一种传声器极化电压测量装置的设计  

Design of a microphone polarization voltage measuring device

作　　者：李耀祖 张欢欢 王双杰 郭凯龙 LI Yaozu;ZHANG Huanhuan;WANG Shuangjie;GUO Kailong(Hangzhou Aisiwei Instruments Co.,Ltd.,Hangzhou 311122,China;Hangzhou Aihua Instruments Co.,Ltd.,Hangzhou 311122,China)

机构地区：[1]杭州爱思维仪器有限公司,浙江杭州311122 [2]杭州爱华仪器有限公司,浙江杭州311122

出　　处：《电子设计工程》2023年第24期177-180,185,共5页Electronic Design Engineering

摘　　要：针对目前电容式传声器极化电压测量过程中的操作繁琐、设备成本高等问题,设计了一种专用测量装置。采用普通的运算放大器组成电压跟随电路对输入信号做阻抗变换;采用隔离电源模块为电压跟随电路提供正负电源,并在其0 V输出端接入高压直流电源模块,提高阻抗变换电路的共模工作电压。通过样机的制作与测试,验证了设计和加工工艺的有效性。在测试信号为200 V时,测试结果的误差小于0.1%,满足相关计量规范的要求。装置能够有效降低测量过程的操作难度和设备复杂度,降低设备成本,可应用于声学测量放大器、声级计等精密声学测量仪器的极化电压测量。A special measuring device is designed to solve the problems of cumbersome operation and high cost in polarization voltage measurement of capacitive microphone.The input signal is impedance transformed by a voltage⁃following circuit composed of ordinary operational amplifier.The isolated power module is used to provide positive and negative power supply for the voltage following circuit,and a high voltage DC power module is connected to its 0 V output to increase the common mode operating voltage of the impedance conversion circuit.The validity of the design and processing technology is verified by making and testing the prototype.When the test signal is 200 V,the error of the test result is less than 0.1%,which meets the requirements of relevant measurement specifications.The device can effectively reduce the difficulty and complexity of the measurement process,reduce the cost of the device,and can be applied to the polarization voltage measurement of precision acoustic measurement instruments such as acoustic measurement amplifier and sound level meter.

关 键 词：传声器 极化电压 输出阻抗 声压灵敏度 

分 类 号：TN912[电子电信—通信与信息系统]