Patent ID: 7479954

Claim:
A power supply circuit which generates driving voltages for an electro-optic device having a plurality of common electrodes and a plurality of segment electrodes with the use of multi-line driving in which four lines of common electrodes are simultaneously selected, the driving voltages being first through seventh driving voltages in which an i-th (2≦i≦5, and i is an integer) driving voltage is higher than an (i+1)th driving voltage, the power supply circuit comprising: a common electrode driving-voltage generator circuit which generates the first and seventh driving voltages used for selection of the common electrodes at a positive side and a negative side on the basis of the fourth driving voltage; and a segment electrode driving-voltage generator circuit which generates the fourth driving voltage, the second and third driving voltages used for the segment electrodes at the positive side on the basis of the fourth driving voltage, and the fifth and the sixth driving voltages used for the segment electrodes at the negative side on the basis of the fourth driving voltage, wherein the segment electrode driving-voltage generator circuit changes and outputs output potentials of only the third and fifth driving voltages from among the second through sixth driving voltages, while a voltage difference between the third and fourth driving voltages is kept equal to a voltage difference between the fourth and the fifth driving voltages.