Patent Publication Number: US-8113863-B2

Title: Socket connector having a thermally conductive insert

Description:
BACKGROUND OF THE INVENTION 
     The subject matter herein relates generally to socket connectors, and more particularly, thermal management of socket connectors. 
     Computers and servers may use numerous types of electronic modules, such as processor and memory modules (e.g. Dynamic Random Access Memory (DRAM), Synchronous Dynamic Random Access Memory (SDRAM), or Extended Data Out Random Access Memory (EDO RAM), and the like). The memory modules are produced in a number of formats such as, for example, Single In-line Memory Modules (SIMM&#39;s), or the newer Dual In-line Memory Modules (DIMM&#39;s), Small Outline DIMM&#39;s (SODIMM&#39;s), and Fully Buffered DIMM&#39;s. Typically, the electronic modules are installed in one or more multi-pin socket connectors mounted on a system board or motherboard. Each electronic module has a card edge that provides an interface generally between two opposite rows of contacts in the socket connector. 
     There is an ongoing trend toward smaller electronic packages. The space provided for electronic modules and socket connectors is limited. Moreover, the amount of electrical power consumed by electronic modules, and thus the amount of electrical power carried by the socket connectors, is increasing. Accordingly, more of the contacts of the socket connectors are being used to carry electrical power. The contacts carrying the electrical power generate heat. Additionally, the components held by the electronic modules generate heat. Problems arise in attempting to dissipate the heat generated by the contacts of the socket connector as well as by the electronic modules themselves. Typically, heat sinks are coupled to one or both sides of the electronic modules above the socket connectors. The heat sinks extend outward from the electronic modules, taking up room around the electronic modules. The trend toward smaller electronic packages tends to reduce the amount of space around the electronic modules by populating the space with other socket connectors and corresponding electronic modules, or with other components mounted to the motherboard or as part of the system in general. 
     There is a need for a device that improves heat dissipation from electronic modules without increasing overall package size. 
     BRIEF DESCRIPTION OF THE INVENTION 
     In one embodiment, a socket connector is provided that includes a housing having a mating end and a mounting end. The housing has a receptacle at the mating end configured to receive an electronic module therein. The mounting end of the housing is configured to be mounted to a circuit board. Contacts are held by the housing. The contacts have mating ends exposed within the receptacle for mating with the electronic module. The contacts having mounting ends extending from the housing for terminating to the circuit board. A thermally conductive insert is held by the housing and is configured to be in thermal engagement with the circuit board and the insert has a module engagement interface configured to be in thermal engagement with the electronic module such that the insert transfers heat from the electronic module to the circuit board. 
     In another embodiment, a socket connector is provided including a housing mountable to a host circuit board holding contacts mateable to an electronic module configured to be coupled to the housing. The electronic module includes a circuit board with an edge of the circuit board being received in the housing. A thermally conductive insert is held by the housing in thermal engagement with the electronic module. The insert extends from the housing and is configured to be coupled to the host circuit board. The insert is configured to dissipate heat from the electronic module to the host circuit board. 
     In a further embodiment, a socket connector is provided that includes a housing having a mating end and a mounting end. The housing has a receptacle at the mating end configured to receive an electronic module therein. The mounting end of the housing is configured to be mounted to a circuit board. Contacts are held by the housing for mating with the electronic module. A thermally conductive insert is held by the housing. The insert is configured to be in thermal engagement with the electronic module and with the circuit board to transfer heat from the electronic module to the circuit board. A spring clip is coupled to the housing. The spring clip is configured to engage the electronic module to bias the electronic module against the insert. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side perspective view of a socket connector formed in accordance with an exemplary embodiment. 
         FIG. 2  is a bottom perspective view of the socket connector shown in  FIG. 1 . 
         FIG. 3  is a cross-sectional view of the socket connector shown in  FIG. 1 . 
         FIG. 4  is a cross-sectional view of an alternative socket connector. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  is a side perspective view of a socket connector  10  formed in accordance with an exemplary embodiment. The socket connector  10  is mounted to a circuit board  12 . An electronic module  14  is coupled to the socket connector  10 . The socket connector  10  interconnects the electronic module  14  with the circuit board  12 . In the illustrative embodiment, the circuit board  12  represents a host board or a motherboard forming part of an electrical system or device, such as a computer, a server, a network switch, and the like. The electronic module  14  represents a memory module and the socket connector  10  represents a Dual In-line Memory Module (DIMM) socket, however, other types of electronic modules and/or socket connectors may be provided in alternative embodiments. 
