A decoder with reduced power consumption is provided. The decoder includes a first circuit and a second circuit for holding data. The second circuit includes a first transistor, a second transistor, and a third transistor. The first transistor and the second transistor include an oxide semiconductor in a channel formation region. The third transistor includes silicon in a channel formation region. A gate of the second transistor is electrically connected to one of a source and a drain of the first transistor and a gate of the third transistor is electrically connected to one of a source and a drain of the second transistor. The decoder is configured to provide or stop power supply to the semiconductor device depending on a packet ID of a header portion of the data and to perform data storing or restoring of data between the first circuit and the second circuit.