JPS63103109U

JPS63103109U -

Info

Publication number: JPS63103109U
Application number: JP19769686U
Authority: JP
Priority date: 1986-12-23
Filing date: 1986-12-23
Publication date: 1988-07-04

Description

[Brief explanation of the drawing]

第１図は、本考案の一実施例の回路図、第２図
は従来例における定電圧回路の回路図、第３図は
従来例における電源電圧検出回路の回路図である
。１，１０，２０……基準電圧発生部、２，１２
……出力電圧検出部、３，２３……電源電圧検出
部、４，１４，２４……比較回路、５……検出電
圧切換部、５ａ，５ｂ，６ａ，６ｂ，１８……ス
イツチングトランジスタ、６……出力振分部。 FIG. 1 is a circuit diagram of an embodiment of the present invention, FIG. 2 is a circuit diagram of a conventional constant voltage circuit, and FIG. 3 is a circuit diagram of a conventional power supply voltage detection circuit. 1, 10, 20...Reference voltage generation section, 2, 12
... Output voltage detection section, 3, 23 ... Power supply voltage detection section, 4, 14, 24 ... Comparison circuit, 5 ... Detection voltage switching section, 5a, 5b, 6a, 6b, 18 ... Switching transistor, 6...Output distribution section.

Claims

[Claims for Utility Model Registration] A constant voltage circuit that inputs a voltage proportional to the output voltage and a reference voltage from a reference voltage generation circuit to a comparison circuit, and controls the output voltage based on the output of the comparison circuit; A power supply voltage detection circuit that inputs a voltage proportional to the power supply voltage and a reference voltage from the reference voltage generation circuit to a comparison circuit, and uses the output of the comparison circuit as a detection signal of the power supply voltage, the constant voltage circuit described above. A power supply circuit for a small electronic device, characterized in that a comparison circuit and a reference voltage generation circuit in the power supply voltage detection circuit and the above-mentioned power supply voltage detection circuit are used as a common comparison circuit and a reference voltage generation circuit, and the comparison circuit and the reference voltage generation circuit are switched and used.