摘要 |
<p>A voltage detection circuit 2 detects a voltage of a battery 1 and, when the voltage thus detected is within a tolerable input voltage of a power source unit 5, an on/off signal transmitter circuit 4 allows an on/off signal generator circuit 3 to transmit an on/off signal S2 to the power source unit 5. When the voltage of the battery 1 becomes lower than a lower limit of the tolerable input voltage range of the power source unit 5 due to increase of a power consumption of a load 6 thereof, the on/off signal transmitter circuit 4 transmits an off signal S3 to the power source unit 5 regardless of the on/off signal S2 from the on/off signal generator circuit 3. Thus, it is possible to prevent an erroneous operation of the load due to abnormal operation of the power source unit. <IMAGE></p> |