脑电图机放大电路的设计与仿真  

Design and Simulation of Amplifier of Electroencephalograph

作　　者：刘国立[1] 王一丁[1] 

机构地区：[1]中国科学院研究生院,北京100049

出　　处：《计算机仿真》2008年第8期300-303,共4页Computer Simulation

摘　　要：在现有生物电放大器研究的基础上,改进并设计了一种符合脑电信号特征的新型高性能放大电路,避免了传统生物电放大电路冗繁的模拟滤波环节。设计中利用TI公司的低功耗仪表放大器INA326,得到了较高的共模抑制比;进而通过50Hz陷波器和低通滤波器,有效地消除了脑电信号强大背景噪声的干扰,实现了微弱脑电信号的放大和采集;最后利用TI-NA仿真软件对该前置放大电路和50Hz陷波器进行了设计的仿真验证。结果表明,放大电路具有高输入阻抗、高共模抑制比、低噪声、非线性度小、抗干扰能力强的特点,具有较强的实用性。On the basis of existing biological electricity amplifier which is studied, a design of new type and high performance amplifier circuit was proposed which is in agreement with the characteristic of the EEG signal and the circuit has prevented the traditional design from enlarging the miscellaneous simulation of the circuit and straining the wave link. First, the high Common Mode Rejection Ratio （CMRR） was achieved by the use of instrumentation ampfifier INA326 with low consumed power; Then, in order to eliminate the strong background noises of EEG signal, 50Hz notch filter and low -pass filter have been introduced in this design and realized the amplification and collection of weak EEG signal. Finally, the feasibility of the design is proved according to the simulation of preamplifier and 50Hz notch filter by the use of TINA software. The results indicate that the circuit has a bright applicable future because of its characteristics of high input impedance, high CMRR, low noises, low degree of nonlinear and high anti - interference ability.

关 键 词：脑电 仿真 共模抑制比 前置放大器 陷波器 

分 类 号：TP391.9[自动化与计算机技术—计算机应用技术]