Patent Application
20060221590
The present disclosure relates to a system, apparatus, and method for coupling a card mezzanine card to a circuit board.
In computer systems, computer component cards may be connected to a single base or carrier board that plugs into a computer bus or data path. The component cards may be stacked on the base or carrier board and are commonly referred to as mezzanine cards. An Advanced Mezzanine Card (AMC) is a high-speed, hot-swappable mezzanine card that is compatible with, but not limited to, use with Advanced Telecommunications Computing Architecture (ATCA) carriers. The AMC standard is designed to enhance modularity and high-speed serial connectivity for ATCA and other platforms. AMC cards may use high speed interconnect standards such as PCI Express, which provides a high speed serial connection.
The hot-swappable nature of AMC cards may provide useful functionality. In many applications, however, hot-swappability is not an important or even necessary feature. Specialized connectors are required to facilitate the hot-swappable characteristic of AMC cards. Frequently support structures, such as rails, are also included to enable and/or facilitate the hot-swappable feature of AMC cards. Connectors and support structures necessary to allow hot-swappability of AMC card may add to the cost of utilizing AMC cards. Furthermore, the hot-swappable AMC connectors provide a standardized spacing between stacked AMC cards and/or between an AMC card and a carrier board. The standard spacing of the AMC connectors dictates the maximum height of components that can be included on an AMC card and/or airflow pathways around the AMC card and/or components on and AMC card.
Features and advantages of the claimed subject matter will be apparent from the following detailed description of embodiments consistent therewith, which description should be considered with reference to the accompanying drawings, wherein:
Although the following Detailed Description will proceed with reference being made to illustrative embodiments, many alternatives, modifications, and variations thereof will be apparent to those skilled in the art. Accordingly, it is intended that the claimed subject matter be viewed broadly.
With reference to
Turning to
In an embodiment herein, the circuit board 104a may be configured to be electrically coupled to an advanced mezzanine card (AMC) complying with and/or compatible with PCI Industrial Computer Manufacturers Group (PICMG), Advanced Mezzanine Card (AMC) Base Specification, PICMG AMC.0 revision 1.0, published Jan. 3, 2005 (the “AMC Specification”). As such, the connector footprint 202 and the electrical contacts 204 may be configured to be electrically coupled to an AMC connector, such as basic B or AB connector or an extended B+ or A+B+ connector. According to other embodiments, the circuit board may be configured to be coupled to various cards in addition to cards complying with and/or compatible with the AMC Specification. The number of electrical contacts and the arrangement of the electrical contacts may be provided to comply with the appropriate technical specifications for the circuit board and/or for the card.
The circuit board 104a depicted in
Turning to
In an embodiment, the connector portion 302 of the card 108a may include a plurality of conductive traces 304, generally. The conductive traces 304 may include, for example, metallic regions on and/or exposed to the surface of the card 108a. The conductive traces 304 may be capable of providing electrical connection between any components and/or circuits disposed on and/or associated with the card 108a and a circuit board and/or computer system. The size, number, and location of the conductive traces may be provided in accordance with the relevant technical specification for the card 108a. The illustrated embodiment depicts a plurality of conductive traces disposed on one side of the card. Consistent with a further embodiment, the card may be provided having at least one conductive trace on one and/or both sides of the card.
According to an embodiment herein the card may be a card complying with and/or compatible with the AMC Specification. In such an embodiment the conductive traces in the connector portion of the card may be provided having a configuration suitable for use with a basic B/AB connector configuration and/or an extended B+/A+B+ connector configuration, as defined by the AMC Specification. Consistent with the present disclosure, the card may comply with a technical specification other than the AMC Specification. In such embodiments the conductive traces may be provided having various other configurations complying with technical standards other than the AMC Specification.
Turning to
With reference to
In one embodiment, at least a portion of the first plurality of electrical contacts 405 on the second side of the wiring board may correspond to conductive traces 304 on at least one side of the card 108 facing the circuit board 104. The first plurality of electrical contacts 405 on the second side of the wiring board 402 corresponding to the conductive traces 304 facing the circuit board may be capable of being electrically coupled to the conductive traces 304 of the card. In this manner, at least a portion of the electrical contacts, e.g. 204, included in the connector footprint 202 of the circuit board 104 may be electrically coupled to at least a portion of the conductive traces 304 included on the card 108.
