Abstract:
An electrical connector ( 1 ) includes an insulative housing ( 2 ), a conductive shield ( 3 ) enclosing the insulative housing and a contact insert ( 4, 4′ ). The contact insert has a number of electrical contacts ( 41 - 48, 41′ - 48′ ) arranged into differential pairs. A first electrical contact of a first differential pair electrically couples with a first electrical contact of a second differential pair to balance an electrical coupling between a second electrical contact of the first differential pair and the first electrical contact of the second differential pair.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to an electrical connector, and particularly to a cross-talk reduced modular jack.  
           [0003]    2. Description of the Related Art  
           [0004]    Cross-talk can be generally described as the unwanted coupling of electrical signals on adjacent signal lines. Such cross-talk may result in portion of an electrical signal on one pair of lines appearing on a separate pair of lines as unwanted noise.  
           [0005]    Cross-talk between different pairs of wires is a source of interference that can cause signal degradation and negatively impact the ability of a communication system to process incoming signals. Cross-talk can also increase error rates and reduce signal strength.  
           [0006]    Problems associated with unwanted cross-talk are becoming even more problematic given the general increase in operating frequencies and data rates of modern communication systems. Additionally, cross-talk can be particularly problematic within electrical connectors, e.g., modular jacks, that contain a plurality of contacts that are generally parallel and spaced closely together-a configuration that may lead to excessive cross-talk even over short lengths.  
           [0007]    The modular jacks are always subject to a variety of industry signal transmission protocols, such as 10 BaseT protocol, 100 BaseT protocol and 1000 BaseT protocol. Modular jacks capable of operating in either 10 BaseT protocol or 100 BaseT protocol (i.e., 10/100 BaseT protocol) are commonplace and some modular jacks are entering the 10/1000 BaseT protocol arena, but the market is driven to modular jacks capable of operating at either 10/100 or 10/1000 BaseT protocol.  
           [0008]    It is well known to all skilled in the pertinent art that different methods of compensation to reduce or eliminate the cross-talk have been successful in both 10/100 BaseT protocol and 10/1000 BaseT protocol. However, the different electrical pairing arrangement of the electrical contacts for compensation between 10/100 BaseT protocol modular jack and 10/1000 BaseT protocol modular jack makes the compensation in a commoned 10/100 and 10/1000 BaseT protocol modular jack much more difficult. Ideal compensation in the 10/100 protocol could result in worse than no compensation performance when the modular jack is called upon to perform in the 10/1000 BaseT protocol, and vice versa.  
           [0009]    Furthermore, conventional modular jacks with cross-talk reduced electrical contacts are always difficult and expensive to manufacture.  
           [0010]    Therefore, an improved electrical connector solving or obviating the aforementioned problems is desired.  
         SUMMARY OF THE INVENTION  
         [0011]    A first object of the present invention is to provide an electrical connector which effectively reduces cross-talk between electrical contacts thereof.  
           [0012]    A second object of the present invention is to provide an economically and manufacturably feasible electrical connector conforming to either 10/100 or 10/1000 BaseT protocol.  
           [0013]    An electrical connector in accordance with the present invention comprises an insulative housing defining a receiving cavity, a conductive shield enclosing the insulative housing and a contact insert accommodated in the receiving cavity of the insulative housing. The contact insert comprises a plurality of electrical contacts each comprising a contacting portion resiliently extending in the receiving cavity of the insulative housing and a tail portion extending beyond the insulative housing. A transitional portion or a conductive trace connects the contacting portion and the tail portion of each electrical contact. The transitional portions or conductive traces of a first group of electrical contacts are located in a first horizontal plane and the transitional portions or conductive traces of a second group of electrical contacts are located in a second horizontal plane vertically offset or spaced from the first horizontal plane. The transitional portions or conductive traces of the first group of electrical contacts are to some extent vertically overlapped or aligned with the transitional portions or conductive traces of the second group of electrical contacts.  
