Increasing the sensitivity and radiation resistance of temperature sensor-converters using generators based on unijunction transistors

Abstract

The authors experimentally study the influence of temperature and radiation on the characteristics of generators based on a unijunction transistor (UJT). It is shown that when using a UJT-based generator as a sensor-converter with a frequency output, field-effect transistors are placed into the UJT emitter and base circuits to increase the dependence of frequency on temperature. Maximum sensitivity with direct dependence of frequency on temperature is achieved when a field-effect MOS transistor is connected to the emitter circuit UJT, and a field-effect transistor with a p-n junction is connected to the base circuit. The influence of radiation on the thermal sensitivity of generators is studied. The component transistors are irradiated with a flow of electrons, γ-quanta and neutrons. It is established that the irradiation of each transistor has a different effect on the initial frequency of the generator; it either decreases or increases. It is shown that it is possible to reduce the dependence of the output frequency on radiation using a transistor generator circuit with the opposite sign of the change in the generator frequency due to radiation. Maximum compensation for the effect of radiation on the output signal can be obtained by using a MOS transistor in the UJT emitter circuit, and a transistor with a p-n junction in the base circuit. The study establishes the limit values for fluxes of various radiations, after which the generator stops working.