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Precise temperature control is crucial for the development of sensitive instruments, as temperature fluctuations will introduce many negative effects. In temperature control systems, $1/{f}$ noise is dominant in the low-frequency range, which limits the temperature control precision. To suppress the $1/{f}$ noise, AC bridges based on the modulation-demodulation method are commonly used. While the $1/{f}$ noise is suppressed, other types of noise rise to domination, further limiting the precision of the temperature control system. The response of the AC-bridge readout circuit to temperature fluctuation is the most serious. This paper proposes a method for suppressing the response of the AC-bridge readout circuit to temperature fluctuations. Using this method, the temperature coefficient of the readout circuit is reduced by matching the temperature coefficients of the used electro-components according to their weights of impact. This method has been verified in the test of a precise temperature control system designed for a superconducting gravimeter. The temperature coefficient of the AC-bridge circuit was reduced by approximately 57.4 times compared with the unmatched AC-bridge circuit, and the temperature fluctuation in the vacuum chamber of the superconducting gravimeter was controlled within $\pm 5~\mu \text{K}$ .

Bidirectional associative memories (BAMs) have been extensively applied in auto and heteroassociative learning. However, the research on the hardware implementation of BAM neural networks is relatively few. Memristor, a nanoscale synaptic-like element, provides a new perspective for the circuit implementation of neural networks. In this work, we improve a threshold memristor bridge circuit (T-MBC) and design a novel memristive bidirectional associative memory (MBAM) network circuit on this basis. T-MBC is capable to achieve positive, negative, and zero synaptic weights without any switches, inverters, transistors, and current–voltage conversion processes. The validity of T-MBC is illustrated by PSPICE. MBAM has a simpler structure and gains excellent effects in flexibility, and reconfigurability. Besides, it is shown that MBAM can be trained to recall both disturbed binary images and incomplete/noisy grey-scale images robustly. Meanwhile, a more complex application of emotion classification based on MBAM is also accomplished. Experimental results verify the effectiveness of the MBAM neural network and demonstrate that the MBAM neural network has high recognition accuracy and strong noise immunity.

Magnetoresistive sensors are considered as part of bridge circuits for measuring magnetic field strength and electric current value. Normalized or relative expressions are introduced to change the resistance of the sensor and the measured bridge voltage to increase the information content of the regime to provide the possibility of comparing the regimes of different sensors. To justify these expressions, a geometric interpretation of the bridge regimes, which leads to hyperbolic straight line geometry and a cross ratio of four points, is given. Upon a change in the sensor resistance, the bridge regime is quantified by the value of the cross ratio of four samples (three characteristic values and the current or real value) of voltage and resistance. The cross ratio, as a dimensionless value, is taken as a normalized expression for the bridge voltage and sensor resistance. Moreover, the cross ratio value is an invariant for voltage and resistance. The proposed approach considers linear and nonlinear dependences of measured voltage on sensor resistance from general positions.Se analizează utilizarea senzorilor magnetorezistivi ca parte componentă a circuitelor în punte pentru măsurarea intensității câmpului magnetic și a curentului electric. Pentru a spori capacitatea informativă a regimului de lucru, a oferi posibilitatea de a compara regimurile diferitor senzori, sunt introduse expresii normalizate sau relative pentru schimbarea rezistenței senzorului și a tensiunii măsurate a punții. Pentru a fundamenta aceste expresii, se utilizează interpretarea geometrică a regimurilor de punte, ceea ce duce la geometria hiperbolică a liniei drepte și la raportul complex a patru puncte. Atunci când rezistența senzorului se schimbă, regimul de punte este determinat cantitativ de valoarea raportului complex a patru eșantioane (trei valori caracteristice și valoarea actuală) a tensiunii și rezistenței. Raportul complex, ca mărime adimensională, este luat ca expresie normalizată pentru tensiunea punții și rezistența senzorului. În plus, valoarea raportului complex este un invariant pentru tensiune și rezistență. Abordarea propusă ia în considerare, din punct de vedere general, dependențele liniare și neliniare ale tensiunii măsurate de rezistența senzorului.

