JPS6298436U

JPS6298436U -

Info

Publication number: JPS6298436U
Application number: JP19078485U
Authority: JP
Priority date: 1985-12-10
Filing date: 1985-12-10
Publication date: 1987-06-23

Description

[Brief explanation of the drawing]

第１図ａ，ｂは、本考案の一実施例を示し、第
１図ａは本考案の充電回路を示す回路図、第１図
ｂは制御装置の構成を示す簡略ブロツク図、第２
図ａ，ｂ，ｃは、本考案の充電回路の動作状態を
説明するための図であり、第２図ａは二次電池と
してのコンデンサの電圧を示すタイムチヤート、
第２図ｂはスイツチング回路の動作状態を示すタ
イムチヤート、第２図ｃはマイクロコンピユータ
からの制御信号のタイムチヤート、第３図ａ，ｂ
は、従来の回路構成の一例を示す回路図及びブロ
ツク図、第４図及び第５図は、同上、従来の充電
回路の動作状態を説明するためのタイムチヤート
である。Ｂ……充電回路、Ｃｂ……コンデンサ、Ｒｂ，
Ｒ_５，Ｒ_６，Ｒ_７……抵抗、Ｄｂ……ダイオード
、ＺＤｂ……ツエナーダイオード、Ｑｂ，Ｑｂ′
……トランジスタ。 1A and 1B show an embodiment of the present invention, FIG. 1A is a circuit diagram showing a charging circuit of the present invention, FIG. 1B is a simplified block diagram showing the configuration of a control device, and FIG.
Figures a, b, and c are diagrams for explaining the operating states of the charging circuit of the present invention, and Figure 2 a is a time chart showing the voltage of a capacitor as a secondary battery.
Figure 2b is a time chart showing the operating status of the switching circuit, Figure 2c is a time chart of control signals from the microcomputer, and Figures 3a and b.
1 is a circuit diagram and a block diagram showing an example of a conventional circuit configuration, and FIGS. 4 and 5 are time charts for explaining the operating state of the conventional charging circuit. B...Charging circuit, Cb...Capacitor, Rb,
R ₅ , R ₆ , R ₇ ... Resistor, Db ... Diode, ZDb ... Zener diode, Qb, Qb'
...Transistor.

Claims

[Scope of utility model registration request]

A secondary power source that serves as a backup power source for retaining the contents of volatile memory in an electronic control device that has a built-in microcomputer and volatile memory and performs control operations while referring to the contents of the volatile memory according to a stored operation program. In the charging circuit for a secondary battery, there is a constant voltage power supply circuit that charges the volatile memory by keeping the charging voltage below the content retention voltage until a certain period of time has elapsed, and a constant voltage power supply circuit that charges
A switching circuit is provided to control the start of charging of the capacitor for discharging, and the capacitor is charged in advance to less than the content holding voltage of the volatile memory until a certain time has elapsed, and the start of charging of the capacitor is controlled by a control signal from the microcomputer. A charging circuit characterized by: