Circuit Scheme Research Articles

Research and Practice on Course Design of Medical Physiology and Engineering under the Background of Cultivating Innovative Talents

This paper takes the medical electronics foundation course of medical imaging as an example., Through the introduction of four typical circuit design requirements and design methods, discusses the purpose and significance of increasing the course design of medical physiological engineering courses under the background of cultivating innovative talents., The method of curriculum design in medical courses, the main problems to be solved and the specific design scheme and results. According to the task and design index requirements of the selected topic, students determine the requirements of the overall design scheme, and draw the system block diagram of the overall scheme (pre-design stage); Analysis, input design, compilation and simulation of the underlying unit circuit; Draw the schematic diagram of the top circuit with the correctly compiled module of the bottom unit, and carry out compilation, debugging and simulation test. Write design report. Through course design, students can learn to search information, compare schemes, calculate circuit parameters, design circuit schematic diagram, make printing board, weld and debug components, test circuit performance, so as to improve students’ ability to analyze and solve practical problems. After the completion of the overall design, select the right device, apply the design scheme, complete the circuit board production, one step in place. At the same time, virtual and real contrast.

Timing Circuit Design Based on Sequential Logic and Micro-processing Technology

According to the need of equipment testing, the paper presented the overall scheme of timing circuit and the wiring diagram of hardware circuit, and also designed the indicator circuit, the timing software and the band switch circuit. Then modular design concept and function decomposition method were adopted, and the time sequence step-by-step technology and safety isolation technology were used to solve the difficulty and credibility of acquiring multi-functional components, multi-system modules and complex multi-channel correlated signal interference problem. Finally, the off-line debugging was carried out. The results show that the technology can test the functions and performance indexes of the plug-in board comprehensively and completely, realize the functions of depth setting system debugging, extension testing and fault precise location, and shorten the maintenance and detection time.

Analysis of Abnormal Causes and Renovation Measures for Voltage Monitor Board of Light Triggered Thyristor in Zhaoqing Converter Station

In September 2018, 25 thyristor voltage monitor (TVM) boards of the Y4 valve of Pole 2 in Zhaoqing converter station did not have feedback signal. In order to make clear the root cause of this incident, the paper draws the detailed schematic diagram of the TVM board of converter valve in Zhaoqing station, and then studies the working principle of the TVM board and its feedback signal circuits, and analyzes the information interchange among all the functional modules. The pulse generation of positive voltage signal, negative voltage signal and overvoltage signal of the board are dissected. Then the equivalent circuit of each functional module is established to deduce the real reason of TVM board abnormality by quantitative calculation. Then the optimized scheme of TVM board circuit is proposed. Finally, comparative tests between the original circuit and the optimized circuit are carried out with the power supply of 459V RMS sinusoidal voltage and 7kV magnitude overvoltage respectively. The results show that the analysis of the TVM board working principle is correct, and the optimized scheme of TVM board circuit is effective.

A Binary Decision Diagram Approach to On-line Testing of Asynchronous Circuits with Dynamic and Static C-elements

The fast growing in complexity of digital VLSI circuits with the advance of deep sub-micron scaling causes occurrence of faults during normal operation of the circuits. These faults cannot be detected by off-line test or Built-In-Self-Test (BIST) techniques. Further, a number of critical faults may require detection at the functional mode during run-time. On-line Testing (OLT) provides a solution to both the problems, and can be implemented using appropriate Design-for-Testability (DFT) techniques. Nowadays, use of asynchronous circuits in semiconductor industry has rapidly increased because of no clock skew problem, low power consumption, average case performances and high degree of modularity. It has been found in the literature of OLT of VLSI circuits that the number of OLT schemes proposed for asynchronous circuits is very few compared to synchronous circuits. The main drawbacks of the existing OLT schemes for asynchronous circuits are protocol dependency, high area overhead and scalability. In this work, we have proposed a partial replication based OLT scheme for asynchronous circuits with dynamic and static C-elements using Binary Decision Diagram (BDD). The proposed scheme works for all circuits irrespective of their design protocols and achieves high fault coverage and comparatively low area overhead. It has been observed that the area overhead is further reduced with increase in values of FD-transitions (Fault Detecting transitions) exclusion. Furthermore, the use of BDD enables the scheme to handle fairly large circuits.

