Electrical connector having impedance matched intermediate connection points

An electrical wafer for electrically connecting to a printed circuit board. The electrical wafer includes an insulative housing and at least one signal conductor disposed in the insulative housing. The at least one signal conductor includes an intermediate portion having a connection point. The connection point includes first and second ends, at least one of which has a width greater than a portion of the at least one signal conductor outside the connection point. The insulative housing has at least one aperture exposing at least a portion of the connection point. A portion of the connection point may be punched out, and a passive circuit element may be placed within the at least one aperture and mounted to the connection point. Multiple electrical wafers may be coupled together by a stiffener and connected to a backplane connector.

FIELD OF THE INVENTION

This invention relates generally to an electrical connector for connecting printed circuit boards and methods of manufacturing such an electrical connector and, more specifically, to an electrical connector comprising one or more wafers having impedance matched connection points for passive circuit elements.

BACKGROUND OF THE INVENTION

Modern electronic circuitry is often built on printed circuit boards. The printed circuit boards are then interconnected to create an electronic system, such as a server or a router for a communications network. Electrical connectors are generally used to make these interconnections between the printed circuit boards. Typically, connectors are made of two pieces, with one piece on one printed circuit board and the other piece on another printed circuit board. The two pieces of the connector assembly mate to provide signal paths between the printed circuit boards.

An electrical connector should generally have a combination of several properties. For example, it should provide signal paths with appropriate electrical properties such that the signals are not unduly distorted as they move between the printed circuit boards. In addition, the connector should ensure that the two pieces mate easily and reliably. Furthermore, the connector should be rugged so that it is not easily damaged by handling of the printed circuit boards. For many applications, it is also important that the connector have high density, meaning that the connector can carry a large number of electrical signals per unit length.

Examples of electrical connectors possessing these desirable properties include VHDM®, VHDM®-HSD, and GbX® connectors manufactured and sold by the assignee of the present invention, Teradyne, Inc.

One of the disadvantages of conventional electronic systems is the need, oftentimes, to populate the surfaces of the interconnected printed circuit boards with passive circuit elements. These passive circuit elements, such as capacitors, inductors and resistors, may be needed, for example: (i) to block or at least reduce the flow of direct current (“DC”) caused by potential differences between various electronic components on the interconnected printed circuit boards; (ii) to provide desired filtering characteristics; and/or (iii) to reduce data transmission losses. However, these passive circuit elements take up precious space on the board surface (thus reducing the space available for signal paths). In addition, where these passive circuit elements on the board surface are connected to conductive vias, there could be undesirable signal reflections at certain frequencies due to impedance discontinuity and resonant stub effects.

What is desired, therefore, is an electrical connector and methods of manufacturing such an electrical connector that generally possesses the desirable properties of the existing connectors described above, but also provides passive circuit elements in the connector to deliver the desired qualities provided by the passive circuit elements described above. And it is further desired that such an electrical connector provide the passive circuit elements cost effectively.

SUMMARY OF THE INVENTION

In accordance with an aspect of the present invention, there is provided an electrical wafer for connecting to a printed circuit board. The electrical wafer includes an insulative housing and at least one signal conductor including an intermediate portion having a connection point. The connection point includes first and second ends. At least one of the first and second ends has a width greater than a portion of the at least one signal conductor outside the connection point. The insulative housing includes at least one aperture exposing at least a portion of the connection point.

In accordance with another aspect of the present invention, there is provided an electrical connector including a plurality of wafers and a stiffener configured to hold the plurality of wafers in parallel to one another. Each wafer includes an insulative housing and at least one signal conductor including an intermediate portion having a connection point. The connection point includes first and second ends. At least one of the first and second ends has a width greater than a portion of the at least one signal conductor outside the connection point. The insulative housing of each wafer includes at least one aperture exposing at least a portion of the connection point of the at least one signal conductor of each wafer.

