Technical Library | 2020-09-30 19:26:45.0
Introduction •Market trend: Smaller, more efficient, more powerful, run faster •ICs and other sophisticated electronic components typically operate efficiently only under a certain range of temperatures •Operational temperatures must be kept within a suitable range • Excessive heat can damage performance and can even cause system failure
Technical Library | 2011-06-09 13:29:17.0
Flatness measurement of electronic parts and assemblies, or PCB’s, has become increasingly critical as geometries become smaller: finer pitches, smaller solder ball volumes, thinner substrates, etc. Additionally, processing temperatures vary and can pla
Technical Library | 2023-09-26 19:14:44.0
The transition from tin-lead to lead free soldering in the electronics manufacturing industry has been in progress for the past 10 years. In the interim period before lead free assemblies are uniformly accepted, mixed formulation solder joints are becoming commonplace in electronic assemblies. For example, area array components (BGA/CSP) are frequently available only with lead free Sn-Ag-Cu (SAC) solder balls. Such parts are often assembled to printed circuit boards using traditional 63Sn-37Pb solder paste. The resulting solder joints contain unusual quaternary alloys of Sn, Ag, Cu, and Pb. In addition, the alloy composition can vary across the solder joint based on the paste to ball solder volumes and the reflow profile utilized. The mechanical and physical properties of such Sn-Ag-Cu-Pb alloys have not been explored extensively in the literature. In addition, the reliability of mixed formulation solder joints is poorly understood.
Technical Library | 2019-05-02 13:47:39.0
Automating electronics assembly is complex because many devices are not manufactured on a scale that justifies the cost of setting up robotic systems, which need frequent readjustments as models change. Moreover, robots are only appropriate for a limited part of assembly because small, intricate devices are particularly difficult for them to assemble. Therefore, assembly line designers must minimize operational and readjustment costs by determining the optimal assignment of tasks and resources for workstations. Several research studies address task assignment issues, most of them dealing with robot costs as fixed amount, ignoring operational costs. In real factories, the cost of human resources is constant, whereas robot costs increase with uptime. Thus, human workload must be as large and robot workload as small as possible for the given number of humans and robots. We propose a new task assignment method that establishes a workload balancing that meet precedence and further constraints.
Technical Library | 2009-12-14 20:27:54.0
Solder paste is the most recognized form of solder used in electronics assembly today. A surface mount application depends on solder paste to attach the components to the circuit board. However, solder paste may not be the only solution. This is especially true when working with through-hole components or very large devices that require more solder than can be supplied by printed solder paste. In fact, quite often a PCB involves mixed technology that requires more than one form of solder. Solder paste is used for the surface mount components and solder preforms are utilized to attach the leads on through-hole components, avoiding wave or selective soldering.
Technical Library | 2012-11-15 23:38:50.0
First published in the 2012 IPC APEX EXPO technical conference proceedings. As we progress in the 21st century, electronics manufacturing will need more and more precision. Parts will get more complex since more components have to be assembled in smaller spaces. Circuit boards and other electronic assemblies will become more densely populated; spacings between components will be shorter. This will require precision manufacturing and efficient cleaning during and post manufacturing. In addition, with population and technology progressing, larger amount of greenhouse gases will be emitted resulting in higher global warming. Intense research effort is going on to develop new generation of chemicals to address both cleaning and global warming issues. Low global warming solutions in refrigeration and as insulating agents are already in the marketplace.
Technical Library | 2023-11-20 18:18:34.0
When x-ray inspection is used as part of a quality assurance program for any assembled device, steps must be taken early in the design stage to anticipate the use of x-ray inspection later in the development and production processes. This is a lesson that electronic assembly manufacturers learned years ago, and that medical device manufacturers are also discovering. There are several steps involved in learning how to interpret x-ray images, and how to design for x-ray inspection. First, manufacturers need to understand the nature of the x-ray shadow and its modalities; then they need to see how medical device developers and manufacturers are using x-ray inspection; finally, they need to consider taking measures early in the design process to ensure a clear, accurate image when the assembled device undergoes x-ray inspection.
Technical Library | 2019-03-06 21:26:14.0
Electronic assemblies use a large variety of polymer materials with different mechanical and thermal properties to provide protection in harsh usage environments. However, variability in the mechanical properties such as the coefficient of thermal expansion and elastic modulus effects the material selection process by introducing uncertainty to the long term impacts on the reliability of the electronics. Typically, the main reliability issue is solder joint fatigue which accounts for a large amount of failures in electronic components. Therefore, it is necessary to understand the effect of polymer encapsulations (coatings, pottings and underfills) on the solder joints when predicting reliability.This paper presents the construction and validation of a thermo-mechanical tensile fatigue specimen. The thermal cycling range was matched with potting expansion properties in order to vary the magnitude of tensile stress imposed on solder joints
Technical Library | 2009-06-17 18:52:27.0
The increased interest in halogen-free assemblies is a result of Non-Government Organizations (NGOs) exerting pressure on electronic equipment manufacturers to eliminate halogens. The NGOs primary focus is on resolving global environmental issues and concerns. As a result of an increase in the enormous "e-waste" dump sites that have begun showing up around the world, NGOs are pushing consumer electronic manufacturers to ban halogen-containing material in order to produce "green" products. Not only are these sites enormous, but the recycling methods are archaic and sometimes even illegal.This stockpiling and dumping has created growing political and environmental issues. In order to deal with this issue, the question of why halogens are a focal point must be addressed.
Technical Library | 2023-11-14 19:33:57.0
Wave soldering is an established technology and is commonly used where large unit volumes occur with low product variety. However, if a wave soldering machine is getting old or if technological changes or new PCB designs limits its manufacturing capabilities, consideration should be given to whether selective soldering would be a better choice. Anyone who deals with soldering through-hole and surface mount mixed-technology printed circuit assemblies will quickly discover that a selective soldering machine is not only less expensive that wave soldering, but selective soldering also offers the opportunity to meet customer requirements with significantly more flexibility. One such company is Thomas Preuhs GmbH. Located in Geislingen, Germany, Thomas Preuhs GmbH manufactures a variety of electronic assemblies for solar and HVAC data systems, automotive and white goods products as well as electric drive systems.
Manufacturer of PCB depaneling and PCB soldering machines since 2005, products include CE approval V-groove PCB depanelizer, PCB router, PCB punching machine, laser depaneling, hot bar soldering machines and soldering robots.
Liwu Industrial Park, Yuanzhou Town, Boluo
Huizhou, 30 China
Phone: +86-138-29839112
