Six Sigma: Hermeticity Testing (Fine and Gross Leak) is used to determine the 1] H. Greenhouse, Hermeticity of Electronic Packages (William Andrew. As early as the s, SCHOTT’s Business Unit Electronic Packaging .. glass seal, for instance, hermeticity or seal strength, do not change as a result of. Electronic packaging is the design and production of enclosures for electronic devices ranging . Burn-in · Temperature cycling · Thermal shock · Solderability · Autoclave; Visual inspection; Hermeticity/moisture resistance.
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Electronic packaging is a major discipline within the field of mechanical engineering. The same electronic system may be packaged as a portable device or adapted for fixed mounting in an instrument rack or permanent installation.
Pl can be post-processed to provide conductive surfaces. Articles needing additional references from December All articles needing additional references. Electronic packages are sometimes made by machining solid blocks of metal, usually aluminum, into complex shapes. Quantities tend to be small; sometimes only one unit of a custom design is required. An electronics assembly consists of component devices, circuit card assemblies CCAsconnectors, cables and components such as transformers, power supplies, relays, switches, etc.
This method is used mostly in very large electrical equipment such as utility transformers, to increase breakdown voltage. Some parts may be manufactured by specialized processes such as plaster- and sand-casting of metal enclosures. In the design of electronic products, electronic packaging engineers perform analyses to estimate such things as maximum temperatures for components, structural resonant frequencies, and dynamic stresses and deflections under worst-case environments.
Today, glass-seal packages are hefmiticity mostly in critical elecfronic and assemblies for aerospace use, where leakage must be prevented even under extreme changes in temperature, pressure, and humidity. This also excludes dirt and conductive contaminants such as impure water from sensitive areas.
It’s usually a dielectric fluid, chosen for chemical compatibility with the other materials present. These requirements extend beyond and interact with the electrical design.
Glop-top is a variant of conformal coating used in chip-on-board assembly COB. Examples are integrated circuit chips in ceramic Dual In-line Package form, or complex hybrid assemblies of chip components on elecyronic ceramic base plate.
It can also be used to improve heat transfer, especially if allowed to circulate by packagse convection or forced convection through a heat exchanger. Curing can consist of polymerizing the internal resin or evaporating the solvent, which leaves an insulating dielectric material between different voltage components.
From Wikipedia, the free encyclopedia. After the vacuum is released, the fluid flows into the part. Please help improve this article by adding citations to reliable sources. Views Read Edit View history. Examples are injection molding, transfer molding, vacuum forming, and die cutting. Piece part costs are packagfs, but there is little or no cost for custom tooling, and first-piece deliveries can take as little as half a day.
Mass-market consumer devices may have highly specialized packaging to increase consumer appeal. This page was last edited on 31 Decemberat Printed circuits are primarily a technology for connecting components together, but they also provide mechanical structure. Potting can be done in a pre-molded potting shell, or directly in a mold.
Electronic packaging – Wikipedia
Product safety standards may dictate particular features of a consumer product, for example, external hermiricity temperature or grounding of exposed metal parts.
This article needs additional citations for verification. In some products, such as computer accessory boards, they’re all the structure there is. It is also commonly used in high voltage products to allow live parts to be placed closer together, so that the product can be smaller. Molded plastic cases and structural parts can be made by a variety of methods, offering tradeoffs in piece part cost, tooling cost, mechanical and electrical properties, and ease of assembly.
It provides mechanical and chemical protection of delicate components. High-reliability equipment often must survive drop tests, loose cargo vibration, secured cargo vibration, extreme temperatures, humidity, water immersion or spray, rain, sunlight UV, IR and visible lightsalt spray, explosive shock, and many more.
When void-free potting is required, it is common practice to place the product in a vacuum chamber while the resin is still electrohic, hold a vacuum for several minutes to draw the air out of internal cavities and the resin itself, then release the vacuum. Atmospheric pressure collapses the voids and forces the liquid resin into all internal spaces. It’s widely used on mass-produced items such as axial-lead resistors, and sometimes on printed circuit boards.
Aluminum die castings are more common than iron or steel sand castings. It is most commonly used in electronic toys and low-end devices. Liquid filling can be removed for repair much hsrmiticity easily than potting.
Prototypes and industrial equipment made in small quantities may use standardized commercially available enclosures such as card cages or prefabricated boxes. Punched and formed sheet metal is one of the oldest types of electronic packaging. Potting can be rigid or soft. Hermetic metal packaging began life in the vacuum tube industry, where a totally leak-proof housing was essential to operation. Hrrmiticity design of these products depends on the production method and require careful consideration of dimensions and tolerances and tooling design.
This makes them part of the universe of electronic packaging. It prevents ionization from forming between closely spaced live surfaces and initiating failure. The tool of choice is a numerically controlled vertical milling machine, with automatic translation of computer-aided design CAD files to toolpath command files.