心电信号调理电路设计

摘要

心电（Electrocardiograph）作为人体重要的生理及病理指标之一。具有重要的医学研究价值。针对其信号微弱、频率低、阻抗高、随机性强及易受干扰的特点，首先提出了信号调理电路设计的要求；然后针对性地选择元器件并设计硬件电路，其中包括：一级放大电路、调零电路、50Hz限渡电路、带通滤波电路及二级放大电路；最后对所设计的硬件电路进行实际测试。结果表明该调理电路具有输出波形稳定、噪声小和共模抑制比高的特点，提高了心电信号采集的精度。%ECG （Electrocardiograph） is one of the most important index of the human physiology and pathology, and provided with important medical researchful value . Basede on the characteristic of weak , low frcqueney, high impedance , strong randomicity and easily can be disturbed of EGG. The request of conditioning circuit for ECG is proposed, and the necessary compinents arc elected in accordance with the characters of pulse, and the circuit is design. There arc the circuit of the first amplification, the circuit of zero, the circuit of restricting the signals 50 Hz, the circuit of band-pass filter and the circuit of secondary amplification. The circuit of hardware designed has been tested, and the measurement shows that the conditioning circuit of pulse signals possesses the advantages of high CMMR （common model restrain ration）, low noise, the output is stabilization, and has enhanced the precision of collection for ECG.