Search Results (22)

The goal of this research is to develop a predictive model that determines how low-frequency Electromagnetic Interference (EMI) affects the leakage current behavior of CMOS transistors. Although developed and validated using NMOS devices, the modeling framework can be extended to PMOS transistors; experimental validation of PMOS devices is planned for future work. The model provides essential physical parameter-based analysis of nanoscale device EMI susceptibility during low-frequency operation. The model demonstrates high accuracy and practicality through experimental verification of test chips built with standard TSMC CMOS technology nodes. The findings highlight that modern CMOS designs must account for low-frequency EMI, which can induce leakage shifts significant enough to impact EMC compliance, functional robustness, and reliability in ultra-low-power and near-threshold applications. The research delivers a practical method for designers to evaluate and reduce EMI-induced leakage in integrated circuits. Full article

Achieving high reliability remains the critical challenge for pulsed power supplies (PPS), whose core components are susceptible to severe degradation and catastrophic failure due to long-term operation under electrical, thermal and magnetic stresses, particularly those associated with high voltage and high current. This reliability challenge fundamentally limits the widespread deployment of PPSs in defense and industrial applications. This article provides a comprehensive and systematic review of the reliability challenges and recent technological progress concerning PPSs, focusing on three hierarchical levels: component, system integration, and extreme operating environments. The review investigates the underlying failure mechanisms, degradation characteristics, and structural optimization of key components, such as energy storage capacitors and power switches. Furthermore, it elaborates on advanced system-level techniques, including novel thermal management topologies, jitter control methods for multi-module synchronization, and electromagnetic interference (EMI) source suppression and coupling path optimization. The primary conclusion is that achieving long-term, high-frequency operation depends on multi-physics field modeling and robust, integrated design approaches at all three levels. In summary, this review outlines important research directions for future advancements and offers technical guidance to help speed up the development of next-generation PPS systems characterized by high power density, frequent repetition, and outstanding reliability. Full article

Transition metal (TM)-doped zinc oxide (ZnO) and zirconium dioxide (ZrO₂) nanocrystals exhibit complex correlations between crystal structure, defect chemistry, vibrational properties, and magnetic behavior that are strongly governed by synthesis route and dopant incorporation mechanisms. This review critically summarizes recent progress on Fe-, Mn-, and Co-doped ZnO and ZrO₂ nanocrystals synthesized by wet chemical, hydrothermal, and microwave-assisted hydrothermal methods, with emphasis on synthesis-driven phase evolution and apparent solubility limits. ZnO and ZrO₂ are treated as complementary host lattices: ZnO is a semiconducting, piezoelectric oxide with narrow solubility limits for most 3d dopants, while ZrO₂ is a dielectric, polymorphic oxide in which transition metal doping may stabilize tetragonal or cubic phases. Structural and microstructural studies using X-ray diffraction, electron microscopy, Raman spectroscopy, and Mössbauer spectroscopy demonstrate that at low dopant concentrations, TM ions may be partially incorporated into the host lattice, giving rise to diluted or defect-mediated magnetic behavior. When solubility limits are exceeded, nanoscopic secondary oxide phases emerge, leading to superparamagnetic, ferrimagnetic, or spin-glass-like responses. Magnetic measurements, including DC magnetization and AC susceptibility, reveal a continuous evolution from paramagnetism in lightly doped samples to dynamic magnetic states characteristic of nanoscale magnetic entities. Vibrational spectroscopy highlights phonon confinement, surface optical phonons, and disorder-activated modes that sensitively reflect nanocrystal size, lattice strain, and defect populations, and often correlate with magnetic dynamics. Rather than classifying these materials as diluted magnetic semiconductors, this review adopts a synthesis-driven and correlation-based framework that links dopant incorporation, local structural disorder, vibrational fingerprints, and magnetic response. By emphasizing multi-technique characterization strategies required to distinguish intrinsic from extrinsic magnetic contributions, this review provides practical guidelines for interpreting magnetism in TM-doped oxide nanocrystals and outlines implications for applications in photocatalysis, sensing, biomedicine, and electromagnetic interference (EMI) shielding. Full article