In accordance with yet another aspect of the present invention, there is provided an electrical connector assembly including a plurality of wafers, a stiffener configured to hold the plurality of wafers in parallel to one another, and a back plane connector configured to connect to a first end of each wafer. Each wafer includes an insulative housing and at least one signal conductor including an intermediate portion having a connection point. The connection point includes first and second ends. At least one of the first and second ends has a width greater than a portion of the at least one signal conductor outside the connection point. The insulative housing of each wafer includes at least one aperture exposing at least a portion of the connection point of the at least one signal conductor of each wafer.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1shows a perspective view of a prior art electrical connector assembly10illustrated as FIG. 1 in U.S. Pat. No. 6,409,543. The '543 patent, which is directed to the GbX® connector, is assigned to the assignee of the present invention and is incorporated by reference herein. The electrical connector assembly10includes a daughtercard connector20that is connectable to a first printed circuit board (not shown) and a backplane connector50that is connectable to a second printed circuit board (not shown). The daughtercard connector20has a plurality of modules or wafers22which are preferably held together by a stiffener24.

Each wafer22includes a plurality of signal conductors (not shown), a shield plate (not shown), and a dielectric housing26that is formed around at least a portion of each of the plurality of signal conductors and the shield plate. Each of the signal conductors has a first contact end32connectable to the first printed circuit board and a second contact end34mateable to the backplane connector50. Each shield plate has a first contact end42connectable to the first printed circuit board and a second contact end44mateable to the backplane connector50.

The backplane connector50includes an insulative housing52and a plurality of signal conductors54held by the insulative housing52. The plurality of signal conductors of the wafer22and the backplane connector50is arranged in an array of differential signal pairs. The backplane connector50also includes a plurality of shield plates56that are located between rows of differential signal pairs. Each of the signal conductors54has a first contact end62connectable to the second printed circuit board and a second contact end64mateable to the second contact end34of the corresponding signal conductor30of the daughtercard connector20. Each shield plate56has a first contact end72connectable to the second printed circuit board and a second contact end74mateable to the second contact end44of the corresponding shield plate of the daughtercard connector20.

The wafers22do not have passive circuit elements that would provide desirable characteristics, such as DC flow minimization, desired filtering characteristics, or data transmission loss reduction.

FIG. 2shows a perspective view of another prior art wafer, generally designated as100inFIG. 1and illustrated in FIG. 2 of U.S. Pat. No. 7,285,018. The '018 patent is assigned to the assignee of the present invention and is incorporated by reference herein. The '018 patent describes the wafer100as addressing some of the desires noted in the Background of the Invention section of the '018 patent, which desires are repeated herein in the Background of the Invention section.

With reference toFIG. 2herein, the wafer100includes a plurality of signal conductors110and an insulative housing102. The signal conductors110are more clearly shown inFIG. 3, which illustrates the wafer100ofFIG. 2with a portion of the insulative housing102removed from the drawing to reveal the signal conductors110.

Referring toFIGS. 2 and 3, the signal conductors110are arranged as differential signal pairs. Each signal conductor110has a first contact end112, a second contact end114, and an intermediate portion116therebetween. The intermediate portion116of the signal conductor110is disposed within the insulative housing102. The wafer100also includes a ground conductor member or a shield plate having a first contact end122and a second contact end124. The first contact ends112,122, which are illustrated as press-fit “eye of the needle” contact ends, are connectable to a first printed circuit board (not shown). The second contact ends114,124are connectable to the backplane connector50ofFIG. 1.

Attached to the intermediate portion116of each signal conductor110is a passive circuit element140. Each passive circuit element140is disposed in an aperture145in the insulative housing102and extends entirely through the insulative housing102and beyond the outer surface of the insulative housing102. The passive circuit element140includes at least a capacitor or an inductor housed in an insulative package and is a commercially available off-the-shelf component. For example, if the passive circuit element140is desired to function as a direct current blocking circuit, then one of the ceramic or tantalum chip capacitors that are sold by KEMET Electronics Corporation of Greenville, S.C. can be utilized. If the passive circuit element140is desired to function as a high frequency passive equalization circuit, then one of the resistor/inductor/capacitor packages that are sold by Maxim Integrated Products, Inc. of Sunnyvale, Calif. can be utilized.

