电容容量的精确测量.docVIP

摘要 本设计主要研究电容容量的测量。电容在电子线路中得到广泛的应用，它的容量大小对电路的性能有着重要的作用，对推动科技及生产发展均有重要的应用价值。在测量领域，电容容量是一个基本的测量对象。电容容量测量近年来得到大范围的推广应用，国内外越来越多的人研究电容测量技术，努力提高其精度。电容测量电路的设计是为了方便准确的测量电容性能。 Abstract This design mainly research capacitance measurement. Capacitor in the electronic circuit is widely used, its size on the performance of the circuit has an important role in promoting the development of technology and production have important applications. In the measurement, capacitance measurement is a basic object. Capacitance measurements in recent years been promoting a wide range of applications, More and more people at home and abroad study capacitance measurement techniques, efforts to improve its accuracy. Capacitance measuring circuit is designed to facilitate the accurate measurement of capacitance performance. Now, with the microcontroller technology continues to mature, with a single chip to measure the capacitance will be more accurate and intelligent. This design uses a pulse counting method to measure the capacitance. Pulse counting method is to convert the capacitor C through the RC three-point oscillation into frequency signal f, so put analog to digital, and then into the single chip count. After the data processing and a series of calculated operations find the capacitance C, and sent to display. Capacitance measurements in agriculture, materials, machinery, process control and pipeline detection have wide application areas, and for promoting the development of production technology have important application value. Keywords Capacitance; Measure; 555 oscillator; single chip microcomputer 目 录 摘要 I Abstract II 第1章 绪论 1 1.1 课题背景 1 1.2 研究现状 1 1.3 发展趋势 3 1.4 本论文的主要工作 4 第2章 电容容量测量的原理和设计要点 5 2.1 电容的基本知识 5 2.2电容测量原理简介 6 2.3 本论文的测量原理 7 2.4本论文的设计要点 7 2.5本章小节 8 第3章 电容测量电路设计 9 3.1总体设计 9 3.2 RC振荡电路设计 9 3.2.1 555振荡电路 9 3.2.2 电容分档测量电路 12 3.2.3测量电路中电阻的选择 13 3.3 数字部分电路设计 14 3.3.1 单片机的选择 14 3.3.2 单片机时钟电路设计 18 3.3.3 单片机的复位电路设计 20 3.3.4 单片机的定时器/计数器设置 21 3.4 各接口电路设计 24 3.4.1 RC振