A fully integrated powerline filter for biopotential acquisition systems

4^th International Conference and Exhibition on Biosensors & Bioelectronics

September 28-30, 2015 Atlanta, USA

Hussain A Alzaher

KFUPM, Saudi Arabia

Posters-Accepted Abstracts: J Biosens Bioelectron

Abstract :

Low frequency filters has wide range of applications in biomedical signal processing. It is particularly desired for biopotential acquisition systems to eliminate powerline frequency disturbance from the measured signal using analog notch filters. Such interference concurrently occurs within the same band where biopotential and other physiological signals have most of their energy. Examples include ECG, electroencephalogram (EEG), and electromyogram (EMG) recordings. The work assesses the available solutions. Then, it presents a new notch filter design avoiding common drawbacks and providing improved characteristics. The proposed notch filter incorporates R-2R ladders allow the realization of large time constant in small area. The main features of the presented solution include (i) Integration into a single chip (i) Low power consumption in order to reduce amount of heat, decrease battery size and increase battery life, and (iii) High linearity to avoid generating harmonics that could be more dangerous than the powerline interferences. In fact, low noise requirement (to process the weak physiological signals) would be relieved in presence of pre-amplification and would converge to requirement (iii). Programmability is also incorporated to adjust the filter zero frequency compensating for inaccurate component values, process variations, and temperature changes. The proposed filter design is systematically identified to be the optimum. Main claims are supported with analytical proofs. Also, the operation and results are verified through IC fabrication and experimental results. Experimental results show significant improvement in terms of power consumption and linearity compared with the available solutions. Also, measurement validations using real biomedical signals are provided.

Biography :

Email: alzaherh@kfupm.edu.sa