CN202995612U

CN202995612U - Singlechip reset circuit

Info

Publication number: CN202995612U
Application number: CN 201220689337
Authority: CN
Inventors: 简书杰
Original assignee: QuanZhou HaoJie Information Technology Development Co Ltd
Current assignee: QuanZhou HaoJie Information Technology Development Co Ltd
Priority date: 2012-12-13
Filing date: 2012-12-13
Publication date: 2013-06-12
Anticipated expiration: 2022-12-13

Abstract

The utility model relates to the field of electronics, and provides a singlechip reset circuit capable of resetting initial settings when the singlechip is halted or the program is at an error state or the power source voltage is too low. The singlechip reset circuit includes a direct current power source, an active monitoring circuit, a power source voltage detection circuit, a time setting circuit and a trigger circuit, wherein the active monitoring circuit is an MAX6303ESA chip; the direct current power source is connected with a power source end of the power source voltage detection circuit and an eighth pin of the MAX6303ESA respectively; an output end of the power source voltage detection circuit is connected with a first pin of the MAX6303ESA chip; the time setting circuit is connected with a third pin and a fourth pin of the MAX6303ESA chip; the trigger circuit is connected with the sixth pin of the MAX6303ESA chip; a seventh pin of the MAX6303ESA chip is used for reset output and is connected with the singlechip; and a fifth pin of the MAX6303ESA chip is grounded.

Description

A kind of reset circuit of SCM

Technical field

The utility model relates to electronic applications, particularly a kind of reset circuit of SCM.

Background technology

Be widely used in the fields such as industrial automation production, process control, GPS positioning system along with single-chip microcomputer, so the reliability requirement of single-chip microcomputer is more and more higher.Yet in the use procedure of single-chip microcomputer, the too low situation of supply voltage can occur, make Single Chip Microcomputer (SCM) system operation wadding disorderly, even system itself be caused damage, so reset circuit of SCM is part and parcel very in single-chip microcomputer.The reset circuit that adopts at present comparatively complexity and use can be restricted.In addition, starve interference because single-chip microcomputer also usually is subject to external electromagnetic field in the course of the work, cause the race of Single Chip Microcomputer (SCM) system program to fly, be absorbed in endless loop, thereby cause Single Chip Microcomputer (SCM) system to work on, even produce unforeseen serious consequence.

Summary of the invention

Therefore, for above-mentioned problem, the utility model proposes a kind of single-chip microcomputer that makes and crashing or program enters abnormality or supply voltage recovers single-chip microcomputer to the reset circuit of SCM of initial setting up when too low.

for solving this technical matters, the utility model is taked following scheme: a kind of reset circuit of SCM, comprise direct supply, active supervisory circuit, voltage detection circuit, time set circuit and trigger circuit, described active supervisory circuit is the MAX6303ESA chip, described direct supply is connected with MAX6303ESA chip the 8th pin with the power end of voltage detection circuit respectively, described voltage detection circuit output terminal connects MAX6303ESA chip the 1st pin, described time set circuit connects MAX6303ESA chip the 3rd, the 4th pin, described trigger circuit connect MAX6303ESA chip the 6th pin, described MAX6303ESA chip the 7th pin preset output is connected with single-chip microcomputer, described MAX6303ESA chip the 5th pin ground connection.

Further, described voltage detection circuit comprises adjustable resistance R1 and R2, and described adjustable resistance R1 one end connects direct supply, and the other end is connected with MAX6303ESA chip the 1st pin with adjustable resistance R2 one end, described adjustable resistance R2 other end ground wire.

Further, described time set circuit comprises capacitor C 1, C2 and C3, described capacitor C 1 one ends connect MAX6303ESA chip the 3rd pin, the other end is connected with ground wire with capacitor C 2 one ends, capacitor C 3 one ends, and described capacitor C 2 other ends are connected with MAX6303ESA chip the 4th pin with capacitor C 3 other ends.

by adopting the aforementioned techniques scheme, the beneficial effects of the utility model are: by with voltage detection circuit, time set circuit and trigger circuit connect and compose a reset circuit of SCM with the MAX6303ESA chip respectively, make when single-chip microcomputer when outside ferroelectric carried out reading and writing data, might cause ferroelectric reading and writing data mistake or loss if supply voltage is unstable, just need voltage detection circuit that supply voltage is monitored this moment, if in the situation of brownout, MAX6303ESA chip the 7th pin preset output low level makes monolithic processor resetting, when the MAX6303ESA chip works, within the time regularly (by C1, C2, C3 determines), if trigger circuit are received the signal of single-chip microcomputer, the 7th pin preset output of MAX6303ESA chip keeps original level high level output, if do not receive the signal of single-chip microcomputer, MAX6303ESA chip the 7th pin preset output output low level makes monolithic processor resetting, thereby single-chip microcomputer is being crashed or program enters abnormality or supply voltage recovers single-chip microcomputer to initial setting up when too low.

