ID TAG AND RECEIVING POWER CONTROL METHOD OF ID TAG

摘要

PROBLEM TO BE SOLVED: To provide an ID tag capable of properly obtaining each power source for each operation even when data are collectively read by a reader in a condition that plural articles are piled. SOLUTION: A CPU 16 of the ID tag 11 detects a voltage level of the power source for actions generated and outputted by a smoothing circuit 17 on the basis of a radio wave signal transmitted from the reader by an A/D converter part 20, and controls so that a resonant frequency f a resonant circuit 15 varies by varying a number of connections of capacitors 14 in correspondence with the voltage level.