CHAOS FROM 2 MODIFIED OSCILLATOR CONFIGURATIONS USING A CURRENT-FEEDBACK OP AMP

Two oscillator configurations that employ the current feedback op amp (CFOA) as the active element are modified for chaos using a single dis crete nonlinear element, namely a junction field effect transistor (JF ET) operating in its triode region. The first oscillator is based on a passive Twin-T structure while the second oscillator is a Wien type o scillator. The generated chaotic signal from both circuits persists fo r a wide and continuous range of parameter values and in different fre quency bands that are easily adjusted by simple parameter scaling. The design equations of both configurations as ordinary sinusoidal oscill ators are also shown to be useful when modified for chaos. Experimenta l laboratory results and PSpice simulations are provided. (C) 1997 Els evier Science Ltd.