Low Power-Consumption Card Reader for Use with a Contactless IC Card

摘要

PURPOSE: A low-power consuming card reader used for a non-contact typed IC card is provided to operate in an active state for reading data from the IC card if the IC card is detected on a waiting state, which is periodically generating a signal for detecting the IC card in normal times. CONSTITUTION: A wake-up pulse signal generator(202) generates a clock signal periodically in a sleep state. A controller(204) judges approach of the IC card by generating an approach detecting signal as receiving the clock signal, and switches the state of the card reader to the waiting or the active state. A resonance circuit(210) generates the induced current when the IC card is detected within an approach detecting distance by transmitting the approach detecting signal through an antenna(211). A counter(214) counts the clock number of the approach detecting signal. A demodulator(216) demodulates the received data from the IC card. A modulator(208) generates the transmission data by modulating an amplitude of the control data. A clock signal generator(206) generates the standard clock signal needed to transmit/receive the transmitting/receiving data.