| 摘要 |
<p>PURPOSE:To improve the power source use efficiency of a card power source by executing control so that the information reading operation of an information memory can not be executed when it is not necessary to read information data which are housed to the information memory of an information card. CONSTITUTION:An information card 4 has an antenna 11 which is composed of 1/2 wavelength dipole antenna. When the information card 4 is irradiated with an information retrieving signal W1, this irradiation is automatically detected by an operation command detecting circuit 16 and a clock oscillating circuit 18 is in an oscillation operating condition. In a condition that the card is not be irradiated with the information retrieving signal W1, the clock oscillating circuit 18 is left in a nonoperating condition. Accordingly, only when it is necessary to read the information data by an information reading device 2, a power source VB to be needed for the oscillating operation of the clock oscillating circuit 18 and the information reading operation of an information memory 13 is supplied from an information card power source 19 to the informa tion card 4. Then, in the other condition, the power source output of the informa tion card power source 19 can be prevented from being consumed. Thus, the use efficiency of the power source can be improved.</p> |
