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关键词： Class E circuit   parasitic capacitors   soft switching   zero voltage switching (ZVS)  

摘要： This paper explores the diverse applications of Silicon Metal-Oxide-Semiconductor Field-Effect Transistor (Si MOSFET) power switch devices in Class E circuit switching. Class E circuit is known for their exceptional efficiency and adaptability across a wide range of applications. However, the performance of Class E circuit can be significantly affected by parasitic components, particularly parasitic capacitors, which play a crucial role in the operation of the converter. This is because parasitic capacitors in Si MOSFET have the potential to increase switching losses in the power converter circuit by storing and releasing energy during switching transitions and can limit the speed of MOSFET switching. The study has determined that IRF510 combined with the TC 4422 driver achieves an efficiency of 98.21%, making it the most suitable switching device for high-frequency Class E circuit. Therefore, achieving Zero Voltage Switching (ZVS) of a Class E circuit is attainable by carefully selecting the appropriate power switch device and considering the value of parasitic capacitances to mitigate voltage spikes and ringing effects. © 2025, Semarak Ilmu Publishing. All rights reserved.

关键词： Transistors   Nanoscale devices   MOSFET   Semiconductor device measurement   Optical variables measurement   Optical devices   Logic gates   Quantum measurements   COMSOL multiphysics   geometry workaround   indirect band gap overcoming   inter-sub-band transitions (ISBT)   nanophotonic and nanoelectronic silicon devices  

摘要： The fabrication of nanoelectronic and nanophotonic devices based on embedded quantum structures has become feasible over the last decades, and the field is continuously improving. Quantum measurements describing evolving configurations are required as part of the optical characterization and performances study of these devices. To ensure accuracy, it is necessary to determine a reliable evaluation of the expected quantum effects relevant to both stationary and time-dependent measurements. Based on a case study of a quantum well embedded in a nanoelectronic MOSFET device as the gate-recessed channel (GRC), a set of possible quantum measurements that can serve as a basis to similar applications of the rules on additional devices is presented and analyzed.

关键词： MOSFET devices  

摘要： This paper presents a novel deep trench-type SiC MOSFET integrated with Schottky diodes (DT-JMOS) designed to improve oxide reliability and switching performances. In contrast to conventional SiC trench MOSFET with Schottky diodes (CT-JMOS), the DT-JMOS utilizes a narrower JFET region and a P-bot structure, resulting in superior electric field reductions in gate oxide layer to improve reliability. The unique structure also enables double-channel operation and deeper embedded Schottky contacts, significantly enhancing the current conduction capabilities in both the first and third quadrants. Furthermore, simulation results indicate that the DT-JMOS achieves a 97.6 % decrease in gate-to-drain capacitance (Cgd), leading to a 67.5 % improvement in gate-to-drain charge (Qgd), and eventually resulting in reductions by factors of 3.2 and 3.5 for figure of merit Qgd × Ron,sp and total switching losses (Etotal), respectively. These attributes suggest that the DT-JMOS is more suitable for high-voltage and high-frequency applications. © 2025

关键词： Coils   Protection   Bandwidth   Silicon carbide   MOSFET   Frequency measurement   Resonant frequency   Gain   Current measurement   Broadband communication   Drift and droop errors   high bandwidth   medium-voltage (MV) SiC mosfet   overcurrent protection   Rogowski coil  

摘要： To guarantee safe switching of the expensive medium-voltage (MV) device with limited durability, the overcurrent protection scheme based on Rogowski coil current sensor (RCCS) is the promising method, featuring fast response and galvanic isolation. However, it is an inherent contradiction to achieve the RCCS with both high noise immunity and high-bandwidth capabilities. In addition, the nonideal dc and low-frequency characteristics of the integrator cause drift and droop errors. In this article, to address the aforementioned challenges, the broadband RCCS is developed and integrated into the overcurrent protection circuit for the MV SiC mosfet. The novel coil is designed based on the transmission line theory to overcome the constraints imposed by parasitic components on bandwidth. The proposed coil achieves an extra-high bandwidth of approximate 300 MHz with high mutual inductance and shielding layers for high noise immunity. Furthermore, the broadband integrator design method with low-frequency attenuation is proposed to eliminate drift and reduce droop errors significantly. Based on the developed RCCS, the proposed overcurrent protection circuit reacts to both the fault under load and hard switching fault rapidly and softly turns off the device within merely 200 ns. Comprehensive experiments demonstrate its exceptional potential in monitoring current and protecting the expensive MV devices.