           [0014]    Other objects, advantages and novel features of the invention will become more apparent from the following detailed description of the present embodiment when taken in conjunction with the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]    [0015]FIG. 1 is a perspective view of an electrical connector in accordance with the present invention;  
         [0016]    [0016]FIG. 2 is a view similar to FIG. 1 but taken from a different perspective;  
         [0017]    [0017]FIG. 3 is a perspective view of an insulative housing of the electrical connector of FIG. 1;  
         [0018]    [0018]FIG. 4 is a view similar to FIG. 3, but taken from another perspective;  
         [0019]    [0019]FIG. 5 is a perspective view of a contact insert of the electrical connector of FIG. 1 in accordance with a first embodiment of the present invention;  
         [0020]    [0020]FIG. 6 is a view similar to FIG. 5 but an insulative portion of the contact insert is removed away;  
         [0021]    [0021]FIG. 7 is a top plan view of FIG. 6;  
         [0022]    [0022]FIG. 8 is a front view of FIG. 6;  
         [0023]    [0023]FIG. 9 is a rear view of FIG. 6;  
         [0024]    [0024]FIG. 10 is a side elevational view of FIG. 6;  
         [0025]    [0025]FIG. 11 is a perspective view of a second group of the electrical contacts of FIG. 6;  
         [0026]    [0026]FIG. 12 is a perspective view of a contact insert of the electrical connector of FIG. 1 in accordance with a second embodiment of the present invention; and  
         [0027]    [0027]FIG. 13 is a perspective view of a printed circuit board of the contact insert of FIG. 12 showing a second plane thereof. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0028]    Referring to FIGS. 1 and 2, an electrical connector  1 , such as a modular jack, in accordance with a first embodiment of the present invention comprises an insulative housing  2 , a conductive shield  3  enclosing the insulative housing  2  and a contact insert  4 .  
         [0029]    Referring also to FIGS. 3 and 4, the insulative housing  2  comprises a top wall  20 , a pair of opposite side walls  22  and a bottom wall  24  opposite to and connected by the side walls  22  to the top wall  20 . The insulative housing  2  defines a receiving cavity  26  recessed from a front surface  28  thereof and confined by the top, side and bottom walls  20 ,  22 ,  24  thereof for receiving a plug or complementary electrical connector (not shown) therein. A comb-shaped mid-wall  21  extends vertically in a lower and rear portion of the receiving cavity  26  and is perpendicular to the top, side and bottom walls  20 ,  22 ,  24 . A plurality of spaced channels  23  extend upwardly from a lower end of the mid-wall  21  to an upper portion of the mid-wall  21  and communicate with the receiving cavity  26 . A pair of positioning posts  25  extend downwardly from a front portion of the bottom wall  24  to be insertable into for example through holes of a printed circuit board (not shown) when the electrical connector  1  is mounted to the printed circuit board.  
         [0030]    The conductive shield  3  comprises a top wall  30  and a pair of opposite side walls  32  corresponding to the top and the side walls  20 ,  22  of the insulative housing  2 , respectively. The conductive shield  3  comprises a front wall  34  corresponding to the front surface  28  of the insulative housing  2  and having an opening corresponding to the receiving cavity  26 . A rear wall  36  is formed on the conductive shield  3  and is connected to the top and side walls  30 ,  32 . A pair of grounding tabs  38  (only one shown) extend downwardly from lower edges of the side walls  32 .  
         [0031]    Referring also to FIG. 5, the contact insert  4  comprises an insulative portion  40  and eight electrical contacts  41 - 48 . The insulative portion  40  comprises a horizontal section  401  and a vertical section  402  extending downwardly and perpendicularly from a rear portion of the horizontal section  401 .  
         [0032]    Referring specifically to FIGS.  6 - 11 , the electrical contacts  41 - 48  each comprise a tail portion  411 ,  421 ,  431 ,  441 ,  451 ,  461 ,  471 ,  481  for electrically contacting with the printed circuit board on which the electrical connector  1  is mounted, a transitional portion  412 ,  422 ,  432 ,  442 ,  452 ,  462 ,  472 ,  482  extending forwardly from the tail portion  411 ,  421 ,  431 ,  441 ,  451 ,  461 ,  471 ,  481 , and a contacting portion  413 ,  423 ,  433 ,  443 ,  453 ,  463 ,  473 ,  483  extending downwardly and rearwardly from the transitional portion  412 ,  422 ,  432 ,  442 ,  452 ,  462 ,  472 ,  482 .  
         [0033]    The transitional portions  412 ,  442 ,  452 ,  482  of a first group of contacts  41 ,  44 ,  45 ,  48  are generally located in a horizontal plane from which the contacting portions  413 - 483  and the tail portions  411 ,  441 ,  451 ,  481  extend away.  
         [0034]    Each of the transitional portions  412  and  482  comprises a generally U-shaped plate section  4120 ,  4820 . Each U-shaped plate section  4120 ,  4820  comprises a base plate  4121 ,  4821  extending in a front-to-back direction along which the plug complementary connector is inserted into the electrical connector  1  and a pair of leg plates  4122 ,  4822  extending in a direction perpendicular to the front-to-back direction along which the base plate  4121 ,  4821  extends. Each base plate or leg plate has a width larger than other portions of a corresponding electrical contact.  
         [0035]    Each transitional portion  442 ,  452  comprises a generally rectangular plate section  4420 ,  4520  extending laterally from one side thereof into the U-shaped plate sections  4120 ,  4820 , respectively, and substantially surrounded by the base plates  4121 ,  4821  and the leg plates  4122 ,  4822 .  
