Abstract:
An encapsulated package for a power magnetic device and a method of manufacture therefor. The power magnetic device has a magnetic core subject to magnetostriction when placed under stress. The package includes: (1) compliant material disposed about at least a portion of the magnetic core and (2) an encapsulant substantially surrounding the compliant material and the magnetic core, the compliant material providing a medium for absorbing stress between the encapsulant and the magnetic core, the compliant material reducing the magnetostriction upon the magnetic core caused by the stress from the encapsulant. In one embodiment, the encapsulant includes a vent to an environment surrounding the package. The vent provides pressure relief for the compliant material, allowing the compliant material to substantially eliminate the magnetostrictive effects.
Abstract:
A surface mountable cover for providing EMI shielding is formed of a composition of a conductive additive suspended within a thermoplastic polymeric material in an amount sufficient to allow the article to reflect and absorb incident electromagnetic radiation. The cover is formed of a material which is solderable to a substrate, such as a printed wiring board. The thermoplastic material has a melting point of greater than about 230°C to allow the thermoplastic material to be used in surface mount technology (SMT) processing. The article and electronic components or circuits covered by the article are affixed to a printed wiring board with SMT processing.
Abstract:
An encapsulated package for a power magnetic device and a method of manufacture therefor. The power magnetic device has a magnetic core subject to magnetostriction when placed under stress. The package includes: (1) compliant material disposed about at least a portion of the magnetic core and (2) an encapsulant substantially surrounding the compliant material and the magnetic core, the compliant material providing a medium for absorbing stress between the encapsulant and the magnetic core, the compliant material reducing the magnetostriction upon the magnetic core caused by the stress from the encapsulant. In one embodiment, the encapsulant includes a vent to an environment surrounding the package. The vent provides pressure relief for the compliant material, allowing the compliant material to substantially eliminate the magnetostrictive effects.
Abstract:
A power magnetic device, a method of manufacture therefor and a power converter are disclosed. The power magnetic device includes: (1) an isolation transformer (240) having a primary winding (245) and a secondary winding (250), (2) a switch (260) coupled to the primary winding, (3) a rectifier (270, 275) coupled to the secondary winding and (4) an encapsulant substantially surrounding the isolation transformer, the switch and the rectifier to join the isolation transformer, the switch and the rectifier into an integrated package, the integrated package having: (a) a first power input (280) coupled to a first end (282) of the primary winding, (b) a second power input (285) coupled to the switch, (c) first and second power outputs (287, 290) coupled to the rectifier circuit and (d) a control input (293) coupled to the switch, the control input allowing the switch to be controlled to couple the primary winding to a source of electrical power (VIN), whereby the power magnetic device converts electrical power into DC electrical power.
Abstract:
Reaction injection molding is used to provide a communications device, e.g., a telephone handset, having a body that contains internal electronics and polymeric material that substantially fill the entire volume of the body. The body thus consists of the internal electronics surrounded or encapsulated by a continuous mass of the polymeric material.
Abstract:
A power magnetic device, a method of manufacture therefor and a power converter are disclosed. The power magnetic device includes: (1) an isolation transformer (240) having a primary winding (245) and a secondary winding (250), (2) a switch (260) coupled to the primary winding, (3) a rectifier (270, 275) coupled to the secondary winding and (4) an encapsulant substantially surrounding the isolation transformer, the switch and the rectifier to join the isolation transformer, the switch and the rectifier into an integrated package, the integrated package having: (a) a first power input (280) coupled to a first end (282) of the primary winding, (b) a second power input (285) coupled to the switch, (c) first and second power outputs (287, 290) coupled to the rectifier circuit and (d) a control input (293) coupled to the switch, the control input allowing the switch to be controlled to couple the primary winding to a source of electrical power (VIN), whereby the power magnetic device converts electrical power into DC electrical power.
Abstract:
An assembly for protecting the active electronic components of an electronic product from the environment and electromagnetic interference (EMI). A method is described where the assembly is formed by providing a metallized flexible enclosure around the electronic product, such as a printed circuit board, and subsequently sealing the metallized flexible enclosure, such that separable connectors can be readily accessed without violating the integrity of the seal. The metallized flexible enclosure includes multiple layers of polymeric materials that provide diffusion barrier properties and a metallic layer that provides both diffusion barrier properties and EMI shielding capabilities. The multiple layer sheet is patterned to optimize the diffusion barrier properties and EMI shielding capabilities. Further, the multiple layer sheet enables efficient, high volume production. Thus, electronic products can be provided with an assembly having an environment protection capability and EMI shielding capability amenable to reliable and cost effective high volume production.
Abstract:
A method for fabricating a coextruded part includes a multiple layer sheet. First, an extruded part (80) is fabricated which can include a complex interior structure. Then, a multiple layer sheet material (82) is formed into a tube surrounding the first extruded part (80) and bonded to the outer surface. Next, the composite structure then enters a second extrusion die (40) and an outer layer of a second polymeric material (84) is coextruded over the structure to form the outer surface. Thus, the multiple layer sheet (82) embedded within the coextruded part imparts diffusion barrier and electromagnetic shielding capabilities to a complex extruded part in a continuous and cost effective manner.
Abstract:
A device, such as a cellular phone, is provided having a component, e.g., a device housing, containing an integral light guide, where the component is formed by co-injection molding. The integral light guide is capable of distributing light from one or more sources through or along the component to distant keys or a distant liquid crystal display, thereby reducing the required number of light sources in the device. In addition, because the component and light guide are co-injection molded in a single step, the complexity and cost of the manufacturing of the component, and thus the overall device, is typically reduced.
Abstract:
A device, such as a cellular phone, is provided having a component, e.g., a device housing, containing an integral light guide, where the component is formed by co-injection molding. The integral light guide is capable of distributing light from one or more sources through or along the component to distant keys or a distant liquid crystal display, thereby reducing the required number of light sources in the device. In addition, because the component and light guide are co-injection molded in a single step, the complexity and cost of the manufacturing of the component, and thus the overall device, is typically reduced.