| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a battery driven device where the possibility that the operation stops without being notified is low, and to provide a sensor system using the battery driven device. <P>SOLUTION: Between the operations of a standby mode 41 where power consumption is reduced, the operation of a read mode 42 for reading the output of a sensor and the operation of a transmission mode 43 which is the maximum consumption mode for transmitting a radio signal are performed intermittently. At a timing Tc of once every time when the operation modes 41-43 are switched, the comparison operation of comparing the battery voltage and a predetermined notification voltage is performed, and notification is performed if the battery voltage is lower than the predetermined notification voltage in the comparison operation. Since the comparison operation is performed once surely in the maximum consumption mode, i.e. the transmission mode 43, the possibility that the operation stops without being notified low when compared with a case where there is a possibility that the comparison operation is not performed in the transmission mode 43. <P>COPYRIGHT: (C)2012,JPO&INPIT |
