MEMS心音传感器及检测电路优化设计  

Optimization Design of MEMS Heart Sound Sensor and Detection Circuit

作　　者：刘佳琦 张国军[1] 崔建功[1] 史鹏程 Liu Jiaqi;Zhang Guojun;Cui Jiangong;Shi Pengcheng(State Key Laboratory of Dynamic Measurement Technology,North University of China,Taiyuan 030051,China)

机构地区：[1]中北大学省部共建动态测试技术国家重点实验室,太原030051

出　　处：《微纳电子技术》2024年第5期102-111,共10页Micronanoelectronic Technology

基　　金：国家自然科学基金面上项目(62274149,52175553);山西省基础研究计划资助项目(202103021224203,20210302123027);山西省“1331工程”重点学科建设计划资助项目。

摘　　要：对基于微电子机械系统(MEMS)技术的心音传感器声敏结构进行了优化且设计了其检测电路。首先,针对心音信号的特点,设计了二次集成的扁平状仿生纤毛结构,对该结构进行仿真,确定了纤毛的尺寸参数和梁上最大应力1.2×10^(5) N/m^(2),对纤毛进行特征频率仿真,在硅油域中结果为711 Hz;其次由扁平状纤毛结构X轴接收噪声时梁上的应力仿真结果可知该结构具有抗干扰能力;最后设计了后端的放大电路和滤波电路并对传感器封装后进行测试。测试结果表明,该结构的信噪比达到了27 dB,较传统的圆柱形纤毛提高了35%,且其抗干扰能力也优于传统的圆柱形纤毛。优化过后的MEMS心音传感器具有抗干扰、低噪声、低成本、采集的信号不失真等优势,可为临床心音信号的采集提供关键核心部件。The sound-sensitive structure of heart sound sensor based on micro-electromechanical system(MEMS)technology was optimized,and its detection circuit was designed.Firstly,according to the characteristics of heart sound signal,a secondary integrated flat bionic cilia structure was designed.The dimensions of the cilia and the maximum stress of 1.2×10^(5) N/m^(2) on the beam are determined by simulation of the structure.The characteristic frequency simulation of the cilia shows the result of 711 Hz in the silicone oil field.Secondly,when the X axis of the flat ciliated structure receives noise,the stress simulation results on the beam show that the structure has anti-interference ability.Finally,the amplifying circuit and filtering circuit at the back-end was designed and the sensor was packaged and tested.The test results show that the signal-to-noise ratio of the structure reaches 27 dB,which is 35%higher than that of the traditional cylindrical cilia,and its anti-interference ability is better than that of the traditional cylindrical cilia.The optimized MEMS heart sound sensor has the advantages of antiinterference,low noise,low cost and no distortion of the collected signal,and it can provide key components for clinical heart sound signal acquisition.

关 键 词：微电子机械系统(MEMS)技术 心音传感器 处理电路 心音信号 信噪比 

分 类 号：TH776[机械工程—仪器科学与技术]