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关键词： Inductance   Multichip modules   Layout   Silicon carbide   MOSFET   Vehicle dynamics   Switches   Wires   Couplings   Silicon   Current sharing   multichip silicon carbide (SiC) power modules   symmetric layout  

摘要： This article introduces a fully symmetric layout fora 4-parallel silicon carbide (SiC)MOSFEThalf-bridge power mod-ule, wherein each power loop within the module exhibits physicaland electrical symmetry along thex-axis,y-axis, and center. Thissymmetric layout ensures inductance consistency across the powerloops, facilitating balanced current sharing within the power mod-ule. The imbalance ratio of inductance across the parallel loops inthe proposed module is less than 2%. Further reduction in parasiticinductance is achieved by staggering the power terminals based onthe symmetric layout. The optimized power module was fabricatedand subjected to static and switching tests, demonstrating balancedcurrent and thermal distribution. In addition, the parasitic induc-tance of the proposed power module, calculated based on the doublepulse test results, is found to be 3.54 nH, significantly lower thanthat of commercially available modules of the same rating

关键词： Pulse transformers   Tumors   Voltage   MOSFET   Inductance   Topology   Generators   Damping   Windings   High frequency   Drive circuit   high-frequency bipolar pulses (HFBPs)   irreversible electroporation (IRE)   magnetic isolated   pulse transformer   undershoot  

摘要： High-frequency irreversible electroporation (H-FIRE), which employs high-frequency bipolar pulses (HFBPs) with high voltage has been successfully used for tumor ablation with the inhibition of muscle contraction. This article designs an undershoot damping circuit with magnetic isolation drive embedded (MI-UD) in main topology of step-up transformers to reduce the undershoot voltage resulting from the energy release of excitation inductance and improve the pulse frequency when outputting HFBPs. The proposed main circuit topology could generate HFBPs with one magnetic core, and no additional magnetic core reset circuit is needed for the excitation inductance. Moreover, the designed drive circuit only needs two control signals with delayed turn-off, including the controls of the MI-UD circuit. Theoretical analysis, simulation, and experimental test indicate that three modules of step-up pulse transformer could output HFBPs. The pulse amplitude could reach +/- 3 kV with the voltage gain of 11.1 (ratio of 1:4, three modules) and dc supply of 270 V. The pulsewidth ranges from 300 ns to 2 mu s. A total energized time of 100 mu s within the burst can be achieved to meet the H-FIRE treatment. The maximum frequency is 400 kHz within the burst. The undershoot at 2 mu s and +/- 3 kV is only 3.3%.

关键词： Degradation   Thermal degradation   Junctions   Impedance   Temperature measurement   Logic gates   MOSFET   Loss measurement   Voltage measurement   Thermal analysis   Condition monitoring   degradation   fault location   power semiconductor devices   silicon carbide (SiC) devices   thermal impedance  

摘要： In this article, we propose a unique and simple method that diagnoses multiple aging effects in power electronic devices minimally invasively and without the necessity of expensive sensors. Different degradation modes, e.g., fatigue of solder and thermal-interface layers, influence the phase of the thermal impedance frequency response function angle Z(--th)(j omega) at specific bandwidths. Thus, tracking changes of the thermal impedance's phase, i.e., the phase shift between periodic device-loss excitation at specific frequencies and the resulting junction temperature response allows identifying these degradation modes. This is exploited by the proposed method for degradation diagnosis, which takes advantage of the temperature dependency of the drain-source voltage. The method excites periodic conduction losses at selected frequencies via small-signal manipulation of the gate-source voltage and measures the phase delay between gate-source and drain-source voltage. The measurable phase delay results partially from the dynamic response of the thermal impedance, because the phase-delayed junction temperature impacts the on -state resistance and therefore the drain-source voltage. Consequently, changes of the measurable phase delay allow identifying changes of angle Z(--th)(j omega) and thus diagnosing the above mentioned degradation modes. This article features a detailed analysis of the proposed method using a general sensitivity analysis. A detailed analysis shows that the discussed method is applicable for silicon (Si) mosfet s, gallium nitride (GaN) high-electron-mobility transistor (HEMTs) as well as silicon carbide (SiC) mosfet s. Experiments with SiC mosfet s, being the most emerging technology in industry, demonstrate that the implemented method can effectively diagnose changes of the thermal path between the device and the heat sink that result from different degradation modes.

