生物医学信号前置放大器的设计与仿真

生物医学信号的振幅微小，频率范围较低，容易受外界干扰而积累大量环境噪声。为了提高测量的精准度，设计了一款高性能的低噪声前置放大器来有效提取生物电信号。前置放大器采用的是基于仪表放大器级联可变增益放大器架构，该架构可以实现对信号的1 000倍放大，并能达到良好的性能指标。仿真结果表明，在1 V的工作电压下，该前置放大器有较低的等效输入参考噪声1.584 2 μV，较低的功耗2.92 μW，适用于生物医学信号采集方面的应用。

The Design and Simulation of Biomedical Signal Pre-amplifier

Biomedical signals are of small amplitude and low frequency so that it is easily disturbed by the external environment, leading to superimpose a lot of noise. For the sake of increasing the accuracy of measurements, a pre-amplifier with good performance in order to extract biological signals effectively is proposed. The pre-amplifier is cascaded by instrumentation amplifier and variable gain amplifier so that it can achieve a signal amplification of 1000 times, and can achieve good performance. The simulation results indicate that the pre-amplifier has low equivalent input reference noise of 1.584 2 μV and low consumption of 2.92 μW under the operation voltage of 1 V, it is applicable in the field of biomedical signal acquisition.