Active RC synthesis of a narrow band transfer function using Yanagisawa scheme

Abstract

Synthesis of active RC networks has become very important with the advent of integrated circuits. But for all such networks the stability and sensitivity consideration are very important. Particularly in the case of a narrow band filter design, the stability consideration becomes crucial because of the proximity of the poles to the imaginary axis. Here it haa been shown that for a second order narrow band transfer function using Yanagisawa scheme for synthesis, stability can be maximized by choosing the arbitrary poles of the RC network in a particular manner. For this particular choice of the poles the root sensitivities with respect to each element of the synthesized network have been considered. From these sensitivity considerations, the variable elements have been chosen for the control of the location of poles. This basic second order module has been used for the realization of higher order transfer functions. The technique has been illustrated by designing an eighth order narrow band transfer function useful for the intermediate frequency stage of broadcast receivers.