基于单片机的数字电压表单元硬件设计毕业论文.doc

基于数字电压表单元硬件设计 Based on digital voltmeter unit hardware design 总 计： 26页 表 格： 1个 插 图： 8 幅 基于数字电压表单元硬件设计 ［摘要］在现代检测技术中,常需用高精度数字电压表进行现场检测,将检测到的数据送入微计算机系统,完成计算、存储、控制和显示等功能。本文中数字电压表的控制系统采用AT89c51单片机,A／D转换器采用ADC0809为主要硬件,实现数字电压表的硬件电路与软件设计。该系统的数字电压表电路简单,所用的元件较少,成本低,调节工作可实现自动化。还可以方便地进行8路A／D转换量的测量,远程测量结果传送等功能。数字电压表可以测量0～5V的8路输入电压值,并在四位LED数码管上轮流显示或单路选择显示Hardware Design of Multi-user Identification Unit Based on the RF IC Electronic Information Engineering Major LI KE Abstract: In the modern examination technology, often needs the high accuracy digit voltmeter to carry on the scene examination, will examine the data sends in the micro computer system, completes functions and so on computation, memory, control and demonstration. In this article the digital voltmeters control system uses at89c51 monolithic integrated circuit, a/D switch uses ADC0809 is the main hardware, realizes the digital voltmeters hardware circuit and the software design. This systems digital voltmeter electric circuit is simple, uses the part are few, the cost is low, the adjustment work may be automated. May also carry on 8 group A/D transformation quantity conveniently the survey, functions and so on long-distance measurement result transmission. The digital voltmeter may survey 0~5V 8 group input voltage value, and demonstrates or the single-channel choice demonstration in turn on four LED nixietubes Key words: Monolithic integrated circuit digit voltmeter A/D transformation 目 录 1 引言 ....................................................................1 1.1 研究的目的和意义 1 1.2 发展历程 1 1.2.1 数字化阶段 1 1.2.2 高精度阶段 1 1.2.3 智能化阶段 ………………………………………………………… ……1 1.3 主要研究内容 2 2 系统的总体设计 ..........................................................2 2.1 系统功能 3 2.2 系统主要技术指标 3 2.3 系统的总体结构 3 3数字电压表单元的硬件设计 ............................................4 3.1 模/数转换ADC0809硬件设计 4 3.1.1 主要性能指标 5 3.1.2 ADC0809引脚功能图 5 3.1.3 ADC0809接口电路的设计 6 3.2 电源电路的设计 8 3.3 看门狗电路的设计 9 3.3.1 X5045芯片简介 9 3.3.2 X5045的工作原理 9 3.3.3 X5045看门狗电