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Open loop control system is the type without feedback, that is, no sensor sensing the control variable, hence works on time basis. The paper established the facts that the system will prevent ubiquitous fire incidences associated with electric stoves and other heating devices. It describes the application of simple electronics circuitries in designing the low cost Cooker Control Device. The building blocks of the unit were designed one after the other using preferred components available in the local markets. The project was wired on Breadboard. The board permits the design to be tested without employing soldering processes. The design enumerates some important construction precautions which are further accentuated with the inclusion of various tips on healthy soldering processes. It is believed that the unit will prevent fire incidences associated with electric cooker. Simple explanations given to drive home power electronics principles used and copious illustrations rendered will make the innovative and ingenuous enterprise interesting to power electronics enthusiasts and other professionals alike. The paper recommends incorporation of embedded system with Liquid Crystal Display in the future design improvement.

В дипломній роботі представлено огляд науково-технічної літератури по існуючим системам віддаленого моніторингу та керування промисловим обладнанням, зазначені переваги та недоліки вже існуючих систем. При ознайомленні з системою віддаленого моніторингу та керування промисловим обладнанням більш детально, можна зробити висновок, що найважливішими параметрами, з якими пов’язана робота системи віддаленого моніторингу та керування промисловим обладнанням, є швидкість передачі, режими роботи, підтримувані інтерфейси виведення даних, а також надійність та захищеність від перешкод. Необхідність точної роботи необхідна при керування системами виробництва. Розроблена конструкція пристрою, структурна та електрична принципова схеми системи віддаленого моніторингу та керування промисловим обладнанням. The thesis presents a review of scientific and technical literature on existing systems for remote monitoring and control of industrial equipment, the advantages and disadvantages of existing systems. When getting acquainted with the system of remote monitoring and control of industrial equipment in more detail, we can conclude that the most important parameters associated with the operation of the system of remote monitoring and control of industrial equipment are transmission speed, operating modes, supported output interfaces and reliability and protection from interference. The need for accurate work is necessary in the management of production systems. The design of the device, structural and electrical schematic diagrams of the system of remote monitoring and control of industrial equipment are developed.

In real inverters' operations, it is essential to insert delay time in the pulses provided to the inverter switches to protect the DC link against the short circuits. From this situation, the dead time phenomenon is introduced that causes undesirable performance and distortion of the output signal. Previously, researchers have proposed various schemes for compensating or eliminating dead-time. In this paper, a new dead-time elimination (DTE) scheme is proposed with a guarantee algorithm to eliminate dead-time and overcome the issues produced at the zero-currents-crossing point (ZCC). This method does not require additional hardware or filters to determine the polarity of the output current, and its principle is very simple to implement. The developed DTE method completely removes the dead-time issues on the magnitude and phase of the output voltage, and avoid the problems which can be induced around the ZCC. The results confirm the effectiveness and safety of this method.

U ovom radu cilj je dizajnirati sklop koji upravlja elektronskom bravom preko GSM/GPRS modula. SMS poruke će biti način komunikacije između korisnika i sustava. U radu je detaljno opisana hardverska i softverska implementacija sustava. Glavne komponente sustava su Arduino UNO, GSM Shield SIM800F te tranzistorska sklopka. Nakon što se prikaže način spajanja sklopa biti će objašnjen komunikacijski protokol GSM modula odnosno AT komande, i implementacija rješenja odnosno objašnjenje cijelog koda. Kao rezultat dobiva se jedan admin koji daje i oduzima pravo pristupa određenim brojevima mobitela., The goal of this project is to design electronic circuit which can manage electronic lock based on GSM/GPRS module. SMS messages will be comunication channel between users and system. In this project it is explained softwer and hardwear configuration of system in detail. The main components are : Arduino UNO, GSM Shield SIM800F and transistor switch. After shematic design, comunication protocol for GSM module (AT commands) and the code will be explained as well. As a result there is one admin who can allow or district access to variuos phone numbers.

