| 摘要 |
<P>PROBLEM TO BE SOLVED: To restrict communication distance in an ID tag, while realizing stable communication, without deteriorating the efficiency of communication. <P>SOLUTION: When a semiconductor integrated circuit device 1 is operated, an operation control part 11 sets existence or nonexistence of the communication distance restriction for shortening the communication distance in a state management part 10. When there is no communication distance restriction, an Lo signal is outputted from an AND circuit 15, a switch part 16 is turned ON, and a command, demodulated from a command demodulation circuit 4, is inputted in a command decoding part 9. When the communication distance restriction is set, an electric power intensity monitor part 14 determines if the electric power of a rectification circuit 2 is a set electric field intensity or higher. When it is lower than the set electric field intensity, the output of the AND circuit 15 that has become a Hi signal, the switch part 16 is turned OFF, the various commands demodulated by the command demodulation circuit 4, is not inputted in the command decoding part 9, and consequently the semiconductor integrated circuit device 1 does not operate. <P>COPYRIGHT: (C)2009,JPO&INPIT |
