Search

Summary: In this article, we investigated a new structure of a protective meander line (ML): a meander microstrip line (MSL) with two passive conductors. The existing theory of ultra‐short pulse (USP) attenuation in MLs is presented for the first time. Based on this theory, we determined the number of decomposed pulses at the output of the MSL line with two passive conductors, and, for the first time, formulated the conditions for pulse decomposition in the line. The folding of the MSL line into non‐core turns was studied in detail. As a result of this article, we proposed a new theory that involves the utilization of additional groups of decomposed pulses for enhanced USP attenuation. These additional groups were thoroughly examined, and the delays of pulses from these groups were defined. This analysis allowed identifying the reason for their appearance. It was revealed that folding the ML into non‐core turns allows further attenuation of the USP amplitude, which increases with the increase of the number of non‐core turns. To validate the obtained simulation results, we performed experimental measurements and obtained good consistency of the results. The N‐norms analysis demonstrated that the combined use of such folding and passive conductors reduces the probability of electrical breakdown, arc discharge, and dielectric breakdown. The maximum USP attenuation at the output was 24.9 dB. As a result of useful signal integrity analysis, it is proposed to use a folded MSL together with a USB 2.0 "Full‐speed" interface with a data transfer rate of 12 Mbit/s. In addition, it is proposed to use such MSLs in DC power circuits. [ABSTRACT FROM AUTHOR]

Reference placement is promising to handle the increasing complexity in printed circuit board (PCB) designs, which aims to find the isomorphism of the placed template in component combination to reuse the placement. In this paper, we convert the netlist information into a graph and then model the reference placement as a subgraph matching problem. Since the state-of-the-art subgraph matching methods usually recursively search the solutions and suffer from high time and memory consumption in large-scale designs, we develop a novel subgraph matching algorithm D2BS with diversity tolerance and improved backtracking to guarantee matching quality and efficiency. The D2BS algorithm is founded on a data structure called the candidate space (CS) structure. We build and filter the candidate set for each query node according to our designed features to construct the CS structure. During the CS optimization process, a graph diversity tolerance strategy is adopted to achieve efficient inexact matching. Then, hierarchical matching is developed to search the template embeddings in the CS structure guided by branch backtracking and matched-node snatching strategies. Based on the industrial PCB designs, experimental results show that D2BS outperforms the state-of-the-art subgraph matching method in matching accuracy and running time. [ABSTRACT FROM AUTHOR]

Recycling electronic waste (WEEE) is a fundamental aspect of the circular economy. To develop technology and assess its economic aspects, the composition characterization of the waste items is crucial. Neutron-based analytical techniques, such as the INAA, in-beam NAA, and PGAA, are applicable to measure the elemental composition of WEEE. These techniques are bulk representative and offer simultaneous determination of the relevant elements without sample dissolution. This study explores the suitability of neutron-based elemental analysis methods for measuring common WEEE items, e.g., printed circuit boards and integrated circuits. Matrix effects mostly related to the thermal neutron self-shielding, were identified and successfully corrected, ensuring accurate mass fraction measurements. [ABSTRACT FROM AUTHOR]

In response to the challenges of small-size defects and low recognition rates in Printed Circuit Boards (PCBs), as well as the need for lightweight detection models that can be embedded in portable devices, this paper proposes an improved defect detection method based on a lightweight shared convolutional head using YOLOv8n. Firstly, the Spatial and Channel reconstruction Convolution (SCConv) is embedded into the Cross Stage Partial with Convolutional Layer Fusion (C2f) structure of the backbone network, which reduces redundant computations and enhances the model's learning capacity. Secondly, an adaptive feature selection module is integrated to improve the network's ability to recognize small targets. Subsequently, a Shared Lightweight Convolutional Detection (SLCD) Head replaces the original Decoupled Head, reducing the model's computational complexity while increasing detection accuracy. Finally, the Weighted Intersection over Union (WIoU) loss function is introduced to provide more precise evaluation results and improve generalization capability. Comparative experiments conducted on a public PCB dataset demonstrate that the improved algorithm achieves a mean Average Precision (mAP) of 98.6% and an accuracy of 99.8%, representing improvements of 3.8% and 3.1%, respectively, over the original model. The model size is 4.1 M, and its FPS is 144.1, meeting the requirements for real-time and lightweight portable deployment. [ABSTRACT FROM AUTHOR]

As electronic waste poses environmental challenges, exploring eco-friendly alternatives becomes imperative. In this review, the introduction reveals the disposal problem of existing printed circuit boards (PCBs) and the potential impacts of implementing biodegradable PCBs towards the United Nations Sustainable Development Goals. Various biodegradable materials, including polylactic acid, cellulose/cellulose acetate, silk proteins, gelatin, polyvinyl alcohol, mycelium, and wood, were evaluated for their properties and suitability in PCB manufacturing. Each material is scrutinised for its suitability in creating environmentally friendly circuit boards. The study meticulously analyses these biodegradable PCBs' electrical, mechanical, thermal and decomposition properties, providing insights into their performance under various conditions. The article also explores different fabrication methods and their advantages and limitations for manufacturing biodegradable PCBs. Solvent and non-solvent based decomposition of the biodegradable PCBs were revealed. The research outcome on a balance between hygroscopic property and degradability of biodegradable PCBs is revealed. The narrative extends to encompass the challenges and issues associated with the Design-for-Manufacturing processes and life cycle assessment of biodegradable PCBs, shedding light on potential hurdles and areas for improvement. The article concludes with a forward-looking perspective on the future of biodegradable printed circuit boards, environmentally friendly fire-retardants, a proposal for alternative standards for biodegradable PCBs, and their increasing role in sustainable electronics. [ABSTRACT FROM AUTHOR]

PVC Composites reinforced with non-metallic printed circuit boards (PCBs) offer a groundbreaking solution to the escalating e-waste crisis, as it integrates sustainable practices with enhanced material performance. Electronic waste (e-waste) [...]

Abstract The development of electric vehicles (EVs) has been incremental because EVs satisfy a significant demand for energy sources. Electronic control unit (ECU) is an important component that processes the electric signals received from various sensors for generating the control signals for the actuators. Automotive control systems were initially operated manually throughout the automotive revolution based on the responses of input signals received from ECUs and drivers. Most of the functions in EV are controlled by the ECU and every ECU consumes power at all times even if it is not in use. The larger power consumption of passive ECUs like adaptive lighting systems (ALS), automatic wiper systems (AWS) brake light systems (BLS), etc., affect the life of ECUs and the range of EVs. This article is primarily concerned with limiting power consumption by switching the power supply to the passive ECUs based on their requirements. Hence, to achieve the objective, the intelligent zone (i-zone) based master ECU is triggered to activate the slave ECUs. Designing suites including Proteus and KiCAD were used for designing the circuits including master as well as slave ECU. This prototype is built using three secondary ECUs such as ALS & AWS and BLS which are controlled using i-zone-based master ECU. The performance of this implemented design is evaluated, and it is discovered that almost 40% of the battery consumption is reduced. This i-zone-based master ECU and all its slave ECUs manage power while ensuring the safety and reliability of EVs.

The development of electric vehicles (EVs) has been incremental because EVs satisfy a significant demand for energy sources. Electronic control unit (ECU) is an important component that processes the electric signals received from various sensors for generating the control signals for the actuators. Automotive control systems were initially operated manually throughout the automotive revolution based on the responses of input signals received from ECUs and drivers. Most of the functions in EV are controlled by the ECU and every ECU consumes power at all times even if it is not in use. The larger power consumption of passive ECUs like adaptive lighting systems (ALS), automatic wiper systems (AWS) brake light systems (BLS), etc., affect the life of ECUs and the range of EVs. This article is primarily concerned with limiting power consumption by switching the power supply to the passive ECUs based on their requirements. Hence, to achieve the objective, the intelligent zone (i-zone) based master ECU is triggered to activate the slave ECUs. Designing suites including Proteus and KiCAD were used for designing the circuits including master as well as slave ECU. This prototype is built using three secondary ECUs such as ALS & AWS and BLS which are controlled using i-zone-based master ECU. The performance of this implemented design is evaluated, and it is discovered that almost 40% of the battery consumption is reduced. This i-zone-based master ECU and all its slave ECUs manage power while ensuring the safety and reliability of EVs. [ABSTRACT FROM AUTHOR]

