MODIFIED CFOA AND ITS APPLICATION FOR THE SIMULATION OF INDUCTOR, FILTER AND INVERSE FILTER

Abstract

The recent trend in electronics has been towards reducing the size of circuits, a trend which culminated in the development of integrated circuits, but it has been proven impractical to achieve a comparable reduction in the size of inductors because of the relation between the size of inductor and the quality factor. Also inductors are seldom used at low frequencies because at very low frequency the size and weight of inductors become exceedingly large and quality factor becomes very low. Fortunately, active circuits can sometimes synthesize the equivalent of an inductor with high quality factor. In this dissertation, we have presented a modified current feedback operational amplifier (MCFOA), which is more suitable for realizing simulated inductors and active filters. New grounded inductor and floating inductor have been simulated using a minimum number of passive components based on one or two modified current feedback operational amplifiers (MCFOAs) and the result is validated with the implementation of RL high pass filter. To show the flexibility of the proposed MCFOA, a single input three output (SITO) voltage mode filter and three input single output (TISO) voltage mode filters employing a single MCFOA have been simulated using the PSPICE program. In communication, control and instrumentation systems an electrical signal may get altered by many linear or nonlinear transformation caused by the signal processors or transmission system. To recover these distortions of the signal, a system is required that has inverse transfer characteristics of the original system. Inverse filter can correct these distortions because it has frequency response, which is the reciprocal of the frequency response of the system that caused the, distortion. In this dissertation, inverse filters have been designed using both the Modified current feedback operational amplifier (MCFOA) and standard AD844 CFOA. The workability of the proposed inverse filters is demonstrated by PSPICE simulations.