JPH0299420U

JPH0299420U -

Info

Publication number: JPH0299420U
Application number: JP810189U
Authority: JP
Priority date: 1989-01-26
Filing date: 1989-01-26
Publication date: 1990-08-08
Anticipated expiration: 2004-01-26
Also published as: JP2587705Y2

Description

[Brief explanation of drawings]

第１図は請求項１に記載の本考案の実施例の回
路図、第２図は請求項２に記載の本考案の実施例
の構成を示すブロツク図、第３図および第４図は
従来のＣＰＵリセツト回路の回路図である。符号の説明、１……ＣＰＵ、２……ＣＰＵリセ
ツト回路、３……検知回路、４……負荷制御回路
、Ｑ１……第１のトランジスタ、Ｑ２……第２の
トランジスタ、ＲＳＴ……リセツト端子、ＶＤＤ
……第１の電源ライン、ＶＣＣ……第２の電源ラ
イン、Ｖ１……第１の基準値、Ｖ２……第２の基
準値、ＺＤ１……第１のツエナーダイオード、Ｚ
Ｄ２……第２のツエナーダイオード。 FIG. 1 is a circuit diagram of an embodiment of the present invention according to claim 1, FIG. 2 is a block diagram showing the configuration of an embodiment of the present invention according to claim 2, and FIGS. 3 and 4 are conventional circuit diagrams. FIG. 2 is a circuit diagram of the CPU reset circuit of FIG. Explanation of symbols, 1... CPU, 2... CPU reset circuit, 3... detection circuit, 4... load control circuit, Q1... first transistor, Q2... second transistor, RST... reset terminal , VDD
...First power line, VCC...Second power line, V1...First reference value, V2...Second reference value, ZD1...First Zener diode, Z
D2...Second Zener diode.

Claims

[Claims for Utility Model Registration] (1) A first Zener diode whose Zener voltage is set to a first reference value is connected between the base of the first transistor whose emitter is grounded and the first power supply line. a base of a second transistor whose cathode side is connected to the first power supply line side, whose emitter is connected to a second power supply line that is the power supply of the CPU, and whose collector is grounded via a resistor; A resistor and a second Zener diode whose Zener voltage is defined as a second reference value are connected in series between the collector of the first transistor, and the anode side of the second Zener diode is connected to the collector of the first transistor. The collector of the second transistor is connected to the collector side of the first transistor, and the collector of the second transistor is connected to the collector of the second transistor.
A CPU reset circuit configured to be connected to a reset terminal of U, wherein the voltage levels of the first power line and the second power line exceed the first reference value and the second reference value, respectively. If the period exceeds the above CPU
Outputs a signal voltage to the reset terminal of the CPU.
Then, after performing the reset, necessary signal processing is performed, while the voltage level of the first power supply line is
or when the voltage level of the second power supply line falls below the second reference value, stop outputting the signal voltage to the reset terminal of the CPU, A CPU reset circuit, characterized in that the CPU is configured to stop signal processing operations. (2) a detection circuit having a pyroelectric element that detects heat rays emitted from the human body; a CPU having a reset terminal that processes signals from the detection circuit;
a load control circuit that performs necessary control operations upon receiving the signal; a first power line that supplies power to the detection circuit and the load control circuit; a second power line that supplies power to the CPU; 1st and 2nd
, and during a period in which the voltage levels of the first power supply line and the second power supply line exceed the first reference value and the second reference value, respectively, the reset terminal of the CPU is After performing a reset, the CPU processes the signal from the detection circuit to control the load control circuit to perform necessary control.
If the voltage level of the power supply line falls below the first reference value, or if the voltage level of the second power supply line falls below the second reference value, a signal is sent to the reset terminal of the CPU. 1. A hot wire type detector, comprising: a CPU reset circuit that stops the signal voltage output of the CPU and stops the signal processing operation of the CPU.