The work in this paper incorporated printed circuit board (PCB) technology into micro-direct methanol fuel cells ^DMFCs) and conjectured and verified the performance degradation factors of PCB current collectors in μDMFCs by testing different designed configuration μDMFCs. The experiment results showed that all kinds of PCB coating can benefit from the porous stainless-steel plates covering to a great extent. At the end of 48 h discharging, μDMFCs with porous stainlesssteel plates between MEA and PCB coating achieved higher performance than those of the direct contacting series. It can be inferred from various types of experimental data that because of stainless-steel porous plate isolating, the impact of corrosion on the surface of the PCB electrode plate was reduced to a certain extent. The corrosion of the electrode plate was slowed down in the μDMFC discharging as a result of the passivation behavior on the iron surface and a decrease in corrosion current. Consequently, the attenuation of the PCB performance was delayed. The conclusion of this work explores a practical direction to enhance the cost-effectiveness of fuel cells, promoting the largescale application of DMFCs in the future. [ABSTRACT FROM AUTHOR]

This study focuses on the effects of reducing the diameter of rivets used in Friction Riveting due to the need for downscaling when joining assemblies on a smaller scale. The Friction Riveting process has shown promising feasibility for a variety of material combinations and applications in the transportation industry. Recent research has explored the potential application of this technique in electronics, specifically for the assembly of printed circuit boards (PCBs), using AA-2024-T351 rivets on thin glass-fiber-reinforced epoxy substrates (FR4). The joint formation of joints produced with PCBs was investigated in terms of process temperature evolution, microstructural changes, and mechanical properties. Joints were obtained at process temperatures ranging from 285 ºC to 368 ºC. The use of 4 mm rivets resulted in extensive delamination, weak joint mechanisms, and cracking, impaired by the different coefficients of thermal expansion of the materials involved. Reducing the rivet diameter to 3 mm significantly improved joint quality. A further reduction to 2.5 mm minimized delamination but led to insufficient anchorage and cracking. Joints produced with a 3 mm rivet diameter achieved the highest ultimate tensile force of 276 N. This study sets the foundation for applying the Friction Riveting process to practical PCB assemblies, demonstrating that optimizing the process parameters to the diameter-to-thickness ratio can balance sufficient rivet anchoring, minimize delamination, and reduce cracking. [ABSTRACT FROM AUTHOR]

Multilayer ceramic capacitors (MLCCs) consist of multiple ceramic layers causing vibration owing to its piezoelectric characteristics. The vibrations are transmitted to the printed circuit board (PCB), causing acoustic noise. The mounting location and direction of the MLCC are crucial factors for reducing the acoustic noise. This paper presents a novel method for determining the optimal location and direction of MLCCs to reduce the acoustic noise. The excitation force of MLCC was simplified to calculate the vibroacoustic response of the PCB efficiently. Two design variables representing the MLCC location and direction were developed, and optimization problems were defined to minimize the acoustic noise. To validate the proposed method, the optimization problems were solved for an M.2 solid-state drive model under various scenarios. The results demonstrated that, on average, the overall sound power level was reduced by 4.59 dB for a single MLCC and 6.04 dB for multiple MLCCs. [ABSTRACT FROM AUTHOR]

