Abstract: The present invention provides a system and method for employing leaded packaged memory devices in memory cards. Leaded packaged ICs are disposed on one or both sides of a flex circuitry structure to create an IC-populated structure. In a preferred embodiment, leads of constituent leaded IC packages are configured to allowed the lower surface of the leaded IC packages to contact respective surfaces of the flex circuitry structure. Contacts for typical embodiments are supported by a rigid portion of the flex circuitry structure and the IC-populated structure is disposed in a casing to provide card structure for the module.

Abstract: A circuit module is provided in which two secondary substrates or cards or the rigid portions of a rigid flex assembly are populated with integrated circuits (ICs). The secondary substrates are connected with flexible circuitry. One side of the flexible circuitry exhibits contacts adapted for connection to an edge connector. The flexible circuitry is wrapped about an edge of a preferably metallic substrate to dispose one of the two secondary substrates on a first side of the substrate and the other of the secondary substrates on the second side of the substrate.

Abstract: A circuit module is provided in which two secondary substrates or cards or the rigid portions of a rigid flex assembly are populated with integrated circuits (ICs). The secondary substrates are connected with flexible circuitry. One side of the flexible circuitry exhibits contacts adapted for connection to an edge connector. The flexible circuitry is wrapped about an edge of a preferably metallic substrate to dispose one of the two secondary substrates on a first side of the substrate and the other of the secondary substrates on the second side of the substrate.

Abstract: A flexible circuit has contacts for mounting in a socket or card edge connector. The flexible circuit includes integrated circuit devices mounted on both sides of the edge connector contacts. Preferably, the flexible circuit is wrapped about an edge of a rigid substrate and presents contacts on both sides of the substrate for mounting in a socket. Multiple flexible circuits may be overlaid with the same strategy. The flexible circuit may exhibit one or two or more conductive layers, and may have changes in the layered structure or have split layers.

Abstract: Multiple fully buffered DIMM circuits or instantiations are presented in a single module. In a preferred embodiment, memory integrated circuits (preferably CSPs) and accompanying AMBs are arranged in two ranks in two fields on each side of a flexible circuit. The flexible circuit has expansion contacts disposed along one side. The flexible circuit is disposed about a supporting substrate or board to place one complete FB-DIMM circuit or instantiation on each side of the constructed module. In alternative but also preferred embodiments, the ICs on the side of the flexible circuit closest to the substrate are disposed, at least partially, in what are, in a preferred embodiment, windows, pockets, or cutaway areas in the substrate. Other embodiments may only populate one side of the flexible circuit or may only remove enough substrate material to reduce but not eliminate the entire substrate contribution to overall profile.

Abstract: The present invention stacks integrated circuits into modules that conserve board surface area. In a two-high stack or module devised in accordance with a preferred embodiment of the present invention, a pair of integrated circuits is stacked, with one integrated circuit above the other. The two integrated circuits are connected with a pair of flexible circuit structures. Each of the pair of flexible circuit structures is partially wrapped about a respective opposite lateral edge of the lower integrated circuit of the module. The flex circuit pair connects the upper and lower integrated circuits and provides a thermal and electrical path connection path between the module and its application environment. The module has a bailout pattern with a different pitch and/or supplemental module contacts devised to allow combined signaling to the integrated circuits through contacts having a desired ballout footprint.

Abstract: The present invention provides a system and method that mounts integrated circuit devices onto substrates and a system and method for employing the method in stacked modules. The contact pads of a packaged integrated circuit device are substantially exposed. A solder paste that includes higher temperature solder paste alloy is applied to a substrate or to the integrated circuit device to be mounted. The integrated circuit device is positioned to contact the contacts of the substrate. Heat is applied to create high temperature joints between the contacts of the substrate and the integrated circuit device resulting in a device-substrate assembly with high temperature joints. The formed joints are less subject to re-melting in subsequent processing steps. The method may be employed in devising stacked module constructions such as those disclosed herein as preferred embodiments in accordance with the invention. Typically, the created joints are low in profile.

