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关键词： MOSFET   Logic gates   Inductors   Threshold voltage   Circuits   Transformers   Zero voltage switching   DC transformer   DCX   high efficiency   high frequency   high power density   LLC   resonant gate driver (RGD)  

摘要： The LLC dc transformer (LLC-DCX), due to its soft-switching characteristics, achieves high-efficiency energy transfer at high frequencies and is extensively used in high power density applications. However, the drive loss of conventional drive integrated circuits (ICs) is proportional to the switching frequency, leading to disproportionately high gate drive loss at higher frequencies, thereby limiting further increases in the LLC-DCX switching frequency. In this article, a dual channel push pull clamped-interlock resonant gate driver (DPCRGD) is introduced for driving the secondary-side metal-oxide -semiconductor field effect transistor (MOSFETs) of LLC-DCX. The proposed DPCRGD provides two complementary driving signals for LLC-DCX. Compared to conventional voltage source drivers and existing research, the RGD presented here demonstrates lower drive loss and a smaller footprint. This article details the operational principles, loss analysis, parameter optimization design, and comparative studies of the DPCRGD. Ultimately, a prototype operating at 1.3 MHz with an output power of 48 V-6V/30 A was developed. Experimental results validate the effectiveness of the proposed DPCRGD, showing a reduction of gate drive power loss by nearly 88% and a 49% decrease in footprint compared to conventional voltage source driving circuits.

关键词： MOSFET   Capacitance   Logic gates   Gate drivers   Harmonic analysis   Windings   Transformers   Power system measurements   Inductance   Density measurement   DC transformer (DCX)   resonant gate driver (RGD)   synchronous rectification (SR)  

摘要： The drive losses of synchronous rectifier (SR) mosfets become significant factor limiting the efficiency of high-frequency, low-voltage, and high-current output LLC dc transformer (LLC DCX) in data center power supply applications. The resonant gate driver (RGD) can reduce drive losses, but both semiconductor devices and external power supply are required in the current RGDs, which results in more losses and footprint. An all-passive resonant gate driver (APRGD) is proposed in this letter, which consists only passive components, including inductances, capacitances, and transformer windings. The operation principle and parameter optimization method of the proposed APRGD are illustrated in detail, which is then verified by experiments. The peak efficiency of the prototype is improved by 0.83% after using APRGD, and SR drive losses are reduced by 93.4%. In addition, the footprint of APRGD is similar to that of conventional drive ICs. The proposed APRGD has advantages in efficiency and power density compared to current RGDs.

关键词： Least squares approximations  

摘要： Cardiovascular diseases are the world’s leading cause of death;therefore cardiac health of the human heart has been a fascinating topic for decades. The electrocardiogram (ECG) signal is a comprehensive non-invasive method for determining cardiac health. Various health practitioners use the ECG signal to ascertain critical information about the human heart. In this article, swarm intelligence approaches are used in the biomedical signal processing sector to enhance adaptive hybrid filters and empirical wavelet transforms (EWTs). At first, the white Gaussian noise is added to the input ECG signal and then applied to the EWT. The ECG signals are denoised by the proposed adaptive hybrid filter. The honey badge optimization (HBO) algorithm is utilized to optimize the EWT window function and adaptive hybrid filter weight parameters. The proposed approach is simulated by MATLAB 2018a using the MIT-BIH dataset with white Gaussian, electromyogram and electrode motion artifact noises. A comparison of the HBO approach with recursive least square-based adaptive filter, multichannel least means square, and discrete wavelet transform methods has been done in order to show the efficiency of the proposed adaptive hybrid filter. The experimental results show that the HBO approach supported by EWT and adaptive hybrid filter can be employed efficiently for cardiovascular signal denoising. © Shanghai Jiao Tong University 2023.

