| 摘要 |
PURPOSE:To obtain a voltage detecting circuit which is easily adjusted by generating plural reference voltages different in level from the stabilization output of a voltage to be detected through resistance division. CONSTITUTION:The series circuit of resistances R11, R2, and R3 is interposed between the output terminal of a regulator 12 and a reference potential point. When a battery voltage V3 is sufficiently high, output voltages V01 and V02 of comparators 13 and 14 are 0V. When the voltage V3 drops and its divided voltage VB1 drops below a reference voltage, the output voltage of the comparator 13 rises from 0 to a voltage VR and a control circuit 15 judges that the voltage V3 attains to an alarm level and drives an alarm display circuit. Then, when the voltage V3 further drops and the divided voltage VB1 drops further below the reference voltage. The output V02 of the comparator 14 also varies from 0 to a voltage VR. The circuit 15 judges that the voltage V3 reaches a shut-out level and stops the operation of equipment. Thus, an alarm and a shut- off detection level are set with one variable resistor R5, so the detection levels are easily adjusted and the manufacture cost of the circuit is reduced.
|
