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Pulse-width voltage regulators are gaining increasing use in industry, especially in variable speed drives. At the same time, little research has been done in the field of electromagnetic compatibility (spectral composition of current consumption). The aim of the study is to determine, using computer simulation, the nonsinusoidality of the current consumption with an RL-load from a voltage regulator based on a pulse-width conversion. The study of the spectral composition of the supply current of an active-inductive load with a pulse-width voltage regulator was carried out using the provisions of the theory of electrical circuits of sinusoidal and non-sinusoidal periodic current using computer simulation. To analyze the spectral composition of the supply current of the RL-load with the selected voltage regulator, a simulation computer model was created, which consisted of a three-phase power supply and an RL-load, a rectifier with a transistor switch. The regulation of the applied voltage to the consumer was carried out according to the principle of a pulse-width voltage converter. As a result of studying a model of a regulated power supply based on a pulse-width converter and working on an active-inductive load, it was found that even with an initial voltage of the fundamental harmonic regulator of 34 V, the nonsinusoidality of the consumption current is 0.19%, which corresponds to the quality standard for electricity. It is advisable to use this regulator for a controlled electric drive of ventilation systems with an increased slip motor, for example, in "Climate-4M" units. Key words: semiconductor voltage converter, pulse-width converter, higher harmonics, RL-load

Variation in the ambient temperature deteriorates the accuracy of a resolver. In this paper, a temperature-compensation technique is introduced to improve resolver accuracy. The ambient temperature causes deviations in the resolver signal, therefore, the disturbed signal is investigated through the change in current in the primary winding of the resolver. For the proposed technique, the primary winding of the resolver is driven by a class-AB output stage of an operational amplifier (opamp), where the primary winding current forms part of the supply current of the opamp. The opamp supply-current sensing technique is used to extract the primary winding current. The error of the resolver signal due to temperature variations is directly evaluated from the supply current of the opamp. Therefore, the proposed technique does not require a temperature-sensitive device. Using the proposed technique, the error of the resolver signal when the ambient temperature increases to 70 °C can be minimized from 1.463% without temperature compensation to 0.017% with temperature compensation. The performance of the proposed technique is discussed in detail and is confirmed by experimental implementation using commercial devices. The results show that the proposed circuit can compensate for wide variations in ambient temperature.

In view of the problem of serious water accumulation and frequent accidents in the coal mine mining area, the distribution range of Yuzhou Shenhuo Kuanfa Mining Coal (hereinafter referred to as Kuanfa Coal Mine) is detected by transient electromagnetic method. The transient electromagnetic emission wire frame is 480m × 480m, frequency is 8Hz, power supply current is 16A. The research conclusion preliminarily determines that the transient electromagnetic and controllable source audio earth electromagnetic method is applicable for the exploration of the mined space area in Yuzhou mining area, and the construction parameters provide a reliable reference for the accurate exploration of the mined space area in Kuanmining area.

High capacity last-level caches (LLCs) are being used to help alleviate the growing speed gap between the processor and main memory. However, traditional CMOS based memory technologies (SRAM, DRAM, et al.) for such LLCs consume high static power. Non-volatile memory such as STT-MRAM has been proposed as a low power solution for LLCs. Nevertheless, the high write current induces a so-called “supply current threshold” issue and limits the maximum number of bit-cells that can be written concurrently in one cycle in an STT-MRAM cache. This drawback significantly decreases the bandwidth of the STT-MRAM cache compared with SRAM. In this work, we present a hardware implementation of NAND-like spintronic memory (NAND-SPIN) LLC for the first time. By exploiting the unique erase-then-program operation for writing NAND-SPIN, we propose an adaptive buffer entry (ABE) write policy for each cache write access. Instead of writing a fixed number of bits sequentially, our method adaptively extends the write data length under a fixed maximum cache supply current. Compared to existing STT-MRAM caches, ‘ABE’ can achieve 70% performance improvements on average. Compared with the conventional early write terminate (EWT) policy, ‘ABE’ can save 33% write energy on average with negligible hardware overhead.