Abstract: The present invention stacks chip scale-packaged integrated circuits (CSPs) into low profile modules that conserve PWB or other board surface area. Low profile structures provide connection between CSPs of the stacked module and between and to the flex circuitry. Low profile contacts are created by any of a variety of methods and materials including, for example, screen paste techniques and use of high temperature solders, although other application techniques and traditional solders may be employed for creating low profile contacts in the present invention. A consolidated low profile contact structure and technique is provided for use in alternative embodiments of the present invention. The CSPs employed in stacked modules devised in accordance with the present invention are connected with flex circuitry. That flex circuitry may exhibit one or two or more conductive layers.

Abstract: A chip stack comprising a flex circuit including a flex substrate having a first conductive pattern disposed thereon and a plurality of leads extending therefrom. Also included in the chip stack are at least two integrated circuit chip packages. The integrated circuit chip packages may be electrically connected to the first conductive pattern of the flex circuit such that the integrated circuit chip packages are positioned upon respective ones of opposed top and bottom surfaces of the flex substrate. Alternatively, one of the integrated circuit chip packages may be positioned upon the top surface of the flex substrate and electrically connected to the first conductive pattern, with the remaining integrated circuit chip package being attached in a non-conductive manner to the bottom surface of the flex substrate such that the conductive contacts of such integrated circuit chip package and the leads collectively define a composite footprint for the chip stack.

Abstract: The present invention provides a flexible circuit connector for electrically coupling IC devices to one another in a stacked configuration. Each IC device includes: (1) a package having top, bottom, and peripheral sides; and (2) external leads that extend out from at least one of the peripheral sides. In one embodiment, the flexible circuit connector comprises a plurality of discrete conductors that are adapted to be mounted between the upper side of a first package and the lower side of a second package. The flexible circuit connector also includes distal ends that extend from the conductors. The distal ends are adapted to be electrically connected to external leads from the first and second packages to interconnect with one another predetermined, separate groups of the external leads. In this manner, individual devices within a stack module can be individually accessed from traces on a circuit card.

Abstract: The present invention stacks integrated circuits into modules that conserve board surface area. In a two-high stack or module devised in accordance with a preferred embodiment of the present invention, a pair of integrated circuits is stacked, with one integrated circuit above the other. The two integrated circuits are connected with a pair of flexible circuit structures. Each of the pair of flexible circuit structures is partially wrapped about a respective opposite lateral edge of the lower integrated circuit of the module. The flex circuit pair connects the upper and lower integrated circuits and provides a thermal and electrical path connection path between the module and its application environment. The module has a ballout pattern with a different pitch and/or supplemental module contacts devised to allow combined signaling to the integrated circuits through contacts having a desired ballout footprint.

Abstract: A combination composed from a form standard and a CSP is attached to flex circuitry. Solder paste is applied to first selected locations on the flex circuitry and adhesive is applied to second selected locations on the flex circuitry. The flex circuitry and the combination of the form standard and CSP are brought into proximity with each other. During solder reflow operation, a force is applied that tends to bring the combination and flex circuitry closer together. As the heat of solder reflow melts the contacts of the CSP, the combination collapses toward the flex circuitry displacing the adhesive as the solder paste and contacts merge into solder joints. In a preferred embodiment, the form standard will be devised of heat transference material, a metal, for example, such as copper would be preferred, to improve thermal performance. In other embodiments, the methods of the invention may be used to attach a CSP without a form standard to flex circuitry.

Abstract: The present invention stacks chip scale-packaged integrated circuits (CSPs) into low profile modules that conserve PWB or other board surface area. Low profile contacts are created by any of a variety of methods and materials. A consolidated low profile contact structure and technique is provided for use in alternative embodiments of the present invention. Multiple numbers of CSPs may be stacked in accordance with the present invention. The CSPs employed in stacked modules devised in accordance with the present invention are connected with flex circuitry that exhibit one or two or more conductive layers.