With the rapid advancement of modern electronic devices and wireless communication systems, electromagnetic pollution has become a prominent issue, prompting the development of high-performance electromagnetic interference (EMI) shielding materials. Although traditional metal shielding materials exhibit excellent conductivity, there are many limitations such as high weight, poor flexibility, susceptibility to corrosion, and high cost. To overcome these challenges, in this study, we design and fabricate core-spun yarns using polyester filaments as the core and an aluminum-foil-wrapped layer as the conductive outer component, and further weave them into three conductive fabrics with different structural parameters. Through systematic investigation of their surface morphology, air permeability, electrical properties, and EMI shielding performance, DT5W27 demonstrates optimal overall performance: electrical conductivity of 2722.64 S·m⁻¹, shielding effectiveness of 37.29 dB, and electromagnetic wave attenuation rate of 99.99%. Specifically, even after 100 bending, twisting cycles, and exposure to solutions with pH values ranging from 3 to 9, the fabric maintains high shielding performance. The fabrication process is facile and low cost, and these composites have good flexibility, outstanding EMI shielding performance, exceptional mechanical durability, and chemical stability. These advantages make them have broad application potential in protective clothing and lightweight shielding materials. Full article

Unmanned Surface Vehicle (USV) offers a cost-effective platform for high-resolution marine magnetic surveys using shipborne fluxgate magnetometers. However, platform-induced magnetic interference and electromagnetic interference (EMI) can degrade data quality, even with paramagnetic hulls. This study evaluates fluxgate magnetometer data acquired from a paramagnetic-hulled USV. Noise characterization identified EMI and maneuver-induced high-frequency noise, the latter of which was effectively reduced through low-pass filtering. We compared four different correction approaches addressing both vessel attitude and magnetization. The results demonstrate that the paramagnetic hull significantly reduces magnetic interference and shortens the duration of viscous magnetization (VM) effects caused by eddy currents in the platform, compared to conventional ferromagnetic vessels. Nonetheless, residual magnetization from onboard ferromagnetic components still requires correction. A method utilizing all nine components of the susceptibility tensor demonstrated improved accuracy and stability. Despite corrections, low-frequency VM-related noise during azimuth changes and a consistent absolute offset (~200 nT) remain when compared to towed scalar magnetometer data. These findings validate the use of paramagnetic USV for vector magnetic surveys, highlighting their benefit in VM mitigation while emphasizing the need for further development in VM correction and offset correction to achieve high-precision measurements. Full article

In this paper, a method of estimating the probability of susceptibility of a component on a circuit board to electromagnetic interference (EMI) is presented. The integrated circuit electromagnetic compatibility (IC EMC) standard IEC 62132-4 enables the assessment of the susceptibility of an IC by determining the forward power incident on each pin required to induce a malfunction. Although we focus on IC susceptibility, the method might be applied to other components and sub-circuits where the same information is known. Building upon a previously established numerical model capable of estimating the average coupled forward power at the end of a trace of a lossless PCB trace for a known load in a reverberant environment, this paper updates the model by incorporating PCB losses and utilizes the updated model to estimate the distribution of coupled forward power at the package pin over a number of boundary conditions in a reverberant field. Thus, the probability of failure can be predicted from the known component susceptibility level, the length, transmission line parameters, and the loading of the track to which it is attached. To validate this numerical model, the paper includes measurements obtained with a custom-designed RF IC detector, created for the purpose of measuring RF power coupled into the package pin via test PCB tracks. Full article

The digital integrated circuit (IC) design industry is continuously evolving. However, the rapid advancements in technology are accompanied by major reliability concerns. Conventional clock-based synchronous designs become exceedingly susceptible to transient errors, caused by radiation rays, power jitters, electromagnetic interferences (EMIs), and/or other noise sources, primarily due to aggressive device and voltage scaling. quasi-delay-insensitive (QDI) asynchronous (clockless) circuits demonstrate inherent robustness against such transient errors, owing to their unique architecture. However, they are not completely immune. This article presents a hardened QDI Sleep Convention Logic (SCL) asynchronous architecture, which can fully recover from radiation-induced single-event effects such as single-event upset (SEU) and single-event latch-up (SEL). Multiple benchmark circuits are designed based on the proposed architecture. The simulation results indicate that the proposed designs offer substantial energy savings per operation, dissipate substantially less power during idle phases, and have lower area footprints in comparison to designs based on an existing resilient Null Convention Logic (NCL) architecture at the cost of increased latency. In addition, a formal verification framework for the proposed architecture is also presented. The performance and scalability of the proposed verification scheme are demonstrated using several multiplier benchmark circuits of varying width. Full article

