摘要：随着科技的不断发展，不论是在日常生活中还是在工业生产中，人们对数字电压表的精度、稳定性、速度都有着越来越高的要求。为此，本文运用单片机技术，设计了一款性能稳定、高精度的数字电压表。该电压表由单片机控制系统、A/D转换模块、显示模块组成，A/D转换模块实现对采样电压值数字化转换，转换后的电压值经单片机处理后通过LED显示器显示，该电压表可实现0到5V、精度为0.01V电压的测量。本文设计了单片机控制电路、A/D转换电路及显示电路，并在Proteus上进行软硬件仿真，仿真结果验证了软硬件设计的正确性，该电压表设计方案的实现，具有一定的实用性。56952

毕业论文关键词：数字电压表，A/D转换，AT89C52，显示

Abstract：There are increasing high requirements for the accuracy, stability and speed of the digital voltmeter in both our daily life and industrial production with the ever-changing development of science and technology, for which, this thesis apply the technology of single-chip microcomputer to design a digital voltmeter of stable quality and high accuracy. This digital voltmeter is made up of the single-chip microcomputer controlled system, A/D transformational module and the displaying module. The A/D transformational module realizes the digital transformation of the sampling voltage value. The transformed sampling voltage value will be displayed by the LED screen after the processing of the single-chip microcomputer. This voltmeter can realize the measurement of the voltage between 0 to 5V, with the accuracy of 0.02V. This paper designs the control circuit for the single-chip microcomputer, A/D transformational circuit and display circuit. The result of the simulation of software and hardware on Proteus proves the correctness of the design of them. The realization of the design of this voltmeter has practicality to some degree.

Keywords：digital voltmeter, A/D converter, AT89C52, displaying module 

目录

1 绪论 4

1.1课题背景 4

1.2设计的目的和意义 5

2 总体方设计案 6

2.1设计原理及要求 6

2.1.1数字电压表的实现原理 6

2.1.2数字电压表的设计要求 6

2.2设计方案 7

3 硬件电路设计 7

3.1主控芯片的选择 7

3.2 A/D转换模块ADC0808 8

3.2.1 ADC0808主要特性 8

3.2.2逐次逼近转换原理 10

3.2.3 ADC0808的内部结构及工作流程 10

3.3  LED数码显示设计 11

3.3.1 LED的基本结构 11

3.3.2 LED显示器的选择 11

3.3.3 LED显示器与单片机接口设计 12

3.4 锁存器74LS373的硬件设计 13

3.5 总体电路设计 14

4 系统软件设计 14

4.1主程序设计 14

4.2 子程序设计 15

4.2.1 A/D转换子程序 15

4.2.2中断显示子程序 16

5 系统仿真 AT89C52单片机的数字电压表设计+程序+电路图:http://www.youerw.com/zidonghua/lunwen_61546.html