This paper proposes an automated inspection approach for printed circuit boards (PCBs) that can accurately locate defects to solve the issues of low precision, complex equipment, and high cost. Digital image processing techniques are utilized in this method, including filtering, image segmentation, feature extraction, alignment, and mathematical morphology processing. To overcome the Otsu thresholding segmentation algorithm's high computational cost and poor real-time performance, a particle swarm approach is optimized to increase image segmentation efficiency. Meanwhile, combining the benefits of the FLANN algorithm and the SURF method, matching image feature points is done based on the SURF algorithm. The performance of matching image feature points is improved. In addition, the alignment error of the images is reduced. According to experimental results, the improved PCB defect detection algorithm demonstrated 98.9% accuracy, with remarkable efficiency and accuracy, and can satisfy PCB defect detection requirements. [ABSTRACT FROM AUTHOR]

The finite element modeling of electronic boards is a challenging task due to the complexity of the multi-component board structure. Hence, it is acceptable to attain equivalent orthotropic in-plane mechanical properties and use them throughout the finite element analysis (FEA) simulations. This paper aims to present an artificial intelligence-based methodology, using the artificial neural networks (ANNs), to estimate the in-plane mechanical properties of the printed circuit boards (PCB). In this methodology, the ANN technique used FEA data to find the relationship between the first 10 natural frequencies and the mechanical properties, that is, modulus of elasticity, Poisson's ratio and the shear modulus, of the test board. Subsequently, the experimentally derived natural frequency data is then imported to the ANN model to identify the equivalent orthotropic properties. The ANN-predicted properties are plugged back into FEA and provided natural frequencies and mode shapes that are in great match with experimental results. [ABSTRACT FROM AUTHOR]

Substrate materials for printed circuit boards must meet ever-increasing requirements to keep up with electronics technology development. Especially in the field of high-frequency applications such as radar and cellular broadcasting, low permittivity and the dielectric loss factor are key material parameters. In this work, the dielectric properties of a high-temperature, thermoplastic PEEK/PEI blend system are investigated at frequencies of 5 and 10 GHz under dried and ambient conditions. This material blend, modified with a suitable filler system, is capable of being used in the laser direct structuring (LDS) process. It is revealed that the degree of crystallinity of neat PEEK has a notable influence on the dielectric properties, as well as the PEEK phase structure in the blend system developed through annealing. This phenomenon can in turn be exploited to minimize permittivity values at 30 to 40 wt.-% PEI in the blend, even taking into account the water uptake present in thermoplastics. The dielectric loss follows a linear mixing rule over the blend range, which proved to be true also for PEEK/PEI LDS compounds. [ABSTRACT FROM AUTHOR]

Power Electronics Converters (PEC) play a crucial role in the operation of many modern electrical systems and devices. Despite their widespread use, the lack of an efficient and cost-effective disassembly process can limit their repairability, refurbishability, remanufacturability and, ultimately, recyclability, thus hindering the circularity of products. In order to improve their circularity, it is important to assess their ease of disassembly. Therefore, this paper investigates the applicability of the "ease of Disassembly Metric" (eDiM), which is referenced in the material efficiency standards, Benelux repairability assessment method, and Repair Scoring System (RSS), to analyze the ease of disassembly of energy-related products. After identifying the limitations of the eDiM method, we refined and adapted it to make it more suitable for Printed Circuit Board (PCB)-based PEC, and thus propose a PCB-based disassemblability assessment method allowing the implementation of quantifiable requirements supporting their circularity. This standardized approach, at the PCB level, can improve the circularity of such products by facilitating design enhancements. With this approach, policymakers and designers can contribute more effectively to the transition to a circular economy in PCB electronics, particularly in the field of power electronics. [ABSTRACT FROM AUTHOR]

