CN103471734A

CN103471734A - Digital thermometer

Info

Publication number: CN103471734A
Application number: CN201310408612XA
Authority: CN
Inventors: 王火明
Original assignee: KUNSHAN XINJINFU PRECISION ELECTRONICS Co Ltd
Current assignee: KUNSHAN XINJINFU PRECISION ELECTRONICS Co Ltd
Priority date: 2013-09-10
Filing date: 2013-09-10
Publication date: 2013-12-25

Abstract

The invention discloses a digital thermometer. The digital thermometer comprises a single-chip microcomputer, a temperature measurement circuit, an alarm circuit, an LED displayer and a button, wherein the temperature measurement circuit, the alarm circuit, the LED displayer and the button are connected with the single-chip microcomputer respectively. The digital thermometer which is based on the single-chip microcomputer has obvious advantages, can be used for realizing temperature data collection and display conveniently and quickly, and is convenient to use due to the fact that an upper limit alarm temperature and a lower limit alarm temperature can be set at will according to requirements; the digital thermometer has the advantages of being high in measurement accuracy, broad in measurement range, high in sensitivity, low in energy consumption, strong in anti-jamming capability and the like.

Description

A kind of digital thermometer

Technical field

The present invention relates to the temperature measurement technology field, be specifically related to a kind of digital thermometer.

Background technology

Along with China is information-based and industrialized high speed development, the people's life and the temperature of environment are closely bound up, need to measure in real time temperature in industrial processes, also be unable to do without the measurement of temperature in agricultural production, measuring method and the device of therefore studying temperature have great importance.The traditional thermal resistance thermometer, take thermistor as temperature-sensing element (device), have advantages of that cost is low, but reliability is relatively poor, and the thermometric accuracy is low, while follow-up signal treatment circuit, and detection system also has certain error.

Summary of the invention

Goal of the invention: for the deficiencies in the prior art, the purpose of this invention is to provide a kind of digital thermometer, volume is little, compact conformation, safe and reliable, cost is low.

Technical scheme: in order to realize the foregoing invention purpose, the technical solution used in the present invention is: a kind of digital thermometer comprises single-chip microcomputer and connected temperature measurement circuit, warning circuit, LED show and button respectively with it.

Described single-chip microcomputer is the AT89S52 series monolithic, and is connected with reset circuit, clock circuit, guarantees the normal operation of single-chip microcomputer; This kind of single-chip microcomputer has low voltage power supply and the characteristics such as volume is little, and four ports only need two mouths just can meet the design needs of Circuits System, and the design that is well suited for the portable hand-holding type product is used system can use two whose power supplieds.

Described temperature sensor is DS18B20, measurement range is-55～+ 125 degrees centigrade, is programmed for 9～12 conversion accuracies, 0.0625 degree centigrade of thermometric resolution, the alarm temperature that resolution setting parameter and user set is stored in EEPROM, after power down, still preserves.16 bit digital quantity mode serial outputs of sign extended for dut temperature; Its working power both can be introduced at far-end, also can adopt the parasite power mode to produce; Single-chip microcomputer only needs a root port line just can communicate by letter with many DS18B20, and the port taken is less, can save a large amount of lead-in wires and logical circuit.Therefore form a temp measuring system with it, circuit is simple, convenient.

Described LED is shown as 4 LED charactrons, shows 2 integers, 1 decimal, 1 unit.

Also comprise expanded circuit, be connected with single-chip microcomputer, can carry out data storage and exchange.

Beneficial effect: SCM Based digital thermometer provided by the invention is with the obvious advantage, can realize easily temperature acquisition and demonstration, and can set arbitrarily as required the bound alarm temperature, easy-to-use, have that measuring accuracy is high, measurement range is large, highly sensitive, low, the advantage such as antijamming capability is strong consumes energy.

The accompanying drawing explanation

Fig. 1 is the theory diagram of digital thermometer.

Embodiment

Further illustrate the present invention below in conjunction with accompanying drawing, should understand these embodiment only is not used in and limits the scope of the invention for the present invention is described, after having read the present invention, those skilled in the art all fall within the application's claims limited range to the modification of various equivalents of the present invention.

As shown in Figure 1, digital thermometer by single-chip microcomputer and with it respectively connected temperature measurement circuit, warning circuit, LED show and button, also comprise reset circuit and clock circuit, with single-chip microcomputer, be connected, guarantee the normal operation of single-chip microcomputer; Expanded circuit, be connected with single-chip microcomputer, can carry out data storage and exchange.

Described single-chip microcomputer is the AT89S52 series monolithic.

Described temperature sensor is DS18B20.

Principle of work of the present invention is: the user is by the key-press input limit value of reporting to the police, temperature measurement circuit is uploaded to single-chip microcomputer by the temperature sensor image data, and single-chip microcomputer, after Treatment Analysis, outputs to laser-emitting diode, when measured temperature is greater than the preset alarm limit value, drive warning circuit to report to the police.The setting of expanded circuit can realize the storage of measured temperature data, and can be transmitted to outer computer.

Claims

1. a digital thermometer is characterized in that: comprise single-chip microcomputer and with it respectively connected temperature measurement circuit, warning circuit, LED show and button.

2. digital thermometer according to claim 1, it is characterized in that: described single-chip microcomputer is the AT89S52 series monolithic, and is connected with reset circuit, clock circuit.

3. digital thermometer according to claim 1, it is characterized in that: described temperature sensor is DS18B20.

4. digital thermometer according to claim 1, it is characterized in that: described LED is shown as 4 LED charactrons, shows 2 integers, 1 decimal, 1 unit.

5. digital thermometer according to claim 1, is characterized in that: also comprise expanded circuit, be connected with single-chip microcomputer, can carry out data storage and exchange.