Technical Library | 2021-09-29 13:35:21.0
In PCB circuit assemblies the trend is moving to more SMD components with finer pitch connections. The majority of the assemblies still have a small amount of through hole (THT) components. Some of them can't withstand high reflow temperatures, while others are there because of their mechanical robustness. In automotive applications these THT components are also present. Many products for cars, including steering units, radio and navigation, and air compressors also use THT technology to connect board-to-board, PCB's to metal shields or housings out of plastic or even aluminium. This is not a simple 2D plain soldering technology, as it requires handling, efficient thermal heating and handling of heavy (up to 10 kg) parts. Soldering technology becomes more 3D where connections have to be made on different levels. For this technology robots using solder wire fail because of the spattering of the flux in the wires and the long cycle time. In wave soldering using pallets the wave height is limited and pin in paste reflow is only a 2D application with space limitations. Selective soldering using dedicated plates with nozzles on the solder area is the preferred way to make these connections. All joints can be soldered in one dip resulting in short cycle times. Additional soldering on a small select nozzle can make the system even more flexible. The soldering can only be successful when there is enough thermal heat in the assembly before the solder touches the board. A forced convection preheat is a must for many applications to bring enough heat into the metal and board materials. The challenge in a dip soldering process is to get a sufficient hole fill without bridging and minimize the number of solder balls. A new cover was designed to improve the nitrogen environment. Reducing oxygen levels benefits the wetting, but increases the risk for solder balling. Previous investigations showed that solder balling can be minimized by selecting proper materials for solder resist and flux.
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XGR Technologies is focused on providing innovative, board level EMI shielding solutions.
Technical Library | 2020-07-02 13:16:32.0
Principle of shielding 1 The principle of shielding is creating a conductive layer completely surrounding the object you want to shield. This was invented by Michael Faraday and this system is known as a Faraday Cage. 2 Ideally, the shielding layer will be made up of conductive sheets or layers of metal that are connected by means of welding or soldering, without any interruptions. The shielding is perfect when there is no difference in conductivity between the used materials. When dealing with frequencies below 30 MHz, the metal thickness affects shielding effectiveness. We also offer a range of shielding methods for plastic enclosures. A complete absence of interruptions is not a realistic goal since the Faraday cage will have to be opened from time to time so electronics, equipment or people can be moved in or out. Openings are also needed for displays, ventilation, cooling, power supply, signals etc. 3 Shielding works in both directions, items inside the shielded room are shielded from outside influences. (Fig. 3.1)
EZ-BoardWare is a range of SMT PCB Hardware from Harwin that allows simplified EMC shielding, improves cable management and solves tricky PCB layout issues. Packaged in EIA-481-2 compliant tape & reel packaging the products integrate simply into exis
EZ-BoardWare is a range of SMT PCB Hardware from Harwin that allows simplified EMC shielding, improves cable management and solves tricky PCB layout issues. Packaged in EIA-481-2 compliant tape & reel packaging the products integrate simply into exis
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Mat-tech is your specialist in high-tech soldering & brazing. Whether it's developing a new product or improving an existing product, we provide the perfect joint.
Harwin's range of EMC shielding products improve PCB layout by eliminating the need for soldering cans to the board. This wide range of products are suitable for every stage of your process, from prototyping through to volume manufacturing. Free Sa
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Soldertools.net is an online storefront for a variety of product categories related to PCB assembly, PCB rework and solder training.
New Equipment | Solder Materials
Economical solder for repairing & joining most metals including Aluminum and cast Iron. Has been the standard for cast Iron and galvanized surface repair for over 60 years. Low application temperatures prevent loss of properties and minimize distor
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Specialty materials for SMT Assembly. Solder Paste, Spheres, Tac Fluxes, Flip Chip Fluxes, Solder wi
