There are provided a data register (8) for driving an EL element (6) by a current flowing in a data line (3) via a TFT (5) while sequentially capturing input digital video data for each data line, a latch circuit (10) for holding the data received in the data register (8) during 1 H period, and n analog switches (120 to 123) provided between each data line (3) and a power supply line (11), to which n bit of digital video data for each one data line is input bit by bit as each control signal. The transistors constituting each switch are made different sizes. As the current amount flowing in each switch therefore differs, the EL element emits light with a luminance in accordance with the digital video data.