Semiconductor device

A semiconductor device comprising:

• an antenna circuit which transmits and receives data;
• a first demodulation signal generation circuit configured to demodulate a signal from the antenna circuit, whose modulation factor is greater than or equal to 95% and less than or equal to 100%;
• a second demodulation signal generation circuit configured to demodulate a signal from the antenna circuit, whose modulation factor is greater than or equal to 95% and less than or equal to 100% and a signal from the antenna circuit, whose modulation factor is greater than or equal to 10% and less than or equal to 30%;
• and
• a logic circuit configured to select one of a signal demodulated in the first demodulation signal generation circuit and a signal demodulated in the second demodulation signal generation circuit to modulate a signal from the antenna circuit,
• wherein the second demodulation signal generation circuit includes:
• a first demodulation circuit;
• a second demodulation circuit;
• and
• a comparator electrically connected to the first demodulation circuit and the second demodulation circuit,
• wherein a polarity of electric signal demodulated in the first demodulation circuit is opposite to that of electric signal demodulated in the second demodulation circuit,
• wherein the logic circuit is configured to select the signal demodulated in the first demodulation signal generation circuit when the antenna circuit transmits data, and
• wherein the logic circuit is configured to select the signal demodulated in the second demodulation signal generation circuit when the antenna circuit receives data.