We propose a novel circuit for the fractional-order memristive neural synaptic weighting (FMNSW). The introduced circuit is different from the majority of the previous integer-order approaches and offers important advantages. Since the concept of memristor has been generalized from the classic integer-order memristor to the fractional-order memristor (fracmemristor), a challenging theoretical problem would be whether the fracmemristor can be employed to implement the fractional-order memristive synapses or not. In this research, characteristics of the FMNSW, realized by a pulse-based fracmemristor bridge circuit, are investigated. First, the circuit configuration of the FMNSW is explained using a pulse-based fracmemristor bridge circuit. Second, the mathematical proof of the fractional-order learning capability of the FMNSW is analyzed. Finally, experimental work and analyses of the electrical characteristics of the FMNSW are presented. Strong ability of the FMNSW in explaining the cellular mechanisms that underlie learning and memory, which is superior to the traditional integer-order memristive neural synaptic weighting, is considered a major advantage for the proposed circuit.

A discrete GaN power transistor’s substrate is typically connected to its source electrode. However, on the GaN-on-Si power IC platform, the high-side transistor (HS-transistor) and low-side transistor (LS-transistor) share a common substrate that cannot be simultaneously connected to both source electrodes of the two transistors. Thus, the termination of the common substrate remains an undecided issue. In this work, comprehensive TCAD simulations are exploited to reveal the influences of various substrate termination schemes. It is found the common substrate inevitably leads to severe degradation in the dynamic ${R} _{\mathrm{ ON}}$ due to back-gating effects. The mechanisms for the degradations vary with the substrate termination scheme, and will be discussed in detail. To address these issues, we propose a new GaN power IC platform on an engineered bulk silicon substrate, and study the new platform with TCAD simulations. The proposed platform provides a local electrical substrate (a p+ island) for each GaN power transistor. The source electrode of each GaN transistor is connected to its local electrical substrate, while all devices share a common mechanical substrate. The junctions between the local substrates and the underlying n-layer provide an effective isolation between GaN transistors. The back-gating effects are completely suppressed for the GaN integrated bridge circuit.

In variable parameter transducers, the small change in passive parameters such as resistance, capacitance, and inductance, generally changes linearly with the process variable in process plant. The classical method of measurement of passive parameters generally uses an ac bridge circuit. However, this type of bridge measurement technique suffers from errors due to the effect of stray capacitances in between bridge output terminals and ground. These errors can be minimized by using the Wagner-earth technique, but the limitation is the repetition of bridge balance, which is required in every observation so that continuous measurement is not possible, which is the basic needs of a transducer. In this article, a modified De’ Sauty bridge network has been developed by using a high-gain operational amplifier to minimize the stray capacitances in case of measurement of the small change in resistances or capacitances. A potentiometer has been used to adjust the sensitivity of the bridge. For a particular value of bridge sensitivity factor, the change of passive parameters of sensor equivalent and the change of actual process variables have been observed and found good linearity and repeatability.

Nowadays most used technology is Wireless sensor network which provides increasing efficiency of data collection and processing, which controls the flow of data applications. Rectenna is a device that converts Radio waves into Electrical signal by utilize of rectifying bridge circuit which is directly connected to the normal antenna. The common purpose of antenna is used in transmission of microwave energy. The purpose of rectenna is to receive RF energy from the atmosphere and transmit through the circuit. This provide high efficiency while conversion of microwaves into the Electrical energy.

High-frequency bipolar high-voltage pulsed electric field can be used in tumor ablation to uniform the electric field distribution in the ablated region and inhibit muscle contraction effectively. Developing a high-frequency bipolar pulsed power generator (HBPPG) with wide range of specifications, such as voltage magnitude, waveform, repetition rate, and pulsewidth, is of great significance for promoting the clinical application of irreversible electroporation. Hence, in this article, a novel modular high-voltage HBPPG circuit topology is proposed for such application. Each module consists of an H-bridge and an isolated inductor. Theoretical analysis, simulation, and experimental results show that this generator perfectly combines the advantages of solid-state Marx and bridge circuit, with high stability and redundancy. The pulse frequency, pulse duration, and waveform can be flexibly adjusted by a controller software algorithm according to load parameters. The viability of the proposed HBPPG is demonstrated by PSpice simulation and equal-scale prototype. The key parameters of the developed HBPPG are as follows: voltage amplitude up to ±10 kV with 500 ns–5 μ s pulsewidths, 500 kHz within the burst, and 10 kHz within the continuation limited by the input high-voltage dc power supply. All the pulse parameters can be programmed arbitrarily.