Description of drawings

Fig. 1 is the circuit theory diagrams of the utility model embodiment.

Embodiment

Now with embodiment, the utility model is further illustrated by reference to the accompanying drawings.

with reference to figure 1, preferred a kind of reset circuit of SCM of the present utility model, comprise direct supply VDD, active supervisory circuit, voltage detection circuit 1, time set circuit 2 and trigger circuit 3, described active supervisory circuit is the MAX6303ESA chip, described direct supply VDD is connected with MAX6303ESA chip the 8th pin with the power end of voltage detection circuit 1 respectively, described voltage detection circuit 1 output terminal connects MAX6303ESA chip the 1st pin, described time set circuit 2 connects MAX6303ESA chip the 3rd, the 4th pin, described trigger circuit 3 connect MAX6303ESA chip the 6th pin, described MAX6303ESA chip the 7th pin preset output is connected with single-chip microcomputer, described MAX6303ESA chip the 5th pin ground connection, described voltage detection circuit 1 comprises adjustable resistance R1 and R2, described adjustable resistance R1 one end connects direct supply VDD, the other end is connected with MAX6303ESA chip the 1st pin with adjustable resistance R2 one end, described adjustable resistance R2 other end ground wire, described time set circuit 2 comprises capacitor C 1, C2 and C3, described capacitor C 1 one ends connect MAX6303ESA chip the 3rd pin, the other end and capacitor C 2 one ends, capacitor C 3 one ends are connected with ground wire, described capacitor C 2 other ends are connected with MAX6303ESA chip the 4th pin with capacitor C 3 other ends.

the utility model passes through voltage detection circuit, time set circuit and trigger circuit connect and compose a reset circuit of SCM with the MAX6303ESA chip respectively, make when single-chip microcomputer when outside ferroelectric carried out reading and writing data, might cause ferroelectric reading and writing data mistake or loss if supply voltage is unstable, just need voltage detection circuit that supply voltage is monitored this moment, if in the situation of brownout, MAX6303ESA chip the 7th pin preset output low level makes monolithic processor resetting, when the MAX6303ESA chip works, within the time regularly (by C1, C2, C3 determines), if trigger circuit are received the signal of single-chip microcomputer, the 7th pin preset output of MAX6303ESA chip keeps original level high level output, if do not receive the signal of single-chip microcomputer, MAX6303ESA chip the 7th pin preset output output low level makes monolithic processor resetting, thereby single-chip microcomputer is being crashed or program enters abnormality or supply voltage recovers single-chip microcomputer to initial setting up when too low.

Although specifically show and introduced the utility model in conjunction with preferred embodiment; but the those skilled in the art should be understood that; within not breaking away from the spirit and scope of the present utility model that appended claims limits; can make a variety of changes the utility model in the form and details, be protection domain of the present utility model.

Claims

1. reset circuit of SCM, it is characterized in that: comprise direct supply, active supervisory circuit, voltage detection circuit, time set circuit and trigger circuit, described active supervisory circuit is the MAX6303ESA chip, described direct supply is connected with MAX6303ESA chip the 8th pin with the power end of voltage detection circuit respectively, described voltage detection circuit output terminal connects MAX6303ESA chip the 1st pin, described time set circuit connects MAX6303ESA chip the 3rd, the 4th pin, described trigger circuit connect MAX6303ESA chip the 6th pin, described MAX6303ESA chip the 7th pin preset output is connected with single-chip microcomputer, described MAX6303ESA chip the 5th pin ground connection.

2. a kind of reset circuit of SCM according to claim 1, it is characterized in that: described voltage detection circuit comprises adjustable resistance R1 and R2, described adjustable resistance R1 one end connects direct supply, the other end is connected with MAX6303ESA chip the 1st pin with adjustable resistance R2 one end, described adjustable resistance R2 other end ground wire.

3. a kind of reset circuit of SCM according to claim 1, it is characterized in that: described time set circuit comprises capacitor C 1, C2 and C3, described capacitor C 1 one ends connect MAX6303ESA chip the 3rd pin, the other end is connected with ground wire with capacitor C 2 one ends, capacitor C 3 one ends, and described capacitor C 2 other ends are connected with MAX6303ESA chip the 4th pin with capacitor C 3 other ends.