| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a carrier extraction circuit, a RF tag, and a contactless IC card capable of avoiding a malfunction of an internal circuit even when a change in the amplitude of an AC signal induced in an antenna is great. <P>SOLUTION: The carrier extraction circuit connectable to the antenna receiving an electromagnetic wave, in one terminal a of which a first AC signal INa is induced and in the other terminal b of which a second AC signal INb inverse to the first AC signal INa is induced, includes a binary circuit 31a for binarizing the first and second AC signals INa, INb to output first and second binary pulses BINP, BINM; a pulse generating circuit 32 for generating a first trigger pulse TRGP synchronously with the first binary pulse BINP and generating a second trigger pulse TRGM synchronously with the second binary pulse BINM; and an output circuit 33a for receiving the first and second trigger pulses TRGP, TRGM and outputting a clock CLK with a fixed duty ratio. <P>COPYRIGHT: (C)2007,JPO&INPIT |
