| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a communication terminal which can prolong the service life of a battery installed as a power source, and to provide a data communication system. <P>SOLUTION: At normal times when smart communication is not communicated, the communication terminal switches off the first switch 25 and cuts off a communication control circuit 12 from a battery 19 and places the communication control circuit 12 to go into a power-off state. When an electronic key 2 receives power waves Svc transmitted from the transmitter 8 (9) of a vehicle 1, these power waves Svc are charged via a charge circuit 21. Then, when the charge value of the charge circuit 21 exceeds threshold, a first switch 25 is switched on, and the communication circuit 12 becomes electrically connected to the battery 19, and switches into a power-on state. Consequently, the electronic key 2 is started, and smart communication with the vehicle 1 becomes executable. <P>COPYRIGHT: (C)2010,JPO&INPIT |
