CONSTANT VOLTAGE CIRCUIT AND ANALOG ELECTRONIC CLOCK

摘要

There are provided a constant voltage circuit that features low current consumption and stable operation, and an analog electronic clock provided with the constant voltage circuit. The constant voltage circuit includes a differential amplifier circuit which is turned on/off by a predetermined signal and which controls the voltage of a gate of an output transistor on the basis of a reference voltage and a feedback voltage that are received, a switch circuit which is connected to an output terminal of the differential amplifier circuit and which is turned on/off by a predetermined signal, and a voltage holding circuit which is connected between the gate of the output transistor and a power supply terminal and which has a resistor and a capacitor connected in series. An analog electronic clock provided with the foregoing constant voltage circuit that supplies a voltage to at least an oscillation circuit and a frequency division circuit.

主权项

1. A constant voltage circuit comprising:
an output transistor connected between an output terminal and a power supply terminal; a voltage dividing circuit, which is connected between the output terminal and a grounding terminal and which divides an output voltage of the output terminal and outputs a feedback voltage; a reference voltage circuit which outputs a reference voltage; a differential amplifier circuit, which is turned on/off by a predetermined signal and which controls the voltage of a gate of the output transistor on the basis of the reference voltage and the feedback voltage that are received; a switch circuit, which is connected to an output terminal of the differential amplifier circuit and which is turned on/off by the predetermined signal; and a voltage holding circuit, which is connected between the gate of the output transistor and the power supply terminal and which has a resistor and a capacitor connected in series.