scholarly journals Special Articles: Assembly Technology Trends of Smallest, Thinnest and Lightest Electronic Equipment by Thin Multilayer Boards. Canon Camcorder with High Density Printed Circuit Board.

Author(s):  
Motoo KUMAGAI
2021 ◽  
Vol 11 (6) ◽  
pp. 2808
Author(s):  
Leandro H. de S. Silva ◽  
Agostinho A. F. Júnior ◽  
George O. A. Azevedo ◽  
Sergio C. Oliveira ◽  
Bruno J. T. Fernandes

The technological growth of the last decades has brought many improvements in daily life, but also concerns on how to deal with electronic waste. Electrical and electronic equipment waste is the fastest-growing rate in the industrialized world. One of the elements of electronic equipment is the printed circuit board (PCB) and almost every electronic equipment has a PCB inside it. While waste PCB (WPCB) recycling may result in the recovery of potentially precious materials and the reuse of some components, it is a challenging task because its composition diversity requires a cautious pre-processing stage to achieve optimal recycling outcomes. Our research focused on proposing a method to evaluate the economic feasibility of recycling integrated circuits (ICs) from WPCB. The proposed method can help decide whether to dismantle a separate WPCB before the physical or mechanical recycling process and consists of estimating the IC area from a WPCB, calculating the IC’s weight using surface density, and estimating how much metal can be recovered by recycling those ICs. To estimate the IC area in a WPCB, we used a state-of-the-art object detection deep learning model (YOLO) and the PCB DSLR image dataset to detect the WPCB’s ICs. Regarding IC detection, the best result was obtained with the partitioned analysis of each image through a sliding window, thus creating new images of smaller dimensions, reaching 86.77% mAP. As a final result, we estimate that the Deep PCB Dataset has a total of 1079.18 g of ICs, from which it would be possible to recover at least 909.94 g of metals and silicon elements from all WPCBs’ ICs. Since there is a high variability in the compositions of WPCBs, it is possible to calculate the gross income for each WPCB and use it as a decision criterion for the type of pre-processing.


2018 ◽  
Vol 193 (3-4) ◽  
pp. 578-584 ◽  
Author(s):  
Xavier de la Broïse ◽  
Alain Le Coguie ◽  
Jean-Luc Sauvageot ◽  
Claude Pigot ◽  
Xavier Coppolani ◽  
...  

Author(s):  
Sh. A. Yusufov ◽  
A. M. Ibragimova ◽  
S. A. Peredkov ◽  
T. E. Sarkarov ◽  
R. G. Mitarov

Objectives. The article discusses a thermoelectric cooling system (TECS) for ensuring the thermal regime of modular electronic equipment (MEE) located in a cabinet. The main task of the experimental studies is to determine the temperature dependencies of the air-cooled heat-generating elements of a printed circuit board simulator according to TEСS parameters.Method. In order to conduct experimental studies of a thermoelectric cooling system for printed circuit boards in cassette units using a thermoelectric cooling system, a prototype designed and manufactured in the laboratory was studied on a testing stand.Result. The directions of constructive solutions for using a TECS device are presented along with a description of the testing stand and procedure. The dependencies of the temperature of the printed circuit board simulator on the heat power taken away by the TECS are considered along with the temperatures of hot and cold junctions, the air flow velocity and the distance between the electronic boards.Conclusion. The operability of the developed MEE cooling system is confirmed by the experimental studies; the specified cooling method has advantages over conventional forced or natural method and can achieve the temperatures required by the technical operating conditions; when choosing a fan to provide forced circulation of the air flow in the system, it is necessary to take into account the speed of the air flow in the channel; it is necessary to reserve the power of the power supply for the TECS operation in proportion to the power of the heat sources. An important additional point for the functioning of the thermoelectric cooling device is the necessity of ensuring the effective removal of heat from the hot junctions of the thermoelectric module without which it is impossible to use the proposed system. 


1999 ◽  
Vol 39 (9) ◽  
pp. 1337-1341 ◽  
Author(s):  
S. Zhang ◽  
J. De Baets ◽  
A. Van Calster

1992 ◽  
Vol 15 (4) ◽  
pp. 418-425 ◽  
Author(s):  
A. Takahashi ◽  
N. Ooki ◽  
A. Nagai ◽  
H. Akahoshi ◽  
A. Mukoh ◽  
...  

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