To provide a display device with high image quality and fewer terminals. The present invention is made with a focus on the positional relation between a serial-parallel conversion circuit and an external connection terminal for supplying a serial signal to the serial-parallel conversion circuit. The structure conceived is such that a serial-parallel conversion circuit and an external connection terminal for supplying a serial signal to the serial-parallel conversion circuit are provided close to each other so that an RC load between the serial-parallel conversion circuit and the external connection terminal is reduced.