关键词： SiC MOSFET   Modelling   Physical effects   Power electronic  

摘要： An improved semi-physical model for a SiC MOSFET incorporated with relevant physical effects and temperature characteristics is proposed based on the EKV model. A simulation analysis of the Junction Field Effect Transistor (JFET) effect, Drain Induced Barrier Lowering (DIBL) effect, channel length modulation effect, velocity saturation effect, and interface trap charge effect in SiC MOSFET devices is performed using Sentaurus TCAD. Based on the influence of physical effects on the characteristics of SiC MOSFET devices, mathematical corrections r(V-gs) and r(V-ds), which can describe the relevant physical effects, are introduced into the original EKV model. The capacitance is accurately modelled to achieve the required match between the transient characteristics of the devices. The accuracy of the model is verified by static tests and double-pulse experiments. Results show that the improved model can do a better job of simulating the actual operating conditions of the device. In addition, its accuracy and applicability are greatly improved, providing a semi-physical model with a wider range of applicability for the simulation of SiC MOSFETs in power electronic systems.

关键词： Electronic dummy load   Power supply test   Lithium-ion   Lithium-polymer   Batteries   state of charge   SoH   MOSFET   Linear/ohmic mode   STM32 microcontroller   Wi-Fi   ESP-01   NodeMCU   ESP32   Low-cost equipment  

摘要： Electronic dummy loads (EDLs) are essential for characterizing the discharge behavior of batteries and power supplies. Accurate battery performance monitoring is critical for applications ranging from renewable energy storage to electric vehicles. This study presents the design and implementation of an advanced, low-cost EDL integrated with Internet of Things (IoT) capabilities using Espressif Systems Platform (ESP) -based microcontrollers, specifically the NodeMCU or ESP32. The primary objective is to monitor lithium-ion battery packages' state of charge (SoC) and state of health (SoH). The designed system maintains a constant current during discharge, ensuring precise capacity measurement despite the decreasing voltage levels of batteries. This feature is essential for accurately determining the battery's capacity and health status. The integration with IoT networks significantly enhances the functionality of the device. Using the ESP-based microcontroller, real-time voltage, current, and power data is transmitted to an online platform, allowing for remote monitoring and data logging. This capability not only improves the accessibility and usability of the system but also facilitates long-term data analysis and performance tracking. The developed dummy load system is versatile, supporting both single-cell batteries and multiple-cell configurations. The adjustable current selection property allows it to draw a constant current from batteries, making it suitable for various applications. Simulation and real-world application results demonstrate the system's effectiveness, providing reliable SoC and SoH information. Our results underscore the potential of integrating IoT technologies with battery monitoring systems, offering enhanced monitoring, improved accuracy, and the convenience of remote access. This innovative, cost-effective approach can significantly contribute to developing more intelligent and reliable battery-powered systems.

关键词： Gamma rays  

摘要： This paper study impact of gamma-ray irradiation on the characteristics of silicon carbide power metal oxide semiconductor field effect transistor (SiC MOSFET) from CREE, Inc., and its corresponding effects on the operation of 5/12 V DC-DC boost converter. The proposed 10 A (C2M0280120D) SiC MOSFET was irradiated by gamma-ray irradiation with a dose rate of 0.99 kGy/h ranging from 0 to 6 kGy. The performance of the circuit in terms of the output voltage, power, as well the converter efficiency was studied before and after SiC MOSFET being irradiated. It was observed after 2kGy the proposed boost converter circuit unaffected by gamma-ray radiation. Therefore, at 2 kGy, the 5/12 VDC boost converter output voltage, power, as well the converter efficiency increases by 17.64 %, 38.42 %, and 22.25 %, respectively from their initial values before irradiation. These increases were believed to be due to the decreases in the threshold voltage, on-state resistance, input, output and reverse transfer-capacitances, as well figure of merit and total gate charge of the SiC MOSFET which were caused by the defects introduced inside the semiconductor during the irradiation and also decreasing of switching times and conduction losses of SiC MOSFET after being irradiated. Finally, the converter circuit stability was increased, whenever the circuit switch exposed to gamma doses up to 2 kGy. Where, during the range of selected gamma doses, the value of energy factor variation was always lower than the energy factor, which means that the proposed converter is stable. © 2025 The Author(s)

