A 5.5 μW 42 nV/√Hz Chopper stabilized Amplifier for Biomedical Application with Input Impedance Enhancement

Abstract

The continuous real-time monitoring of diverse physical parameters using biosignals like ECG and EEG requires the biomedical sensors. Such sensor consists of analog frontend unit for which low noise and low power Operational transconductance amplifier (OTA) is essential. In this paper, the novel chopper-stabilized bio-potential amplifier is proposed. The chopper stabilization technique is used to reduce the offset and flicker noise. Further, the OTA is likewise comprised of a method to enhance the input impedance without consuming more power. Also, the ripple reduction technique is used at the output branch of the OTA. The designed amplifier consumes 5.5 μW power with the mid-band gain of 40dB. The pass-band for the designed amplifier is 0.1Hz to 1KHz. The input impedance is likewise boosted with the proposed method. The noise is 42 nV/√H z with CMRR of 82 dB. All simulations are carried out in 180nm parameters.

Keywords

• biopotential amplifier
• input impedance
• noise
• power
• ecg
• eeg