         [0036]    The transitional portions  422 ,  432 ,  462 ,  472  of a second group of electrical contacts  42 ,  43 ,  46 ,  47  extend firstly rearwardly from the contacting portions  423 ,  433 ,  463 ,  473  in the horizontal plane in which the transitional portions  412 ,  442 ,  452 ,  482  are located and then downwardly to form lower sections  4220 ,  4320 ,  4620 ,  4720  located in another horizontal plane in parallel proximity to the horizontal plane in which the transitional portions  412 ,  442 ,  452 ,  482  are located.  
         [0037]    The lower sections  4220  and  4720  extend respectively first outwardly and laterally to be perpendicular to the front-to-back direction along which the plug complementary connector is inserted into the electrical connector  1 , then rearwardly to be parallel to the insertion direction of the plug complementary connector, and then inwardly and laterally to be again perpendicular to the insertion direction of the plug complementary connector and to perpendicularly connect with the tail portions  421 ,  471 . Thus, the lower sections  4220 ,  4720  are generally U-shaped and as could be clearly seen from FIG. 11, the U-shaped sections  4220 ,  4720  have widths substantially equal to widths of other portions of the electrical contacts  42 ,  47 . The U-shaped sections  4220 ,  4720  are vertically overlapped by the U-shaped plate sections  4120 ,  4820 , respectively.  
         [0038]    Each of the lower sections  4320 ,  4620  is also formed with a generally U-shaped section  4321 ,  4621  generally surrounded by the U-shaped lower sections  4220 ,  4720 , respectively, and substantially vertically overlapped by the U-shaped plate sections  4120 ,  4820 , respectively. A rectangular plate section  4322 ,  4622  diverges from a leg end of the U-shaped sections  4321 ,  4621  to extend into a corresponding U-shaped section  4621 ,  4321  of a corresponding transitional portion  462 ,  432  and to vertically align with the rectangular plate sections  4520 ,  4420 , respectively.  
         [0039]    The tail portions  421 ,  431 ,  461 ,  471  of the second group of electrical contacts  42 ,  43 ,  46 ,  47  extend downwardly a shorter distance from the transitional portions  422 ,  432 ,  462 ,  472  than the tail portions  411 ,  441 ,  451 ,  481  extend downwardly from the transitional portions  412 ,  442 ,  452 ,  482  of the first group of electrical contacts  41 ,  44 ,  45 ,  48 , such that lower ends of the first and second groups of electrical contacts  41 - 48  are, as specifically shown in FIGS. 6 and 10, located in the same level.  
         [0040]    The electrical contacts  41 - 48  are insert molded in the insulative portion  40  to form the contact insert  4 . The transitional portions  412 - 482  are embedded in the horizontal section  401  in two aforementioned different planes (levels), the contacting portions  413 - 483  extend resiliently and slantways beyond a front end of the insulative portion  401 , and the tail portions  413 - 483  extend beyond the vertical section  402 .  
         [0041]    In assembly, the contact insert  4  is inversely inserted in a back-to-front direction into the receiving cavity  26  of the insulative housing  2  with the contacting portions  413 - 483  respectively movably received in the channels  23  of the mid-wall  21 . The tail portions  411 - 481  are electrically connected to terminals  5  (FIGS. 1 and 2) in ways well known to any one of ordinary skill in the pertinent art to be electrically engaged with the printed circuit board on which the electrical connector  1  is mounted, so a detailed description thereabout is omitted herefrom.  
         [0042]    As stated above, the U-shaped plate sections of the transitional portions of the electrical contacts  41 ,  48  vertically overlap (align with) the U-shaped sections of the transitional portions of the electrical contacts  42  and  43 ,  46  and  47 , respectively. The rectangular plate sections  4420  and  4520  of the transitional portions  442  and  452  of the electrical contacts  44  and  45  vertically overlap and/or align with the rectangular plate sections  4622  and  4322  of the transitional portions  462  and  432  of the electrical contacts  46  and  43 , respectively. Through such arrangement, the electrical contacts  42  and  44 ,  44  and  46 ,  46  and  48  are located closer in a horizontal direction than when the transitional portions  412 - 482  are located in turn side by side in a common horizontal plane.  