关键词： TFET-MOSFET hybrid SRAM   Forward p-i-n current   Static power consumption   Multiplexing strategy   Read/write speed  

摘要： Due to the limitation of MOSFET subthreshold swing, traditional MOSFET-based static random-access memory (SRAM) circuits are difficult to meet the design requirements of low-power integrated circuits. To address these issues, we proposed a half-select disturb-free 12T TFET-MOSFET hybrid SRAM bitcell. It can avoid the forward pi-n current and effectively mitigate the effect of current degradation, which greatly reduces the static power consumption of the circuit and improves the performance of SRAM. Specifically, compared to 12T, the write delay of the hybrid bitcell decreased by approximately 13.994 % at 0.6 V. Meanwhile, a TFET-MOSFET hybrid 8T SRAM array is proposed by a multiplexing strategy to reduce the area consumption. The proposed 4 x 4 hybrid SRAM array is comparable to the 12T bitcell in terms of static noise margin (SNM), read/write speed, and static power consumption. These results indicate that the proposed TFET-MOSFET hybrid 8T SRAM array is a good choice for applications that require low power consumption and high stability.

关键词： MOSFET   Stability criteria   Circuit stability   Noise   Current measurement   Voltage   Thermal stability   Resistors   Force measurement   Standards  

摘要： In the joule balance method to realize the kilogram, a programmable current source (CS) is necessary to produce a stable electromagnetic force to balance the Earth’s gravitational force on the mass. The stability and noise level of the current strongly determine the statistical uncertainty introduced by the force measurement phase in the joule balance. An approach to implement a CS with high stability and low noise by a method of two-stage current parallel summation is presented here, with which the CS can be coarsely and finely tuned separately by two subsystems. Based on this idea, a programmable CS with high stability and low noise has been developed. The output current range is from 0 to 14 mA with a resolution of 3.5 nA. The experimental results show that the stability of the current is better than 0.15 ( $\mu $ A/A)/h at 5 mA, which meets the requirement of the joule balance.

关键词： high frequency   memristor emulator   pinched hysteresis loop   floating   MOSFET  

摘要： This paper presents a novel passive floating memristor emulator that operates without an external DC bias, leveraging the DTMOS technique. The design comprises only four MOSFETs and eliminates the need for external capacitors. The emulator achieves a high operating frequency of around 250 MHz and consumes zero static power. A comprehensive analysis and simulation, conducted using 180 nm CMOS technology, validates the circuit’s performance. The versatility and effectiveness of the proposed emulator are demonstrated through its application in various circuits, including logic gates, a ring oscillator, and analog filters, highlighting its potential for diverse low-power, high-frequency applications. The proposed emulator provides a compact, efficient, and integrable solution for nanoelectronic circuit designs.

关键词： electromagnetic interference   loss measurement   MOSFET   power semiconductor devices   semiconductor device measurement   semiconductor device packaging   semiconductor device reliability   semiconductor device testing   silicon compounds   switching transients  

摘要： Switching transient processes of silicon carbide (SiC) devices induce several challenges, such as voltage and current overshoots, switching losses, d ⁢ v / d ⁢ t $dv/dt$ , d ⁢ i / d ⁢ t $di/dt$ , and electromagnetic interference (EMI), threatening the safe and efficient operation of power electronic systems. Characterization of SiC modules is crucial to address these issues. This paper characterizes the dynamic and EMI performance of a state-of-the-art 1.2 kV / 100 A $1.2 \text{ kV} / 100 \text{ A}$ all-SiC module with the Easy-2B package from Fuji Electric. Using a double pulse test (DPT) platform, the dynamic characteristics are assessed across varying load conditions and gate resistances. Additionally, EMI characteristics of the module are evaluated in a semi-anechoic chamber. Results indicate significant impacts of gate drive parameters and load conditions on switching dynamic and EMI characteristics. These influences are further analyzed based on experimental results and theoretical analysis of the switching transient processes. Finally, the study identifies factors limiting switching speed improvements in SiC modules, including voltage and current overshoots, gate voltage oscillations, and EMI, offering valuable insights for improving device performance.