关键词： Voltage   MOSFET   Silicon carbide   Transformers   High-voltage techniques   Modulation   Capacitors   Asymmetric bipolar pulse   high repetition rate   solid state pulsed power modulator (PPM)  

摘要： This article proposes a solid-state pulsed power modulator (PPM) with asymmetric bipolar pulses and high repetition rates for semiconductor manufacturing processes. Since the proposed PPM is based on high voltage solid-state switches (HVSSes) consisting of series connected silicon carbide (SiC) metal-oxide silicon field effect transistors (MOSFETs), it is simple to obtain variable asymmetric bipolar pulses as well as unipolar pulses. To solve the voltage unbalance problem, which is a critical challenge when the SiC MOSFETs are connected in series, a simple voltage balancing circuit is proposed. This balancing circuit shows superior features such as low loss and high reliability because it is composed of only passive components such as transformers and capacitors. In addition, the proposed PPM can achieve the high repetition rate since the soft switching of all SiC MOSFETs can be accomplished by the balancing transformer. Furthermore, the soft switching characteristic and the low loss of balancing circuit can contribute to the miniaturization of PPM by reducing the sizes of components and cooling systems. The design and implementation of 5 kV PPM with high repetition rate of 500 kHz are presented. Experiment results from the developed PPM are shown to verify the proposed works.

关键词： Batteries   Topology   MOSFET   Circuit breakers   Microgrids   Switching frequency   Switching circuits   Insulated gate bipolar transistors   Switching loss   Battery energy storage system   Cell balancing   dc microgrid   dynamically reconfigurable battery (DRB) technology   low loss  

摘要： Dynamically reconfigurable battery (DRB) technology can effectively address the imbalance problem in traditional energy storage systems. However, the additional switches required for each battery in this technology can introduce significant losses. To further reduce this portion of the losses, this letter proposes a DRB topology suitable for dc microgrid applications. This topology uses the same number of switches as the half-bridge topology but reduces the number of switches that current flows through during operation. Moreover, it allows for hybrid series-parallel connections between batteries, whereas the half-bridge topology only permits series connections. Comparative analysis shows that the proposed topology reduces losses from the additional switches by approximately 33% compared with the half-bridge topology in applications of a similar scale. Simulation and experimental results validate the performance of this topology in controllable input/output and self-balancing. Compared to existing topologies, this solution reduces losses while maintaining reconfiguration capability, making it well-suited for scenarios where high reliability and efficiency are critical. This advancement in DRB technology offers a new approach to energy storage system topology selection.

关键词： Light emitting diodes   Lighting   Wireless communication   MOSFET   Inverters   Mathematical models   Rectifiers   Capacitors   Timing   RLC circuits   Constant current (CC)   dual-customization   special rectifier   wireless power transfer (WPT)  

摘要： Due to the advantages of safety and convenience, wireless power transfer technology is a good candidate for underwater LEDs driving. A wireless LED driver with a single constant current (CC) output value cannot enable LEDs to achieve brightness variation. This letter proposes a reconfigurable rectifier based communication-free wireless LED driver with dual-customization CC outputs. By simply controlling the special rectifier on the receiver, the proposed driver can be selectively configured into two LCC-S-S three-coil structures with different specifications, allowing LEDs to work in energy-saving mode and lighting mode, respectively. In addition, the control unit for mode switching is located at the receiver, making the system communication-free and ideal for underwater LEDs driving. An experimental prototype with dual-customization CC outputs of 0.6 A for energy-saving mode and 1 A for lighting mode is fabricated to verify the feasibility of the proposed wireless LED driver.

关键词： Cylindrical MOSFET   SOISB MOSFET   Analog/RF parameters   Silvco TCAD and multi-gate MOSFET  

摘要： In the current scenario of semiconductor technologies, the researchers are investigating the cylindrical Silicon- on-Insulator Schottky Barrier (SOISB) Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) due to its enhanced analog/RF parameters, high I ON /I OFF ratio and reduced ambipolarity. This study presents an analytical model for the cylindrical SOISB MOSFET, specifically focusing on how to calculate surface potential, threshold voltage, and drain current. Further, the research explores how altering the radius of the concentric SiO2 insulator pillar impacts the MOSFETs performance in analog/RF circuit applications. The Silvaco 3D device simulator has been used for conducting the numerical simulations for a channel length of 22 nm and a silicon radius of 5 nm. The SiO2 insulator pillar radius has been varied from 1 nm to 4 nm and its effect on the device characteristics has been investigated. The results show improved changes in analog/RF parameters and linearity, providing valuable insights for advanced semiconductor technologies.

