摘要石英晶体微天平是通过操控石英晶体的压电效应，把附着于石英电极表层的待测物体的质量变化转化为可测量的频率信号的精密检测装置。石英晶体具备较高的频率，并在其表层附着微小物质质量时，就足以产生频率的变化。所以它可以用来检测出极小的质量变化，检测的灵敏度从微克至纳克级。鉴于石英晶体的这一特征，QCM经常被应用在生物分间的相互作用、蛋白质等材料的表层吸附、电化学和空气环境质量检验等多个领域。83919

本文首先对QCM的研究背景和国内外发展现状进行探讨，然后用通俗易懂的语句描述怎样对QCM数据进行简化但又保证研究精度要求的定量分析。通过对芯片型号的选择，由信号采集电路和滤波电路建立起石英晶体微天平的测量电路。最后对信号频率加以改变，通过仿真采集数据绘制幅频和相频频率特性曲线，以此验证出设计的QCM检测电路是正确有效的。

毕业论文关键词：石英晶体微天平；谐振频率；检测电路；Multisim仿真

毕业设计说明书外文摘要

Title    Design of detection circuit for quartz crystal micro balance based on Multisim           

Abstract Quartz Crystal Microbalance (QCM) is a piezoelectric effect of quartz crystal, and the viscosity of the liquid adsorbed on the surface of quartz electrode and the change of the mass of the adsorbed substance can be converted into a precision measuring device for the measurement of the frequency signal。 Quartz crystal has a high frequency, and in its surface attached to the quality of small matter, it is enough to produce changes in frequency。 So it can be used to detect very small changes in quality, the detection of the sensitivity from micrograms to the level of。 In view of the characteristics of quartz crystal, QCM is often used in the field of biological interactions, protein and other materials, such as surface adsorption, electrochemical and air environmental quality inspection and other fields。

Firstly, this paper discusses the research background and development status of QCM at home and abroad, and then describes how to simplify the QCM data and to ensure the accuracy of the research。 By selecting the type of the chip, the measuring circuit of the quartz crystal micro balance is built up by the signal collecting circuit and the filter circuit。 At last, the signal frequency is changed, and the amplitude frequency and phase frequency characteristic curves are drawn by simulation, which verifies that the design of QCM detection circuit is correct and effective。 

Keywords：QCM; measuring circuit; piezoelectric effect; design

目   录

1 引言 1

1。1研究背景 1

1。2国内外研究现状 2

1。3 本文的研究内容与主要工作 3

2  基本原理 5

2。1 理论基础 5

2。2 原理简要分析 6

3  QCM等效电路 8

3。1 QCM等效电路模型 8

3。2 QCM谐振频率 9

3。3 分析 13

4  硬件电路的设计 14

4。1 说明 14

4。2 QCM系统的总体结构 14

4。3 QCM信号采集电路设计