Patent attributes
A demodulation signal is generated by provision of a demodulation signal generation circuit to the semiconductor device capable of wireless communication and by obtainment of a difference between voltages having opposite polarities by the demodulation signal generation circuit. Alternatively, a plurality of demodulation signal generation circuits and a selective circuit which selects a demodulation signal generation circuit depending on characteristics of a received signal are provided, where operation of a second demodulation signal generation circuit stops when a first demodulation signal generation circuit is operated. The selective circuit includes an inverter circuit, a flip-flop circuit, and a selector circuit. When the second demodulation signal generation circuit has a comparator and the like, power consumption thereof is reduced.