As illustrated inFIG. 2, the passive circuit elements140are disposed within the apertures145. The apertures145are voids in the insulative housing102providing access to the interior of insulative housing102and the conductors110so that the passive circuit elements140may be connected to the conductors110, as needed. Because the insulative housing102is formed from a dielectric, the apertures145, while desirable for installing the passive circuit elements140, change the impedance in the conductors110in the apertures145compared to the portions of the conductors110not in the apertures. If signals in the 5-25 GHz range are applied to the conductors110, the impedance mismatch in the conductors110(with or without the passive circuit elements140) may increase transmission loses, e.g., by introducing undesirable signal reflections. Accordingly, a wafer with matched impedance connection points for passive circuit elements is desirable.

Illustrated inFIG. 4is a perspective view of an electrical connector400, in accordance with an exemplary embodiment of the present invention. The electrical connector400comprises a wafer405coupled to a plurality of like wafers450by a stiffener425. It is to be understood that any of such wafers450may be constructed as the wafer405is constructed and may be provided with the same or different passive circuit elements described below. Illustrated inFIG. 5Ais a plan view of the front or top surface of the wafer405illustrated inFIG. 4, in accordance with an exemplary embodiment of the present invention. The wafer405comprises a plurality of electrical conductors410A and410B (illustrated inFIGS. 6A-6C), onto each of which may be mounted a passive circuit element500. The wafer405further comprises an insulative housing430. Illustrated inFIG. 6Ais a plan view of the wafer405with the insulative housing430removed to expose the plurality of electrical conductors410and passive circuit elements500, in accordance with an exemplary embodiment of the present invention.FIGS. 4,5A, and6A are now described together.

Each pair of the electrical conductors410A and410B forms a differential pair410of respective signal conductors410A and410B. Each differential pair410comprises the pair of respective signal conductors410A and410B for transmitting signals within frequency ranges of 5-25 or 5-40 GHz. For each differential pair410, the signal conductors410A and410B are spaced at a first distance B-B which is smaller than a second distance C-C between the signal conductors410A and410B of adjacent differential pairs410. In an exemplary embodiment, C-C is at least three times that of B-B. An exemplary value for B-B is 0.45 mm.

Although the pair of signal conductors410A and410B are labeled for one differential pair410inFIG. 6A(and inFIGS. 6B and 6C), it is to be understood that description herein relating to the conductors410A and410B applies to the conductors of all of the plurality of differential pairs410labeled in the figures. Further, it is to be understood that althoughFIG. 6A(andFIGS. 6B and 6C) is illustrated and described as comprising a plurality of differential pairs410, other embodiments of the wafer405comprising one differential pair410is contemplated.

Each of the signal conductors410A and410B has a first contact end412, a second contact end414, and an intermediate portion416there between. The intermediate portion416of each of the signal conductors410A and410B is disposed within the insulative housing430. Desirably, the wafer405also includes a ground conductor member or shield plate420adjacent to each differential pair410. Each ground conductor member420comprises a first contact end422and a second contact end424and may or may not be coplanar with the differential pairs410. In the embodiment illustrated inFIG. 4, the ground conductor members420are separate ground conductor members disposed between the differential pairs410. It is to be understood that the ground conductor members420are not so limited. In a further exemplary embodiment, the ground conductor members420are formed as a unitary shield plate disposed in a plane adjacent to the differential pairs410.

The first contact ends412and422, which are illustrated as press-fit “eye of the needle” contact ends, are connectable to a first printed circuit board (not shown), such as a daughtercard. The second contact ends414and424are connectable to a second printed circuit board or a mating connector. An example of a mating connector is the backplane connector50ofFIG. 1. It should be noted that while an exemplary embodiment of the present invention is directed to a two-piece, shielded, differential pair electrical connector assembly (comprising the electrical connector400and the backplane connector50), the concepts described herein are applicable to a one-piece connector, an unshielded connector, a single-ended connector, or any other type of electrical connector.