Copyright of Electronic Components & Materials is the property of Electronic Components & Materials and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to improve the environmental friendliness of the film stripping solution for printed circuit boards, through experimental research, the formula of the eco-friendly film stripping solution with inorganic alkali as the main component was determined to contain: inorganic base NaOH at 0.5 mol/L, film breaker diethylene glycolmonobutyl ether at 10 mL/L, surfactant alcohols R at 5 mL/L, tin protectant potassium citrate at 1 g/L, with the remainder pure water. The film stripping solution was found to be colorless and transparent, maintaining a stable state. Under the condition of a temperature of 50 ℃, the film was removed within 50～70 s, the size of the film ranged from 5 to 10 mm, the average tin thickness variable was less than 0.5 μm, and the ammonia nitrogen value was measured at 4.632 mg/L. Comparing the film stripping solution with products from the same production line, it was found that the film stripping performance of the two was extremely close. The eco-friendly film stripping solution exhibited lower ammonia nitrogen value and chemical oxygen demand(COD) values, which not only met production needs but also offered good environmental friendliness, thereby reducing the treatment cost of the film stripping waste liquid.

This article discusses the development and analysis of a broadband filter capable of suppressing specific frequencies of wireless applications at 4.7 GHz for WLAN, 8.3 GHz, and 11.5 GHz (for satellite communication) by combining a T-shaped stub loaded resonator with a central square ring to achieves high performance and compact size within the bandwidth of interest. The filter achieves low signal loss of 0.4 dB across the entire passband of 14.9 GHz bandwidth, good reflection suppression exceeding 10 dB, and independently adjustable multi stopbands. It utilizes a simple planar topology for a small footprint of 0.52 λg × 0.32 λg, where λg represents the wavelength at 4.7 GHz. The proposed filter evaluated using classical method an even-odd-mode analysis, and a 3D software tool HFSS-15 is used for simulations. The physical prototype is built on a Rogers RO-4350 substrate using LPKF S63 ProtoLaser machine. To confirm the accuracy and performance of the prototype, measurements were conducted using a ZNB20 vector network analyser. The simulations and measurement results confirm its effectiveness, paving the way for applications in various fields such as radar systems, medical imaging, and wireless communication.

Printed Circuit Boards (PCBs) are essential components of electronic devices containing valuable silver metal. Using sustainable methods, silver recovery from electronic trash, like PCBs, demonstrates excellent promise. This research’s objective is to determine the optimum leaching time and solid-to-liquid (S/L) ratio for extracting silver from PCB using deep eutectic solvent (DES) composed of choline chloride and glycerol (glyceline DES). The binary DES’s leaching performance was then compared to choline chloride, glycerol, and citric acid ternary systems. Fourier Transform Infrared Spectroscopy (FTIR) was carried out to analyze the bond interactions. X-ray fluorescence spectrometry (XRF) was employed to determine the PCB’s metal concentration prior to and after the leaching process. Ternary DES was viscous, colorless, stable for 60 days, and less acidic than binary DES, with a 1.21 g/mL density. FTIR peak broadening and shifting indicated the formation of a new hydrogen bond and proved a successful synthesis of ternary DES. XRF result showed that PCB’s initial silver metal content was 2.32%. The optimal silver leaching from PCB using glyceline DES was achieved after 16 hours, with a 1/20 solid-to-liquid ratio. Ternary DES demonstrated a silver leaching efficiency of 93.65%, surpassing 86.77% of glyceline. Ternary DES synthesized in this study has the potential to serve as an efficient and environmentally friendly solvent for extracting silver from PCB, providing a sustainable approach to managing electronic waste.

A large number of printed board circuits (PCBs) are analyzed by X-ray imaging in reverse engineering for the purpose of identifying their connections, their damage, and how they are linked together. Using this method, an X-ray is passed through single or multi-layer boards in order to determine how they are connected and how the parts are arranged. According to the findings, there is fogging in the radiographs due to X-ray scattering and the thinness of copper connections on the boards as well as the small sizes of electronic components. This research employs the Modified Total Variation method (MTV) with alternating gradient, which is an iterative method based on gradient changes in Total Variation, to increase contrast. Based on the results of the implementation of the MTV algorithm on radiographs of various ranges, the contrast has increased, and besides the copper connections, the internal components of the electronic components have also become clearer. Reconstructed images show a contrast improvement of approximately 20 to 40%, according to experts. Using this information, it is possible to repair or build boards in reverse engineering.