IC TAG HAVING FUNCTION CHANGING MEANS

PROBLEM TO BE SOLVED: To enhance security while preserving a simple structure of an IC tag. SOLUTION: The IC tag is composed of separable parts A1 and A2, and a nonseparable part B. An IC1 and an IC3 are connected through a signal line L1 for transmitting signal, and an IC2 and an IC3 are connected through a signal line L2 for transmitting signal. The signal line L1 is wired such that it will be disconnected when the part A1 is separated from the tag main body, and the signal line L2 is wired such that it will be disconnected in the same manner when the part A2 is separated from the tag main body. SL13, SL31 are wired such that they will be disconnected when the A1 part is separated, and the line SL23, SL32 are wired such that they will be disconnected when the A2 part is separated. The lines SL13, SL31, SL23, and SL32 are provided to detect a change in impedance of lines resulting from the line disconnection and to be used for checking if the A1 part or the A2 part is separated or not. COPYRIGHT: (C)2006,JPO&NCIPI