Earlier, when studying with the help of instrument-technological simulation of the silicon-on-insulator field-effect Hall sensor (SOI FEHS) in the partial depletion mode, the effect of increasing its magnetic sensitivity was discovered. In this paper, we study the parameters of SOI-FEHS samples in various operation modes to experimentally confirm the discovered effect. To increase the measurement accuracy in the partial depletion mode, the FEHS design with a split drain is used. The optimal values ​​of the load resistances of the bridge circuit are determined. An analysis of the results of studying the experimental SOI-FEHS samples shows that the peak of the increased magnetic sensitivity is observed in the partial depletion mode. At a load resistance of 1 MΩ and a supply voltage of –9 V, the maximal magnetically induced signal approximately triples in the partial depletion mode compared with the full depletion mode. When recalculating the ΔU voltage difference on the load resistances to the magnetic sensitivity, the specific magnetic sensitivity of the FEHS in the partial depletion mode can reach values ​​of about 105 V/(A T), which is significantly higher than that of semiconductor Hall elements.

Pulsed eddy current testing is widely used because of its richness in spectral components. However, the degrading sensitivity as lift-off increases poses a challenge to its application in thick insulation or buried structures and weld areas. In the transmitter-receiver probe, self-impedance (offset) of receiver coil dominates the output signal, reducing the signal-to-noise ratio, especially at high lift-off. This limits the subsequent amplification of the output signal by the signal conditioning circuit. In practice, bridge-based measurements are used to mitigate this challenge but result in small linear range input-output characteristics. Electromagnetic interference and stray capacitance effects also cause measurement errors. This paper investigates a modified Maxwell’s inductance bridge based on operational amplifier configuration for high lift-off testing. The receiver coil self-impedance is removed to improve signal-to-noise ratio and to make output signal proportional to impedance change only. Experiments are performed to evaluate the performance of the circuit in crack detection. The results show improved signal-to-noise ratio with maximum linearity deviation of 0.30%, and a higher crack detection sensitivity at 30mm high lift-off, in comparison to the conventional bridge circuit with maximum linearity deviation of 0.53%.

Объект исследования – мощный современный импульсный источник вторичного питания резонансного типа с корректором коэффициента мощности и подстройкой Ð²Ñ‹Ñ Ð¾Ð´Ð½Ð¾Ð³Ð¾ напряжения для дальнейшей разработки одного из блоков подобного улучшенного устройства. Цель работы – разработать следующие принципиальные ÑÑ ÐµÐ¼Ñ‹: ÑÑ ÐµÐ¼Ð° Ð²Ñ Ð¾Ð´Ð½Ð¾Ð¹ части с защитой от ÑÐµÑ‚ÐµÐ²Ñ‹Ñ Ð¿ÐµÑ€ÐµÐ½Ð°Ð¿Ñ€ÑÐ¶ÐµÐ½Ð¸Ð¹ и Ð¿Ð¾Ð¼ÐµÑ Ð¸ ограничением пускового тока; ÑÑ ÐµÐ¼Ð° блока корректора коэффициента мощности с составным ключом. В результате исследования изучались вопросы перестройки на другие рабочие напряжения и особенности работы инвертора, а также применяемые Ñ‚ÐµÑ Ð½Ð¾Ð»Ð¾Ð³Ð¸Ð¸ снижения нагрузки сети. Исследование Ð¿Ñ€Ð¾Ð¸ÑÑ Ð¾Ð´Ð¸Ð»Ð¾ экспериментальным путём с последующим соотнесением с теоретическими данными, извлечёнными из Ð°Ð²Ñ‚Ð¾Ñ€Ð¸Ñ‚ÐµÑ‚Ð½Ñ‹Ñ Ð¸ÑÑ‚Ð¾Ñ‡Ð½Ð¸ÐºÐ¾Ð². Поскольку сейчас требования к качеству питания и возможностям Ð¿Ð¸Ñ‚Ð°ÑŽÑ‰Ð¸Ñ ÑƒÑÑ‚Ñ€Ð¾Ð¹ÑÑ‚Ð² довольно высоки, такие устройства применяются в промышленном оборудовании, ÑÐ¿ÐµÑ†Ð¸Ð°Ð»ÑŒÐ½Ñ‹Ñ Ð¸ÑÑÐ»ÐµÐ´Ð¾Ð²Ð°Ñ‚ÐµÐ»ÑŒÑÐºÐ¸Ñ ÑƒÑÑ‚Ð°Ð½Ð¾Ð²ÐºÐ°Ñ Ð¸ Ñ‚ÐµÐ»ÐµÐºÐ¾Ð¼Ð¼ÑƒÐ½Ð¸ÐºÐ°Ñ†Ð¸Ð¾Ð½Ð½Ñ‹Ñ ÑÐµÑ‚ÑÑ . Результатом работы являются достигнутые цели, т. е. один из блоков. Данные результаты стали начальным этапом разработки всего устройства., The object of study is a powerful modern switching resonant-type secondary power supply with a power factor corrector and output voltage adjustment for further development of one of the blocks of such an improved device. The purpose of the work is to develop the following schematic diagrams: input circuit diagram with protection against mains surges and interference and inrush current limitation; block diagram of the power factor corrector with a composite key. As a result of the study, the issues of restructuring to other operating voltages and features of the inverter, as well as the technologies used to reduce the network load, were studied. The study took place experimentally with subsequent correlation with theoretical data extracted from authoritative sources. Since the requirements for power quality and the capabilities of power devices are now quite high, such devices are used in industrial equipment, special research facilities and telecommunication networks. The result of the work is the achieved goals, i. e. one of the blocks. These results became the initial stage in the development of the entire device.

