DESIGN OF FILTERS USING CURRENT FEEDBACK OPERATIONAL AMPLIFIER (CFOA) IC AD844

Abstract

Analog filters play a key role in any modern communication, instrumentation and electronic system. Though today the entire signal processing world seems to be digital, the presence of continuous time filters can be found at every interface with analog world. With the evolution of several new active building blocks in open literature, there is a great advancement in active filter deign. Current Feedback Operational Amplifier is an active building block which is characterized by a very high slew rate and can be used to replace the traditional, internally compensated voltage operational amplifier (741 type) in RC active filters. Since CFOA have gain-bandwidth independence and higher slew rate as compared to to traditional VOAs basic to higher order filter are designed using CFOA AD844. Active simulation of LC ladder is done by Operational simulation approach. The present work deals with the Realization of First order, Second order and higher order filters using CFOA. Also the gain-bandwidth independence has been proved by designing an inverting amplifier.