A black-level reference-voltage generation circuit is disposed in a vicinity of an input-and-output pad section, and a power-supply line for the black-level reference-voltage generation circuit is connected to a power-supply line for a reference-voltage generation circuit for the other gradation levels at a position in a vicinity of the input-and-output pad section. With this, the resistance of the wiring resistor of the power-supply line of the black-level reference-voltage generation circuit is made as low as it can be ignored. As a result, a voltage drop caused by the wiring resistor of a black-level reference voltage is eliminated.