To an organic EL element of a pixel circuit provided in association with an intersection of a scanning line and a data line, a driving current in accordance with digital data or an analog data current is supplied via the data line. When halftones are controlled by digital gray scale in order to reduce power consumption, digital data having a value corresponding to either a first level or a second level is supplied to the pixel circuit. When halftones are controlled by analog gray scale in order to improve display quality, an analog data current is supplied to the pixel circuit.