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Modern medical microwave diagnostic equipment requires the application of solutions related to the compactness of the developed devices and high performance. Ensuring these requirements is possible by using a modern semiconductor component base based on A3B5 compounds. One of the promising materials for this purpose is gallium nitride. The paper presents the design and manufacturing technology of one of the main control elements of the microwave signal in microwave radiothermometer - monolithic AlGaN/GaN/SiC HEMT SPDT transistor switch.

In the paper a new electrothermal average model of the diode–transistor switch operating in any dc–dc converter is proposed. With the use of this model the non-isothermal characteristics of dc–dc converters in the steady-state can be obtained. The method of formulation of such a model and its structure are described in detail. The correctness of the elaborated model was verified by comparing the SPICE simulated characteristics of the buck and boost converters operating both in the continuous and discontinuous conducting mode, obtained by the electrothermal dc analysis with the proposed model and by the electrothermal transient analysis with the physical models of the diode and the transistor.

This article reports on the variable temperature performance of a flexible printed transistor which works as a current driven switch. In this work, electronic ink is formulated from nanostructured silicon produced by milling polycrystalline silicon. The study of the silicon active layer shows that its conductivity is based on thermal activation of carriers, and could be used as active layers in active devices. We further report on the transistors switching operation and their electrical performance under variable temperature. The reliability of the transistors at constant current bias was also investigated. Analysis of the electrical transfer characteristics from 340 to 10 K showed that the printed devices’ current ON/OFF ratio increases as temperature decreases making it a better switch at lower temperatures. A constant current bias on a terminal for up to six hours shows extraordinary stability in electrical performance of the device.

The paper considers problems of increase of the energy efficiency in power high-voltage converters. Methods of efficient switching of the current in power switch circuits have been considered. Different design options of the power switch for power high-voltage applications are proposed. The reasons of the blocking capabilities disruption in dynamic switching processes in proposed switches topologies are revealed. The methods of switching capacity increase of considered switches are proposed.

The following article appeared in Applied Physics Letters 101,26 (2012): 261116 and may be found at http://scitation.aip.org/content/aip/journal/apl/101/26/10.1063/1.4773376, We present a time-resolved study of the logical operation of a polariton condensate transistor switch. Creating a polariton condensate (source) in a GaAs ridge-shaped microcavity with a non-resonant pulsed laser beam, the polariton propagation towards a collector, at the ridge edge, is controlled by a second weak pulse (gate), located between the source and the collector. The experimental results are interpreted in the light of simulations based on the generalized Gross-Pitaevskii equation, including incoherent pumping, decay, and energy relaxation within the condensate., The work was partially supported by the Spanish MEC MAT2011-22997, CAM (S-2009/ESP-1503), and FP7 ITN’s ‘‘Clermont4’’ (235114), “Spin-optronics” (237252), and INDEX (289968) projects.

A polariton condensate transistor switch is realized through optical excitation of a microcavity ridge with two beams. The ballistically ejected polaritons from a condensate formed at the source are gated using the 20 times weaker second beam to switch on and off the flux of polaritons. In the absence of the gate beam the small built-in detuning creates a potential landscape in which ejected polaritons are channelled toward the end of the ridge where they condense. The low-loss photonlike propagation combined with strong nonlinearities associated with their excitonic component makes polariton-based transistors particularly attractive for the implementation of all-optical integrated circuits. Published version

Besides identifying objects ultra high frequency radio frequency identification (UHF RFID) can be used to control actuators like a simple transistor. The big problem of such scenarios is the minimal available energy for the switching operation and leads to a massive influence of the reading distance on the actuation time. The presented measurements, calculations and simulations show that it is generally feasible to control a transistor using a UHF RFID tag. The measured actuation time ranges from 339 μs at 2.5 m up to 0.222 s at 10 m. Based on this technology applications like a zero watt standby module can be implemented.