No presente trabalho foram realizadas simulações visando comparar os resultados obtidos, em termos de composições dos produtos, com aqueles encontrados na literatura para esse tipo de reação, e ainda avaliar a influência desses resultados na capacidade energética dos produtos. As simulações foram realizadas com o auxílio do software de simulação Aspen Plus®, simulando a operação em um Reator de Gibbs. As condições de pressão e temperatura simuladas, que corresponderam àquelas usadas na literatura para viabilizar a comparação de resultados, foram alteradas de modo a se identificar a influência das mesmas no processo. Os dados gerados nas simulações foram analisados e a partir deles foi possível determinar como condições ideais de pressão e temperatura 382 ºC e 0,14 MPa; além da composição ideal de cada polímero a ser alimentada no reator (51% PE, 41% PP e 8% PS); a autossuficiência do processo, em termos energéticos, utilizando a corrente gasosa dos produtos da pirólise para gerar energia capaz de fundir a corrente de alimentação do reator e suprir a necessidade energética do mesmo e a capacidade do sistema de produzir trabalho útil, via aplicação de um ciclo Otto, no valor de 3,615 kW/kg.

The digital tube displays abnormally during the use of a certain computer. Through analysis, it is found that the abnormal current display of the digital tube is caused by abnormal current sampling and amplification. The silver layer of the R2 resistance surface electrode inside the sensor is corroded and disconnected by sulfur-containing substances, causing the resistance to increase and fail, resulting in an abnormal zero point, and finally the current display of the digital tube is abnormal. Replace the sensor, the current value displayed by the digital tube is consistent with the output current value of the power module, and the problem is solved. The research in this article enriches the research on power supply current sampling, and provides theoretical support and basis for subsequent development and design and solving practical problems.

Improving the cycle time through the development of techniques and enhancement of equipment aims customer satisfaction. Repetitive mounting and demounting on an evaluation board is one of the aspects that cause high cycle time. The open-top socketed evaluation board will be used for bench testing and fault localization eliminating the mounting and demounting process on the failure analysis flow of a specific GaAs radio frequency device and lessen the cycle time from sample preparation for failure verification until fault localization. The open-top socketed evaluation board achieved electrical specification parameters by the datasheet including supply current, gain, input and output return loss; matched emission sites on fault localization by LEM; eliminated mounting and demounting process, and saved 50.71 % of the processing time from sample preparation for failure verification up to sample preparation for physical analysis.

This paper presents control of switching frequency twice the output frequency for a matrix converter in induction heating application. The duty cycles of the matrix converter are derived, and the operating waveform and the switching pattern are indicated. The effectiveness of the proposed control is verified by the distortion rate of power supply current of simulations and experiments.

It is well known that fail dies that exhibit obvious static power supply leakage current have a higher success of finding a defect, hence, a higher likelihood to be selected for failure analysis. When presented with choices, fail dies that exhibit similar supply current to reference are omitted. Valuable defect learnings are lost as a result. The feasibility of applying an Artificial Neural Network to predict failure analysis success has been demonstrated in a previous report. Besides automating the fail dies selection process, more importantly, dies which could yield valuable findings but neglected otherwise by convention, can be identified. We extend the previous proof-of-concept to study the effects of learning iterations, learning rate and the number of nodes on prediction accuracy in this work. More experimental results which include an actual case study will also be presented to substantiate the value of machine learning in this application.

Serial powering is the baseline choice for the upgrade of the CMS pixel detector for the High Luminosity LHC. The first results with the four-chip prototype pixel detector modules based on the demonstrator 65 nm CMOS technology RD53A chip are presented. The serially powered chain is operated at a constant supply current and the regulation is performed on-chip using a shunt low-dropout regulator (SLDO). Chips on each module are powered in parallel to prevent single-point failures. The SLDO behaviour in the system is presented as well as relevant differences in the behaviour compared to single chips. The noise levels are measured in pixels of a module in a serially powered chain and no increase is observed compared to a single module or the reported noise levels for a single chip., Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 978, ISSN:0168-9002, ISSN:1872-9576

Most battery-powered systems require measurement of the battery's state of charge, (SOC). A straightforward way to determine SOC is to keep track of the current flowing in and out of a battery, a method known as coulomb counting. Compared to other methods such as voltage or impedance monitoring, coulomb counting is simple to implement, does not require complex algorithms and is independent of cell chemistry. However, coulomb counters must operate continuously and essentially integrate forever; traditionally, their relatively high power consumption (several tens of µA e.g. [1]–[3]) and susceptibility to drift in the presence of offset have prevented their more widespread use.

Design and manufacturing of electronic modules is a difficult process - on the one hand there arises a problem of developing the inner circuitry of best possible performance, on the other hand -building it at the lowest possible price. When it comes to cutting expenses on production, even the smallest changes in materials can critically influence the total manufacturing costs. The paper introduces a method of detecting certain module’s overheating levels without a necessity of using temperature sensors - devices generating unnecessary fabrication expenses. The assessment of temperature can be performed with the use of supply current waveform analysis - particular changes in current function caused by overheating may be processed and correlated with a certain temperature. Finding those differences in supply waveforms and classifying them may be done with either analytic methods or heuristic algorithms.

