An object is to enable application of forward/reverse voltage to or forward/reverse current to a display element and to lower power consumption of a driver circuit for driving a pixel. A memory storing the potential of a source signal line input through a switch, a first transistor whose gate is supplied with one output of the memory, a second transistor whose gate is supplied with the other output of the memory, a display element electrically connected to one of a source a drain of a first transistor and one of a source and a drain of a second transistor, a power source line electrically connected to the other of the source and the drain of the first transistor and the other of the source and the drain of the second transistor, and a counter power source electrically connected to the display element are included.