A design and optimization of CMOS ECG amplifier applied to medical monitoring system

Abstract

ECG amplifier is widely used in medical monitoring system as a part of the transceiver circuit and sensors. For those who suffer from cardiovascular diseases, an ECG signal can reflect their heart conditions. This paper makes a research mainly on the design purpose of the ECG amplifier which includes low power consumption and high CMRR, and then presents the active load differential amplifier design to restrain the noise and to implement the function of amplify.  The design also displays how to maintain a balance between high DC gain and less distortion by setting the parameters. As is displayed in the figures, the ECG amplifier successfully removes the common-mode noise and achieves the ideal wave shape with the use of a software built-in calculator. The DC gain is about 60.55dB. When increases the DC gain with a fixed power consumption to 40dB, the wave shape will be a bit distorted. The design explains the application of the ECG amplifier into medical monitoring system in section 2 and proposes an example of ECG amplifier which can amplify and filter the original signal in section 3. Background knowledge, working process and measured results are given in this paper.