Объектом исследования являются Ñ Ð°Ñ€Ð°ÐºÑ‚ÐµÑ€Ð¸ÑÑ‚Ð¸ÐºÐ¸ современной элементной базы ÐºÐ»ÑŽÑ‡ÐµÐ²Ñ‹Ñ Ñ‚Ñ€Ð°Ð½Ð·Ð¸ÑÑ‚Ð¾Ñ€Ð¾Ð² из Ñ€Ð°Ð·Ð»Ð¸Ñ‡Ð½Ñ‹Ñ Ð¼Ð°Ñ‚ÐµÑ€Ð¸Ð°Ð»Ð¾Ð²: карбид кремния, нитрид галлия, кремний. Рассмотрены ÑÑ ÐµÐ¼Ñ‹ ÐºÐ»ÑŽÑ‡ÐµÐ²Ñ‹Ñ ÑƒÑÐ¸Ð»Ð¸Ñ‚ÐµÐ»ÐµÐ¹ мощности: D, E, DE, FE1 и FE2. Целью исследования является возможность повышения энергетической эффективности ключевого усилителя мощности за счёт Ð¿ÐµÑ€ÐµÑ Ð¾Ð´Ð° на элементную базу из Ð½Ð¾Ð²Ñ‹Ñ Ð¼Ð°Ñ‚ÐµÑ€Ð¸Ð°Ð»Ð¾Ð². В результате исследования была проанализирована современная элементная база для Ð½Ð¸Ð·ÐºÐ¸Ñ Ð¸ Ð²Ñ‹ÑÐ¾ÐºÐ¸Ñ Ñ‡Ð°ÑÑ‚Ð¾Ñ‚ в диапазоне от 1 кГц до 10 МГц. Для оценки достоверности результатов было проведено имитационное моделирование, при котором значения формирующего контура и нагрузки были рассчитаны для усилителя классов D и DE с учётом Ñ Ð°Ñ€Ð°ÐºÑ‚ÐµÑ€Ð¸ÑÑ‚Ð¸Ðº Ð²Ñ‹Ð±Ñ€Ð°Ð½Ð½Ñ‹Ñ ÐœÐžÐŸ и IBGT транзисторов. Задание на выпускную квалификационную работу выполнено в полном объёме., The subject of the graduate qualification work is the characteristics of the modern element base of switch transistors made of different materials: silicon carbide, gallium nitride, silicon. Circuits of switching mode power amplifiers: D, E, DE, FE1 and FE2 are considered. The given work is devoted to the possibility of improving the energy efficiency of a switching mode power amplifier by switching to an element base of new materials. As a result of the study the modern element base for low and high frequencies in the range from 1 kHz to 10 MHz was analyzed. To assess the validity of the results a simulation was carried out, in which the values of the shaping circuit and load were calculated for an amplifier of classes D and DE, taking into account the characteristics of the selected MOS and IBGT transistors.

