Abstract:
Apparatus and methods are presented for reinforcing and stiffening a printed circuit board (PCB) in selected locations by utilizing preferentially oriented fibers. Selected fibers within the polymeric material matrix of the PCB fiber-matrix layer are removed and replaced with a similar quantity of fibers in a preferential orientation. Various combinations of layering of modified fiber-matrix layer material with conventional fiber-matrix layer material are presented to achieve the desired PCB stiffening. Printed circuit boards, under the weight of heavy attached electronic components, may deflect or flex along an axis, defined as the characteristic fold. This flexing is exasperated with manufacturing and handling loading, particularly when mounted in a chassis. Preferentially orientated fibers laid transverse to the characteristic fold reinforces the area to resist flexure within the area surrounding the characteristic fold. Reducing PCB flexure is particularly important in locations of the PCB containing surface mount technology (SMT) components, such as ball grid array electronic components. The lead attachment for BGA components is particularly susceptible to PCB flexure resulting in lead fatigue, fracture and failure. The presented methods and apparatus provide PCB stiffening without the addition of external PCB stiffeners and without effecting the PCB overall thickness, fiber to matrix ratio, uniform properties, or dielectric properties.
Abstract:
A description is provided of laminates for printed circuits using unidirectional glass fabric produced with continuous yarn which is twisted, has a low number of twists or zero twisting turns with different gramme weights, interlaced warpwise with a leno interwoven binding using glass yarns of 5.5 to 22 Tex at a spacing of up to 20 cm. The application of these laminates to the manufacture of printed circuits offers advantages in terms of surface roughness and waviness, dimensional stability, evenness and perforability.
Abstract:
A warp-free laminate is produced by winding a first set of strands or filaments about a flat mandrel with a second set of strands being wound transverse to the first set. The two sets may be perpendicular to each other. The filaments are maintained under a controlled tension while being impregnated with a resin and during subsequent cure of the resin. In order to permit the formation of a warp-free product, the winding pattern is such that it forms a mirror image about a neutral axis or plane of symmetry. The winding pattern may be chosen to provide interstices in a predetermined pattern permitting punching out or high speed drilling of hole openings for subsequent printed circuit applications.
Abstract:
The reinforcing fibers in a printed circuit board laminate are arranged in an ordered manner to leave fiber-free zones for the formation of holes. The holes may be oblong to enhance the connection to electrical leads of components mounted on the printed circuit board. The holes may be oriented with their long dimensions transverse to the side of an electrical component, and the electrical component may have its leads correspondingly oriented, to improve wiring flexibility and allow more direct wiring paths.
Abstract:
A method of continuously producing clad composites is disclosed. The cladding is combined with a resin-wet reinforcement and pultruded through a forming and curing die in a single processing step.
Abstract:
A stretchable battery and the method of manufacturing the same. The stretchable battery can be manufactured by using a printing process. The construction of the stretchable battery can comprise a first layer of an elastomer film, a first current collector layer, a layer of cathode, a separating layer, a layer of anode, and a second current collector layer. Metal traces can be used to couple with the first and/or the second current collector layers.
Abstract:
A package board includes a stack structure that includes a circuit layer and a fiber layer. The fiber layer includes at least one first fiber that extends in a first direction and is a non-woven fiber. Also, a prepreg includes a first fiber that is a non-woven fiber; a plurality of second fibers that are spaced apart from the first fiber and are woven fibers; and an insulating layer that fills gaps between the first fiber and the plurality of second fibers.
Abstract:
An electronics assembly includes multiple electronic components coupled to a fabric. Each of the multiple electronic components includes one or more electrical connection points, such as a bond pad or solder bump. The electronics assembly also includes one or more electrically conductive wire braids, one electrically conductive wire braid coupled to one electrical connection point on an electronic component. One of the electrically conductive wire braids interconnects two electronic components, thereby providing an electrical connection between the two electronic components. The electrically conductive wire braid can be attached to the fabric by an adhesive, a stitched thread, which can be either electrically insulated or electrically conductive, or both adhesive and stitched thread. The fabric can be a wearable fabric, such as a shirt or pants, or other form to be worn by a user, such as an armband, waistband, hat or shoes.
Abstract:
A wearable electronics assembly includes one or more electronic modules coupled to a wearable electronics fabric. Each of the one or more electronic modules includes one or more metal foils, each metal foil electrically coupled at one end to an electrical connection point of the electrical module and at another end to an electrically conductive wire. The electrically conductive wire is stitched to the metal foil and to a fabric onto which the electronic module is attached. The electronic module can include one or more electronic components coupled to a printed circuit board. The metal foils can be formed from interconnects on the printed circuit board or the metal foils can be separate elements coupled to the printed circuit board.
Abstract:
Prepregs, laminates, printed wiring board structures and processes for constructing materials and printed wiring boards that enable the construction of printed wiring boards with improved thermal properties. In one embodiment, the prepregs include substrates impregnated with electrically and thermally conductive resins. In other embodiments, the prepregs have substrate materials that include carbon. In other embodiments, the prepregs include substrates impregnated with thermally conductive resins. In other embodiments, the printed wiring board structures include electrically and thermally conductive laminates that can act as ground and/or power planes.