Electronics Manufacturing Technical Articles
Papers and articles related to SMT, PCB & EMS industry.
- Technical Library
852 SMT / PCB Assembly Related Technical Articles
Aug 15, 2013 | I. Ibrahim, S. Bakar, M. Mokji, J. Mukred, Z. Yusof, Z. Ibrahim, K. Khalil, M. Mohamad
An automated visual PCB inspection is an approach used to counter difficulties occurred in human’s manual inspection that can eliminates subjective aspects and then provides fast, quantitative, and dimensional assessments. In this study, referential approach has been implemented on template and defective PCB images to detect numerous defects on bare PCBs before etching process, since etching usually contributes most destructive defects found on PCBs. The PCB inspection system is then improved by incorporating a geometrical image registration, minimum thresholding technique and median filtering in order to solve alignment and uneven illumination problem. Finally, defect classification operation is employed in order to identify the source for six types of defects namely, missing hole, pin hole, underetch, short-circuit, mousebite, and open-circuit....
Publisher: Universiti Teknologi Malaysia
Aug 14, 2013 | Metcal
This paper discusses how to successfully profile a printed circuit board when reworking Ball Grid Array and Chip Scale Packages....
Manufacturer of high-performance precision rework systems for the electronics bench. Product lines include: Hand Soldering and Desoldering, Convection Rework products, Fume Extraction and Fluid Dispensing tools.
Cypress, California, USA
Aug 13, 2013 | Gustavo Garcia-Cota, Crimping Product Manager, Schleuniger, Inc.
One of the common issues I’ve noticed when visiting shops that use crimp force monitors (CFMs) is that the CFMs are usually turned off, regardless of the brand, because engineers and operators are not using them properly. Why, with all of their benefits, are CFMs not being used regularly by employees? One of the biggest problems is the lack of understanding of the variables affecting the CFM’s ability to detect variations. Crimp quality detection is similar to baking a cake. There are a lot of ingredients and if one ingredient is missing or of bad quality, you likely are not going to achieve your desired result. This article will go back through the basics of a crimp quality detection system and discuss what ingredients or variables you need to consider before switching off that CFM. ...
Publisher: Schleuniger, Inc.
Aug 08, 2013 | Sonal Kaushik, Javed Ashraf
In this project Machine Vision PCB Inspection System is applied at the first step of manufacturing, i.e., the making of bare PCB. We first compare a PCB standard image with a PCB image, using a simple subtraction algorithm that can highlight the main problem-regions. We have also seen the effect of noise in a PCB image that at what level this method is suitable to detect the faulty image. Our focus is to detect defects on printed circuit boards & to see the effect of noise. Typical defects that can be detected are over etchings (opens), under-etchings (shorts), holes etc......
Aug 07, 2013 | Titus T. Suck, Orbotech SA
Inspection and test equipment is expensive, produces nothing and does not contribute to the company’s bottom line! Such may be the thinking of many. But as today’s electronic assemblies use more and ever smaller components that are impossible to inspect manually, and components that are impossible to test electrically, the main question is “What costs are manufacturers absorbing because they do not have an Automated Optical Inspection system?”...
Aug 07, 2013 | Peter Edelstein, Teradyne
PCB architectures have continued their steep trend toward greater complexities and higher component densities. For quality control managers and test technicians, the consequence is significant. Their ability to electrically test these products is compounded with each new generation. Probe access to high density boards loaded with micro BGAs using a conventional in-circuit (bed-of-nails) test system is greatly reduced. The challenges and complexity of creating a comprehensive functional test program have all but assured that functional test will not fill the widening gap. This explains why sales of automated-optical and automated X-ray inspection (AOI and AXI) equipment have dramatically risen......
Aug 07, 2013 | Young Bong Kang
This is a practical technical book written by the author based on 24 years of experience. Almost all SMT books, due partially to a few SMT-related books, put weight on equipment, single process or part technology rather than deal with practical process. The book dealing with practical process know-how is rarely found and this is perhaps the first book in which overall SMT practical processes and standards are presented....
Aug 01, 2013 | Rajan Ambat
Electronic industry uses a number of metallic materials in various forms. Also new materials and technology are introduced all the time for increased performance. In recent years, corrosion of electronic systems has been a significant issue. Multiplicity of materials used is one reason limiting the corrosion reliability. However, the reduced spacing between components on a printed circuit board (PCB) due to miniaturization of device is another factor that has made easy for interaction of components in corrosive environments. Presently the knowledge on corrosion issues of electronics is very limited. This paper reviews briefly the materials used in electronic systems, factors influencing corrosion, types of corrosion observed in electronics, and testing methods....
The Technical University of Denmark has an overall mission of developing and creating value using the natural sciences and the technical sciences to benefit society.
Jul 25, 2013 | Barbara Koczera, An Qi Zhao
Bottom-termination components (BTC), such as QFNs, are becoming more common in PCB assemblies. These components are characterized by hidden solder joints. How are defects on hidden DFN joints detected? Certainly, insufficient solder joints on BTCs cannot be detected by manual visual inspection. Nor can this type of defect be detected by automated optical inspection; the joint is hidden by the component body. Defects such as insufficients are often referred to as "marginal" defects because there is likely enough solder present to make contact between the termination on the bottom-side of the component and the board pad for the component to pass in-circuit and functional test. Should the board be subjected to shock or vibration, however, there is a good chance this solder connection will fracture, leading to an open connection....
Publisher: Flex (Flextronics International)
Jul 18, 2013 | Fan Gao, Karunaharan Rajathurai, Qingzhou Cui, Guangwen Zhou, Irene NkengforAcha, Zhiyong Gu
Lead-free nanosolders have shown promise in nanowire and nanoelectronics assembly. Among various important parameters, melting is the most fundamental property affecting the assembly process. Here we report that the melting behavior of tin and tin/silver nanowires and nanorods can be significantly affected by the surface oxide of nanosolders....
The Chemical Engineering Department boasts an accomplished faculty, a diverse range of programs and degrees and well-established ties to industrial and research institutions.
Lowell, Massachusetts, USA