面向电容式微机械超声换能器器件的32通道收发电路设计与测试  

Design and test of 32-channel transceiver circuit for capacitive micromachined ultrasonic transducer device

作　　者：陈谋 何常德[1] 孟亚楠 张斌珍[1] 任勇峰[1] 张文栋[1] CHEN Mou;HE Changde;MENG Yanan;ZHANG Binzhen;REN Yongfeng;ZHANG Wendong(Key Laboratory of Instrumentation Science&Measurement,Ministry of Education,North University of China,Taiyuan 030051,China)

机构地区：[1]中北大学仪器科学与动态测试教育部重点实验室,太原030051

出　　处：《应用声学》2022年第3期436-446,共11页Journal of Applied Acoustics

基　　金：国家重点研发计划项目(2016YFC0105000,2018YFF01010500);国家重大科研仪器研制项目(61927807);国家电网公司科技项目(SGSXSZOOFCWT2000147);山西省“1331工程”重点学科建设计划项目。

摘　　要：针对以电容式微机械超声换能器(CMUT)阵列为探头的超声成像系统,设计了一种兼具现场可编程门阵列(FPGA)控制、脉冲驱动以及微弱电流信号检测功能的电路。利用FPGA产生64路控制信号,控制脉冲信号的频率、脉冲个数、占空比等参数;脉冲电路在FPGA以及直流电压的控制下,产生32路脉冲信号;接收电路通过跨阻放大结构实现32路电流信号检测;32通道收发电路利用脉冲产生芯片内自带的T/R开关进行高压隔离。通过搭建测试平台,对收发电路功能及一致性进行测试,并连接CMUT进行自发自收测试。测试结果表明,32通道收发电路具有良好的一致性,电路可以实现基于CMUT阵列的32通道超声信号的发射,检测回波信号,并对CMUT器件的带宽进行测试。电路具有功能完善,结构稳定的优点,为基于CMUT阵列的超声成像系统的应用提供了硬件支持。Aiming at the ultrasonic imaging system with capacitive micromachined ultrasonic transducer(CMUT)array as probe,a circuit with field programmable gate array(FPGA)control,high-voltage drive and current signal detection function is designed.FPGA is used to generate 64 channel control signals to control the frequency,pulse number,duty cycle and other parameters of the pulse signal.The pulse circuit generates 32 channel pulse signals under the control of FPGA and DC voltage.The 32 channel transceiver circuit uses the T/R switch in the pulse generator chip for high-voltage isolation.The 32-channel current signals are detected by transimpedance amplifier(TIA).By building a test platform,the function and consistency of the transceiver circuit are tested,and the CMUT is connected to test its own transmitter and receiver.The test results show that the 32 channel transceiver circuit has good consistency.The circuit can transmit 32 channel ultrasonic signals based on CMUT array and detect the echo signal,and it can test the bandwidth of CMUT device.The circuit has the advantages of perfect function and stable structure,which provides hardware support for the application of ultrasonic imaging system based on CMUT array.

关 键 词：电容式微机械超声换能器 FPGA控制 脉冲驱动 电流信号检测 收发 

分 类 号：TN492[电子电信—微电子学与固体电子学]