Abstract: A solder transfer method which uses an electrically-conductive, e.g., metal, surface, of a stamping or pin or pad as a vehicle to transfer molten solder from a remote solder reserve to a solder joint to be made. In one of the preferred embodiments, a solder deposit previously formed on a surface mount pad during a first reflow step will transfer up to the adjoining contact surfaces by a wicking process to provide the additional solder needed to fabricate a robust solder joint. The method and construction are useful for attaching a daughter board to motherboard, and for surface mounting a long header with multiple pins to the contact surfaces of a PCB without the need to separately add solder during a second reflow step to make a robust solder joint between the contact surfaces.

Abstract: A non-intrusive surface mount interconnect that provides a through-hole interconnect to the opposite side of a PCB board. A headed pin (head up/shank down) can be picked by standard placement equipment from a specially configured pocket tape using a hole that is tightly controlled for pin location. The head of the pin rests on top of the packaging tape preventing the pin from passing through the hole. A tapered section on the pin fits with minimal clearence assuring that a vacuum nozzle on the placement equipment when it descends sees and contacts the head top for vacuum nozzle pick-up.

Abstract: A solder transfer method which uses an electrically-conductive, e.g., metal, surface, of a stamping or pin or pad as a vehicle to transfer molten solder from a remote solder reserve to a solder joint to be made. In on of the preferred embodiments, a solder deposit previously formed on a surface mount pad during a first reflow step will transfer up to the adjoining contact surfaces by a wicking process to provide the additional solder needed to fabricate a robust solder joint. The method and construction are useful for attaching a daughter board to motherboard, and for surface mounting a long header with multiple pins to the contact surfaces of a PCB without the need to separately add solder during a second reflow step to make a robust solder joint between the contact surfaces.

Abstract: A solder transfer method which uses an electrically-conductive, e.g., metal, surface, of a stamping or pin or pad as a vehicle to transfer molten solder from a remote solder reserve to a solder joint to be made. In a preferred embodiment, a solder deposit previously-formed on a surface mount pad during a first reflow step will transfer up to the adjoining contact surfaces by a wicking process to provide the additional solder needed to fabricate a robust solderjoint. When one of the contact surfaces is a contact or pin on a first PCB, and the other contact surface is a SMT pad on a second PCB serving, for example, as a memory card, the process of the invention makes for an easy SMT processed attachment of the memory card to the first PCB without the need to add solder during a second reflow step to make a robust solder joint between the contact surfaces.

Abstract: Upper and lower planar circuit boards are connected in spaced apart parallel relationship by a plurality of contacts each made of a conductive pin, insulative collar and solder ball. The upper ends of the pins are inserted in plated though holes in the upper circuit board and soldered thereto by wave soldering or re-flow. The pins have shoulders to establish the penetration of the pins into the upper circuit board. The lower ends of the pins are bonded to conductive pads on the lower circuit board via the solder balls that are maintained in substantially spherical configuration by the insulative collars and accommodate variations in board co-planarity or pin length. Where the lower ends of the pins do not contact their corresponding conductive pads the volume of solder in the solder balls allows reliable fillet solder joints to be formed.

Abstract: Several pin transfer assemblies are disclosed that utilize the surface tension of liquids for picking up and dispensing minute volumes of liquid from wells in a first well plate to a flat substrate surface or into wells in a second well plate. In one embodiment, a plurality of pins reciprocate through complementary arrays of holes in a base plate and an overlying spring plate biased apart by coil springs located around the periphery of the base plate. A foam layer sits on top of the spring plate and a weight plate sits on top of the foam layer. A single coil spring is positioned between a center of the weight plate and the cover to push the weight plate downwardly. The periphery of the cover guides the vertical movement of the weight plate and is connected to the periphery of the base plate. The periphery of the base plate is supported by a frame used to register the pin assembly in a receptacle of a manual or automated liquid transfer apparatus.

Abstract: A pin replicator is disclosed for dispensing minute volumes of liquid onto a substrate surface in an array in connection with drug discovery, diagnostic analysis, and other applications. The pin replicator comprises a base plate, a plurality of pins reciprocable through corresponding holes in the base plate, and a free floating weight plate resting on top of the upper ends of the pins. The weight plate biases the pins toward their fully extended lowered positions. A cover attaches to the base plate, encloses the pins and weight plate and guides the weight plate during vertical movement thereof. The pin replicator can be moved downwardly toward a first micro titer plate so that a lower end of each of the pins contacts the sample liquid in the corresponding well a sufficient amount to pick up and retain a small quantity of the sample liquid due to surface tension.

Abstract: Upper and lower planar circuit boards are connected in spaced apart parallel relationship by a plurality of contacts each made of a conductive pin, insulative collar and solder ball. The upper ends of the pins are inserted in plated though holes in the upper circuit board and soldered thereto by wave soldering or re-flow. The pins have shoulders to establish the penetration of the pins into the upper circuit board. The lower ends of the pins are bonded to conductive pads on the lower circuit board via the solder balls that are maintained in substantially round configuration by the insulative collars and accommodate variations in board co-planarity or pin length. Where the lower ends of the pins do not contact their corresponding conductive pads the volume of solder in the solder balls allows reliable fillet solder joints to be formed.

Abstract: A header includes a substrate made of an insulative material that has a plurality of through holes formed therein extending between upper and lower sides of the substrate. Plating is applied to the through holes to form conductive cylinders with upper and lower ends. A plurality of solder balls are attached to corresponding upper and lower ends of the conductive cylinders. A pair of circuit boards can be mechanically and electrically interconnected with the solder ball header in spaced apart parallel relationship. The solder balls bond the ends of the conductive cylinders with opposing conductive traces or pads formed on the circuit boards.

Abstract: Several pin transfer assemblies are disclosed that utilize the surface tension of liquids for picking up and dispensing minute volumes of liquid from wells in a first well plate to a flat substrate surface or into wells in a second well plate. In one embodiment, a plurality of pins reciprocate through complementary arrays of holes in a base plate and an overlying spring plate biased apart by coil springs located around the periphery of the base plate. A foam layer sits on top of the spring plate and a weight plate sits on top of the foam layer. A single coil spring is positioned between a center of the weight plate and the cover to push the weight plate downwardly. The periphery of the cover guides the vertical movement of the weight plate and is connected to the periphery of the base plate. The periphery of the base plate is supported by a frame used to register the pin assembly in a receptacle of a manual or automated liquid transfer apparatus.

Abstract: A circuit board interconnect system includes a carrier board with a hybrid solder ball and pin grid array. A plurality of electrically conductive pins extend through the carrier board and are arranged in rows and columns to form a grid array. A first circuit board such as a multi-chip module (MCM) board has a plurality of conductive pads or traces formed on a lower surface thereof that are arranged to form a complementary grid array, i.e. the spacing and location of the conductive pads or traces corresponds to the spacing and location of the pins. A plurality of solder balls are provided with each ball being positioned on top of a corresponding pin so that each solder ball forms a solder connection between a pin and a corresponding conductive pad or trace. A second circuit board such as a computer mother board has a pin connector mounted on an upper surface thereof for individually receiving and providing electrical connection with each of the pins.