Объектом исследования является ключевой генератор радиопередающего устройства (РПдУ) импульсно-фазовой радионавигационной системы (ИФРНС). Выполнено моделирование и исследование режимов работы ключевого генератора при частотной манипуляции. Разработана математическая модель сигнала, формируемого ключевым генератором в эквиваленте передающей антенны (последовательном колебательном контуре) при подаче на него последовательности Ð·Ð½Ð°ÐºÐ¾Ð¿ÐµÑ€ÐµÐ¼ÐµÐ½Ð½Ñ‹Ñ Ð¿Ñ€ÑÐ¼Ð¾ÑƒÐ³Ð¾Ð»ÑŒÐ½Ñ‹Ñ Ð¸Ð¼Ð¿ÑƒÐ»ÑŒÑÐ¾Ð² напряжения с переменной длительностью. Выполнено исследование Ð¿ÐµÑ€ÐµÑ Ð¾Ð´Ð½Ñ‹Ñ Ð¿Ñ€Ð¾Ñ†ÐµÑÑÐ¾Ð², Ð²Ð¾Ð·Ð½Ð¸ÐºÐ°ÑŽÑ‰Ð¸Ñ Ð¿Ñ€Ð¸ изменении длительности Ð³ÐµÐ½ÐµÑ€Ð¸Ñ€ÑƒÐµÐ¼Ñ‹Ñ ÐºÐ»ÑŽÑ‡ÐµÐ²Ñ‹Ð¼ генератором Ð¿Ñ€ÑÐ¼Ð¾ÑƒÐ³Ð¾Ð»ÑŒÐ½Ñ‹Ñ Ð¸Ð¼Ð¿ÑƒÐ»ÑŒÑÐ¾Ð² напряжения. Исследование проведено на математической модели, реализованной в среде математического моделирования Matlab, а также на имитационной модели, реализованной в среде ÑÑ ÐµÐ¼Ð¾Ñ‚ÐµÑ Ð½Ð¸Ñ‡ÐµÑÐºÐ¾Ð³Ð¾ моделирования MicroCap. Выполнен сравнительный анализ результатов, Ð¿Ð¾Ð»ÑƒÑ‡ÐµÐ½Ð½Ñ‹Ñ Ð´Ð°Ð½Ð½Ñ‹Ð¼Ð¸ методами. Проведена разработка ключевого генератора: разработка ÑÑ ÐµÐ¼Ñ‹ электрической принципиальной, выбор элементной базы, расчет Ð¾ÑÐ½Ð¾Ð²Ð½Ñ‹Ñ ÑÐ»ÐµÐºÑ‚Ñ€Ð¸Ñ‡ÐµÑÐºÐ¸Ñ Ð¿Ð°Ñ€Ð°Ð¼ÐµÑ‚Ñ€Ð¾Ð² в режиме частотной манипуляции., The object of the research is the switching generator of the radio transmitter of the pulse-phase radio navigation system (PPRNS). The modeling and research of the operating modes of the switching generator during frequency shift keying have been carried out. The mathematical model of the signal generated by the switching generator in the equivalent of the transmitting antenna (sequential oscillatory circuit) is developed when a sequence of alternating rectangular voltage pulses with variable duration is fed to it. The research of transient processes arising when the duration of the rectangular voltage pulses generated by the switching generator is changed. The research was carried out on a mathematical model implemented in the Matlab mathematical modeling environment, as well as on a simulation model implemented in the MicroCap circuit modeling environment. A comparative analysis of the results obtained by these methods is carried out. The development of a switching generator was carried out: the development of an electrical schematic diagram, the choice of the element base, the calculation of the main electrical parameters in the frequency shift keying mode.

This article presents a generalized method for calculating of switching processes in high-frequency switched-mode power supply converters.

Features of zero current and zero voltage switching quasi-resonant pulse converters control are analyzed in this paper. Ways to reduce dynamic losses in transistor switches are described. Reasons for changing parameters of currents and voltages in resonant circuits of these converters, as a result of which their resonance frequency changes, and consequences of this fact are justified. Principles of transistor switch automatic quasi-control are considered, whereby simplifies to synthesize of control systems and reduces dynamic losses in it.

