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Nowadays, digital circuits use both serial and parallel data transmission. It is important to ensure compatibility between them. The key component for that is the code converter, which can, without proper frequency specifications, be the “bottleneck” of the whole system. High data transmission density implies increasing of digital signal frequency. Thus, circuits for high frequency applications face high requirements. The siliconbased technologies often concede in terms of frequency capabilities. Using GaAs-based pHEMTs is one of the possible ways to overcome this. It might be useful for logic circuits in which data transfer speed and early decisions are crucial. In this paper, the serial-to-parallel code converter using GaAs pHEMT 0.5 μm technology is presented.

The article presents the results of the development and measurements of a specialized integrated circuit of an instrumentation amplifier (IA) with indirect negative current feedback. The schematic and the measurement results of the main characteristics for a silicon-on-insulator metal-oxide-semiconductor instrumentation amplifier are presented. The amplifier is intended for use as a part of a sensor network for monitoring the state of high-temperature objects. The temperature range of the instrumentation amplifier is up to 200 °C. Instrumentation amplifier has 11.8 MHz gain bandwidth product with a 3.3 V supply voltage. The measured gain is 27.50 dB and the error in setting the gain was 0.27 dB, the 3 dB bandwidth is 500 kHz.

Attenuators and phase shifters which are the circuits for amplitude-phase distribution control are key elements of antenna arrays. Dispersion of technology parameters results in deviation of the characteristics of integral circuits from rated values that requires application of the techniques for this effect compensation. In this paper there are considered the methods for development and calibration of the circuits in a basis of vector-sum signals allowing to modify both amplitude and phase of input high-frequency signal. It is proposed the method of calibration on a basis of interpolation of measured dependences of absolute value and phase of transfer factor on controlling voltage. Application of proposed method for calibration of vector phase shifter with operating frequency band 2.8–3.2 GHz fabricated with 0.18 mm CMOS allows to provide mean square deviation of phase error is not greater than 0.9°. At that amount of required measurements is 20 times decreased comparing known approach on a basis of measurement of all amplitude-phase states.