Intrinsically Stretchable Temperature Sensor Based on Organic Thin-Film Transistors

Achieving reliable electrical performance with stretchability and conformability is a key issue for wearable electronics. In this letter, we demonstrate an intrinsically stretchable temperature sensor element based on organic thin-film transistors (OTFTs). The OTFTs were characterized with respect to their temperature and strain dependence, and subsequently evaluated using differential readout circuit schemes. We considered two circuit variants to accommodate OTFTs with nominally positive or negative threshold voltages. Due to the strain suppression afforded by the differential readout, the intrinsically stretchable temperature sensor element achieves an inaccuracy within 1 °C with uniaxial strains from 0-30 %.

A time-driven FPGA-based fast nuclear charge digitization method

Abstract Without the need of high-speed analog-to-digital converters (ADCs), the method of translating the shape of nuclear pulses into a time width for charge measurement provides the possibility of multi-channel system implementation with commercialized discrete components. In this paper, we propose such a circuit scheme based on field programmable gate array (FPGA) to realize nuclear charge digitization. Compared with other charge digitizing methods using discrete components, the proposed scheme has a shorter measurement dead time and high measurement performance. Since some logic units of the FPGA are developed to replace discrete analog devices, only one additional analog amplifier for each channel is required outside of the FPGA, which makes the circuit scheme compact and feasible for the implementation of multi-channel systems. Combining with a positron emission tomography (PET) detector module that consists of LYSO crystals coupled with a SiPM array for 22Na coincidence measurement, the circuit can achieve the energy resolution of 12.3% with a typical measurement dead time of 500 ns. Using a reference detector with 164.7 ps time resolution, the coincidence time resolution of the two detectors is evaluated as 367.1 ps, which means the proposed circuit also has an acceptable time performance for some applications.

A novel locomotive auxiliary converter control strategy with harmonic suppression for avoiding resonance voltage accidents in an electrified railway

In recent years, the AC‐DC‐AC electric locomotives have been wildly applied in electrified railways, deteriorating the current quality of network. Therefore, filters in electrified railways are essential. However, considering the volume and weight of filters, it is inappropriate to install them on locomotives. And resonance accident caused by high‐frequency harmonics is hard to suppress because of the low switching speed of high‐power Si‐based devices. In this article, a novel locomotive auxiliary converter control strategy with harmonic suppression function is proposed to filter harmonic currents injected into the traction supply network. By controlling the auxiliary converter, the strategy could complete the function of rectification and filtering, converting power for auxiliary equipment, filtering the harmonic current, and suppressing resonance accidents with the high‐frequency characteristics of SiC devices. For compensating high‐frequency harmonics, the parameters of main circuit and control scheme are analyzed to ensure a stable system. The feasibility of the scheme is verified by simulation and RT‐LAB hardware‐in‐loop experiment. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

Low-Loss Characteristics of Metal-Foil-Based Passive Components by Surface-Activated Bonding Technologies

Low-loss passive components for RF signals compatible with the on-wafer process are essential for realizing integrated circuits with high-frequency and high-power operations. We successfully fabricate thick-metal-film-based coplanar waveguides (CPWs) and inductors (INDs) by directly bonding a 17- $\mu \text{m}$ -thick Al foil to a sapphire (0001) substrate and wet etching. The surface-activated bonding (SAB) technologies at room temperature are used. RF characteristics of the foil-based passive components are compared with those of components made of 1- $\mu \text{m}$ -thick evaporated Al layers. We obtain a better insertion loss and a higher ${Q}$ -factor for foil-based CPWs and INDs, respectively. The measured characteristics are compared with those obtained by an analysis based on the equivalent circuit scheme. Impacts of side etching of foils and surface oxidation on their characteristics are observed. Characteristics of virtual components made of 1- $\mu \text{m}$ -thick Al foils, i.e., 1- $\mu \text{m}$ -thick Al films with the same resistivity as that of foils, are analytically investigated.