     The electronic module  14  includes a circuit board  16  that is mated with the socket connector  10 . For example, an edge of the circuit board  16  is plugged into the socket connector  10 . Memory devices  18  are mounted to one or both sides of the circuit board  16 . Optionally, the memory devices  18  may be integrated circuit (IC) components, such as microchips or microprocessors, mounted to the circuit board  16 . The electronic module  14  includes a mating end  20  and an outer end  22  opposite to the mating end  20 . The mating end  20  is loaded into the socket connector  10  such that the circuit board  16  is perpendicular to the circuit board  12 . Alternatively, the electronic module  14  may be coupled to a different type of socket connector such that the circuit board  16  is parallel to, and spaced apart from, the circuit board  12 . Other configurations are possible as well that orient the electronic module at an angle other than perpendicular or parallel to the circuit board  16 . 
     The socket connector  10  includes a housing  24  mounted to the circuit board  12 . The housing  24  includes a mating end  26  and a mounting end  28 . The mounting end  28  rests on the circuit board  12 . A receptacle  30  is provided at the mating end  26  to receive the memory device  18 . Optionally, the receptacle  30  may constitute a card edge slot. In an exemplary embodiment, the mating end  26  and the mounting end  28  are opposite to one another. Alternatively, the mating end  26  may be angled with respect to the mounting end  28 , such as perpendicular to the mounting end  28  defining a right angle socket connector or at other angles, to receive the electronic module  14 . 
     Ejectors  32  are provided at opposite ends of the housing  24 . The ejectors  32  hold the electronic module  14  within the socket connector  10 . The ejectors  32  are used to eject the electronic module  14  from the receptacle  30 . In an exemplary embodiment, each ejector  32  includes a tab  34  extending therefrom. 
     In an exemplary embodiment, the socket connector  10  includes a spring clip  36  coupled to the housing  24 . Optionally, the spring clip  36  may be coupled to the ejectors  32 . The spring clip  36  extends along the outer end  22  of the electronic module  14 . The spring clip  36  is biased against the electronic module  14  to force the electronic module  14  into the receptacle  30 . Optionally, the spring clip  36  may be bowed such that a central portion of the spring clip  36  engages electronic module  14 . The spring clip  36  may be flexed when coupled to the housing  24  and the electronic module  14  to provide a spring force against the electronic module  14 . The spring clip  36  may have alternative shapes in alternative embodiments. The spring clip  36  may engage different portions of the electronic module  14  in alternative embodiments. The spring clip  36  may be coupled to different portions of the housing  24  or other structures, such as the circuit board  12 , in alternative embodiments. Multiple spring clips may be provided. Other types of biasing mechanisms, generally referred to as spring clips, may be used in alternative embodiments to provide a normal force on the electronic module  14 . 
       FIG. 2  is a bottom perspective view of the socket connector  10  with the electronic module  14  coupled thereto. The mounting end  28  of the housing  24  is illustrated. The socket connector  10  includes a plurality of contacts  40  held by the housing  24  that extend from the mounting end  28  for mating with the circuit board  12  (shown in  FIG. 1 ). For example, the contacts  40  may be through hole mounted to corresponding vias in the circuit board  12 . Alternatively, the contacts  40  may be surfaced mounted to pads on the circuit board  12  or may be a compliant pin press fit. In the illustrative embodiment, the contacts  40  are arranged in two parallel rows. 
     The socket connector  10  includes mounting clips  42  that hold the housing  24  to the circuit board  12 . The mounting clips  42  may be used to orient the socket connector  10  in proper position with respect to the circuit board  12 . Optionally, the mounting clips  42  may hold the housing  24  in position on the circuit board  12  during soldering of the socket connector  10  to the circuit board  12 . 
     The socket connector  10  includes a seating plane in the form of an insert  44  extending from the mounting end  28  of the housing  24 . The insert  44  is arranged between the rows of contacts  40 . The insert  44  is used to help seat the socket connector  10  onto the circuit board  12 . Optionally, the circuit board  12  may include a channel that receives the insert  44  therein to help stabilize the socket connector  10  with respect to the circuit board  12 . In an exemplary embodiment, the insert  44  is thermally conductive and thermally engages the circuit board  12  to dissipate heat from the socket connector  10  to the circuit board  12 . The insert  44  is also in thermal engagement with the electronic module  14  to dissipate heat from the electronic module  14  to the circuit board  12 . The insert  44  defines a thermally conductive path from the electronic module  14  to the circuit board  12 . In an exemplary embodiment, the insert  44  may be manufactured from a metal material. The insert  44  may be soldered to the circuit board  12  during a soldering operation, or may otherwise thermally engage the circuit board  12 , such as by a thermal paste. The insert  44  may be manufactured from other highly thermally conductive materials such as plated plastic, thermally conductive plastic or other thermally conductive compounds with good thermal conductivity properties. 
