Various Order Low–Pass Filter with the Electronic Change of Its Approximation

Abstract

A design of a low pass frequency filter with the electronic change of the approximation characteristics of resulting responses is presented. The filter also offers the reconnection–less reconfiguration of the order (1st, 2nd, 3rd and 4th order functions are available). Furthermore, the filter offers the electronic control of the cut–off frequency of the output response. The feature of the electronic change of the approximation characteristics has been investigated for Butterworth, Bessel, Cauer, Chebyshev and Inverse Chebyshev approximations. The design is verified by PSpice simulations and experimental measurements. The results are also supported by the transient domain response (response to the square waveform), comparison of group delay, sensitivity analysis and implementation feasibility based on given approximation. The benefit of the proposed electronic change of the approximation characteristics feature (in general signal processing or for sensors in particular) has been presented and discussed for an exemplary scenario.A design of a low pass frequency filter with the electronic change of the approximation characteristics of resulting responses is presented. The filter also offers the reconnection–less reconfiguration of the order (1st, 2nd, 3rd and 4th order functions are available). Furthermore, the filter offers the electronic control of the cut–off frequency of the output response. The feature of the electronic change of the approximation characteristics has been investigated for Butterworth, Bessel, Cauer, Chebyshev and Inverse Chebyshev approximations. The design is verified by PSpice simulations and experimental measurements. The results are also supported by the transient domain response (response to the square waveform), comparison of group delay, sensitivity analysis and implementation feasibility based on given approximation. The benefit of the proposed electronic change of the approximation characteristics feature (in general signal processing or for sensors in particular) has been presented and discussed for an exemplary scenario.