Abstract:
A surface mount connector and assembly including the surface mount connector is shown and described. The assembly comprises a substrate and a connector including a carrier, and at least one electrical connecting element having first and second ends, wherein at least a portion of the first end extends through the carrier to electrically adjoin and physically secure the connector to the substrate. A reinforcement medium is disposed about at least a portion of surface mount connector and said substrate.

Description:
TECHINCAL FIELD  
       [0001]     The present invention relates to a connector and, more particularly, to a surface mount connector.  
       BACKGROUND  
       [0002]     Through-hole connectors are traditionally used to provide product connecter headers in many applications. Conventional through-hole connection technology provides increased reliability and robustness and, accordingly, through-hole connectors are traditionally utilized in environments that demand reliability. Among others, the automotive industry, often utilizes through-hole connectors for circuit boards, as the demand for reliability in an automobile is generally high.  
         [0003]     Conventional through-hole attachment techniques typically require a process to attach the connector to the substrate such as, for example and without limitation, a selective wave solder process or a pin and paste process. In addition, as substrates often include multiple layers, the through-hole connector often consumes valuable substrate real estate. This real estate could otherwise be used, for example and without limitation, to provide additional electrical pathways and the like through the substrate and mounting of electrical components on the surface of the opposing side of the substrate  
         [0004]     To help minimize or eliminate the consumption of such real estate; attempts have been made to replace the through-hole connectors with various surface mount connector assemblies. However, many surface mount connector assemblies generally compromise product reliability as they often malfunction due to lost, or otherwise broken, electrical or physical connections between the substrate and the connector. Such malfunctions arise, for example, due to cracks or the like arising between the connector and the substrate. Such malformations are typically the result of a mechanical overstress, or a coefficient of thermal expansion mismatch between the connector and the substrate.  
       SUMMARY  
       [0005]     A surface mount connector and assembly including the surface mount connector is shown and described. The assembly comprises a substrate and a connector including a carrier, and at least one electrical connecting element having first and second ends, wherein at least a portion of the first end extends through the carrier to electrically adjoin and physically secure the connector to the substrate. A reinforcement medium is disposed about at least a portion of the connector and the substrate. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]     Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, wherein:  
         [0007]      FIG. 1  is an isometric view of a surface mount connector assembly mounted on a substrate according to an embodiment of the invention;  
         [0008]      FIG. 2A  is an isometric view of a connection sub-assembly according to an embodiment of the invention;  
         [0009]      FIG. 2B  is an isometric view of a connection sub-assembly according to an embodiment of the invention;  
         [0010]      FIG. 2C  is an isometric view of a connection sub-assembly according to an embodiment of the invention;  
         [0011]      FIG. 3  is a connector assembly according to an embodiment of the invention; and  
         [0012]      FIG. 4  is a partial cross-sectional view of the connector assembly from  FIG. 3  mounted on a substrate according to an embodiment of the invention. 
     
    
     DETAILED DESCRIPTION  
       [0013]     Referring to  FIG. 1 , a surface mount connector assembly is shown generally at  10  according to an embodiment of the present invention. The illustrated system comprises a surface mount connector  11  and a substrate  13 . Surface mount connector  11  includes a connection sub-assembly  12  and is configured to generally attach surface mount connector  11  to substrate  13 . In an embodiment, connection sub-assembly  12  electrically adjoins and mechanically attaches surface mount connector  10  to substrate  13 .  
         [0014]     With reference to  FIGS. 2A-4  connection sub-assembly  12  may include a carrier  14  and at least one connecting element  16 . Among other possibilities, connecting element  16  will be hereinafter referred to as pin  16 , however, one skilled in the art will recognize that other possible connecting elements may be integrated into the system and the invention discussed should not be so limited thereby. For example, connecting element  16  may be a solder ball or the like. It will be appreciated that a shroud  17  or the like may house connection sub-assembly  12  to generally shield connection sub-assembly  12  from externalities including, for example, other elements or the like resident on substrate  13 .  
         [0015]     In an embodiment, carrier  14  includes a proximal side  18  and a distal side  20 , and connecting element  16  includes a first end portion  22  and a second end portion  24 . First end portion  22  of pin  16  may be adjacent to (as shown in  FIG. 2B ) or extend beyond (as shown in  FIG. 2C ) proximal side  18  of carrier  14 . Second portion  24  may extend from distal side  20  of carrier  14 . First end portion  22  may be adapted to attach, electrically or otherwise, pin  16  to substrate  13 . In an embodiment, at least a portion of first end portion  22  of pin  16  may extend through carrier  14  so that carrier  14  forms a common base. Carrier  14  may comprise a ferrous material and form a ferrite block which acts as an inductor to reduce electromagnetic emissions. Moreover, chip capacitors or the like may also be attached to the pin carrier board for additional electromagnetic interference filtering. It will be appreciated, that carrier  14  may comprise other similar materials, and these materials will be readily recognized by one of ordinary skill in the art. It should further be noted, that pins  16  may be arranged and commonly grouped to electrically connect to common portions of substrate  13  (as shown in  FIG. 2B ) or pins  16  may each individually be arranged to connect with individual portions of substrate  13  (as shown in  FIG. 2C ). These and other features will be readily recognized by one of ordinary skill in the art without deviating from the present disclosure.  
         [0016]     In an embodiment, second portion  24  of pin  16  may remain generally unencumbered and, therefore, may be used to attach, electrically or otherwise, substrate  13  to an external element (not shown) through surface mount connector  11  and surface mount connector assembly  10 . Thus, pin  16  may provide an unencumbered attachment means between external element (not shown) and substrate  13 . Also, pin  16  may be generally comprised of conductive material to form an electrical pathway to substrate  13 . These and other similar features of carrier  14  and pin  16  will be recognized by one of skill in the art.  
