Design of low-noise low-power ECG amplifier circuit with high integration level

Abstract

Electrocardiogram (ECG) is a common tool in medicine and is an important indicator for diagnosing many diseases. Nowadays, aspects such as low noise, low power, and high integration have become important indicators for ECG circuit design. Also, due to the low amplitude of ECG signals, ECG circuits need to have high gain to ensure accurate signal detection and analysis. Second, ECG signals are usually subject to interference from other parts of the body, so a high common mode rejection ratio (CMRR) is required to suppress these interfering signals. In this paper, we propose an ECG circuit composed of an amplifier with a drive right leg circuit (DRL) using pseudo-resistors as well as capacitors to improve the common instrumentation amplifier. The simulation using industrial-grade simulation software LTspice shows that the circuit has a voltage of 1.8 V, a bandwidth of 17 mHz-1 KHz, a gain of 55 dB, and an INR of 3.4 μVrms, and because the signal amplifier part of this circuit design consists of only pseudo-pseudo-resistors, capacitors, and mos tubes. Therefore, it has a smaller size and a higher degree of integration. In addition, the circuit has less power loss for the same amplification design. Overall, this design has excellent characteristics such as low noise, low power, and small size.