This paper presents the results of computer simulation of optimal dynamic modes of thermoelectric device for cryodestruction. The optimal time function for controlling the supply current to thermoelectric micromodule in a device for cryodestruction is determined, which ensures given cyclic temperature effect on the local area of human body.Keywords: computer simulation, optimal dynamic mode, cryodestruction, thermoelectric cooling.

The paper presents the method for the estimation of the energy consumption of the low-power microcontroller-based devices. Due to high dynamics of the changes of the supply current of the tested devices during the operational cycle, the consumed energy estimation is not easy. In order to avoid disadvantages of known methods, the charge balancing method was employed similarly like in some types of A/D converters.

The harmonic balance finite element method for two dimensional periodic magnetic field in a conductive ferromagnetic medium is formulated. To convert of partial differential equation system into the system of nonlinear algebraic equations the weak formulation of Galerkin method is used. Structural steel and silicon steel with different magnetic properties and various electrical conductivity are studied. It is described how to take into account the nonlinear properties of medium in mathematical model. The spectrum of supply current and flux density on the surface and inside the medium were computed provided the sinusoidal voltage fed. The dependencies of the amplitudes of high harmonics versus the steel properties and amplitude of the first harmonic of magnetic flux density at the surface of medium are presented. Представлено метод гармонічного балансу сумісно з методом скінченних елементів для двовимірного магнітного поля в електропровідному феромагнітному середовищі. Для перетворення диференціального рівняння в часткових похідних до системи нелінійних алгебраїчних рівнянь використовувався метод Гальоркіна в слабкому формулюванні. Досліджувалися конструкційна та легована сталь із різними магнітними властивостями та різною електропровідністю. Описано врахування нелінійних властивостей у математичній моделі. Розраховано спектри струму живлення та магнітної індукції на поверхні та всередині середовища за умов живлення синусоїдальною напругою. Представлено залежності амплітуд вищих гармонік від властивостей сталі та амплітуди першої гармоніки магнітної індукції на поверхні середовища. Сформулирован метод гармонического баланса совместно с методом конечных элементов для двумерного магнитного поля в электропроводящей ферромагнитной среде. Для преобразования дифференциального уравнения в частных производных в систему нелинейных алгебраических уравнений использовался метод Галеркина в слабой формулировке. Исследовались конструкционная и легированная сталь с различными магнитными свойствами и различной электропроводностью. Описан учет нелинейных свойств в математической модели. Рассчитаны спектры тока питания и магнитной индукции на поверхности и внутри среды при условиях питания синусоидальным напряжением. Представлены зависимости амплитуд высших гармоник от свойств стали и амплитуды первой гармоники магнитной индукции на поверхности среды.

Issues of generation high-frequency harmonics is spectrum of power supply current and output frequency converter voltage. Authors make of ways to increase compatibility between power supply network and electric drives.

A bulk-linearised composite MOSFET is presented, with an extended linear range and an equivalent saturation voltage of up to several hundred mV even in weak inversion. Some preliminary measurements are presented as well as a 300 MΩ equivalent resistor, with almost a 1 V quasi-linear range. A low frequency, 28 dB gain, biomedical bandpass filter/amplifier is also shown, taking advantage of the linearised MOSFETs to consume only 16 nA of supply current.

An unexpected failure occurred during Latch-Up test of a 22FDSOI chip which had 3.3V general purpose I/Os implemented using 1.8V compliant devices. The high supply current flowing was not a real LU failure but due to triggering of RC clamp during negative current injection on nearby I/Os. The pseudo Latch-Up is presented along with methods to ensure robustness of 3.3V clamp design structures