         [0017]     As shown in  FIG. 1 ,  FIG. 3  and  FIG. 4 , surface mount connector  10  mechanically and electrically mounts to a surface of substrate  13 . In an embodiment, substrate  13  may include at least one connector receiving portion  26  to provide means to mechanically and electrically adjoin substrate  13  with surface mount connector  11  to form surface mount connector assembly  10 . Among other possibilities, connector receiving portion  26  may be a solder bond pad  28  that corresponds to pin  16  of surface mount connector  11 .  
         [0018]     In an embodiment, pin  16  may further include a solder portion  30 , such as a solder ball or the like. Solder portion  30  may be arranged along at least a portion of first end portion  22  of pin  16  such that, upon applying heat or the like, for example, as applied during a reflow process, solder portion  30  provides a bond or the like between pin  16  and solder band pad  28 . It will be appreciated, that structures, other than solder balls and solder bond pads  28  may be used to form the bond between pin  16  and receiving portion  26 . For example, among other possibilities, pin  16  may be stamped, drawn or include a solder bump to provide the connection to connector receiving portion  26  during the reflow process.  
         [0019]     In accordance with the present invention, receiving portion  26  is attached to pin  16 , electrically or otherwise, and provides an electrical pathway to attach an external element (not shown) to substrate  13 . In an embodiment, substrate  13  includes a plurality of conductive traces (not shown) to provide conductive pathways to provide signal transfer between external element, pin  16  and substrate  13 . Among other possibilities, substrate  13  may be a laminate circuit board (as shown in  FIG. 4 ) or any other suitable circuit board material known in the art. Other possibilities will be recognized by one of skill in the art and may be appropriately substituted therefore.  
         [0020]     The traces (not shown) may be comprised of metal or an alloy, however, one skilled in the art will readily recognize substitute substrates or trace materials. It will also be appreciated that other connection elements, other than solder bond pad  28 , may be used to mount surface mount connector  10  to substrate  13  and the present invention should not be limited to solder bond pad  28 .  
         [0021]     With continued reference to the Figures, a reinforcement layer  36  may be applied over at least a portion of surface mount connector  11  and substrate  13 . In accordance with the invention, reinforcement layer  36  further secures the connection between substrate  13  and surface mount connector  10  to provide further stability and reliability to the connection. In an embodiment, reinforcement layer  36  may bond surface mount connector  11  to substrate, to a laminate layer resident on substrate  13  or both. Reinforcement layer  36  may be disposed between a portion of substrate  13  and a portion of connection sub-assembly  12  such that reinforcing layer  36  generally encapsulates at least one of the connections therebetween. Additionally, reinforcement layer  36  may be applied over surface mount connector  10  and substrate  13  such that reinforcement layer  36  is molded thereover.  
         [0022]     Reinforcement layer  36  may comprise a non-conductive polymer to form a polymeric body or the like. Among other possibilities, reinforcement layer  36  comprises an epoxy resin. It will be appreciated that the polymeric body may have a coefficient of thermal expansion to generally match the coefficient of thermal expansion of at least a portion of substrate  13 , pin  16  and/or connection sub-assembly  12 . For example, inorganic filler or the like may be added to the polymer to generally match the coefficient of thermal expansion as described. It will be appreciated, that reinforcement layer  36  may provide added electromagnetic interference filtering and one of ordinary skill in the art will readily recognize the benefits provided therefrom.  
         [0023]     Among other possibilities, reinforcement layer  36  may be applied to the assembly as an underfill layer, an overmold layer or both. With reference to the underfill layer, substrate  13  and sub-assembly  12  are generally spaced apart and define a gap  40  therebetween. The underfill layer may be disposed about at least a portion of gap  40 .  
         [0024]     Referring to  FIG. 3 , a back plate  42  or the like may be provided for attaching substrate  13  thereto. Further, reinforcement layer  36  is illustrated as an overmold material  44  to generally encapsulate surface mount connector  10  and substrate  13 . It will be appreciated that various combinations of the structures herein disclosed may be used to apply surface mount connector  10  to substrate  13  without deviating from the present disclosure provided the assembly includes surface mount connector  10 , substrate  13  and reinforcement layer  36 .  
         [0025]     In an embodiment, and as described hereinabove, reinforcement layer  36  may comprise an underfill layer. Underfill layer may be disposed about at least a portion of gap  40  through an injection process, a capillary process or a no-flow process. Underfill layer may bond with at least one of substrate  13 , laminate thereon and at least a portion of surface mount connector  10 . These and other processes to dispose or apply underfill material as a reinforcing layer  36  will become obvious to one of ordinary skill in the art after considering the present disclosure. It will also be appreciated, that reinforcement layer  36  may be a single layer or multiple layers and the invention should not limited to the disclosed number of layers.  
         [0026]     The invention has been particularly shown and described with reference to the foregoing embodiments, which are merely illustrative of the best modes for carrying out the invention. It should be understood by those skilled in the art that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention without departing from the spirit and scope of the invention as defined in the following claims. It is intended that the following claims define the scope of the invention and that the method and apparatus within the scope of these claims and their equivalents be covered thereby. This description of the invention should be understood to include all novel and non-obvious combinations of elements described herein, and claims may be presented in this or a later application to any novel and non-obvious combination of these elements. Moreover, the foregoing embodiments are illustrative, and no single feature or element is essential to all possible combinations that may be claimed in this or a later application.