Omelchuk N. Measuring self-oscillator frequency converters for industrial microelectronsc sensors

Object - characteristics of self-oscillator frequency sensors, which are meant for technological equipment of the semiconductor industry; aim - investigation and development the measuring self-oscillator frequency converter (MFC) for integrated frequency sensors of the technological equipment; searching and theoretical basing for effective ways of circuit and technical characteristics improvement as for well-known MFC, so and novel one; experimental investigations of the new developed MFC; methods - of solid-state physics, circuit theory, automatic control system theory, regression analysis, mathematical statistics, design of experiments, computer simulation; novelty - it is shown, that a threshold of sensitivity for frequency sensor is determined by the fluctuation instability of the MFC self-oscillator, which depends in the main from noises of operational amplifier and negative feedback circuit; it is developed the novel scheme of MFC, which is based on RC-type self-oscillator with diode-capacitivephase-shifter in positive feedback circuit; multifactor model of the MFC non-linearity is proposed on the base of the scheme investigation; results - it is developed the mathematical models of various MFC schemes, which takes into account the fluctuation instability of output signal frequency (period); novel mathematical model and equivalent circuit for a sensitive element on the Shottky diode base, which can be adapted to operating conditions, are developed; area of application - technological equipment of the semiconductor industry that works in a production package with electromagnetic noises.