In our earlier work we proposed a method to measure the temperature of the coal pipe of Coal Mills in PF Boiler by a continuous basis, In order to achieve, accurate measurements of coal pipe temperature, using the resistive transducers like resistance temperature detector (RTD), the small resistance changes linearly with temperature, but resistance measurement by using RTD using normal Wheatstone bridge circuit would have errors for the stray capacitance presents in between bridge nodal points and the ground. Hence, by the use of a modified operational amplifier based Wheatstone bridge network, these effects can be minimized. The bridge performance has been studied experimentally with RTD. It has been observed good linearity, repeatability and variable sensitivity over the wide range of temperature.

High temperature electronics, micro-electro-mechanical systems (MEMS) and sensors that are able to operate between 300°C to 600°C have broad applications in harsh environments such as oil/gas exploration, geothermal development, industrial manufacturing processes, and space exploration. 4H-silicon carbide (SiC) is a good material for harsh environment applications because of its wide bandgap, high carrier mobilities, excellent thermal and chemical stabilities, and high breakdown electric field strength. Several 4H-SiC devices and integrated circuits have been studied in this work, including p-n diodes, p-n diode temperature sensors, bridge rectifiers, and bridge circuits for differential capacitive pressure sensors.4H SiC p-n diodes from room temperature to 600°C have been demonstrated with theoretical study, simulation, fabrication, and characterization. The fabricated 4H-SiC p-n diodes show turn on voltages from 2.6 V to 1.3 V which match well with the technology computer-aided design (TCAD) simulation results from 2.7 V to 1.45 V when temperature increases from 17°C to 600°C. Planar-integrated 4H-SiC diode bridge rectifier circuits are analyzed, simulated by SPICE (Simulation Program with Integrated Circuit Emphasis), fabricated and characterized. Experimentally, fabricated rectifiers are functional up to 500°C with voltage conversion efficiencies of 73.6% at room temperature and 89.1% at 500°C. High-performance temperature sensors from 17°C to 600°C by using circular-shape 4H-SiC p-n diodes are analyzed, simulated by TCAD Sentaurus, fabricated and tested. The 4H-SiC p-n diode temperature sensors achieve high sensitivities of 2.9 mV/°C at 0.1 μA and 4.7 mV/°C at 1 mA in a wide temperature range from 17°C to 600°C.Finally, planar integrated 4H-SiC diode bridge circuits for differential capacitive pressure sensor transduction are investigated. The working principle of the transduction circuit is derived. The circuit is simulated by SPICE, fabricated and tested with a sensitivity of 9.3 mV/pF at 1 MHz and a 3dB cut-off frequency of 2.5 MHz.These results show great potential for 4H-SiC devices and circuits working in harsh environment electronics, MEMS and sensing applications.

The paper present the results of studying the process of forming the commutating voltage of a compensation converter, implemented to the three-phase combined bridge circuit, are presented. It is shown that the transition of the converter from the non-compensation mode of operation to the compensating one requires the research of three modes: 1) starting, in which the commutating voltage has an insignificant value, 2) transient mode characterized by increased values of the commutating voltage, and 3) compensating. The results of the study of the process of forming the commutating voltage in three situations of the starting mode are given because the volume of publication is limited. A conclusion is made about the optimal conditions for recharging the capacitors of the commutating link.

Nowadays, condition monitoring of gearboxes is based on analyzing vibration signal (mostly acceleration, velocity; fewer strain) measured from mechanical components or on analyzing acoustic emission and temperature data. Strain sensors are rarely used because of their high cost, mounting difficulties and their sensitivity harsh environment. They are based on strain gage technology which implements ‘Wheatstone Bridge Conditioner’ to be able to measure strain values. This bridge circuit, unfortunately, becomes non-linear out of the measurement range resulting in significant errors. To avoid those errors, a new technology of piezoelectric strain sensors, relatively new to condition monitoring, emerges: they have good precision since the accuracy is improved and provide good results especially when attempting to do measurements at extremes of the range. In this work, a piezoelectric strain sensor mounted on an industrial planetary gearbox (PG) in vertical direction is used to acquire time domain signals. This latter is introduced to focus on the importance of the new time domain representation of a gearbox dynamic behavior by a such sensor. Finally, an analysis of the RHM sensor time domain data is conducted to identify the PG characteristic frequencies.