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A novel low voltage high power multi-phase inverter is presented. Based on an already designed ISCAD machine the specification of an electrical power up to 240 kW at a dc-link voltage below 60 V has to be achieved. For spreading the high currents and the corresponding power losses a 60 phase machine is built up. Each phase is connected with one dedicated half-Bridge, which includes power components...
Function failure was found successively in one type of smart remote controls when using a period of time. With preliminary investigation by electric circuit, low resistance was found between the neighboring pins on failure sample which connected with flexible printed board and rigid printed board, but the pins on good sample were insulated with the others. After peeling off the flexible printed board,...
Electronic systems installed under the dynamic environment such as those on the transportation vehicles, military and aerospace equipment, and handheld mobile devices, are often subjected to harsh vibrations. How to improve the life of these electronic devices is an important issue other than their functional design. In this study, these electronic systems with different installation conditions and...
The process of singulating IC packages such as Quad Flat Pack No-Lead (QFNs) by either a sawing or punching operation results in exposed copper on the sidewalls. This exposed copper surface can oxidize leading to poor or no solder wetting up the sidewall during the assembly operation. The consequence of this oxidized copper surface is either incomplete or no solder fillet formation during the PCB...
In present study, an interesting phenomenon of solder bridging presents in fine pitch BGA device is reported. The failure mechanism is investigated by solder formation modeling, and examined by experimental results of multi-factors evaluation. Results show that the risk of adjacent joints bridging is highly influenced by printed circuit board design attribute. A mathematic model is applied to describe...
In this paper, we studied the problem of IR drop of high performance multilayer printed circuit boards (PCBs). Adaptive mesh is used to simplify the process and improve efficiency. It is found that both vias contact of voltage regulator module (VRM) and the copper planes produce significant IR drop. A novel method for IR drop reduction is proposed, which can significantly reduce the resistance introduced...
In this paper, we studied the problem of IR drop of high performance multilayer printed circuit boards (PCBs). Adaptive mesh is used to simplify the process and improve efficiency. It is found that both vias contact of voltage regulator module (VRM) and the copper planes produce significant IR drop. A novel method for IR drop reduction is proposed, which can significantly reduce the resistance introduced...
In present study, an interesting phenomenon of solder bridging presents in fine pitch BGA device is reported. The failure mechanism is investigated by solder formation modeling, and examined by experimental results of multi-factors evaluation. Results show that the risk of adjacent joints bridging is highly influenced by printed circuit board design attribute. A mathematic model is applied to describe...
This paper examines experimental and simulation techniques for quantifying the statistical variation in coupling within an enclosure populated with circuit boards. The performance of equivalent conductive sheets for modelling and/or experiments is compared with circuit board effects to investigate whether simple equivalent models are valid.
The experiment-based differential and extrapolation techniques to extract frequency-dependent dielectric loss of printed circuit board laminates are proposed. Separation of dielectric loss from conductor loss on substantially rough copper foils is based on the analysis of frequency (ω) components in dielectric and conductor losses. Smooth conductor loss behaves as √ω, while dielectric loss behaves...
A newly developed module with wirebond-less structure is investigated. This structure has multi-pin attached interconnection structure implanted into power circuit board with connecting line between chips and other elements inside the power module. Additionally, heat-spreader-like copper blocks bonded to ceramic insulated substrates performing high thermal conductivity, enable to realize high current...
This paper presents the analysis of temperature rise on PCB. Numerical solutions using Galerkin approach that is one of Finite Element Method (FEM) was used to study and analyze the temperature rise on PCB. Then, an algorithm has been developed using MATLAB. The PCB with four different width of copper is supplied with different range of direct current (DC) from 0.5 to 5 Amperes to capture the data...
In this paper, the author discusses the use of carbon composites, metal carbon composites and two types of carbon Nanopapers in Printed Circuit boards as a thermal control method. The emphasis is on directly mounting active power components on the thermal control layer to minimize cost and assembly complexity. Metal carbon composites, Bucky paper and Long Wall Carbon nanomaterials were acquired from...
This paper presents a low-cost pneumatic micropiston fabricated using Printed Circuit Board for Microelec-tromechanical Systems (PCB-MEMS) technology in which the copper is used as sacrificial layer and the Flame Retardant 4 (FR4) as substrate. Also the typical process of the negative photoresist SU-8 is used to fabricated the structures, i.e, the cylinder and the piston. The geometric shape selected...
This paper describes the fabrication process of a three-dimensional flow focusing device using the PCB-MEMS technology to produce microbubbles with a controlled diameter. The proposed process involves the typical photolithographic steps used in Printed Circuit Board (PCB) fabrication and a low temperature bonding technique based on tin/lead alloy. The fabricated device can be considered as low-cost...
Electronic equipment with sealed enclosures are used in many applications where ruggedness and harsh environment are governing factors. However, the reliability of such equipment will depend on the effective heat rejection capability. Thus, an optimized thermal design is of paramount importance. In the present paper, thermal analysis of a sealed electronic rack is described. Finite Element code NISA...
According to the properties of bioleaching solutions of printed circuit boards (PCBs), copper in the leaching solution were recovery by ion exchange with macroporous styrene iminodiacetic acid chelating resin D401. The bed height of resin, flow rate, pH value on copper adsorption had been studied. Work Exchange Capacity (WEC) of copper increased with increasing bed height of resin and flow rate. The...
This paper presents results from dielectric tests along the surface of the base plate of an IGBT module as well as on printed circuit boards (PCBs). The PCBs have simplified geometries representative for base plates used in IGBT modules. The module will be applied in subsea converters, submerged in a liquid dielectric and exposed to subsea hydrostatic pressure. One base plate was cut to examine geometric...
Along with the increase in circuit density, it becomes more difficult to dissipate heat through the surface of the components. Therefore, the designs and applications for the materials used in heat dissipation as well as high thermal conductivity and low CTE have become the focal point for discussion. In addition, as the high luminance of LEDs is increased and development for brighter LEDs continues,...
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