Operational amplifiers (op-amps) are widely used in circuit systems. The increasing complexity of the power supply network has led to the susceptibility of the power supply port to electromagnetic interference (EMI) in circuit systems. Therefore, it is necessary to investigate the electromagnetic susceptibility (EMS) of op-amps at the power supply port. In this paper, we assessed the effect of EMI on the operational performance of op-amps through the power supply port by a bulk current injection (BCI) method. Firstly, we conducted the continuous sine wave into the power supply port by a current injection probe and measured the change in the offset voltage under EMI. Secondly, we proposed a new method of conducted susceptibility and obtained the susceptibility threshold regularities of the op-amps at the power supply port under the interference of different waveform signals. Our study provided conclusive evidence that EMI reduced the reliability of the op-amp by affecting the offset voltage of op-amps and demonstrated that the sensitivity type of op-amps was peak-sensitive at the power supply port. This study contributed to a deep understanding of the EMS mechanism and guided the design of electromagnetic compatibility (EMC) of op-amps. Full article

Most electronic devices are susceptible to electromagnetic interference (EMI); thus, it is necessary to recognize and identify the cause and effect of EMI as it can corrupt electronic signals and degrade equipment performance. Particularly, in semiconductor manufacturing, the equipment used for image capturing is subject to various noises induced by EMI, causing the image analysis to be unreliable during the image recognition and digitization process. Thus, in this research, we aim to detect and quantify the influence of EMI on semiconductor SEM (scanning electron microscope) images. For this, we apply several useful denoising and edge detection techniques to find a clearer distorted shape from EMI-generated images and then compute five shape-related measures to evaluate the distortion. From a comprehensive experimental analysis and statistical tests, it is found that the medians of all the extracted shape-related measures of high-EMI SEM images are higher than those of both medium- and weak-EMI SEM images, and also all the p-values of the statistical tests are close to 0, and thus we can conclude that all the measures are good quantification metrics for assessing the impact of EMI on semiconductor SEM images. Full article

In this work, a multi-task convolutional neural network with multi-input (MIMT-CNN) is proposed for electromagnetic interference (EMI) signals recognition and electromagnetic environment risk evaluation of the data link of unmanned aerial vehicle (UAV). The visualized performance parameters, short-time Fourier transform (STFT) spectrograms, and constellation diagrams are obtained by experiment on the electromagnetic susceptibility of UAV’s datalink. In particular, the constellation diagram is further enhanced by calculating the density distribution of sampling points to obtain the normalized density constellation. Taking the above different categories of images as the input of the expected model, the multi-element and high correlation EMI features are extracted and fused in the MIMT-CNN. Besides, the structure of series-parallel connection is adopted in the trained model and the Bayesian optimization is also used to select hyperparameters. In this case, the perception model with higher reliability can be obtained. On this basis, the performance and complexity of the obtained model with different input channels are compared. The results show that with the input of constellation diagram, especially the normalized density constellation, can significantly improve the accuracy of the model. Besides the normalized density constellation, the model with visualized performance parameters and STFT spectrogram as inputs has a much better performance. Full article

Electronic equipment is indispensable in the industrial 4.0 era. Electromagnetic Compatibility issues with electronic devices are increasingly concerning. The phenomenon of electromagnetic field compatibility is getting higher and higher. The operating quality of electronic equipment is more and more adversely affected, such as by the phenomenon of hesitation in operation for the operating structures, the generation of fire and explosion of electrical equipment, the loss of information, and many other negative effects. This paper discusses the relationship between Electromagnetic Compatibility (EMC) scoring, Electromagnetic Interference (EMI) scoring, and Electromagnetic Susceptibility (EMS) scoring with the performance quality of electronic devices (QUA). We perform reviews on regulatory institutions governing Electromagnetic Compatibility on electronic devices. To evaluate the proposed Electromagnetic Compatibility structure and its relationship to electronic devices, we proposed to use the Partial Least Squares Structural Equation Modeling (PLS-SEM) method. The research results of the model show that the electronic device layout conditions and the lack of systematic conditions have a negative impact on the operating quality of the electronic equipment, while the conditions on equipment techniques, scientific and technological resources have positive and significant impacts. Full article

A low electromagnetic interference (EMI), precision temperature control system for sensitive piezoelectric sensors stabilization and their thermal characteristics research was proposed. Quartz crystal microbalance (QCM) was chosen as the device to be tested. Recently, QCMs found use in many fields of study such as biology, chemistry, and aerospace. They often operate in harsh environments and are exposed to many external factors including temperature fluctuations, to which QCMs are highly susceptible. Such disturbances can cause undesirable resonant frequency shifts resulting in measurement errors that are difficult to eliminate. The proposed solution enables measurements of QCMs thermal characteristics, effectiveness evaluation of temperature compensation methods, and testing of the frequency stability. As a part of the developed solution, two independent temperature regulators were used: first to maintain the QCM crystal at desired temperature, and second to keep the QCM oscillator circuit at fixed temperature. The single regulator consists of a thermoelectric module (TEC) used for both heating and cooling. Two considered TEC driving methods were compared in terms of EMI and their impact on the QCM signal quality. The proposed system was examined for its temperature stabilization capability showing high stability of 11 mK_p-p for one hour and the setpoint accuracy of ±15 mK in the full temperature range. Full article

