Karnajit Burman,Bikash Chandra Bag,Anup Gorai,



Lowpass filter,Active Filter,Bio-medical application,Fourth order filter,


We have designed a fourth-order active lowpass filter which is a cascade version of two-second-order lowpass filters. To achieve the application, the Sallen-Key and conventional second-order filters are used in the first stage and second stages respectively. This filter is designed especially for biomedical applications for the detection of very low frequencies in the range from 1 Hz to 100 Hz.  We get stable output waveforms with high selectivity, fewer harmonics, and sharp waveform crest and trough.


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