MICROELECTRONIC DETERMINISTIC CHAOS OSCILLATOR BASED ON BIPOLAR TRANSISTOR STRUCTURE WITH NEGATIVE DIFFERENTIAL RESISTANCE

Abstract

The paper deals with a well-known electrical circuit of a relaxation oscillator based on a bipolar transistor structure with a negative differential resistance and a static S-type voltage-amperage characteristic. Such a generator is easy to manufacture and operates stably in the relaxation mode. By including additional passive elements in its electrical circuit, a stable chaotic mode of the generator is ensured. The chaotic mode of a relaxation oscillator based on a bipolar transistor structure with a negative differential resistance with a static S-type voltage-amperage characteristic is investigated. Two variants of the circuitry realization of a deterministic chaos generator based on a bipolar transistor structure with a negative differential resistance are considered. The self-oscillatory system of the deterministic chaos generator is of the fourth order (two degrees of freedom). Mathematical models describing dynamic processes in the electrical circuit of a deterministic chaos generator are presented. The numerical solution of the system of nonlinear differential equations is performed using the Runge-Kutta method. The electrical circuit of a deterministic chaos generator based on a bipolar transistor structure with a negative differential resistance was computer-modeled in the Multisim program. The results of computer modeling of a microelectronic deterministic chaos generator are presented. The modeling was carried out using PSPICE models. The time and frequency characteristics of the generated oscillations and phase portraits of the microelectronic deterministic chaos generator in the planes of the generated voltages are obtained. By controlling the voltage values of both power supplies of the microelectronic chaos generator circuit, it is possible to change the parameters of the generated chaotic voltages within a wide range during the stable operation of the generator. The paper presents the amplitude-frequency spectra of the generated chaotic electric oscillations. Using the obtained research results, a histogram of the distribution function of chaotic voltage values was constructed using MATLAB.