Analysis and Implement of ECG Front-End Signal Processing Circuit

In order to reduce the noise disturbance to ECG signals, ECG front-end signal processing method is proposed in this paper. In this method, the RFI filter is a bridge type differential low-pass filter. The input amplifier is high precision instrument amplifier AD8220 which has JFET input stage characteristic, the low-pass filter is a five order Bessel filter which has the most flat amplitude and phase response, and the right leg driving circuit is precision operational amplifier OP2177 which has low input bias current. The method is characterized with simpleness, easy integration, good stability and high precision. It is significant for the future electrocardiogram instrument.