Abstract: A computer system includes a motherboard to which a selected one of various processor boards can be coupled via an adaptor. The boards include a CPU and a heat transfer member. The adaptor includes core logic such as a Northbridge module and power control circuitry. The adaptor is pin connectable to the motherboard and the various processor boards are each pin connectable to the adaptor. Alternatively, the adaptor and processor boards can be replaced with a processor module including features of the processor boards and the adaptor. The processor module is also pin connectable to the motherboard at the same connection used by the adaptor.

Abstract: An interconnect sheet for connecting multiple layers of a circuit board for the manufacture of high interconnect density PWBs. The interconnect sheet preferably comprises an area array grid of 0.003 inch solder columns having a 0.006 inch pitch. The interconnect sheet is preferably used to attach two or more multi-layer boards by placing one sheet at every interconnect surface. This interconnect mechanism has an advantage of redundancy of contact and therefore lower susceptibility to failure than other methods. The interconnect sheet of the present invention also offers a large tolerance for registration error without shorting adjacent pads. The preferred method of fabrication of the interconnect sheet begins with creating equally spaced holes through a 0.5 ounce double sided laminate comprising a dielectric sheet and copper plates on either side of the dielectric. These holes are filled with solder paste and the sheet undergoes a baking process to shrink the paste.

Abstract: An inexpensive method for fabricating a staggered edge connector for a circuit board. The method is cost effective and includes numerous advantages over the prior art, including allowing more area for signal routing and removing the problems associated with capacitive stubs on edge connector traces associated with prior art designs. The method begins with creating a staggered plurality of blades or fingers. A plating bus is formed on these staggered blades by connecting a gold plating bus to one of the contact pads and then shorting together or connecting the signal lines via a shorting bus. The shorting bus is placed flush with the innermost edge of the edge connector well outside of the actual wipe area of the connectors. The board then undergoes a standard semi-additive process, as well as a final etch and subsequent gold plating. The shorting bar is then drilled out.

Abstract: An interconnect sheet for connecting multiple layers of a circuit board for the manufacture of high interconnect density PWBs. The interconnect sheet preferably comprises an area array grid of 0.003 inch solder columns having a 0.006 inch pitch. The interconnect sheet is preferably used to attach two or more multi-layer boards by placing one sheet at every interconnect surface. This interconnect mechanism has an advantage of redundancy of contact and therefore lower susceptibility to failure than other methods. The interconnect sheet of the present invention also offers a large tolerance for registration error without shorting adjacent pads. The preferred method of fabrication of the interconnect sheet begins with creating equally spaced holes through a 0.5 ounce double sided laminate comprising a dielectric sheet and copper plates on either side of the dielectric. These holes are filled with solder paste and the sheet undergoes a baking process to shrink the paste.

Abstract: An optimal routing methodology for routing high I/O density packages which minimizes the number of PCB layers required. One feature of this routing methodology comprises treating respective I/O that are routed at the top layer of the package as surface mount technology (SMT) pads without dropping vias within the BGA grid, as is commonplace in the industry. This facilitates the use of fewer escapes and allows for more efficient use of the available space. Signal lines on the top layer of the package which must be routed to other layers of the PCB are connected to vias outside of the area of local high signal density on the printed circuit board. The placement of vias outside the area of local high density, i.e., in a depopulated area, reduces the number of layers necessary in the PCB to properly route the signals. This placement also facilitates the use of filtering capacitors to meet EMI requirements. In addition, all voltage pins are placed on the innermost or outermost grids and have clearanced vias.

Abstract: A rework process for ball grid array (BGA) packages which allows for reuse of devices that have been removed for lack of integrity of solder interconnections. The process uses a rework tool which comprises a plate including one or more depressions corresponding to the contours of inverted BGA packages. A BGA package to be reworked is placed in a respective depression with what remains of the original solder ball grid facing upward. The residual solder balls are wicked away, thus leaving the BGA package with the pads that the solder balls were attached to being exposed. A stencil with BGA patterns punched into it is then placed over the rework tool and solder paste is screened onto the rework tool so that the solder is deposited on the BGA pads via the openings in the stencil. The entire fixture is then subjected to a reflow process to cause the solder to ball up during this process.

Abstract: A method and apparatus for manufacturing large area multilayer interconnects for electronic substrates and circuit boards uses high density area array interconnections that are created by solid state diffusion. Two or more pretested subsections are electrically and mechanically joined together to simultaneously form a multilayer substrate without employing a flow-type connection where the conductive interconnect material is entirely in a liquid phase at some point during the joining process. Each substrate is comprised of a planar dielectric substrate having a plurality of conductive layers. On at least one surface of the substrate a conductive pad lay is formed having a plurality of interconnect pads. The interconnect pads are positioned at a uniform height above the surface of the dielectric substrate and include a base metal layer, a top metal layer with at least one of the conductive pad layers have a donor metal disposed on top of the top metal layer.