CIRCUIT FEATURES OF HIGH-TEMPERATURE ANALOG MICROCIRCUITS ON GAN AND GAAS TRANSISTORS

Abstract

High-temperature integrated circuits, which remain operational at temperatures above 150°C, are
required in many areas of industry: aerospace, aviation and automotive instrumentation, the petrochemical
industry, electric power, and military electronics. Currently, foreign enterprises are mass-producing
several high-temperature analog and analog-to-digital microcircuits based on silicon CMOS SOI structures
– ADS1278-HT, ADS1282-HT, ADS8320-HT, INA129-HT, INA333-HT, OPA2333-HT, etc. Hightemperature
silicon operational amplifiers and ADCs have also been developed in the Russian Federation.
However, the maximum operating temperature of such products does not exceed 200°C due to the limitations
of silicon technologies. For this reason, wide-bandgap semiconductors such as silicon carbide (SiC),
gallium nitride (GaN) and gallium arsenide (GaAs) are most often considered as semiconductors intended
for high-temperature microcircuits, which provide a number of characteristics necessary for hightemperature
applications: wide bandgap, high carrier saturation velocity and low concentration of intrinsic
charge carriers. An overview of the problems of developing high-temperature analog microcircuits
based on GaN and GaAs transistors is presented. The features of the current-voltage characteristics of
GaN and GaAs field-effect transistors operating in depletion and enhancement modes, electrical circuits
of typical analog devices (charge-sensitive and operational amplifiers, comparators, current followers)
and logical gates are considered. It is concluded that it is advisable to carry out the circuit synthesis of
GaAs analog microcircuits using field-effect transistors with an n-type channel operating in depletion
mode and p-n-p heterostructure bipolar transistors. Examples of such schemes are given. The relevance of
the above research is related to the problems of import substitution of microcircuits based on widebandgap
semiconductors (GaN, GaAs), providing a wide range of operating temperatures (over +150°C).