Generalized second‐order active R filters

A generalized treatment of second‐order active R filters is presented. A general circuit configuration is derived whose transfer functions are expressed in terms of defined resistive transfer functions and the gains of two operational amplifiers. The general network uses fewer resistances than reported configurations and can be used to realize all second order functions including oscillators. This approach facilitates simple and systematic analysis of second‐order active R networks and leads to configurations having minimum component count.