Disposed in the insulative housing430are a plurality of apertures440and450(shown inFIGS. 5C and 5D). The apertures440provide access to a plurality of electrical connection points510(shown inFIGS. 5B and 6B) of the signal conductors410A and410B for mounting passive circuit elements500thereon. In an exemplary embodiment, the insulative housing430is formed from a dielectric (lossy) material, and the apertures440are gaps or voids in the dielectric material.

FIG. 5Billustrates the connection points510of the signal conductors410A and410B of the differential pairs410exposed through the apertures440prior to the passive circuit elements500being mounted thereon, in accordance with an exemplary embodiment of the present invention. Illustrated inFIG. 6Bis a plan view of the wafer405ofFIG. 5Bwith the insulative housing430removed to expose the connection points510of the plurality of differential pairs410, in accordance with an exemplary embodiment of the present invention. Illustrated inFIG. 6Cis a plan view of the wafer405ofFIG. 6Bin which portions of the signal conductors410A and410B have been punched out forming gaps520to accommodate the mounting of the passive circuit elements500, in accordance with an exemplary embodiment of the present invention. To summarize,FIGS. 5B and 6Billustrate the configuration of the connection points510prior to the voids or gaps520being punched in the conductors410A and410B for mounting of the passive circuit elements500in a manufacturing process.FIG. 6Cillustrates the gaps520after the portions have been punched out but prior to mounting of the passive circuit elements500in a manufacturing process.FIGS. 5A,5B, and6A-6C are now described together.

Each signal conductor410A and410B for each differential pair410comprises at least one connection point510located in the intermediate portion416of the signal conductor410A,410B. The connection point510of each signal conductor410is provided for mounting the passive circuit element500. After being punched, as illustrated inFIG. 6C, the intermediate portion416of each conductor410A,410B of each differential pair410includes a gap or break520at the connection point510. For example, the intermediate portion416of the conductor410A includes a gap or break520at the connection point510, as illustrated inFIG. 6C. After being mounted, the passive circuit element500straddles the break520when installed at the connection point510. It is to be understood that for any conductor410A or410B that is not to include a passive circuit element500, no punch or break520is formed at the connection point510. Thus, for such conductor410A or410B, the connection point510would appear as illustrated inFIGS. 5B and 6B.

FIG. 5Aillustrates that the passive circuit elements500are visible through their respective apertures440in the insulative housing430after being mounted.FIG. 5Billustrates that the connection points510of the differential pairs410are visible through their respective apertures prior to the mounting of the passive circuit elements500. Because the insulative housing430is formed from a dielectric, the voids in the insulative housing430forming the apertures440, while desirable for installing the passive circuit elements500, change the impedance seen by the conductors410A and410B of the differential pairs410. Accordingly, it is desirable to minimize the size of the apertures440in the dielectric housing430and, generally, to minimize the change in impedance caused by providing access to the conductors410A and410B for the option of installing passive circuit elements500.

Accordingly, in an exemplary embodiment, each aperture440has an elongated octagonal shape, as seen inFIGS. 5A and 5B, rather than a square or rectangular shape, to reduce the size of the void forming the aperture440. The octagonal shape results in less material in the insulative housing430being absent compared to a square or rectangular shape. By reducing the size of the void, the elongated octagonal shape reduces the change in impedance seen by the conductors410A and410B of the differential pairs410compared to the impedance change caused by a square or rectangular shape.

It is to be understood that the apertures440are not limited to being elongated octagons having straight edges. Other shapes such as ovals or ellipses are contemplated for reducing the amount of dielectric absent from the insulative housing430in the apertures. Illustrated inFIG. 8Cis an exemplary alternative embodiment of the aperture845, generally designated as845′ inFIG. 8C, in accordance with an exemplary embodiment of the present invention. The aperture845′ has a modified octagonal shape comprising substantially straight edges846connected by inwardly curved edge corner segments847. The edges846and corner segments847are connected by curved ends848. By including inwardly curved edge corner segments847and curved ends848, the size of the aperture845′ is further reduced over that of the aperture845, thereby further reducing the effect on impedance in the conductors410A and410B. It is to be understood that the substantially straight edges846may be curved inwardly in a further exemplary embodiment to adjust the effect on the impedance in the conductors410A and410B.

