| 摘要 |
PURPOSE:To eliminate the need to replace a battery for a long period by deciding the operation state of a device, deciding the battery voltage before operation wherein a large current flows to a load, and placing a power source boosting circuit in operation when the battery voltage is low. CONSTITUTION:In normal operation, a current flows from the battery 1 only to a control part 10. For example, when the control part 10 tries to drive a load coil 12 with pulses, a source voltage guaranteeing means 22 places a battery voltage deciding circuit 7 in operation to confirm whether or not the remaining capacity of the battery 1 is sufficient, and when the remaining capacity is sufficient, a load driving terminal 31 is turned ON and OFF to turn ON and OFF a transistor(TR) 17, thereby driving the load coil 12 with pulses. When the capacity of the battery 1 is less than the lowest necessary remaining capacity, a load driving terminal 30 is turned ON and OFF to turn ON and OFF a TR 13, thereby driving the load coil 12 with pulses. At this time, a large intermittent current flows to the coil 34 of a voltage boosting circuit 9 and a high voltage generated when the current turns OFF is charged in a capacitor 8 to secure a voltage supplied to the control part 10. |