In one embodiment, the first wiring board 402 may be electrically coupled to the circuit board 104 and/or the card 108 via anisotropic conductive layers 404, 406. In one specific embodiment, the anisotropic conductive layers 404, 406 may include an anisotropic conductive polymer material or film. The anisotropic conductive polymer layers 404, 406 may include anisotropic conductive elastomer, adhesive, film, etc. capable of conducting an electric current through the thickness of the layer with little or no conduction along the length and/or width of the layer. The anisotropic conductive layer may conduct current between corresponding contacts of the circuit board and wiring board and between corresponding contacts of the wiring board and card with little or no conduction to offset contacts
At least a portion of the plurality of electrical contacts 204 included in the connector footprint 202 of the circuit board 104 may be electrically coupled to one or more conductive traces disposed on the card 108 facing away from the circuit board 104. According to one such embodiment, a second wiring board 408 may be provided having a plurality of electrical contacts (not shown) that are capable of being electrically coupled to one or more of the conductive traces disposed on the card 108 facing away from the circuit board 104. The electrical contacts of the second wiring board 408 capable of being electrically coupled to the conductive traces facing away from the circuit board 104 may be electrically coupled to the contacts 204 included in the connector footprint 202 of the circuit board 104.
In an embodiment herein, at least a portion of the electrical contacts 403 included on the first wiring board 402, corresponding to the electrical contacts 204 of the connector footprint 202 of the circuit board 104, may be coupled to a second plurality of electrical contacts 407 on the second side of the first wiring board 402. As depicted, at least a portion of the electrical contacts 403 on the first side of the first wiring board 402 may be coupled to the second plurality of electrical contacts 407 on the second side of the first wiring board 403 via a plurality of conductive pathways 409 disposed on the first wiring board 402, and/or a plurality of through-board conductive pathways. The conductive pathways 409 may be disposed on the first and/or the second side of the first wiring board 402.
A third wiring board 410 may include a plurality of electrical contacts on the first side of the third wiring board 410. At least a portion of the plurality of electrical contacts on the first side of the third wiring board 410 may be capable of being electrically coupled to the second plurality of electrical contacts 407 on the second side of the first wiring board 402. Similar to the first wiring board 404, the third wiring board 410 may include a plurality of electrical contacts on a second side of the third wiring board that are electrically coupled to at least a portion of the plurality of electrical contacts on the first side of the third wiring board 410. In one embodiment, at least a portion of the plurality of electrical contacts on the first side of the third wiring board 410 may be electrically coupled to at least a portion of the plurality of electrical contacts on the second side of the third wiring board 410 via conductive pathways and/or through-board conductors disposed on and/or associated with the third wiring board 410. Accordingly, at least a portion of the plurality of electrical contacts on the second side of the third wiring board 410 may be capable of being electrically coupled to at least a portion of the second plurality of electrical contacts 407 on the second side of the first wiring board 402 via the plurality of electrical contacts on the first side of the third wiring board 410.
At least a portion of the plurality of electrical contacts on a second side of the third wiring board 410 that may be capable of being electrically coupled to the second plurality of electrical contacts on the second wiring board 408. As mentioned above, at least a portion of the plurality of electrical contacts on the second side of the third wiring board 410 may be electrically coupled to a plurality of electrical contacts on the first side of the third wiring board 410. Accordingly, the second plurality of electrical contacts on the second wiring board 408 may be capable of being coupled to the plurality of electrical contacts on the first side of the third wiring board 410 via the electrical contacts on the second side of the third wiring board 410.
At least a portion of the first plurality of electrical contacts of the second wiring board 408 may be capable of being coupled to conductive traces disposed on the card 108 facing away from the circuit board 104 may be electrically coupled to a second plurality of electrical contacts on the second wiring board located at least partially outside of the perimeter of the card 108. According to one embodiment, the first plurality of electrical contacts of the second wiring board may be coupled to the second plurality of electrical contacts of the second wiring board by conductive pathways on the second wiring board, similar to the conductive pathways included on the first wiring board.
