【作者】 张利芬；

【导师】 瞿安连；

【作者基本信息】 华中科技大学 ， 生物医学工程， 2006， 硕士

【摘要】 目前,膜片钳技术已成为现代细胞电生理研究的常规方法。其中,数据采集系统连接着膜片钳前端系统和计算机系统,实现了对膜片钳放大器进行实验控制并对其输出进行数据采集的功能,是检测系统的数据中转枢纽。随着膜片钳技术的推广与应用,膜片钳实验系统的自动化成为必然的发展趋势。而常见的PCI数据采集卡将不能满足实验的要求。为此,我们设计了一种全新的基于USB2.0(Universal Serial Bus 2.0)总线技术和大规模可编程逻辑器件的数据采集系统。该系统引入了FPGA的控制,使得输入输出同步,采样频率从1kHz到350kHz可调;具有4个模拟输出控制通道和8个模拟输入采集通道;采用了数字隔离器件,合理的电源设计方案以及低噪声设计技术和电位器调节以达到较高的精度。本文从系统的方案论证和关键器件选择开始,详尽介绍了基于USB2.0总线技术的全自动膜片钳系统的实验控制和数据采集电路的设计。在描述各个部分的组成和设计思路之后,着重对USB2.0接口电路、复杂控制逻辑、信号调理电路以及混合电路低噪声设计和技术细节进行了讨论。同时,对系统电路在调试过程中遇到的问题和困难以及相应的解决方法做了简要描述,并在结尾部分给出了最终的调试结果和对课题全部工作的总结与展望。更多还原

【Abstract】 Nowadays, Patch-Clamp technique has already become a general method in the field of modern electrophysiological research. Data acquisition system links Patch-Clamp with personal computer, realizes the communication between the data and the control commands.With the application and popularization of Patch-Clamp technique, the Automatic Patch-Clamp system is called into being. The usual data acquisition system with the PCI interface can’t satisfy our requests. So, we develop a new type of data acquisition and control interface based on the USB2.0 (Universal Serial Bus 2.0) and FPGA technology. The system is controlled by FPGA, output & input are synchronized, sampling frequency can be changed from 1kHz to 350kHz. It has 4 output control channels and 8 input acquisition channels. Digital isolators, reasonable power supply and reasonable grounding and potentiometer adjusting are used to achieve certain precision.This thesis begins with the system architecture of the data acquisition, and the choice of the key IC, more attention is focused on the design methods and on the technique details of the hardware. Then USB2.0 interface, complex logic control and signal regulating circuit, also the technologies in reducing noise of system are described in detail. In addition, some problems in circuit experiments are also discussed, test result, summary and prospect are mentioned at the conclusion of this thesis.更多还原