Gammon India limited is one of the leading tower companies with exposure in extra high voltage transmission line and distribution projects since 1984. They have in-house facility for design, testing and tower manufacturing capacity (110,000 TPA) and have supplied towers/structure over 6, 00,000 metric tons including 87,000 metric tons to different countries. They are ISO certified for design, testing, manufacturing and turnkey projects. The various types of cranes utilized in transmission Tower Company like goliath or gantry crane, electrical overhead travelling crane and hydra (JCB) to shift unprocessed materials, semi-process and end products from one station to another station. The goliath/gantry cranes are placed in unprocessed and processed yard and it is used to transfer unprocessed materials from raw yard to different machine in machine shop-1 and machine shp-2 also it transfer end products from steel yard to different automobile vehicles like box truck, recreational vehicle, camper etc. The high breakdown occurs in goliath/gantry cranes due to breakage of supply current trolley cable, so high maintenance and production cost is involved and after every two years supply current trolley cable is replaced by new one. In this paper an entire though is given as regards how to optimize breakdown and production loss by implementing bus-bar/current collector system on gantry/goliath crane. The current collector or bus-bar system is employed to provide three phase current to different motors of gantry/goliath crane. This paper presents evolving a maintenance optimization of gantry/goliath crane in supply current cable trolley system.

In vast majority of operational amplifiers, output transistor current is not independently accessible. Op-Amp power supply current sensing is a simple technique for detecting output transistor current from the Op-Amp power supply leads. This technique was first introduced in 1979 to implement voltage controlled current sources and current controlled current sources [1]. It has been implemented by connecting current mirrors to Op-Amp supply leads and makes possible to gain access to output transistor current separately. © 2019, Springer Nature Switzerland AG.

This paper presents a 36V JFET -input bipolar operational amplifier with an unprecedented combination of DC precision (150µV offset, 1.5 µV/°C drift) and high speed (48MHz GBW, 160V/µs slew-rate). The high slew-rate is obtained using the well-known slew-boosting method. However, conventional slew-boost circuits can cause excessive power consumption when the amplifier inputs are overloaded and the output hits the rail. Therefore, a dedicated protection circuit was added that detects such an overload condition, and limits power consumption in this condition.

This work presents a methodology that correlates the supply current of a smart device to its functional characteristics in order to detect a manufacturing or a security anomaly in IoT devices. It is proven that awareness of the typical operation of a smart device via functional parameters (like the supply current), may offer valuable security indicators since any deviation from normal operational boundaries may be indicative of a security compromise or a functional anomaly. The paper offers the results from two experiments that prove this assumption and contribute towards an holistic security approach for the era of the Internet of Things (IoT).

It is well known that fail dies that exhibit obvious static power supply leakage current have a higher success of finding a defect, hence, a higher likelihood to be selected for failure analysis. When confronted with choices, fail dies with supply current similar to reference will be omitted. Valuable defect learnings are lost as a result. In this work, an artificial neural network is developed to perform the task of predicting failure analysis success confidence level on fail dies. The input parameters are dynamic current measured from multiple power supplies and an output accuracy of 80% on average is achieved. Besides an enhanced productivity from automating the dies selection process, more importantly, fail dies which are otherwise neglected, can be identified. This first demonstration is a new milestone for the application of machine learning to the failure analysis domain.

This paper presents the development of a method for condition monitoring and online fault detection on proportional directional valves. The systems that such valves are part of might be sensitive for unexpected maintenance or long duration stops. Consequently, the implementation of a fault detection and monitoring system can reduce maintenance costs and increase safety. The method is based on monitoring both the valve supply current and spool position related to the spool positioning control signal. Therefore, it is applicable for valves with embedded electronics including spool position measurement and internal controller. The supply current and spool position behavior depends on the friction, flow forces, solenoid current, and valve closed loop controller performance. Furthermore, valve static and dynamic characteristics are influenced by the spool size, overlapping and manufacturing tolerances. The effectiveness of the method to monitor and detect faults in valves with different sizes and constructive parameters is shown experimentally using five different proportional valves. The proposed method requires reference parameters characterizing the valve operation without faults. Standard tests are proposed to determine healthy valve parameters. For the method valuation and validation, experimental results with the valve operating under healthy conditions and with induced faults were compared. Faults were added in a way to represent spool locking and increase of friction forces between the spool and sleeve. The obtained results show the capability the method for the detection of faults classified as severe even if the valve controller attempts to compensate the faulty behavior.

A built-in test circuit is proposed to detect an open defect in a CMOS IC by means of appearance time of dynamic supply current of the IC. A layout of an IC embedding the test circuit is designed. It is shown by Spice simulation that an open defect in the IC can be detected with the test circuit.

In mix-signal circuits' design, there may some scan safe points missing which leads quiescent supply current (iddq) increase and also scan patterns fails. Normally designer will check them manually by waveform in backend level or design code which may be inefficiency and tricky. With this method designer can find possible missing points in RTL level and mix signal simulation which reduces the test power, speeds up the flow and increases the quality of test result.