Design And Analysis Of Multi-channel Data Acquisition Circuit For CMUT

With the development of medical ultrasonic imaging technology,CMUT ultrasonic transducer based on MEMS technology has become an effective substitute for piezoelectric ultrasonic transducer because of its high electromechanical conversion efficiency,easy to match with human impedance,wide frequency band and so on.The emergence of CMUT ultrasonic transducer technology paves the way for the trend of ultrasonic system miniaturization.Through miniaturization,many benefits can be obtained,including improving system reliability,portability and reducing cost.However,the electrical signal output of CMUT ultrasonic transducer when receiving ultrasonic signal is relatively weak,so the signal detection and multichannel data acquisition circuit for CMUT ultrasonic transducer are designed in this paper.The device parameters of CMUT,the hardware design of the circuit and the application test of CMUT device are discussed in detail,which provides hardware support for the later application of CMUT ultrasonic transducer in medical ultrasonic imaging.Based on the analysis of the research status of medical ultrasonic imaging system and front-end circuit of CMUT ultrasonic transducer at home and abroad,the basic structure,working principle and equivalent circuit model of CMUT ultrasonic transducer are introduced,the voltage setting of CMUT ultrasonic transducer is analyzed theoretically,and the parameters of CMUT ultrasonic transducer are tested,such as C-V,impedance,transmission voltage response level,receiving sensitivity and so on.The purpose of this paper is to provide reference for the design and follow-up experiments of signal detection and data acquisition circuit of CMUT-oriented ultrasonic transducer.This paper focuses on the hardware circuit design of receiving echo signal for CMUT ultrasonic transducer.Combined with the working principle of CMUT ultrasonic transducer,the signal detection circuit of CMUT ultrasonic transducer and the multi-channel data acquisition circuit of ultrasonic echo signal are designed to realize the detection,reception,and acquisition of weak echo signal of CMUT ultrasonic transducer.By building a test platform,the performance of CMUT ultrasonic transducer signal detection circuit and multi-channel data acquisition circuit is tested,and then combined with CMUT ultrasonic transducer for reception,transmission,and reflection testing.The experimental results show that both the signal detection circuit and the data acquisition circuit can achieve the established function and the signal is good,the signal detection circuit can detect the weak echo signal of the CMUT ultrasonic transducer,and the data acquisition circuit can collect the echo signal and transmit it to the host computer.It shows that CMUT ultrasonic transducer has good transmission and reflection ability,and verifies the feasibility of the application of CMUT ultrasonic transducer signal detection circuit and multi-channel data acquisition circuit in ultrasonic imaging system.