Distinguishing Bulk and Grain Boundary Transport of a Proton-Conducting Electrolyte by Combining Equivalent Circuit Scheme and Distribution of Relaxation Times Analyses

Features of ionic transport across grains and along grain boundaries of solid oxide electrolyte materials play a key role in the efficient application of these materials in electrochemical devices including solid oxide fuel and electrolysis cells, membrane reactors, and electrochemical converters. In the present work, equivalent circuit scheme (ECS) and distribution of relaxation times (DRT) analyses were successfully utilized to distinguish the bulk and grain boundary resistances, both from each other and from the polarization resistance component. Considering a Ag|BCG|Ag symmetrical cell (where BCG = BaCe0.9Gd0.1O3−δ) as a simple model system, the complex impedance spectra were obtained. Due to the close characteristic parameters (relaxation time and capacitance) exhibited by some electrochemical processes, these spectra cannot be precisely resolved using only an ECS tool, although a joint application of ECS and DRT allowed the spectra to be deconvoluted. As a result, data concerning grain and grain bou...

КАЧЕСТВО РАБОЧЕГО ПРОЦЕССА, ЭКСПЛУАТАЦИЯ И РЕСУРСНЫЕ ВОЗМОЖНОСТИ СОВРЕМЕННОГО ВСПОМОГАТЕЛЬНОГО ДИЗЕЛЯ С ЭЛЕКТРОННЫМ УПРАВЛЕНИЕМ

The article focuses on the general characteristics of the new generation electronically controlled marine diesel engine Caterpillar С-9. The principles of operation and composition of the elements involved in the organization of the workflow, monitoring and diagnostics of engine parameters in operation have been listed. There has been presented a schematic circuit of the engine electronic control system, which includes a hydraulic pump to activate the injection process, circulation lubrication pipeline, fuel filter, oil filter, oil cooler, nozzles. The recommended schedule of preventive inspections and repairs of Caterpillar C9 diesel engine has been analyzed; its environmentally friendly characteristics have been evaluated. There was made the comparison of the changes of workflow parameters of Caterpillar C9 diesel engine with S20 Sulzer diesel engine with conventional control under different loads. The results of long-term operation of both diesel engines are given; structural shortcomings associated with the insufficient quality of many component parts are analyzed. High requirements for fuel quality and purification have been mentioned. The engine has no indicating instrumentation, diagnostics of failure of any element or system, as well as its elimination is performed only by a service technician who can enter the database. Practical examples of the repeated failures in the engine computer control system of the tanker “Marine Alliance” and attempts to reveal their sources are specified in the senior engineer’s report. The structural complexity of fuel supply elements and engine workflow control systems along with the dependence of the engine team on the service center lead to difficulties in operation, significant financial costs and reducing engine operational time.

Promoting Representational Fluency Through Dynamically Linked Concrete and Abstract Representations in Electric Circuits

This study investigates the impact of utilizing dynamically linked concrete and abstract representations of objects in modern, virtual electric circuit laboratories on the cognitive evolution and the representational fluency of high school students. The students (N = 27, aged 16–17) were randomly divided into two classes: the first class used a realistic virtual laboratory environment, dynamically linked to a representation of the schematics of each circuit constructed, while the other class used the same virtual environment without the circuit schematics representation affordance. Both classes were given the same inquiry-based instruction and the same instructional material. A pre-/post-instructional assessment scheme was used to evaluate students’ knowledge evolution and skills in reconstructing electric circuits from an either realistic virtual or abstract schematic form to the other. The statistical analysis of the results shows that, after instruction, all students in both groups are capable of understanding thoroughly the operation and transforming simple electric circuits from any given form to the other successfully. Our findings also indicate that the students who used the dynamically linked concrete and abstract representations of electric circuits during teaching seem to outperform the students of the other group, regarding their understanding of the operation and the transformation of more complex electric circuits. Furthermore, the ability to transform electric circuits from one form to another is found to correlate well with students’ conceptual evolution. Potential implications of these findings are being discussed, while a model of the mental model construction process is being proposed.

Estimation of decoherence in electromechanical circuits

This letter presents a schematic circuit with capacitive coupling between the CPW Cavity Center Trace (resonated with electromagnetic mode) and the mechanical Nanoresonator mediated by Transmon, resulting in the Cross-Kerr electromechanical effect. Then we show the dynamics of quantum states, showing the generation of superposition states and bipartite entanglement of continuous variables through nonlinear quantum electrodynamics in the circuit. Finally, we calculated and estimated the parameter for mechanical outcome through phase measurements of the CPW Cavity Center Trace electromagnetic mode.

