Abstract:
A stand-alone circuit board (3), a packaged surface mount PIN diode (1) and a metal ribbon (9) are mounted together in a new tented diode configuration. The flat end surface of the diode end terminal (4) is attached to a metal trace (5) on the circuit board, positioning the diode in an upstanding position, overlying the metal trace and leaving the other diode end terminal (2) in an elevated position over the circuit board. The metal ribbon wraps over the diode symmetrically extending along opposed sides of the diode to complete an electrical connect on the circuit board. In performance, the configuration emulates that prior configuration employing a thick metal plate backed circuit board. An improved RF switch incorporates the foregoing tented diode configuration.
Abstract:
A fastener for an electrical connector. The fastener (10) includes a fastener body (12) having an opening (16) therethrough for receiving a pin (21). The fastener body (12) includes a plurality of gripping elements (14) protruding into the hole (16) for securing the fastener (10) to the pin (21) when disposed therebetween. The fastener (10) is then soldered to the pin (21) and to a mounting surface (34), such as a printed circuit board, by known soldering techniques.
Abstract:
A strap device clamps soldered wires to a conductive pad to reduce stress on the solder joints and to prevent the wire from springing off of the conductive pad if the solder joint should fail. This is accomplished by forming a conductive strap on a die into a yoke shape. The ends of the strap are then welded to a conductive pad so that the strap's yoke shape defines an opening between the strap and the conductive pad. A wire is inserted into the opening and soldered to form a solder joint between the wire, the strap, and the conductive pad. The strap reduces the stress on the solder joint by increasing its surface area and by clamping the wire to the conductive pad during the high temperature portion of a thermal cycle. If the solder joint should fail, the conductive strap maintains a electro-mechanical connection between the wire and the conductive pad.
Abstract:
One and two piece surface mount pin constructions include excess solder receiving channels. In the one piece construction an elongate channel is provided through a tubular pin which is flared or swaged at the lower end to form a base. In the two piece construction a solid pin is provided at a lower end with a uniform cross section in the form of a regular polygon, such as a square, hexagon or octagon. The resulting edges are press-fit against an internal surface of a sleeve which is also swaged at a lower end to form a base. The spaces between the sleeve and the flat or convex surfaces on the captured end of the pin provide the solder-receiving channels. A bead or shoulder on the pins can provide a stop for a vacuum nozzle. When a flared upper lip is used for this purpose it can also serve as a reservoir or well to receive excess solder beyond the amount that can be received in the channels.
Abstract:
A surface mount electronic reed switch component (10) is provided having a rod-shaped pad element (40) connected in transverse relationship to the outer end (30) of each switch lead (12, 14) of the reed switch (10) to provide a stable surface mounting foot without bending the leads (12,14) to thus avoid adversely affecting the switch gap (28) defined by the inner ends (22,24) of the leads (12,14). Element (40) may be of round, square, rectangular or tubular cross-section.
Abstract:
An electrical connector has first terminals which are surface mounted to respective sides of a substrate and second terminals which extend through an edge surface of the substrate to make electrical connection to an opening provided in the substrate. As the connector is mated to the edge of the substrate, the connector occupies a minimal space on the substrate.
Abstract:
A gold bump contact on an electronic component is solder bonded to a bond pad of a printed circuit board or the like utilizing a solder composed of tin-bismuth alloy. The solder is applied to the bond pad as an electroplate or a paste, after which the gold bump is superposed onto the bond pad. The assembly is heated to a first temperature to melt the solder and thereafter maintained at a temperature less than 150.degree. C. to permit the molten solder to wet the gold surface, after which the assembly is cooled to solidify the solder and complete the connection. Wetting at the relatively low temperature retards dissolution of the gold and thereby reduces formation of unwanted gold tin intermetallic compounds that tend to decrease mechanical properties of the connection.
Abstract:
An electrical connector has first terminals which are surface mounted to respective sides of a substrate and second terminals which extend through an edge surface of the substrate to make electrical connection to an opening provided in the substrate. As the connector is mated to the edge of the substrate, the connector occupies a minimal space on the substrate.
Abstract:
A connection structure between lead frames and a base plate of aluminum nitride, to be applied as a connection structure between components of a semiconductor apparatus, has a base plate made of a sintered body of aluminum nitride on which a semiconductor device is to be mounted. The lead frames are made of iron alloy containing nickel in 29 wt. % and cobalt in 17 wt. %. A silver solder is used for joining the base plate and the lead frames. A surface of the lead frame to be joined to the base plate is clad with a stress relief layer of oxygen-free copper of a high plastic deformability to relieve, by its plastic deformation, a thermal stress caused by a difference between a thermal expansion coefficient of the aluminum nitride base plate and that of the lead frame in a cooling process at the time of soldering. Preferably, only a portion of each lead frame to be joined to the base plate comprises an inner layer of an iron alloy containing 29 wt. % of nickel and 17 wt. % of cobalt, and an outer layer portion of oxygen-free copper.
Abstract:
Hollow lead connection elements are placed in through holes in a one-side printed circuit board and are reflow soldered to the conductors with SMD devices on the conductor side of the board. Components are positioned on the conductor side with their leads passed through the connection elements. The leads are wave soldered to the elements on the side of the board opposite the conductors. The elements may have spring-loaded tongues for securing the leads thereto prior to soldering and a flange on the conductor side of the board.