Realisation of High Input Impedance Universal Filter Using Current-Feedback Amplifiers

Anew scheme for the realisation of universal filter is presented. The proposed circuit is a high input impedance filter which employs as many as three current-feedback amplifiers and seven passive elements out of which six elements are grounded. The only floating element is a resistor. The proposed filter circuit realises lowpass, bandpass and highpass filter functions simultaneously for a single analog input voltage source. Also by using a summer at the output a band reject filter can be obtained. The orthogonal adjustment of omega(o) and filter-Q is possible. The component spread is very small. The sensitivity figures are under tolerable limits. The simulation results are included.