Referring now toFIGS. 5C and 5D, there are illustrated plan views of the rear or bottom of the wafer405, as respectively illustrated inFIGS. 5A and 5B, in accordance with an embodiment of the present invention.FIG. 5Cillustrates the underside of the differential pairs410having the passive circuit elements500mounted thereon.FIG. 5Dillustrates the connection points510of the differential pairs410prior to the breaks520being formed. As can be seen inFIGS. 5C and 5D, the rear or bottom of the wafer405comprises a plurality of circular apertures450in the insulative housing430. Although the apertures450are illustrated as being circular, it is to be understood that the apertures450may have any of the shapes the apertures440may have.

The apertures450accommodate a punching operation to punch out the breaks520in the signal conductors410A and410B of the differential pairs410so that the passive circuit elements500may be mounted across the breaks520. By including the apertures450in the rear of the insulative housing430, the punched-out portions of the conductors410A and410B may fall away from the wafer405so that the risk of shorts caused by the punched-out portions is minimized. The apertures450are also shaped to minimize their effect on the impedance of the conductors410A and410B.

Despite the fact that the apertures440and450are shaped as elongated octagons, modified elongated octagons, ovals, or ellipses, the apertures440and450still change the impedances seen by the conductors410A and410B of the differential pairs410. Accordingly, to counteract this change in impedance, the connection points510of the conductors410A and410B are shaped as barbells, in accordance with an exemplary embodiment of the present invention.

Illustrated inFIG. 7Ais an enlarged view of a portion A of the wafer405ofFIG. 4, in accordance with an exemplary embodiment of the present invention. As seen inFIG. 7A, the aperture440has an elongated octagonal shape and is formed by an octagonal void in the insulative housing430. Seen through the aperture440is the connection point510of the conductor410A within the wafer405. Discussion of the portion A of the wafer405is now made, understanding that the discussion is applicable to all connection points510in the wafer405.

Referring now toFIGS. 6B and 7Atogether, the barbell shape of the connection point510of the conductor410A,410B is formed by two circular portions512and514of the conductor410A,410B connected by an intermediate portion516of the conductor410A,410B (also seeFIG. 8C). The circular portions512and514are wider than the intermediate portion516, and the intermediate portion516is equal in width to the portions of the conductor410A,410B outside of the connection point510. The circular portions512and514of the conductor410A,410B increase the impedance of the conductor410A,410B to counteract the change in impedance seen by the differential pair410at the apertures440and450caused by the voids in the dielectric material of the insulative housing430. Thus, when in its uncut configuration, as shown inFIG. 7, the connection point510of the conductor410A,410B is impedance matched to the remainder of the conductor410A,410B. It is to be understood that the circular portions512and514are not limited to having circular shapes. Therefore, in an exemplary embodiment, the end portions512and514may have shapes other than circles, such as squares, hexagons, etc., which shapes are wider than the intermediate portion516and provide for impedance matching for the connection point510.

In addition to being impedance matched to the remainder of the conductor410A,410B, the connection point510is also designed for mounting a passive circuit element, such as the passive circuit element500, in series with the conductor410A,410B. In an exemplary embodiment of the present invention, the passive circuit element500is mounted to the conductor410A,410B at the connection point510, as illustrated inFIG. 7D(described below). The passive circuit element500may be selected and mounted depending on the application for the wafer405.

Referring now toFIG. 9, there is illustrated a flowchart900of a manufacturing process for mounting a passive circuit element500to the connection point510of the conductor410A, in accordance with an exemplary embodiment of the present invention. It is to be understood that as the various process steps of the flowchart900are described, some of the steps need not be included in order to manufacture a connector in accordance with the present invention. Furthermore, the sequence of some of the steps may be varied. Description ofFIG. 9is made with reference toFIGS. 7A-E, which illustrate the connection point510as it is prepared and mounted with the passive circuit element500, in accordance with an exemplary embodiment of the present invention. The flowchart900illustrates process steps for modifying and adapting a wafer of an existing connector, such as the wafer405shown inFIG. 5B, to accept the passive circuit element500.

