毕业设计--数字电压表的设计--论文.doc

数字电压表的设计 摘 要 在电气测量中，电压是一个很重要的参数。如何准确地测量模拟信号的电压值，一直是电测仪器研究的内容之一。 本文介绍一种以89C52单片机为主要控制器件,采用ICL7135高精度、双积分A/D转换器的一种电压测量电路。主要包括硬件电路设计和系统程序设计。硬件电路主要包括数据采集模块，数据处理模块（单片机系统）和输出显示模块。在数据采集模块中，主要是在对电压信号采样前，用放大器进行预处理，后采用双积型A/D转换器ICL7135进行转换，将转换得到的信号送入单片机中。在数据处理模块（单片机系统）中，主要是通过89C52单片机将A/D转换后得到的信号进行处理。显示模块中，采用LCD液晶模块1602显示。在软件设计方面，主要包括初始化程序，中断程序，档位选择程序和显示程序等几个子程序模块。 通过上面这个系统可实现测量直流电压范围0-±200伏，可实现200伏档，20伏档，2伏档，200毫伏档间自动换档，使用LCD液晶显示测量电压，并且当测量电压高于±200伏时，液晶屏显示过量程信号。 正文着重给出了软硬件系统的各部分电路，介绍了双积分电路的原理，89C52的特点，ICL7135的功能和应用，LCD1602的功能和应用。该电路设计新颖、功能强大、可扩展性强。适用于人们的日常生活及工农业生产中用于电压的检测。 关键字：电压测量，自动换档，双积分A/D转换器，1602液晶模块 THE DESIGN OF DIGITAL VOLTMETER ABSTRACT The measurement of electrical voltage is a very important parameter. How to accurately measure the voltage of the analog signal is one of the elements of electrical measurement. The?paper?introduced one kind?new? method about digital voltmeter that take the Micro Controller Unit 89C52 as the primary control component and using high-precision ,double integral A/D converter ICL7135 circuit?. Mainly?included the design of the hardware electric circuit and the design of the software system. Hardware circuit including data acquisition module, data-processing module (MCU System) and output display module. In data acquisition modules, before sample the voltage signal, pretreatment with amplifier, after through double integrating A / D converter ICL7135 conversion, the signal has been converted was take into the Micro Controller Unit 89C52. In the data processing module (MCU System), mainly through the Micro Controller Unit 89C52 process the signal which after A / D converter. In the display module, using LCD module 1602 display the voltages. In software system design, including the initialization procedures, the interrupt procedures, the selection of the range of voltage procedures and the display procedures, and several other subroutine modules. Through this system can achieve the above measure DC voltage range of 0 - ± 200 v, automatic c