PDF《毕业设计开题报告》

再用数字频率计 测量出电路的频率值,从而表示被测电压的大小.这种转换器具有良好的精度、 线性和积分输入特性,抗干扰能力强,而且信号便于远传等特点.此外,它的应 用电路简单,外围元件性能要求不高,对环境的适应能力强,与单片机的接口简 单. 本设计在参阅了大量前人设计的数字电压表的基础上, 利用单片机技术结合 V/F 转换芯片 LM331 以及采用模拟开关 CD4051 构建了一个测量范围达 0-750V 且具有自动量程切换功能和过压保护的交直流数字电压表. 本文首先简要介绍了 积分式数字电压表的主要组成部分及原理, 然后详细介绍了硬件系统和软件系统 的设计,并给出了硬件电路的各部分电路的设计及原理以及软件算法. 关键词 电压测量;

自切换;

LM331;

模拟开关;

单片机 I 积分式数字电压表 INTEGRAL DIGITAL VOLTMETER ABSTRACT With the development of electronical scientific technology, electronical measurement became a technic that everyone of engaging electronical had to master it. What'

s more, the precision is higher and higher and, the function is more and more powerful, and voltage'

s measurement is best important. At the same time as the rapid development of microelectronics technology and the emergence of ultra-large-scale integrated circuits ,In particular the emergence of MCU, is causing the field of measurement and control instruments of the new technological revolution. V/F-A/D converter is an integral, Ux measured voltage line through the points after the change in the output voltage, Control a oscillator, Produce With a measured voltage proportional to the frequency value;

Use of d........