A Review on Different Filter Design Techniques and Topologies for Bio-potential Signal Acquisition Systems

There are few bio-potentials signals which is used for human-machine interface (HMI). Most extensively used bio-potential signal for HMI are electroencephalogram (EEG) and electromyogram (EMG). Measuring these bio-potential signals are of great challenge because these signals are of very low amplitude, which is easily corrupted by noise. This paper reviews different filter types, design topologies used in bio-potential signal acquisition systems. These bio-potentials signals are mostly low frequency signals, so the filters designed are in the low frequency range below 1 kHz. Many have proposed data acquisition systems where the signal detection filter is either in analog domain or digital domain. The proposed Comb filter is based on operational transconductance amplifier and capacitor (OTA-C) topology, here low transconductance and low noise OTA in 45nm technology is used. The filter will be designed and simulated using Tanner tools. The proposed filter will reject signals at 50 Hz, 150 Hz and 250 Hz, and will pass rest of the spectrum.