A semiconductor device includes a display device and a source driver. Each of a plurality of pixels included in the display device is supplied with a first data potential and a second data potential included in a range of a first potential or higher to a second potential or lower. The first data potential makes the pixel display an image with a first gray level. The pixel performs calculation with the first data potential and the second data potential to generate a third data potential. The third data potential makes the pixel display an image with a second gray level. A reference potential of the first data potential is an intermediate potential between the first potential and the second potential, and the gray level width that can be displayed by the second data potential is larger than the gray level width that can be displayed by the first data potential.