Consistent with the foregoing, one or more conductive traces on the card 108 facing away from the circuit board 104 may be capable of being coupled to one or more contacts 204 included in the connector footprint 202 included on the circuit board 104. At least a portion of the first plurality of electrical contacts of the second wiring board 408 may be capable of being coupled to conductive traces disposed on the card 108 facing away from the circuit board 104. The first plurality of electrical contacts of the second wiring board 408 may be coupled to a second plurality of electrical contacts on the wiring board 408. At least a portion of the second plurality of electrical contacts on the second wiring board 408 may be capable of being coupled to a plurality of electrical contacts on a second side of a third wiring board 410. The plurality of electrical contacts on the second side of the third wiring board 410 may be coupled to a plurality of contacts on the first side of the third wiring board 410. At least a portion of a second plurality of electrical contacts 407 on a second side of the first wiring board 402 may be capable of being coupled to at least a portion of the electrical contacts on the first side of the third wiring board 410. The second plurality of electrical contacts 407 on the second side of the first wiring board 402 may be coupled to a plurality of electrical contacts 403 on the first side of the first wiring board 402. At least a portion of the electrical contacts 403 on the first side of the first wiring board 402 may be capable of being coupled to one or more electrical contacts 204 in a connector footprint 202 included on the circuit board 104. In the foregoing manner, at least a portion of the electrical contacts 204 of the connector footprint 202 on the circuit board 104 may be capable of being coupled to one or more of the conductive traces on the card 108 facing away from the circuit board 104.
In the illustrated embodiment of
As previously mentioned, the first wiring board 402 may be electrically coupled to each of the circuit board 104 and the card 108 via respective anisotropic conductive layers 404, 406. In a similar manner, the first wiring board 402 may also be electrically coupled to the third wiring board 410 via the second anisotropic conductive layer 406. A third anisotropic conductive layer 412 may be disposed overlying at least a portion of the card 108 and the third wiring board 410. The third anisotropic conductive layer 412 may, accordingly, electrically coupled the third wiring board 410 and the second wiring board 408. The third anisotropic conductive layer 412 may also electrically couple the second wiring board 408 and the card 108.
According to one aspect, the separation between the card 108 and the circuit board 104 may be varied by varying the thickness of the first wiring board 402. In further embodiments, a plurality of wiring boards may be provided in a stacked assembly and disposed between the card and the circuit board. The stacked assembly of wiring boards may provide a cumulative thickness and a corresponding separation between the card and the circuit board. The separation between the card and the circuit board may be provided, for example, based on component heights on the card and/or airflow pathways between the card and/or components on the card and adjacent features. Similar to the illustrated assembly of the circuit board 104, the first wiring board 402, and the card 108, individual wiring boards in a stacked wiring board assembly disposed between the circuit board and the card may be electrically coupled to one another using one or more layers of anisotropic conductive material. Adjacent surfaces of adjacent wiring boards in a stacked assembly may include corresponding electrical contacts. The anisotropic conductive material may be disposed between adjacent wiring boards of the stacked configuration. The layers of anisotropic conductive material may provide an electrical pathway between the corresponding electrical contacts of the adjacent wiring boards.
Consistent with the illustrated embodiment, the stacked arrangement of the circuit board 104, first wiring board 402, card 108, third wiring board 410, and second wiring board 408 may be assembled using fasteners 414, 416. In an embodiment herein, the fasteners 414, 416 may be screws. Various alternative mechanical fasteners may also be employed for assembling the circuit board/card assembly 400. In one embodiment, the circuit board 104, first wiring board 402, second siring board 408, and third wiring board 410 may each include holes for receiving the fasteners 414, 416 therethrough. In addition to receiving the fasteners 414, 416, the holes may also index the circuit board 104 and wiring boards 402, 408, 410 allowing facile alignment of the various corresponding electrical contacts. According to one aspect, the fasteners 414, 416 may provide sufficient compression of the circuit board 104 and wiring boards 402, 408, 410 to achieve electrical coupling of corresponding electrical contacts. An embodiment consistent with the preceding description may provide facile assembly of a circuit board, card, and associated wiring boards.
