课程设计
简易直流数字电压表
设计题目： 简易直流数字电压表 专 业： 电气工程及其自动化 年 级： 08级 学 号： 200895014041 姓 名： 赵晓刚
目 录
引言·······························································1 1 设计目的和要求···············································3
1.1 设计目的························································3 1.2 设计内容及要求··················································3
2 数字电压表的基本原理·········································3
2.1 数字电压表组成电路··············································3 2.2 系统功能························································4
3 元器件的介绍··················································5
13.1 3A/D转换器MC14433的介绍·····································5
23.2 MC14433引脚功能说明···········································8 3.3 七段锁存—译码—驱动器MC4511的介绍···························10 3.4 七路达林顿驱动器阵列MC1413的介绍·····························12 3.5 高精度低漂移能隙基准电源MC1403的介绍························12
4 课程设计调试的要点··········································12
4.1 电路调试·······················································12 4.2 功能调试·······················································13
5 课程设计器材和供参考选择的元器件··························13 6 课程设计报告结论············································13 6.1 按设计内容要求整理实验数据及调试中的波形·······················14
6.2 画出设计内容中的电路图、接线图·································15 6.3 总结设计数字电压表的体会·······································15
引言
传统的模拟式（即指针式）电压表已有100多年的发展史，虽然不断改进与完善，仍无法满足现代电子测量的需要，数字电压表自1952年问世以来，显示强大的生命力，现已成为在电子测量领域中应用最广泛的一种仪表。
数字电压表简称DVM（Digital Voltmeter），它是采用数字化测量技术，把连续的模拟量（直流输入电压）转换成不连续、离散的数字形式并加以显示的仪表。智能化数字电压表则是最大规模集成电路（LSI）、数显技术、计算机技术、自动测试技术（ATE）的结晶。一台典型的直流数字电压表主要由输入电路、A/D转换器、控制逻辑电路、计数器（或寄存器）、显示器，以及电源电路等级部分组成，如下图1-1所示：
图1-1 直流数字电压表的基本方框图
其中A/D转换器是数字电压表的核心，ux表示其输入。它的数字输出可由打印机记录，也可以送入计算机进行数据处理。数字电压表与指针式电压表相比具有以下特点：
（1）显示清晰、直观、读数准确
传统的模拟式电压表必须借助指针和刻度盘进行读数。在读书过程中不可避 免地会引入人为的测量误差（例如视差），并且还容易造成视觉疲劳，数字电压表则采用了先进的数显技术，使显示结果一目了然，只要仪表不发生跳数现象，测量结果就是唯一的，不仅保证了读书的客观性与准确性，还符合人们的读数习惯，能够缩短读书和记录的时间。 （2） 显示位数多
位数是表征数字电压表性能的一个最基本的参量。数字电压表显示位数通常
1111231为2位~8位。具体讲，有2位、3位、3位、3位、3位、4位、4位、
22234221111315位、5位、6位、6位、7位、8位共14种。国外最近还推出8位和10222242位数字仪表。
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