         [0043]    Referring to FIGS. 12 and 13, a contact insert  4 ′ in accordance with a second embodiment of the present invention comprises eight electrical contacts  41 ′- 48 ′ and a printed circuit board  40 ′. The electrical contacts  41 ′- 48 ′ respectively comprise tail portions  411 ′- 481 ′ (only  411 ′,  441 ′,  451 ′ and  481 ′ shown) and contacting portions  413 ′- 483 ′. The printed circuit board  40 ′ comprises a first plane  400 ′ and a second plane  401 ′. The first plane  400 ′ defines a plurality of conductive traces  412 ′,  442 ′,  452 ′ and  482 ′ thereon corresponding to the electrical contacts  41 ′,  44 ′,  45 ′ and  48 ′, respectively, and the second plane  401 ′ defines a plurality of conductive traces  422 ′,  432 ′,  462 ′ and  472 ′ corresponding to the electrical contacts  42 ′,  43 ,  46 ′ and  47 ′, respectively. The conductive traces  412 ′- 482 ′ are electrically connected with the tail and the contacting portions  411 ′- 481 ′,  413 ′- 483 ′ of the electrical contacts  41 ′- 48 ′, respectively. The shapes of the conductive traces  412 ′- 482 ′ correspond to those of the transitional portions  412 - 482  of the electrical contacts  41 - 48 , respectively, and the overlapping relations between the conductive traces  412 ′- 482 ′ is identical to those between the transitional portions  412 - 482 .  
         [0044]    In use, when the electrical connector  1  needs to work in 10/100 BaseT protocol, desired electrical couplings could be established in the respective differential contact pairs of  41  and  42  ( 41 ′ and  42 ′),  43  and  46  ( 43 ′ and  46 ′),  44  and  45  ( 44 ′ and  45 ′) and of  47  and  48  ( 47 ′ an  48 ′). Unwanted electrical couplings (cross-talks), such as between the electrical contacts  42  and  43  ( 42 ′ and  43 ′) and between the electrical contacts  46  and  47  ( 46 ′ and  47 ′) are balanced by electrical couplings between the electrical contacts  41  and  43  ( 41 ′ and  43 ′) and between the electrical contacts  46  and  48  ( 46 ′ and  48 ′), respectively achieved by the vertical overlapping of the U-shaped sections thereof. Also, unwanted electrical couplings between the electrical contacts  43  and  44  ( 43 ′ and  44 ′) and between the electrical contacts  46  and  45  ( 46 ′ and  45 ′) are balanced by the electrical couplings between the electrical contacts  43  and  45  ( 43 ′ and  45 ′) and between the electrical contacts  46  and  44  ( 46 ′ and  44 ′) respectively achieved by the vertical overlapping of the rectangular-shaped plate sections thereof. Thus, the cross-talk of the electrical contacts  41 - 48  of the electrical connector  1  is effectively reduced.  
         [0045]    When the electrical connector  1  needs to work in 10/1000 BaseT protocol, desired electrical couplings could be established in the respective differential contact pairs of  41  and  42  ( 41 ′ and  42 ′),  43  and  44  ( 43 ′ and  44 ′),  45  and  46  ( 45 ′ and  46 ′) and of  47  and  48  ( 47 ′ and  48 ′). Unwanted electrical couplings, such as between  42  and  43  ( 42 ′ and  43 ′), between  44  and  45  ( 44 ′ and  45 ′) and between  46  and  47  ( 46 ′ and  47 ′) would also be balanced by electrical couplings between  41  and  43  ( 41 ′ and  43 ′), between  43  and  45  ( 43 ′ and  45 ′) and between  46  and  48  ( 46 ′ and  48 ′), respectively established in like ways as described above. So cross-talk of the electrical contacts  41 - 48  is also effectively reduced.  
         [0046]    Thus, the electrical connector  1  is capable of working in either 10/100 BaseT protocol or 10/1000 BaseT protocol.  
         [0047]    As clearly shown in FIGS. 6 and 11, shapes and dimension of the transitional portions  412 ,  442 ,  452 ,  482  of the first group of electrical contacts  41 ,  44 ,  45 ,  48  are complementary with one another and shapes and dimension of the transitional portions  422 ,  432 ,  462 ,  472  of the second group of electrical contacts  42 ,  43 ,  46 ,  47  are complementary with each other, so the first and second groups of electrical contacts could be respectively stamped from one separate metal sheet with little material waste, thereby reducing the manufacturing cost thereof and simplifying the manufacturing procedures thereof.  
         [0048]    Furthermore, the contact insert  4 ,  4 ′ is configured as one unit, the insulative housing  2  needs not consider designing complicated infrastructure to correspond to the varying shapes and dimension of the electrical contacts  41 - 48  ( 41 ′- 48 ′). Therefore, the manufacturing cost of the insulative housing  2  is also reduced.  
         [0049]    Although the conductive traces  412 ′- 482 ′ shown in FIGS. 12 and 13 are directly connected with the electrical contacts  41 ′- 48 ′, they also can be connected to other electronic components, for example capacitors and magnetic. Furthermore, the electrical connector  1  shown herein is a singular port connector, while it could be in multi-port connector, such as side by side and stacked connector fashion, if desired.  
         [0050]    It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.