terminal of the static driving type LCD display unit 4, one (e.g. Sn) of segment outputs of a 1/2-duty driving type LCD driver IC3 is connected. To the respective segment electrode terminals S1-S4 of the static driving type LCD display unit 4, some (e.g. S1, S2, S3, and S4) of the segment outputs S1 to Sn-1 other than the segment output Sn connected to the common electrode terminal of the static driving type LCD display unit 4 are inputted.