电阻抗成像系统中采样信号电路的设计与实验验证OACSTPCD

This study delves into a key technology of electrical impedance tomography(EIT)-the implementation of signal sampling electronic circuit.The basic principles and technical requirements of the circuit are elaborated in detail,and advanced circuit design concepts and techniques are adopted to design a set of hardware circuits for lung ventilation visualization electrical impedance imaging equipment based on a high-performance FPGA dual-drive system,which mainly includes a sampling control unit,a voltage-controlled constant-current source module,a time-multiplexing module,differential amplification circuits and a safe voltage-tolerant isolation module unit.The method of signal acquisition using the control unit and time division multiplexing module is also discussed.And the experimental tests verify that the designed EIT hardware circuit is of high precision and good stability in signal acquisition process,and can meet the needs of clinical lung ventilation imaging.