Abstract: Abstract of the Disclosure One or more connectors are mounted to a module having one or more integrated circuits. In one embodiment, multiple ICs are stacked and interconnected to form a high-density module. The connectors are preferably mounted above the top IC of the module, but may be mounted at other locations. Electrical or fiber-optic cables may be plugged into the connectors. Other devices may be plugged into the connectors. Other embodiments may have one or more connectors mounted to flexible circuitry. Schemes are disclosed to employ various embodiments for test or operational signaling purposes.

Abstract: Abstract of the Disclosure Integrated circuits (ICs) are stacked into modules that conserve PCB or other board surface area. The modules provide for lower capacitance memory signaling systems and methods for connecting stacked CSPs in a serial cascade arrangement. In one preferred embodiment, on-die terminations are used selectively to terminate a cascaded series of conductive paths. In another preferred embodiment, a form standard provides a physical form that allows many of the varying package sizes found in a broad family of CSP packages to be used to advantage while employing a standard connective flex circuitry design.

Abstract: A termination circuit changes impedance to match a transmission line impedance. The change is made after a signal driver applies a signal through the termination circuit to the transmission line but before a signal reflection returns from an end of the transmission line.

Abstract: The present invention stacks integrated circuits (ICs) into modules that conserve PWB or other board surface area. In another aspect, the invention provides a lower capacitance memory expansion addressing system and method and preferably with the CSP stacked modules provided herein. In a preferred embodiment in accordance with the invention, a form standard provides a physical form that allows many of the varying package sizes found in the broad family of CSP packages to be used to advantage while employing a standard connective flex circuitry design. In a preferred embodiment, the form standard will be devised of heat transference material such as copper to improve thermal performance. In an alternative embodiment, the form standard may include a heat spreader portion with mounting feet. In a preferred embodiment of the memory addressing system, a high speed switching system selects a data line associated with each level of a stacked module to reduce the loading effect upon data signals in memory access.

Abstract: The present invention stacks chip scale-packaged integrated circuits (CSPs) into modules that conserve PWB or other board surface area. In another aspect, the invention provides a lower capacitance memory expansion addressing system and method and preferably with the CSP stacked modules provided herein. In a preferred embodiment in accordance with the invention, a form standard is disposed between the flex circuitry and the IC package over which a portion of the flex circuitry is laid. In a preferred embodiment, the form standard will be devised of heat transference material such as copper to improve thermal performance. In a preferred embodiment, a high speed switching system selects a data line associated with each level of a stacked module to reduce the loading effect upon data signals in memory access. This favorably changes the impedance characteristics exhibited by a DIMM board populated with stacked modules.

Abstract: The present invention stacks packaged integrated circuits into modules that conserve PWB or other board surface area. The invention provides techniques and structures for aggregating chip scale-packaged integrated circuits (CSPs) or leaded packages with other CSPs or with monolithic or stacked leaded packages into modules that conserve PWB or other board surface area. The present invention can be used to advantage with CSP or leaded packages of a variety of sizes and configurations ranging from larger packaged base elements having many dozens of contacts to smaller packages such as, for example, die-sized packages such as DSBGA. In a preferred embodiment devised in accordance with the present invention, a base element IC and a support element IC are aggregated through a flex circuit having at least two conductive layers that are patterned to selectively connect the two IC elements.

Abstract: The present invention provides a method and apparatus for fabricating densely stacked ball-grid-array packages into a three-dimensional multi-package array. Integrated circuit packages are stacked on one another to form a module. Lead carriers provide an external point of electrical connection to buried package leads. Lead carriers are formed with apertures that partially surround each lead and electrically and thermally couple conductive elements or traces in the lead carrier to each package lead. Optionally thin layers of thermally conductive adhesive located between the lead carrier and adjacent packages facilitates the transfer of heat between packages and to the lead carrier. Lead carriers may be formed of custom flexible circuits having multiple layers of conductive material separated by a substrate to provide accurate impedance control and providing high density signal trace routing and ball-grid array connection to a printed wiring board.