A voltage corresponding to the maximum voltage value among respective terminal voltages at least at the time of light emission of organic EL elements is held in a hold circuit, and a power source circuit which generates electric power having a voltage higher by a predetermined value than the voltage held as a power source voltage is provided. The power source voltage is caused to follow and vary depending on the maximum voltage value among the respective terminal voltages at the time of light emission, and is determined as a power source voltage for the output stage current sources. Further, in order to permit operation of the respective output stage current sources with a difference voltage between the power source voltage and the maximum voltage value, the predetermined value is set at the difference voltage or a voltage higher than the difference voltage.