A semiconductor display device which can suppress the drive frequency while increasing the number of gray scales. According to the semiconductor display device, a plurality of pixels can be selected per row by a first scan line driver circuit, the plurality of pixels can be selected per row by a second scan line driver circuit, writing of a first video signal to the row selected by the first scan line driver circuit is controlled by a signal line driver circuit, writing of a second video signal to the row selected by the second scan line driver circuit is controlled by the signal line driver circuit, and using respective selection circuits included in the first and second scan line driver circuits, the output from the second scan line driver circuit to the plurality of pixels can be set at high impedance while the row is selected by the first scan line driver circuit, or the output from the first scan line driver circuit to the plurality of pixels can be set at high impedance while the row is selected by the second scan line driver circuit.
