An input side drive current of a D/A converter circuit is controlled by a switch circuit connected in series with at least one of a plurality of input side transistors connected in parallel to form a current mirror connection. By turning the switch circuit from ON to OFF, a constant current flowing through the input side transistor, which is turned OFF by the switch circuit, is distributed to the remaining input side transistors, resulting in a large D/A converted current in a current mirror connected output side transistor. Thus, it is possible to correspondingly reduce a value of a display data, so that the number of bit positions of the D/A converter circuit can be reduced by 1 or more.