The method900begins with providing a wafer, such as the wafer405ofFIG. 4, Step910. In the Step910, the wafer405is formed by stamping the signal conductors410A and410B from a lead frame, as is known in the art. The signal conductors410A and410B may be made of a solder wettable material, such as beryllium-copper or the like, and the intermediate portions416of the signal conductors410A and410B and specifically the connection points510may be provided with solder wettable material, such as tin-lead coating, for soldering the passive circuit elements500in place. Outside the intermediate portions416of the conductors410A and410B, the conductors410A and410B may be coated with nickel or other non-solder wetting material.FIG. 6Billustrates the plurality of differential pairs410(comprising the conductors410A and410B) and the plurality of ground conducting members420after being punched from the lead frame. It is to be understood that the signal conductors410A and410B are formed in the lead frame to include the connections points510having the barbell shapes and the circular portions512and514illustrated inFIG. 6B.

While holding the signal conductors410A and410B of the plurality of differential pairs410in place by clamps or fingers, the insulative housing430of the wafer405is injection molded around the plurality of differential pairs410. The housing430is molded to form the apertures440and450through which at least a portion of the connection points510are exposed. The wafer405is thereby provided in the Step910. An exemplary view of the connection points510is shown inFIG. 7A.

The method900continues to a Step912in which the intermediate portions516of the connection points510of selected conductors410A,410B of selected differential pairs410are punched and removed to form selected punch holes or breaks520to sever the electrical connection between the circular portions512and514of the selected connection points510, as illustrated inFIG. 7B. It is desirable that the punch holes or breaks520pass entirely through the intermediate portion516to ensure electrical separation of the circular portions512and514. In an exemplary embodiment, the punch holes520are rectangular, as illustrated inFIG. 7B.

In a Step914, the water405is cleaned and inspected. This step can be performed manually or automatically, and can be bypassed if desired. In a Step916, solder paste or conductive adhesive712and714is applied, respectively, to the circular portions512and514of the selected connection points510, as illustrated inFIG. 7C. The solder paste or conductive adhesive does not flow into the punch holes520because of the surface tension and viscosity of the solder paste or conductive adhesive and because of the size of the punch holes520.

A passive circuit element500is then placed onto each selected connection points510to bridge the punch hole520, Step918. In an exemplary embodiment, the passive circuit element500may be any surface mounted passive device, such as surface-mounted resistors, capacitors, or inductors, capable of being disposed in the apertures440, as illustrated inFIG. 7D. The surface mounted passive device may be encapsulated in an insulative package and may be a resistor, capacitor, or inductor, commercially available off the shelf. For example, if the passive circuit element500is desired to function as a direct current blocking circuit, then one of the ceramic or tantalum chip capacitors that are sold by KEMET Electronics Corporation of Greenville, S.C. can be utilized. The technical information for these ceramic or tantalum chip capacitors is available from KEMET (www.kemet.com) and is incorporated by reference herein. If the passive circuit element500is desired to function as a high frequency passive equalization circuit, then one of the resistor/inductor/capacitor packages that are sold by Maxim Integrated Products, Inc. of Sunnyvale, Calif. can be utilized. The technical information for these packages is available from Maxim (www.maxim-ic.com) and is incorporated by reference herein.

If solder is used, in a Step920, the passive circuit element500is soldered to the circular portions512and514of the selected connection point510by heating the solder paste712and714. When heated, flux contained in solder paste712and714evaporates, thereby preparing the circular portions512and514. The solder712and714then melts to bind the passive circuit element500to the circular portions512and514. The passive circuit element500is thereby mounted to the connection point510. If conductive paste is used, the passive circuit element500is bound to the circular portions512and514in the Step918, and the Step920is bypassed.