       FIG. 3  is a cross-sectional view of the socket connector  10  with the electronic module  14  coupled thereto. The socket connector  10  is mounted to the circuit board  12 , which is represented schematically in  FIG. 3 . The mounting end  28  of the housing  24  rests upon the circuit board  12 . The mating end  26  is opposite the mounting end  28  and is generally parallel to the mounting end  28 . The electronic module  14  is loaded into the receptacle  30  through the mating end  26  of the housing  24 . 
     The contacts  40  are held by the housing  24  and extend from the mounting end  28  into the circuit board  12 . The contacts  40  extend between mating ends  50  and mounting ends  52 . The contacts  40  are held by the housing  24  such that the mounting ends  52  extend from the housing  24  for electrical connection with the circuit board  12 . The mating ends  50  are exposed within the receptacle  30  for mating with the electronic module  14 . In an exemplary embodiment, the contacts  40  are arranged in two generally parallel rows configured to engage both sides of the electronic module  14 . The mating portions of the contacts  40  proximate to the mating ends  50  are held against electronic module  14 , such as by a spring force. For example, the contacts  40  may be deflected outward during mating with the electronic module  14  such that the contacts  40  are biased against the electronic module  14 . The portions of the contacts  40  extending from the mounting end  28 , sometimes referred to as contact tails, may be staggered along the centerline of each row. Such configuration may accommodate tighter spacing between the contacts  40 . 
     The contacts  40  may be power contacts transmitting power across the mating the face, signal contacts transmitting data across the mating face, or ground contacts grounding the socket connector  10  to circuit board  12 . In an exemplary embodiment, the socket connector  10  includes all three types of contacts. 
     The housing  24  includes a cavity  54  that is open at the mounting end  28  and that receives the insert  44 . Optionally, the insert  44  may be loaded into the cavity  54  through the mounting end  28  and held in the cavity  54  by a press fit. Alternatively, the body of the housing  24  may be molded around a portion of the insert  44  such that a portion of the insert  44  is surrounded by the housing  24  and another portion of the insert  44  extends from the housing  24 . The insert  44  is received within the circuit board  12  and is in thermal engagement with a portion of the circuit board  12 . Optionally, the circuit board  12  may include a heat sink or one or more layers that define a heat sink, wherein heat transmitted by the insert  44  is dissipated from the insert  44  by the heat sink or the layers of the circuit board  12  defining a heat sink. The insert  44  includes a module engagement interface  56  that is in thermal engagement with the electronic module  14 . The module engagement interface  56  may be planar and defined by the top of the insert  44 . Alternatively, the module engagement interface  56  may be defined by more than one surface of the insert  44 , such as the top and portions of the sides of the insert  44 . 
     The insert  44  is manufactured from a thermally conductive material, such as a metal material like copper or bronze. The insert  44  may be manufactured from other types of materials that are thermally conductive. The insert  44  provides a direct link between electronic module  14  and circuit board  12  to dissipate heat from the electronic module  14  through the socket connector  10  and into the circuit board  12 . For example, the insert  44  may be directly physically engaged to the electronic module  14  and to the circuit board  12 . In this manner, the insert  44  defines a heat sink transferring heat away from the electronic module  14 . The circuit board  12  provides a large area for dissipating the heat generated by the electronic module  14 . 
     The socket connector  10  includes a contact reception cavity  60  between the contacts  40 . The contact reception cavity  60  may be part of the receptacle  30 . The edge of the electronic module  14  is received within the contact reception cavity  60 . The contacts  40  engage contact pads on the outer sides of the edge of the electronic module  14  within the contact reception cavity  60 . The contact reception cavity  60  is open to the cavity  54 . At least a portion of the insert  44  is received within the contact reception cavity  60  between the two rows of contacts  40 . 