关键词： Power MOSFET  

摘要： The parallelling of power semiconductor devices is essential for desired current ratings and the system is prone to the current unbalancing due to parameter variations. SiC devices with significant variable threshold voltage due to manufacturing yield and temperature distribution have a consequential possibility of dynamic current unbalancing. This paper presents the peak detection-based current balancing of parallel-connected SiC devices to minimize the turn-on and turn-off current unbalancing. PCB current sensors are used for the measurement and feedback of the signal for this peak detection-based current balancing mechanism. © 2025

关键词： Logic gates   Inductance   Threshold voltage   MOSFET   Silicon carbide   Resistance   Aging   Transient analysis   Switches   Stress   Asymmetric layout   current sharing   parallel connection   silicon carbide (SiC) metal oxide semiconductor field effect transistors (MOSFETs)   stray inductance   threshold voltage  

摘要： For high-capacity applications, paralleling multiple silicon carbide (SiC) metal oxide semiconductor field effect transistors (mosfets) is essential. However, it is challenging to achieve complete symmetry in the gate circuits of parallel devices, resulting in mismatched gate inductances, which may lead to the current imbalance. This article focuses on investigating the evolution of threshold voltage dispersity under mismatched gate inductances and its impact on the current sharing evolution. It is found that mismatched gate inductances cause the threshold voltage dispersity to increase with gate stress time, thereby inducing a deterioration in current sharing. A boost converter with two devices in parallel was tested, demonstrating that the difference in the minimum turn-off gate voltage including undershoot is the primary trigger for increased threshold voltage dispersity. Besides, an off-state gate voltage optimization strategy was proposed to effectively mitigate the increase in threshold voltage dispersity and improve the evolution of current sharing under mismatched gate loop inductances. The findings are intended to improve the performance of SiC mosfets in parallel applications.

关键词： Strain measurement  

摘要： Evaluating the mechanical performance and operational conditions of bridge structures relies on accurately measuringement of vibration displacement. Such measurement can provide essential parameters, such as mode and frequency, to assess the operational status and condition of damaged bridge structures. However, traditional displacement monitoring techniques have high cost, low accuracyare expensive, have low accuracy, and offer and limited measurement positions. This paper proposes a A low-cost, non-contact, and multi-point measurement method was proposed in this paper,based on the Kernelized correlation filters (KCF) algorithm to measure the vibration displacement of bridges. The proposed method used shaking Shaking table tests on a dual-column pier model were conducted,with energy dissipation links under different white noise sweeps. The recorded vibration displacement from a laser displacement sensor (LDS) was used as a reference for comparison. The natural frequencies and mode shapes of the dual-column pier and bridges were identified using the covariance-driven stochastic subspace identification method. The study verified the The reliability, feasibility, and accuracy of machine vision technology in identifying the natural frequencies and mode shapes of bridges were verified. The results showed that the small amplitude vibration displacement of the dual-column pier identified by the KCF algorithm is almost consistent with the waveforms, change trends, and peak values recorded by LDS, with a maximum peak error of 4%. The error between the natural frequencies identified by the KCF algorithm and the LDS results was within 2.5%. The confidence level of the mode shapes identified between both approaches was above 0.90. © 2025 Chinese Vibration Engineering Society. All rights reserved.

关键词： 功率控制   线性化   大动态   PID   定向耦合器  

摘要： 在电子对抗系统中,随着对抗领域的拓展和系统功能的提高,对发射机功率输出精准性的提高已得到越来越多的重视。在不同的功率控制方案中,数字闭环功率控制具有大动态、高精度、脉冲适应能力强、功率自动校准、不需要外部控制信号、具有自适应功能等优点。设计了一种数字闭环功率方案,通过实验验证,对0.35~2 GHz频段功放的输出功率控制精度可达到0.3 dB(r.m.s.),动态范围可达45 dB。

关键词： MOSFET-type gas sensor   Zinc indium tin oxide (ZITO)   Co-sputtering   X-ray photoelectron spectroscopy (XPS)  

摘要： The growing demand for high-sensitivity and low-power gas sensors has driven the exploration of advanced sensing materials. In this study, we fabricated MOSFET-type gas sensors using co-sputtered zinc indium tin oxide (ZITO) films as sensing layers, with five different films containing varying ratios of indium tin oxide (ITO) and ZnO mixtures. As the Zn content increased, the agglomeration sizes within the films decreased, exhibiting amorphous-like morphology. X-ray photoelectron spectroscopy (XPS) revealed that scarce Zn content induced oxygen vacancies, while the number of hydroxy groups increased with higher Zn content. These material properties of the sensing layers significantly influenced the gas sensing characteristics. At high temperatures (similar to 210 degrees C), the oxygen vacancy-rich sensor showed the highest gas response, whereas the hydroxy-rich sensor exhibited enhanced performance at low temperatures (similar to 150 degrees C). The adjustment of the co-sputtering ratio influences gas response, power consumption, and response time, allowing for the fabrication of sensors optimized for specific applications by comprehensively considering various performance factors. We believe that this method can be applied to the formation of a wide range of sensing materials.