Chaos from a family of minimum-component oscillators

A family of oscillators that employ the current feedback op amp as the active building block and that contain the minimum number of components is modified for chaos using a single discrete nonlinear element, namely a junction field effect transistor (JFET) operating in its triode region. The proposed family consists of three oscillator circuits, two of which remain to be of minimum components when modified for chaos while the third requires one more additional resistor to be added. The generated chaotic signal from all circuits persists for a wide and continuous range of parameter values and in different frequency bands. Design equations of the circuits as ordinary sinusoidal oscillators are shown to be useful as the start point for chaos modification. Experimental laboratory results and PSpice simulations confirm the chaotic behavior of the modified circuits. (C) 1997 Elsevier Science Ltd.