     The socket connector  10  has an outer perimeter defining a footprint on the circuit board  12 . Optionally, the outer perimeter may be the largest at the mounting end  28 . In an exemplary embodiment, the insert  44  is positioned entirely within the outer perimeter of the socket connector  10  such that the overall footprint of the socket connector  10  is not increased by the insert  44 . 
     When the electronic module  14  engages the insert  44 , heat transfer is able to occur across the interface. Optionally, a thermally conductive paste  58  or other thermally conductive layer or material may be provided between the electronic module  14  and the module engagement interface  56  of the insert  44 . The electronic module  14  may be specifically designed to transfer heat to the mating end  20  of the electronic module  14 . For example, the electronic module  14  may include an internal heat sink  62 , shown in phantom in  FIG. 3 , in the form of thermally conductive traces routed through the electronic module  14  to the mating end  20 . Other configurations for the electronic module  14  are possible in alternative embodiments that transfer heat to the mating end  20 . 
     In an exemplary embodiment, the spring clip  36  is provided to hold the electronic module  14  in the receptacle  30 . The spring clip  36  generally forces the electronic module  14  toward the insert  44 . For example, the spring clip  36  provides a normal force on the electronic module  14  in the direction of the insert  44 , as shown by the arrow A. The pressure holding the electronic module  14  against the module engagement interface  56  provides good thermal contact between the electronic module  14  and the insert  44 . 
     The mounting clip  42  is illustrated in  FIG. 3 . The mounting clip  42  is received within the circuit board  12  to hold the socket connector  10  in position with respect to the circuit board  12 . In an exemplary embodiment, the mounting clip  42  extends further from the mounting end  28  of the housing  24  than the contacts  40  and/or the insert  44 . The mounting clip  42  may thus be used to locate the socket connector  10  with respect to the circuit board  12  prior to loading the contacts  40  and/or the insert  44  into the corresponding vias and channel, respectively. 
       FIG. 4  is a cross-sectional view of an alternative socket connector  110 . The socket connector  110  is mounted to a circuit board  112 . An electronic module  114  is received within the socket connector  110 . The socket connector  110  represents a right angled socket connector having a mating end  115  oriented perpendicular to a mounting end  116 . The electronic module  114  is loaded into the socket connector  110  in a direction parallel to the circuit board  112 . Alternatively, the electronic module  114  may be loaded into the socket connector  110  at an angle that is non-parallel to the circuit board and then is rotated to an orientation that is parallel to the circuit board  112 . The electronic module  114  is oriented generally parallel to the circuit board  112  and is spaced apart from the circuit board  112 . Such configuration reduces the overall height of the system and is suited for applications in which a low-profile connector is utilized, such as for example, a notebook computer application. 
     The socket connector  110  includes upper contacts  118  and lower contacts  120  that engage an upper side and lower side, respectively of the electronic module  114 . The upper and lower contacts  118 ,  120  are electrically connected to the circuit board  112 . In the illustrated embodiment, the upper and lower contacts  118 ,  120  are surface mounted to the circuit board  112 . 
     The socket connector  110  includes a thermally conductive insert  122 . The insert  122  extends from the mounting end  116  and engages the circuit board  112 . Optionally, the insert  122  extends at least partially through the circuit board  112 . The insert  122  is in thermal communication with the circuit board  112  to transfer heat from the electronic module  114  into the circuit board  112 . The insert  122  includes a module engagement interface  124  that engages the electronic module  114 . Optionally, the module engagement interface  124  may engage multiple surfaces of the electronic module, such as an end and one or more sides of the electronic module  114 . The insert  122  is in thermal engagement with electronic module  114  such that the insert  122  transfers heat away from the electronic module  114 . The insert  122  provides a direct thermal link between electronic module  114  and the circuit board  112 . In an exemplary embodiment, the insert  122  is manufactured from a thermally conductive material, such as a metal material. The insert  122  defines a heat sink the transfers heat from the electronic module  114  to the circuit board  112 . 
     It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments (and/or aspects thereof) may be used in combination with each other. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Dimensions, types of materials, orientations of the various components, and the number and positions of the various components described herein are intended to define parameters of certain embodiments, and are by no means limiting and are merely exemplary embodiments. Many other embodiments and modifications within the spirit and scope of the claims will be apparent to those of skill in the art upon reviewing the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. Further, the limitations of the following claims are not written in means—plus-function format and are not intended to be interpreted based on 35 U.S.C. §112, sixth paragraph, unless and until such claim limitations expressly use the phrase “means for” followed by a statement of function void of further structure.