关键词： Heterojunctions  

摘要： —A novel SiC power MOSFET structure with Source-side Poly-Si/SiC Heterojunctions (SH-MOS) is proposed by introducing Poly-Si regions of the device's source side. Introducing a P + Poly-Si region at the center of the device helps discharge holes, thereby reducing the accumulation of holes beneath the gate oxide layer caused by heavy ion impacts and improving resistance to single-event gate rupture (SEGR). Besides, The P + Poly-Si and N SiC form a p/n type Poly-Si/SiC heterojunction diode (HJD), effectively improving the device's reverse conduction and recovery performance. In addition, introducing a N + Poly-Si region to replace original N + SiC source region on the source side. Due to the different energy bands of the n/p type Poly-Si/SiC heterojunction, the hole current of parasitic BJT’ emitter increases during the single event irradiation process of SH-MOS. This results in a significant decrease in the current gain of the parasitic BJT, thereby improving its Single Event Burnout (SEB) performance. Simulation results show that under the same irradiation conditions, SH-MOS exhibits superior SEGR and SEB resistance compared to Con-MOS. The SEB threshold voltage of SH-MOS is 660 V, which is 214.29 % higher than the 210 V of the original N + SiC source region MOSFET. In addition, the novel SH-MOS structure reduces VF by 45.36 % and reverse recovery charge (Qrr) by 33.32 % compared to Con-MOS, without causing any significant degradation in forward conduction or blocking characteristics. © 2024 Elsevier Ltd

关键词： Void fraction  

摘要： In automotive electronic water pumps, MOSFET is used as power conversion devices to drive water pump motors, however, the high temperature of the engine will cause the electronic water pump MOSFET to overheat and fail. In order to effectively reduce the overheating failure of MOSFET, a thermal simulation model of printed circuit board MOSFET for automotive electronic water pump controllers was established using FLUENT software. The temperature rise characteristics of MOSFET with different void rates under single and multi-void SMT states were analyzed. The analysis results indicate that the thermal resistance of MOSFET in printed circuit boards increases with the increase of void fraction, and the simulation results are verified through experiments, which are consistent with the simulation results. At the same time, when the void ratio is greater than 10 %, the heat dissipation effect of a single void is more pronounced than that of a void. The thermal analysis of printed circuit board MOSFET provides support for effectively controlling MOSFET temperature rise and reducing MOSFET thermal failure. © 2024 The Author(s)

关键词： Compact model   Parameter extraction   Deep learning (DL)   BSIM-CMG   MOSFET  

摘要： An enhanced deep learning (DL)-based parameter extraction method for transistor compact models, named GatedNN, is introduced. GatedNN achieves significant accuracy improvements over existing DL-based parameter extraction techniques. The innovation lies in incorporating neural network (NN) with gating mechanism and compact model-aware techniques: model parameter importance analysis and model quality check. The GatedNN uses gates to resolve optimization conflicts among model parameters by controlling gradient descent during training. The importance analysis focuses on optimizing more crucial parameters that contribute to the current curve. The model quality check cleans the training data fed to the GatedNN and ensures the robustness of the NN output. Evaluated on the BSIM-CMG model with measured FinFET data, the proposed approach demonstrates a substantial 69% error reduction compared to recently DL-based parameter extractor. Furthermore, the scalability and mathematical robustness of the generated model are tested. The proposed GatedNN also provides insights into model parameters and device characteristics, aiding in understanding and adjusting for desired characteristics. We believe the developed method can advance the development of DL-based parameter extraction.