PARAMETERS OF COEFFICIENTS OF THE RAIL FOUR-POLE OF THE JOIN THE JOINTLESS RAIL CIRCUI TLESS RAIL CIRCUIT ACCORDING T CCORDING TO LOCOMOTIVE RECEIVER

In article questions of a conclusion of the coefficients of the equations of a rail four-polar of a jointless rail circuit are considered, taking into account uncertainty of borders where the travelling receiver which is applied now on a railway transportation is used. Mathematical modeling of four-pole coefficients by locomotive receiver is given. Analytical expressions and coefficients for calculation of the locomotive current flowing under the receiving coils and transfer resistance are derived. The scheme of a jointless rail circuit in the presence of moving units and mutual influence on each other is given. The influence of the carrier information from the traffic light in front, where it is necessary to take into account the factor of the signal level from the outgoing train, so that the information of the neighboring rail circuit would not be perceived, since there are no insulating joints. A scheme with five four poles has been developed and coefficients of these four poles have been obtained to calculate the current of the locomotive flowing under the receiving coils. Analytical expressions are obtained for determining the current for receiving by the receiving coils of a locomotive, the minimum supply voltage of an unbroken rail circuit and the transmission resistance of a rail circuit in normal operation for a locomotive receiver.

Electric circuit of brushless motor electric drive of technological objects of agriculture

In the article schemes of power circuits of a feed of synchronous reluctance machines are considered. The features of the choice of the most rational scheme by the criterion of improved weight and size parameters are shown. It is shown that the specific parameters of electric drives have values that exceed similar synchronous electric drives by approximately 20%. Improvement of specific parameters in the agriculture electric drive can be achieved not only due to the complexity of the electric machine construction, but also due to the choice of optimal schemes of power circuits. So, in agriculture electric drives with individual sources with rectangular current form, the values of overloads corresponding to electric drives with complex (compound) rotor design.

Design and Implementation of a Weapon System Detector for Air-to-ground Missile

Based on the theories of modular design, single-chip microcomputer system and ARINC429 bus communication technology, a feasible design scheme of a detector circuit is put forward. The design we proposed can meet the urgent demand of testing and maintaining new military equipment for the forces. The proposed detector we have designed can meet all the technical requirements of certain air-to-ground missile installed on certain aircraft. The detector is portable and convenient to be operated. The detector can test in-flight fire control system, the launcher and the whole air-to-ground missile system. The design scheme has some reference value to other detectors of air-to-ground missile system.

ELECTRICAL ENERGY MEASURING MODUL WITH GALVANOMAGNETIC CURRENT TRANSDUCER

In our time, electrical energy has been used in all household and industrial settings. This is achieved by the ability of the device to convert it into another form of energy – mechanical, lifting, light, heat, and many more. etc., and vice versa. Exactly this variety of energy converters enables the development of electronics, communications, transport, health, energy, but also the search for and the creation of new sources and converters known as alternative sources of energy.The generation and consumption of electrical energy does not end there. In order to assess the quantity and quality of the generated electrical energy, special devices known as electric meters are needed. Measurement of electrical energy is important for both households and industry, as well as for its production and efficient use. There are different methods and means for electrical energy measurement. They work on the basis of different physical principles – induction, electromagnetic, galvanomagnetic, etc., but the task of all of them is to show the result of the current and voltage integrated in time.Various methods are known for the basic parameters measurement defining the value of electrical energy (electrical current and voltage). With the development of microelectronics, and in particular of sensor technology, various sensor transducers have been developed to measure electrical energy through a high precision electric circuit using a contact and/or contactless method. One of the most commonly used sensor transducers for measurement of electrical current in modern energy meters are magneto-sensitive ICs. They are characterized by high reliability of the output signal, temperature and electrostatic steadiness and not least a long period of trouble-free operation1. The sensible element in magneto-sensitive ICs is most often a Hall element or a magnetoresistor. It measures the current flowing through the conductor by converting the magnetic field around it into electrical voltage. The advantage of magneto-sensitive ICs is possibility in a semiconductor chip to create sensitive element and a processing and forming signal circuit. This makes the measuring channel more secure and compatible with integrated circuits for processing and transmitting measurement data.The article presents an experimental model of an electronic module for electrical energy measurement in a single phase AC current circuit. The measuring module is realized on the basis of a specialized integrated circuit ADE series of the Analog Device Company for electrical energy measurement and a current channel, realized by a magnetic-sensitive integrated circuit ACS of the Allegro MicroSistem Inc. for electrical current measurement. Presented are a block and schematic circuit diagrams, experimental design and experimental results showing the performance of the device.