A 5-bit digital controlled switch-type passive phase shifter realised in a 40 nm digital CMOS technology without ultra-thick metals for the 60 GHz Industrial, Scientific and Medical (ISM) band is presented. A patterned shielding with electromagnetic bandgap structure and a stacked metals method to increase the on-chip inductor quality factor are proposed. To reduce the insertion loss from the transistors, the transistor switches are implemented with a body-source connection. For all 32 states, the minimum phase error is 1.5°, and the maximum phase error is 6.8°. The measured insertion loss is -20.9 ± 1 dB including pad loss at 60 GHz and the return loss is >10 dB over 57-64 GHz. The total chip size is 0.24 mm2 with 0 mW DC power consumption.

The stacked polyphase bridges converter consists of several submodules that, on the input dc side, all are connected in series. Whereas controller designs presented in previous studies have been found promising for realizing equal voltage sharing between submodules, the survival and stability under fault conditions have not been studied. This paper presents a control strategy that enables survival of the converter after the occurrence of a sudden short circuit of a single transistor switch. The results are verified by simulations. QC 20161027

В даній статті розглянуті питання поліпшення енергетичних показників підвищуючого квазірезонансного імпульсного перетворювача з паралельним резонансним контуром, який перемикається при нульовому струмі (КРІП-ПНС) та розширення діапазону регулювання його вихідної напруги. Діапазон регулювання вихідної напруги запропоновано розширити за рахунок придушення паразитних коливань шляхом підключення додаткового діода. Крім того, в статті приведена порівняльна оцінка енергетичних втрат у транзисторних ключах паралельного КРІП-ПНС та імпульсного перетворювача (ІП) з широтно-імпульсною модуляцією (ШІМ) у широкому діапазоні робочих частот. This article describes the issues of energy indicators improvement for the boost quasi-resonant pulse converter with a parallel resonant circuit that switches at zero current (QRPC-ZCS) and the extension of its output voltage control range. It is proposed to extend the output voltage control range of the converter by suppressing the parasitic oscillation using connection of additional diode. Moreover, the article provides a comparative assessment of the energy losses in transistor switches of the parallel QRPC-ZCS and pulse converter (PC) with pulse-width modulation (PWM) in a wide range of operating frequencies. В данной статье рассмотрены вопросы улучшения энергетических показателей повышающего квазирезонансного импульсного преобразователя с параллельным резонансным контуром, переключающегося при нулевом токе (КРИП-ПНТ) и расширение диапазона регулирования его выходного напряжения. Диапазон регулирования выходного напряжения предложено расширить за счет подавления паразитных колебаний путем подключения дополнительного диода. Кроме того, в статье приведена сравнительная оценка энергетических потерь в транзисторных ключах параллельного КРИП-ПНТ и импульсного преобразователя (ИП) с широтно-импульсной модуляцией (ШИМ) в широком диапазоне рабочих частот.

A 5-bit digital controlled switch-type passive phase shifter realised in a 40 nm digital CMOS technology without ultra-thick metals for the 60 GHz Industrial, Scientific and Medical (ISM) band is presented. A patterned shielding with electromagnetic bandgap structure and a stacked metals method to increase the on-chip inductor quality factor are proposed. To reduce the insertion loss from the transistors, the transistor switches are implemented with a body-source connection. For all 32 states, the minimum phase error is 1.5°, and the maximum phase error is 6.8°. The measured insertion loss is -20.9 ± 1 dB including pad loss at 60 GHz and the return loss is >10 dB over 57-64 GHz. The total chip size is 0.24 mm2 with 0 mW DC power consumption.

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.

В статье рассмотрены некоторые особенности возникающие при работе высоковольтных импульсных трансформаторов на реакторы с коронным и барьерным разрядом представляющие собой емкостно-омическую нагрузку. The paper considers some of the features resulting from the operation of high voltage pulse transformers for reactors with corona and the barrier discharge is a capacitive-resistive load.

