Low-sensitivity direct-form IIR SC filters with improved phase linearity

Abstract

This paper presents a novel approach for the design of infinite impulse response (IIR) switched-capacitor (SC) filters, based on the optimum allocation of poles and zeros of a transfer function. This approach is aimed at the reduction of sensitivity in the passband and improved phase linearity. Comparisons with classical filter designs are made. An illustrative design example of a proposed low-pass IIR SC filter structure is presented along with experimental results obtained from a prototype filter built and tested in the laboratory.