According to one embodiment, the card 108 may generally be maintained in position by the compressive and/or spring force of the second wiring board 408 bearing against the card 108. In such an embodiment, the card 108 may generally be clamped between the first wiring board 402 and the second wiring board 408. The clamp force of the second wiring board 408 and the first wiring board 402 may be sufficient to maintain the card 108 electrically coupled to the first wiring board 402 and the second wiring board 408. In a further embodiment, the clamping force provided by the second wiring board 408 may be sufficient to physically retain the card 108 in position between the second wiring board 408 and the first wiring board 402. In another embodiment, at least one fastener, such as a screw, may pass through an opening in the card. Such a mechanical fastener may secure the card in position and/or further ensure electrical coupling between conductive traces on the card and corresponding electrical contacts on the first and/or second wiring boards.
According to another aspect, the circuit board/card assembly 400 may include additional mechanical fasteners 418, 420 which may couple the card 108 to the circuit board 104. The fasteners 418, 420 may assist in maintaining the card 108 in position sandwiched between the first wiring board 402 and the second wiring board 408. Furthermore, in part, the fasteners 418, 420 may index the card 108 relative to the circuit board 104 and/or one or more of the wiring boards 402, 408, 410. In this manner, the fasteners 418, 420 may maintain the conductive traces of the card 108 in position relative to the corresponding electrical contacts of the first and/or second wiring boards 402, 408.
Spacers 422, 424 may be disposed between the card 108 and the circuit board 104. The spacers 422, 424 may reduce and/or eliminate deflection of the card 108 toward the circuit board 104. Deflection of the card 108 may result from mechanical loads applied to the card 108. Deflection of the card 108 as a result of mechanical loads experienced by the card 108 may result in movement of the card 108 relative to the circuit board 104 and/or relative to the wiring boards 402, 408, 410 and or breakage or damage of the card 108. Movement of the card 108 relative to the circuit board 104 and/or relative to the wiring boards 402, 408, 410 may result in a loss of electrical coupling between the card and the circuit board 104 and/or one of the wiring boards 402, 408, 410. Employing spacers 422, 424 to reduce and/or eliminate deflection of the card 108 towards and/or away from the circuit board 104 may facilitate maintaining electrical connection between the card 108 and the circuit board 104 and/or one or more of the wiring boards 402, 408, 410. Additionally, employing spacers 422, 424 to reduce and/or eliminate deflection of the card 108 may reduce and/or eliminate associated damage to the card 108.
Numerous anisotropic conductive materials, often call Z-axis materials, are known. As shown in
Referring to
According to an alternative embodiment, rather than being disposed in a common frame, a system consistent with the present disclosure may include a plurality of chassis that may be individually hardwired to one another. One or more of the plurality of chassis may include at least one circuit board coupled to at least one card consistent with any embodiment described herein. Additionally, each of the plurality of chassis may be powered by an individual power supply and/or may be separately powered by a common power supply. Such a system may, therefore, provide a greater freedom in the physical arrangement and interrelation of the plurality of chassis.
Consistent with the foregoing, a card may be electrically and/or physically coupled to a circuit board without the use of a dedicated connector. In one specific embodiment, a hot-swappable card, such as a card complying with and/or compatible with the AMC Specification, may be coupled to a circuit board in a non-hot-swappable manner, thereby eliminating the need and/or use of an AMC connector. While the use of an AMC connector may be eliminated consistent with the present disclosure, a circuit board configured for use with a card complying with and/or compatible with the AMC Specification may be employed without modifying the circuit board from a standard connector footprint. Eliminating the use of an AMC connector may decrease the cost of incorporating the card onto the circuit board. Furthermore, by eliminating the AMC connector greater freedom in placement of the card relative to the circuit board may be realized. For example, the spacing of the card relative to the circuit board may be customized without being restricted to positioning dictated by a standard AMC connector. Accordingly, it may be possible to employ greater height components on a card than would be possible using a standard AMC connector. Similarly, airflow passages around the card may be adjusted and/or adapted to specific needs without consideration of the card placement relative to the circuit board dictated by standard AMC connectors.
The terms and expressions which have been employed herein are used as terms of description and not of limitation, and there is no intention, in the use of such terms and expressions, of excluding any equivalents of the features shown and described (or portions thereof), and it is recognized that various modifications are possible within the scope of the claims. Other modifications, variations, and alternatives are also possible. Accordingly, the claims are intended to cover all such equivalents.
