Abstract:
A printed wiring board for carrying a semiconductor chip including a resin base substrate having at least one opening therethrough, a thermo-conductive plate for mounting the semiconductor chip thereon, the plate being inserted into the opening, an insulating adhesive layer covering at least one side of the substrate and an electric circuit formed on the layer. The wiring board of this invention eliminates those disadvantages of the existing resin substrate type and metal core type. In essence, the wiring board of this invention displays excellent heat releasing capability and magnetic shield effect as well as reliable electric insulation.
Abstract:
A damaged binding post on a telephone wire connecting panel is replaced by a binding post having a threaded stem and a polygonal head adapted to seat freely in a hole in the panel. A retaining nut is screwed on the stem and spaced from the surface of said panel. A bridge is placed over the binding post and each of the next adjacent binding posts and a locking nut threaded over each of the stems of said adjacent binding posts, to cause said bridge to bow and provide a bias urging the retaining nut downwardly forcing the replacement post to seat in the hole.
Abstract:
A printed circuit for mounting and connecting a plurality of semiconductor devices is disclosed and includes a planar insulating substrate having multiple conductive layers disposed in overlying relationship within the planar substrate. A plurality of parallel rows of apertures for wire wrap, quick connect or stitch wire contacts are provided for mounting integrated circuit. One side of the printed circuit board includes a plurality of power and ground connections disposed between each pair of parallel rows of apertures so that filter capacitors may be mounted under each integrated circuit, thereby conserving printed circuit board space. In a preferred mode of the present invention, alternate ones of the conductive layers are coupled to a source of electrical power while all remaining conductive layers are gounded. At least two adjacent conductive layers are then utilized to minimize parasitic capacitance by completely surrounding each aperture with a portion of conductive material.
Abstract:
A method and apparatus are shown for use in adding electrical connections to existing printed circuit boards. To this end, apparatus in the form of a multilayered pad is provided which has an adhesive layer over at least part of one face which is responsive to heat so that the pad can be bonded by heat to the surface of a printed circuit board. The other face of the pad includes a layer of stainless steel to which nickel wire can be stitched, or welded. A method according to the invention includes cutting a sheet of pads into individual pads, placing a plurality of pads, adhesive side down, on the surface of a printed circuit board, heating the pads to bond them to the board, and stitching (welding) wire to a succession of pads to complete a series of new connections. Some pads include plated-through-holes enabling connections to be completed from the pads to existing circuitry on the boards and to components mounted in the holes by the use of flow soldering techniques.
Abstract:
Discloses a method for making a coaxial conductor interconnection circuit board, as well as the board per se, by providing a first conductive coating on a substrate, scribing an insulated wire signal conductor pattern on the first coating and a second conductive coating over the wire to provide a conductive shield surrounding the wire, eliminating conductive material from the coatings in clearance areas at terminal points and drilling at the terminal points by laser beam or mechanical drilling to expose the signal conductor.
Abstract:
Previously, hook-up wires were glued to a mounting board by means of spot gluing. As disclosed herein, the insulated hook-up wire is first continuously coated with a coating of hot-melt adhesive and is then placed on the mounting board and simultaneously bonded by means of a heated laying tip of an application tool, similar to a soldering bit. When passing through the laying tip, the hook-up wire is briefly heated, whereby the coating of hot-melt adhesive is melted. The insulating layer of the hook-up wire has a higher temperature stability and is thereby not altered. In the immediately following application of the hook-up wire to the mounting board, the hot-melt adhesive cools and connects the hook-up wire to the mounting board.
Abstract:
A high density dimensionally stable encapsulated wire circuit board and a method of making such a board is described. A photo-curable adhesive having a unique combination of rheological properties is utilized to bond insulated wires to a substrate. The unique combination of rheological properties of the adhesive used in the encapsulated wire circuit boards of this invention include a specified range of values for the Storage Shear Modulus and specified range of values for the Loss Angle ratio.
Abstract:
Certain regions of a printed circuit assembly having mechanically laid wires are formed of two parallel sheets of polyimide film, the circuit assembly being flexible in those regions. The edges of these sheets of film are secured in the region of the edges of the rigid parts of the assembly by means of thermally activated adhesives. In the flexible regions, the wires are embedded in a thermally activated adhesive layer held between the two sheets of polyimide film. This adhesive layer, unlike adhesive layers on the rigid parts, contains no fabric.
Abstract:
A modular printed circuit construction using visual or other representations (1 to 7) which can be arranged so as to produce a visual pattern in which continuous interconnections between the modules appear (automatically as a result of overlapping of individual representations). The composite visual pattern can be used to produce a unitary printed circuit board. Alternatively the individual printed circuit boards can be combined in a board assembly using a mounting frame or edge connectors. Two dimensional extension is possible. Particular applications include microprocessor systems (include parallel processors using a common memory). Bus lines can extend completely across individual representations or the unitary board. The positions of such lines can be determined in dependence on the number of individual representations to which they are common.
Abstract:
Tuning elements are provided for use in varying the inductance of the oscillatory circuits of the transmitter and receiver units of garage door actuators operating at ultra-high frequencies. Each oscillatory circuit is a closed loop circuit fabricated on a printed circuit board. The closed loop circuit comprises a pair of printed circuit conductive paths having a fixed capacitor connected across one of the ends thereof and a discrete generally U-shaped wire connected across the other of the ends thereof. The conductive paths and the U-shaped wire comprise the inductor of the oscillatory circuit. By bending the discrete U-shaped wire at its connections with respect to the plane of the printed circuit board, the inductance of the oscillatory circuit in each unit can be adjusted as needed so that they both operate at the same resonant frequency.