Recursive switched-capacitor filters having approximately linear phase characteristics

This paper presents a novel class of switched-capacitor structures for the realization of approximately linear phase recursive sampled-data filters. The proposed networks have very low sensitivity with respect to capacitance ratio errors and are compensated for operational amplifier finite gain effects. Sensitivity analysis has been carried out on a computer verifying the excellent performance of the proposed scheme, and some simulation results are shown. Comparisons with previously proposed approaches, such as equalized designs of elliptic filters and tapped delay line based realizations are included, as well.