摘要：在电量的测量中，电压、电流和频率是最基本的三个被测量。其中，电压量的测量最为常见。随着电子技术的发展，用指针式万用表测量小幅度直流电压已经显得有些不太方便。另外，由于数字式仪器具有读数准确方便、精度高、误差小、灵敏度高和分辨率高、测量速度快等特点而倍受用户青睐，数字式电压表就是基于这种需求而发展起来的。本文将介绍一种由数字电路以及单片机构成的双路显示数字电压表的设计。
本设计在传统数字电压表（单路）的基础上加于扩展和改进，设计制作一个以单片机为核心的双路显示数字电压表，能够巡回采集两路直流电压的数据，并进行信号分时处理及标度变换，同时显示两路电压，实现双路直流电压的测量。该电压表不仅能完成简单的单路直流电压的测量，而且完成双路电压的同时测量，便于双路电压的比较，减小因单路分别测量带来的误差和影响，能够应用于需要同时测量比较双路电压的多种环境。
该电压表主要由三个模块组成：A/D转换模块、数据处理模块及电压显示模块。A/D转换模块采用ADC0832芯片,数据处理模块采用STC89C52单片机，
电压显示模块采用LCD1602液晶显示屏。该电压表测量电压类型是直流,测量范围是0-20V，误差范围是0-0.10V。
关键词：STC89C52 ；ADC0832；LCD1602；数字电压表
ABSTRACT：In the measurement of electricity, voltage, current and frequency is the most basic of the three measurements.Among them, the amount of voltage measurement is the most common. With the development of electronic technology, the small magnitude of the DC voltage measured by multimeter has seemed to be somewhat inconvenient. In addition, because the digital instrument readings accurate and convenient, high precision, the error is small, high sensitivity and high resolution, fast measurement speed and highly popular to users, the digital voltmeter is developed based on this demand. This article describes the design of a digital circuit and microcontroller consisting of dual display digital voltmeter.
The design in the traditional digital voltmeter (single) on the basis of the expansion and improvement, design a microcontroller as the core of the dual display digital voltmeter to be able to tour to collect data of the two DC voltage and the signal time-sharing processing and scale conversion, while the voltage of the two dual DC voltage measurement. The voltmeter is not only able to complete a simple single-channel DC voltage measurements, and complete dual voltage measurement at the same time, to facilitate the comparison of dual-voltage, reduce the error caused by the single measurement and influence, can be used need to measuring a variety of more dual voltage environment.
The voltmeter consists of three modules: the A / D converter module, the data processing module and voltage display module. A / D converter module using ADC0832 chip, data processing module STC89C52 microcontroller, voltage display module using the LCD1602 LCD display. The voltmeter measure the voltage type DC, the measuring range is 0-20V, the error range is 0-0.10V.
Key words: STC89C52 ；ADC0832；LCD1602；Digital Voltmeter
