基于单片机的数字温度计设计毕业论文.doc

摘要 随着国民经济的发展，人们需要对各种加热炉、热处理炉、反应炉和锅炉中温度进行监测和控制。采用单片机来对他们控制不仅具有控制方便，简单和灵活性大等优点，而且可以大幅度提高被控温度的技术指标，从而能够大大的提高产品的质量和数量。在日常生活及工业生产过程中，经常要用到温度的检测及控制，温度是生产过程和科学实验中普遍而且重要的物理参数之一。在生产过程中，为了高效地进行生产，必须对它的主要参数，如温度、压力、流量等进行有效的控制。温度控制在生产过程中占有相当大的比例。温度测量是温度控制的基础，技术已经比较成熟。传统的测温元件有热电偶和二电阻。而热电偶和热电阻测出的一般都是电压，再转换成对应的温度，这些方法相对比较复杂，需要比较多的外部硬件支持。我们用一种相对比较简单的方式来测量。我们采用美国DALLAS半导体公司继DS18B20之后推出的一种改进型智能温度传感器DS18B20作为检测元件，温度范围为-55~125 oC,最高分辨率可达0.0625 oC。DS18B20可以直接读出被测温度值，而且采用三线制与单片机相连，减少了外部的硬件电路，具有低成本和易使用的特点。 本文介绍一种基于AT89C51单片机的一种温度测量及报警电路,该电路采用DS18B20作为温度监测元件，测量范围0℃-～+100℃，使用LED模块显示，能设置温度报警上下限。该电路设计新颖、功能强大、结构简单。 关键词：温度测量；DS18B20；AT89C51  Abstract Along with national economy development, the people need to each heating furnace、the heat-treatment furnace、in the reactor and the boiler the temperature carry on the monitor and the control. Not only uses the monolithic integrated circuit to come to them to control has the control to be convenient, simple and flexibility big and so on merits, moreover may enhance large scale is accused the temperature technical specification, thus can big enhance the product the quality and quantity.In daily life and industrial production process, often used in the detection and control of temperature, temperature is the production process and scientific experiments in general and one of the important physical parameter. In the production process, in order to efficiently carry out the production, to be its main parameters, such as temperature, pressure, flow control, etc... Temperature control in the production process of a large proportion. Temperature measurement is the basis of temperature-controlled, more mature technology.Traditional thermocouple and temperature components are the second resistor.The thermocouple and thermal resistance are generally measured voltage, and then replaced by the corresponding temperature, these methods are relatively complex, requiring a relatively large number of external hardware s