Bidimensional nanomaterials, such as graphene, respond to the rising demand for electromagnetic interference (EMI) shielding materials, followed by the advancements in wireless technology and increased signal sensitivity in electronic devices, especially for the safety of aircraft and other structures. Lightweight nanocomposites reinforced with 2D carbonaceous nanofillers can replace metals thanks to their ability to attenuate electromagnetic waves and low susceptibility to corrosion. In this work, the EMI shielding properties in the X band (8–12 GHz) of high content graphene nanoplatelets (GNPs) nanocomposites have been investigated. Both the effect of filler content and the nanoarchitecture have been studied. For this purpose, two different configurations have been considered, compact and porous, varying the filler content (from 10 wt% to 90 wt%) and the thickness of the samples. Specifically, four different systems have been tested: thin (i) and thick (ii) compact laminates and thin (iii) and thick (iv) porous coatings. The morphology of the material significantly influences its electromagnetic response in terms of reflection and absorption capacity. Maximum effective absorption of 80% was found for disordered structures, while a maximum reflection of about 90% was found for system highly aligned structures. Full article

Using a sample coated with three types of carbon-based paints, namely single-wall carbon nanotube (SWCNTs), carbon black, and graphite, the amount of radio wave absorption for each was measured. SWCNTs proved to have the superior radio wave absorption effect in the millimeter band. Considering the change in the amount of radio wave absorption depending on the coating amount, three different coating thicknesses were prepared for each test material. The measurement frequency was set to two frequency bands of 28 GHz and 75 GHz, and the measurement method was carried out based on Japanese Industrial Standard (JIS) R1679 “Radio wave absorption characteristic measurement method in the millimeter wave band of the radio wave absorber.” As for the amount of radio wave absorption in the 28 GHz band, a maximum amount of radio wave absorption of about 6 dB was obtained when 35 m of CNT spray paint was applied. It was confirmed that the carbon black paint came to about 60% that of the SWCNT, and the graphite paint did not obtain much radio wave absorption even when the coating thickness was changed. Furthermore, even in the 75 GHz band, the radio wave absorption was about 7 dB when 16 μm of CNT spray paint was applied, showing the maximum value. Within these experimental results, the CNT spray paint has a higher amount of radio wave absorption in the millimeter wave band than paints using general carbon materials. Its effectiveness could be confirmed even with a very thin coating thickness of 35 μm or less. It was also confirmed that even with the same paint, the radio wave absorption effect changes depending on the difference in coating thickness and the condition of the coated surface. Full article

The Overhauser magnetometer is a scalar quantum magnetometer based on the dynamic nuclear polarization (DNP) effect in the Earth’s magnetic field. Sensitivity is a key technical specification reflecting the ability of instruments to sense small variations of the Earth’s magnetic field and is closely related to the signal-to-noise ratio (SNR) of the free induction decay (FID) signal. In this study, deuterated ¹⁵N TEMPONE radical is used in our sensor to obtain high DNP enhancement. The measured SNR of the FID signal is approximately 63/1, and the transverse relaxation time T₂ is 2.68 s. The direct measurement method with a single instrument and the synchronous measurement method with two instruments are discussed for sensitivity estimation in time and frequency domains under different electromagnetic interference (EMI) environments and different time periods. For the first time, the correlation coefficient of the magnetic field measured by the two instruments is used to judge the degree of the influence of the environmental noise on the sensitivity estimation. The sensitivity evaluation in the field environment is successfully realized without electrical and magnetic shields. The direct measurement method is susceptible to EMI and cannot work in general electromagnetic environments, except it is sufficiently quiet. The synchronous measurement method has an excellent ability to remove most natural and artificial EMIs and can be used under noisy environments. Direct and synchronous experimental results show that the estimated sensitivity of the JOM-4S magnetometer is approximately 0.01 nT in time domain and approximately 0.01 nT/$\sqrt{\mathrm{Hz}}$ in frequency domain at a 3 s cycling time. This study provides a low-cost, simple, and effective sensitivity estimation method, which is especially suitable for developers and users to estimate the performance of the instrument. Full article