红外温度计显示及控制电路设计

摘 要

为小范围空间内的温度进行测量和控制，本文设计了一种利用红外温度计显示及控制电路，在论文中主要采用了红外温度传感器对控制器部分的温度进行采集 ，将非电量信号转换为电信号，转换后的电信号再进入A/D转换器换成数字量，传输给AT89C51单片机处理，以达到对控制对象的温度控制，由LED显示器来显示温度。当温度超出温度控制的范围报警系统会发出报警信号，提醒工作人员进行操作。设计出来的红外温度测量仪对在温室大棚、客厅温度调节、温度快速检测等各方面有重大意义。

关键词：单片机 转换器 显示器

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ABSTRACT

We designed a kind of using infrared thermometer display and control circuit for small area within the space of temperature measurement and control. In this thesis, we mainly used infrared temperature sensor to gather the section temperature controller. It will convert the signals to electricity signal, and be converted to the digital signals by A/D converter. At last, it will transmit to the AT89C51 microcontroller to get processing. Reach for the temperature control of the object, and to display temperature by the LED display. When the temperature exceeds the scope of temperature control the system will alarm issued a warning signal, remind staffs. The successfully developed of the infrared temperature measuring instrument will have the great significance to greenhouse temperature adjustment, awning, sitting room temperature rapid detection.

KEYWORDS：singlechip Converter Monitor

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目录

摘 要 .............................................................................................................................................. 1 ABSTRACT ...................................................................................................................................... 2 目录 .................................................................................................................................................. 3 1. 绪论 ................................................................................................................................... 5

1.1 概述 ................................................................................................................................... 5 1.2温度控制的总体设计和思路 ............................................................................................. 6 1.3系统设计 ............................................................................................................................ 7 2.温度控制电路的设计 ................................................................................................................ 9

2.1 温度传感器的选择 ........................................................................................................... 9

2.1.1红外传感器的工作原理 ........................................................................................ 9 2.1.2 P7187热释电红外传感器工作原理 .................................................................... 9 2.2传感器放大电路及补偿电路的设计 ............................................................................... 10 2.3 A/D转换器的选择 .......................................................................................................... 12

2.3.1 TLC549参数介绍 ................................................................................................ 12 2.3.2 TLC549工作原理 ................................................................................................ 13 2.4单片机AT89C51的结构和原理 ..................................................................................... 14

2.4.1 单片机型号的选择 ............................................................................................. 14 2.4.2 AT89C51的主要性能包括 .................................................................................. 14 2.4.3 AT89C51单片机主要特性 ................................................................................... 15 2.5显示系统及接口电路设计 .............................................................................................. 18

2.5.1数字显示器的选择 .............................................................................................. 18 2.5.2 LED工作原理及选型 .......................................................................................... 18 2.5.3 74LS147译码器的选择 ...................................................................................... 19 3.5.4 LED显示电路 ...................................................................................................... 20 2.6报警电路 .......................................................................................................................... 21 2.7 MOC3061控制电路 .......................................................................................................... 22

2.7.1控制通道的器件选择 .......................................................................................... 22 2.7.2 MOC3061的功能与结构 ...................................................................................... 22 2.7.3 MOC3061控制电路 .............................................................................................. 23 2.8键盘和时钟、复位电路 .................................................................................................. 24

2.8.1键盘输入 .............................................................................................................. 24 2.8.2键盘和时钟、复位电路 ...................................................................................... 25 3.9 MAX232通信电路 ............................................................................................................ 27

3.9.1单片机与PC通信的意义 .................................................................................... 27 3.9.2 MAX232芯片实现单片机与PC通信 .................................................................. 27 3.9.3 MAX232通信电路 ................................................................................................ 27 3.10 电源电路 ........................................................................................................................ 28 3.软件流程图的设计 ..................................................................................................................... 29

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3.1概述 .................................................................................................................................. 29

3.1.1软件功能分析 ...................................................................................................... 29 3.1.2系统时钟周期的设定 .......................................................................................... 29 3.2主程序功能 ...................................................................................................................... 30 3.3 T0中断服务程序 ............................................................................................................ 30 3.4子程序 ............................................................................................................................... 31

3.4.1给定值的计算程序 .............................................................................................. 31 3.4.2采样子程序 .......................................................................................................... 31 3.4.3数字滤波子程序 .................................................................................................. 31 3.4.4 PID算法程序 ...................................................................................................... 35 3.4.5温度标度转换 ...................................................................................................... 35 3.4.6 LED显示子程序 .................................................................................................. 36

4. 结论........................................................................................................................................... 40 5. 经济分析报告 ........................................................................................................................... 41 致 谢 .............................................................................................................. 错误!未定义书签。 参考文献......................................................................................................................................... 43

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