This article has no abstract. Keywords: field-effect transistor switch (FET); majority carrier device

In the paper a new method of an electrothermal analysis of dc-dc converters operating in the steady-state is proposed. This method is based on the proposed by the authors electrothermal Ben-Yaakov model. This model was verified by comparison of SPICE simulated characteristics of the BUCK converter obtained by the proposed method and the electrothermal transient analysis.

Microcavity exciton polaritons are promising candidates to build a new generation of highly nonlinear and integrated optoelectronic devices. Such devices range from novel coherent light emitters to reconfigurable potential landscapes for electro-optical polariton-lattice based quantum simulators as well as building blocks of optical logic architectures. Especially for the latter, the strongly interacting nature of the light-matter hybrid particles has been used to facilitate fast and efficient switching of light by light, something which is very hard to achieve with weakly interacting photons. We demonstrate here that polariton transistor switches can be fully integrated in electro-optical schemes by implementing a one-dimensional polariton channel which is operated by an electrical gate rather than by a control laser beam. The operation of the device, which is the polariton equivalent to a field-effect transistor, relies on combining electro-optical potential landscape engineering with local exciton ionization to control the scattering dynamics underneath the gate. We furthermore demonstrate that our device has a region of negative differential resistance and features a completely new way to create bistable behavior., Comment: 15 Pages, 8 Figures

A small-size high-voltage (∼20 kV) microsecond pulse generator, which is based on a pulse transformer and loaded into a reactor with a pulse corona discharge, is described. Insulated-gate bipolar transistors (IGBTs) that form the switch are used in the low-voltage circuit of the generator. When the switch is open, voltage pulses with an amplitude of up to 1000 V are created across it and, hence, across the primary winding of the transformer. The pulse repetition rate of the generator is ∼20000 pulses/s.

This paper considers a scheme of a one-quadrant three-phase active rectifier (three-phase PFC), which consists of a bridge three-phase uncontrollable rectifier and boost dc converter. The converter provides a power factor of 0.955 with the possibility of improving and stabilizing the output voltage with minimal expenses for reactive elements and control circuits. The operation of the rectifier when powered by a nonsinusoidal and unbalanced network is considered.

В статье приводится принципиальная схема электронного управления порошковым электромагнитным тормозом (ПЭТ) с использованием транзисторного ключа. Описывается программно-аппаратная платформа системы управления и стратегия регулирования тормозного момента ПЭТ на основе ШИМ-сигнала с однопараметрической обратной связью по деформации динамометрической скобы. Приводятся результаты расчета требуемого тормозного момента по передачам, а также принципиальные схемы дифференциального и неинвертирующего усилителя сигнала с тензометрического моста.

Specifics of designing a pulsed arc welding power supply device are presented in the paper. Electronic components for managing large current was analyzed. Strengths and shortcomings of power supply circuits based on thyristor, bipolar transistor and MOSFET are outlined. As a base unit for pulsed arc welding was chosen MOSFET transistor, which is easy to manage. Measures to protect a transistor are given. As for the transistor control device is a microcontroller Arduino which has a low cost and adequate performance of the work. Bead transfer principle is to change the voltage on the arc in the formation of beads on the wire end. Microcontroller controls transistor when the arc voltage reaches the threshold voltage. Thus there is a separation and transfer of beads without splashing. Control strategies tested on a real device and presented. The error in the operation of the device is less than 25 us, it can be used controlling drop transfer at high frequencies (up to 1300 Hz).

Antenna switch module(ASM) for quad-band was developed. This module was integrated by RFIPD(RF integrated passive device) and transistor switch instead of LTCC-type device using low pass filters, diodes and passive elements in RF front end module for cellular phone. This module leads to low cost and miniaturization(The area is and the thickness is 0.8 mm). The insertion loss and the return loss of each band were averagely measured as 1.0 dB(insertion loss), 15.1 dB(GSM/EGSM return loss) and 19 dB(DCS/PCS return loss), respectively.