While it is desirable in the Step916to apply the solder paste or conductive adhesive to the circular portions512and514of the connection point510, it is to be understood that the solder paste/conductive adhesive may instead be applied to the ends of the passive circuit element500before or after the Step918or to both the remaining circular portions512and514of the selected connection point510and the ends of the passive circuit elements500.

In a Step922, the attachment of the mounted passive circuit element500is inspected, and in a Step924, the attachment area around the passive circuit element500and the portions of the circular portions512and514remaining exposed are cleaned. The attachment of the passive circuit element500is then tested for electrical continuity across the connection point510, Step926. If the attachment test is successful, insulating material710is deposited into the aperture440, Step928, as illustrated inFIG. 7E. The insulating material710is then cured by ultraviolet light, Step930, and the wafer405is assembled to the plurality of wafers450to form the connector400, Step932, in accordance with an exemplary embodiment of the present invention. In an exemplary embodiment, the insulating material710is also deposited into the aperture450in the Step928and is cured in the Step930. Encapsulation is advantageous to keep moisture out, absorb shocks and vibration, and prevent conductive whiskers from forming at the connection point510.

It is to be understood that the Steps912through930are performed for all connection points510selected to receive a passive circuit element500prior to the Step932being performed. Further, the connection points510of the conductors410A and410B not selected to receive passive circuit elements500need not have Steps912-930performed thereon and, therefore, need not have their respective apertures440encapsulated.

While the flowchart900concerns cutting and removing a portion516of each selected connection point510after the insulative housing430has been molded around the plurality of differential pairs410, it is certainly possible, and in some cases even preferable, to cut and remove the portion516of each selected connection point510before the insulative housing430has been molded around the plurality of differential pairs410.

Referring now toFIGS. 8A and 8B, there are illustrated exemplary dimensions of an exemplary connection point510and exemplary apertures440and450prior to a passive circuit element500being mounted. Dimension X1in the figures is the length of the aperture440. Dimension O is the width of the aperture440. Dimension X2is the diameter of the aperture450. The intermediate portion516of the connection point510has a length Y and a width M. The circular portions512and514of the connection point510have a length Z and a width N.

In an exemplary embodiment of the present invention, the passive circuit elements500may be packaged in a 0402 package known in the art. The dimensions for such package are as follows: 1.00 mm length; 0.50 mm height; and 0.50 mm width. If such package is used, the exemplary values for the dimensions illustrated inFIGS. 8A and 8Bare as follows: X1=1.60 mm; X2=1.40 mm; Y=0.46 mm; Z=0.8 mm; M=0.3 mm; N=0.5 mm; and O=1.06 mm. It is to be understood that the dimensions for each exemplary connection point510and apertures440and450having a passive circuit element500in a 0402 package may equal to the foregoing.

Other package sizes for the passive circuit elements500are contemplated. For example, the passive circuit elements500may be packaged in a 0201 package known in the art. The dimensions for such package are as follows: 0.50 mm length; 0.25 mm height; and 0.25 mm width. It is to be understood that for passive circuit elements500packaged in 0201 packages, the exemplary values for the dimensions illustrated inFIGS. 8A and 8Bare half the exemplary values for such dimensions when a 0402 package is used.

It is to be understood that the foregoing exemplary dimensions are not to be construed as limitations on the sizes of the exemplary connection point510and apertures440and450. Rather, it is to be understood that as the sizes of the passive circuit elements500are changed, the dimensions of the exemplary connection point510and apertures440and450may change accordingly. For example, if the passive circuit elements500are shrunk by a factor of ½, ¼, etc. over the foregoing exemplary sizes, the dimensions of the exemplary connection point510and apertures440and450may also be shrunk by a factor of ½, ¼, etc. over the exemplary foregoing dimensions.

Having described the preferred embodiment of the invention, it will now become apparent to one of ordinary skill in the art that other embodiments incorporating their concepts may be used. Accordingly, these embodiments should not be limited to disclosed embodiments but rather should be limited only by the spirit and scope of the appended claims. All publications and references cited herein are expressly incorporated herein by reference in their entirety.