Mechanically generating entangled photons from the vacuum: A microwave circuit-acoustic resonator analog of the oscillatory Unruh effect

We consider a model for an oscillatory, relativistic accelerating photodetector inside a cavity and show that the entangled photon pair production from the vacuum (Unruh effect) can be accurately described in the steady state by a non-degenerate parametric amplifier (NDPA), with the detector's accelerating center of mass serving as the parametric drive (pump). We propose an Unruh effect analogue NDPA microwave superconducting circuit scheme, where the breathing mode of the coupling capacitance between the cavity and detector provides the mechanical pump. For realizable circuit parameters, the resulting photon production from the vacuum should be detectable.

A novel square wave generator based on the translinear circuit scheme of second generation current controlled current conveyor-CCCII

A robust square wave generator employing a sole capacitor and two resistors has been presented in this study. Low power as well as popular translinear circuit scheme of Second generation current controlled current conveyor-CCCII has been taken as an active element to implement the proposed square wave generator. CCCII inhibits promising features like availability of three mutually independently and electronically adjustable parameters corresponding transconductance (gm), intrinsic resistance (r) of the current input terminal and current gain between two terminals) that are very prevalent for control applications accepted currently. The operating frequency of the proposed model has been analyzed with respect to the passive components present there, with no exposure of output signals to the thermal voltage (VT). Electrical/Device properties (like Noise, Threshold, area etc.) of the proposed circuit have also been discussed in this work. The simulation work was carried out on Synopsis Hspice tool (v-2008.03) from Avant. Satisfying results with anticipation of theoretical and simulated results, including precision (consistency assessment) with Pareto analysis (Ist order Best Test flavored by Decision making analysis) were observed during the study. The 45 nm BSIM CMOS modelling parameters were adopted to prove the theory. The elementary purpose of using such parameters is to maximize the circuit drive and lowering the leakage current. Another purpose of using these modelling parameters is to enhance the realization of the proposed circuit in the form of chip die and further get it fabricated in custom Integrated circuit(IC) form, from a Standard local foundry. Maximum power consumption of the circuit is 600 µW, with ± 1 V rail to rail operating voltages.

Path-Balanced Logic Design to Realize Block Ciphers Resistant to Power and Timing Attacks

In this paper, binary decision diagram (BDD)-based dual-rail precharge logic circuit schemes have been developed to counter differential power analysis attacks, timing attacks, and early propagation attacks. Different precharge logic schemes (top precharging, top-bottom precharging, bottom precharging, and symmetric nMOS bottom precharging) are presented and evaluated. The hallmark of our circuit schemes is that an identical number of switchings is ensured on each circuit path. The transistors are interconnected to create pull-up and pull-down paths to outputs by way of binary decisions based on the input variables, so as to realize the required Boolean function. A simple synthesis algorithm for mapping a given Boolean function to such a BDD-based circuit is also presented. Experimentation has been carried out on two 4-, 16-, 32-, and 64-bits S-boxes to establish resistance of our circuits to power analysis attack and to highlight the low-power characteristics with the help of attributes such as peak power variance, average power, propagation delay, normalized standard deviation of power, and normalized energy deviation. Differential power attacks such as difference of mean and correlation power analysis have been carried out. Resilience to the early propagation effect is also demonstrated.

Circuit-Field Coupling and Magnetic-Thermal Coupling Analysis of RRF Converter Designed With Magnetic Integration

In this paper, the magnetic integration of resonant reset forward (RRF) converter and magnetic-thermal coupling analysis of integrated magnetic (IM) components are explored. The formulas of magnetic reluctance, winding turns, and magnetic flux density are obtained based on the equivalent magnetic circuit and minimum current pulsation scheme. Meanwhile, circuit-field coupling model of RRF converter and magnetic-thermal coupling model of IM components are built with the finite-element analysis (FEA) method. The simulation results illustrate that the core of the integrated RRF converter works in an unsaturated condition, the temperature rise of IM components is about 20 °C, and the integrated RRF converter has almost the same power efficiency as the conventional discrete RRF converter. Furthermore, hardware prototypes are fabricated and tested to verify the simulation accuracy and design validity. The conclusion of this paper will provide a reference for improving magnetic integration efficiency in the future design of RRF converter.