| 摘要 |
PURPOSE:To indicate the life of battery when different in the battery voltage by indication different from the normal indication in two different voltage ranges according to output signals of a detection means adaped to detect at least four ranges of the battery voltage. CONSTITUTION:A first voltage detection circuit 10a outputs an H signal when the battery voltage exceeds 2.4V. A second voltage detection circuit 10b outputs the H signal when it exceeds 1.9V. A third voltage detection circuit 10c outputs the H signal when it exceeds 1.4V. When 3V battery system is used as supply source 9, an OR gate 10f outputs an L signal as the battery voltage is below 2.4V, and a control circuit 4 generates a signal for quick turning of a rotor 7 of a step motor at an interval of 2sec. When 1.5V battery system is used, the OR gate 10f outputs the L signal as the battery voltage is below 1.4V to quickly turn the rotor 7 at the interval of 2sec. |