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

Power field effect transistors are used and will be used in almost all automotive systems. Control of field effect power transistors requires isolated 5V control signals and isolated 12V DC sources. The first problem is resolved by using optical pairs: light emitting diodes with phototransistors. The second problem can be resolved by using impulse voltage sources. The primary coil of a transformer is connected to the battery by a transistor switch. In the first period of operation of this voltage source, the energy is stored in the magnetic field of transformer's inductance. In the second period, the energy is delivered to the output voltage source. Energy is delivered from the secondary transformer's coil to the output capacitor through a diode. As a rule, one separate voltage source has a small power, that is why one impulse voltage source can have the necessary number of isolated output voltage sources, i.e., 3, 6, 9, 12, etc So, we can design an impulse DC to DC voltage source with multiple isolated output voltage sources. By changing the charge time of the inductor, we can control the output voltage by using negative feedback proportional to the output voltage and/or current. In the report, different variants of impulse voltage sources are considered, with analog base elements and on the base of microprocessors. Analyses operation of these impulse voltage sources gives us an opportunity to determine the period (frequency) of internal operation with ordered maximum transformer efficiency values. The concept of controlled impulse voltage sources is very important because these sources are very simple. They are reliable and have high level of electrical isolation. Copyright © 2009 SAE International.

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.

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

High-accuracy digital MMIC RF attenuator for cellular phones is presented. Designing high accuracy digital MMIC RF attenuators is challenging due to the non-ideal characteristics of the transistor switches used in the attenuator and other parasitic effects. This problem can be circumvented by simultaneous optimization of the attenuator circuit at every possible input bit configuration. Without this optimization scheme, it would be extremely difficult to compensate the non-ideal transistor switch characteristics to achieve high accuracy. A design methodology is presented.

Experimental study of sealed-off CuBr laser was performed with the aim to prolong its lifetime. Electrical circuit with a transistor switch was used. Optimal pulse repetition rate corresponding to maximum output radiation power was obtained.

This paper presents the design of a 1K-byte random access memory using a cross-coupled complementary transistor switch (CTS) cell. The memory operates with a 4.25-V power supply and achieves a 15-ns access time with a power dissipation of 1.8 W. This paper also demonstrates the advantages of using the CTS cell to achieve high circuit density and good performance of memory arrays. Array attributes, cell selection criteria, and cell operation (both ideal and in situ) as well as design considerations are covered. Hardware performance is also briefly summarized.

In an epitaxial transistor operating in saturation, charge is stored not only in the active and passive base regions but also in the region bounded between the collector junction and n - n + interface. The saturation operation of a transistor switch is characterized by a single most fundamental parameter, the saturation time constant, which may be related to the intrinsic physical structure of the transistor. In this paper, an attempt has been made to correlate the saturation behaviour of an epitaxial planar transistor with its physical structure. The analysis takes into account the effects of n - n + interface in the collector and the retarding-accelerating built in field for the minority carriers in the base, both of which so far have been subject to gross simplifications. The theoretical conclusions have been verified experimentally for some typical epitaxial planar transistors.

Trains of sine waves of varying duration and frequency are sometimes required in auditory research or in experiments where nerve or muscle preparations are stimulated. One of the problems involved in such work is the need for a stimulus which is symmetrical to ground (pedestal-free) and which has a small rise time, so that the intensity-latency relationship can be correctly evaluated. It is sometimes also important to know the phase angle at which the sine wave has begun. A switch is described which was designed to meet these conditions. It uses a "normal" transistor in which the functions of the emitter and collector are interchanged periodically by a sinewave oscillator. The paper analyzes the behavior of a "normal" transistor as a bidirectional switch and describes how a suitable circuit can be designed.

The purpose of this paper is to calculate the voltage drop across a closed transistor switch in the presence of intermediate-level operating conditions. The problem is formulated to include the important one-dimensional effects associated with intermediate-level operation in such a way that the low-level theory is included as a special case. Experimental verification of the theory has been obtained over a moderately wide range of base drives.

The instrument described provides rectangular pulses separated from ground by less than 20 pf capacity and essentially infinite resistance. The transistor switch provides pulses at low output impedance, from a floating battery, of 0 to 80 v in amplitude and variable in duration by the width of a triggering stimulus from a conventional stimulator or pulse generator. The device is of particular use in biological experiments where isolation of a stimulating pulse from ground is required.

A flexible inexpensive programming device for use with a magnetic tape deck is described. The programmer provides independent control for up to 15 different experimental events. It can be constructed from digital ICs for less than $50 and may be used with an inexpensive tape deck. A general-purpose transistor switch is also described.