Communications connector with floating wiring board for imparting crosstalk compensation between conductors

A communications connector includes: a dielectric mounting substrate; a plurality of conductors mounted in the mounting substrate; and a wiring board. Each of the conductors includes a fixed end portion mounted in the mounting substrate and a free end portion, each of the free end portions being positioned in side-by-side and generally parallel relationship, and each of the fixed end portions being positioned in side-by side and generally parallel relationship. The wiring board is positioned between the fixed and free end portions of the conductors, the wiring board being generally perpendicular to the conductors, the wiring board including first and second conductive traces that are electrically insulated from each other. First and second conductors are electrically connected with the first and second traces. The first and second conductive traces are arranged on the wiring board to create a crossover between the first and second conductors.

FIELD OF THE INVENTION

The present invention relates generally to communication connectors and more particularly to near-end crosstalk (NEXT) and far-end crosstalk (FEXT) compensation in communication connectors.

BACKGROUND OF THE INVENTION

In an electrical communication system, it is sometimes advantageous to transmit information signals (video, audio, data) over a pair of wires (hereinafter “wire-pair” or “differential pair”) rather than a single wire, wherein the transmitted signal comprises the voltage difference between the wires without regard to the absolute voltages present. Each wire in a wire-pair is susceptible to picking up electrical noise from sources such as lightning, automobile spark plugs and radio stations to name but a few. Because this type of noise is common to both wires within a pair, the differential signal is typically not disturbed. This is a fundamental reason for having closely spaced differential pairs.

Of greater concern, however, is the electrical noise that is picked up from nearby wires or pairs of wires that may extend in the same general direction for some distances and not cancel differentially on the victim pair. This is referred to as crosstalk. Particularly, in a communication system involving networked computers, channels are formed by cascading plugs, jacks and cable segments. In such channels, a modular plug often mates with a modular jack, and the proximities and routings of the electrical wires (conductors) and contacting structures within the jack and/or plug also can produce capacitive as well as inductive couplings that generate near-end crosstalk (NEXT) (i.e., the crosstalk measured at an input location corresponding to a source at the same location) as well as far-end crosstalk (FEXT) (i.e., the crosstalk measured at the output location corresponding to a source at the input location). Such crosstalks occur from closely-positioned wires over a short distance. In all of the above situations, undesirable signals are present on the electrical conductors that can interfere with the information signal. When the same noise signal is added to each wire in the wire-pair, the voltage difference between the wires will remain about the same and differential cross-talk is not induced, while at the same time the average voltage on the two wires with respect to ground reference is elevated and common mode crosstalk is induced. On the other hand, when an opposite but equal noise signal is added to each wire in the wire pair, the voltage difference between the wires will be elevated and differential crosstalk is induced, while the average voltage on the two wires with respect to ground reference is not elevated and common mode crosstalk is not induced.

U.S. Pat. No. 5,997,358 to Adriaenssens et al. (hereinafter “the '358 patent”) describes a two-stage scheme for compensating differential to differential NEXT for a plug-jack combination (the entire contents of the '358 patent are hereby incorporated herein by reference, as are U.S. Pat. Nos. 5,915,989; 6,042,427; 6,050,843; and 6,270,381). Connectors described in the '358 patent can reduce the internal NEXT (original crosstalk) between the electrical wire pairs of a modular plug by adding a fabricated or artificial crosstalk, usually in the jack, at one or more stages, thereby canceling or reducing the overall crosstalk for the plug-jack combination. The fabricated crosstalk is referred to herein as a compensation crosstalk. This idea can often be implemented by twice crossing the path of one of the differential pairs within the connector relative to the path of another differential pair within the connector, thereby providing two stages of NEXT compensation. This scheme can be more efficient at reducing the NEXT than a scheme in which the compensation is added at a single stage, especially when the second and subsequent stages of compensation include a time delay that is selected to account for differences in phase between the offending and compensating crosstalk. This type of arrangement can include capacitive and/or inductive elements that introduce multi-stage crosstalk compensation, and is typically employed in jack lead frames and PWB structures within jacks. These configurations can allow connectors to meet “Category 6” performance standards set forth in ANSI/EIA/TIA 568, which are primary component standards for mated plugs and jacks for transmission frequencies up to 250 MHz.

Alien NEXT is the differential crosstalk that occurs between communication channels. Obviously, physical separation between jacks will help and/or typical crosstalk approaches may be employed. However, a problem case may be “pair3” of one channel crosstalking to “pair3” of another channel, even if the pair3plug and jack wires in each channel are remote from each other and the only coupling occurs between the routed cabling. To reduce this form of alien NEXT, shielded systems containing shielded twisted pairs or foiled twisted pair configurations may be used. However, the inclusion of shields can increase cost of the system. Another approach to reduce or minimize alien NEXT utilizes spatial separation of cables within a channel and/or spatial separation between the jacks in a channel. However, this is typically impractical because bundling of cables and patch cords is common practice due to “real estate” constraints and ease of wire management.

In spite of recent strides made in improving mated connector (i.e., plug-jack) performance, and in particular reducing crosstalk at elevated frequencies (e.g., 500 MHz—see U.S. patent application Ser. No. 10/845,104, entitled NEXT High Frequency Improvement by Using Frequency Dependent Effective Capacitance, filed May 4, 2004, the disclosure of which is hereby incorporated herein by reference), channels utilizing connectors that rely on either these teachings or those of the '358 patent can still exhibit unacceptably high alien NEXT at very high frequencies (e.g., 500 MHz). As such, it would be desirable to provide connectors and channels used thereby with reduced alien NEXT at very high frequencies.

SUMMARY OF THE INVENTION

The present invention can provide communications jacks with improved differential to common mode and differential to differential NEXT and FEXT performance, particularly at high frequencies. As a first aspect, embodiments of the present invention are directed to a communications connector, comprising: a dielectric mounting substrate; a plurality of conductors mounted in the mounting substrate; and a wiring board. Each of the conductors includes a fixed end portion mounted in the mounting substrate and a free end portion, each of the free end portions being positioned in side-by-side and generally parallel relationship, and each of the fixed end portions being positioned in side-by side and generally parallel relationship. The wiring board is positioned between the fixed and free end portions of the conductors, the wiring board being generally perpendicular to the conductors. The wiring board includes a first conductive trace. A first of the plurality of conductors is electrically connected with the trace such that the fixed end portion and the free end portion of the first conductor are in non-aligned relationship. In this configuration, the wiring board can be used to provide changes in direction to the first conductor, particularly if the first conductor is to cross over another conductor to compensate for crosstalk.

In some embodiments, the wiring board is a “floating” wiring board that is suspended above and spaced from the mounting substrate. This configuration enables the wiring board to move with the conductors when they deflect in response interconnection with another connector.

As a second aspect, embodiments of the present invention are directed to a communications connector, comprising: a dielectric mounting substrate; a plurality of conductors mounted in the mounting substrate; and a wiring board. Each of the conductors includes a fixed end portion mounted in the mounting substrate and a free end portion, each of the free end portions being positioned in side-by-side and generally parallel relationship, and each of the fixed end portions being positioned in side-by side and generally parallel relationship. The wiring board is positioned between the fixed and free end portions of the conductors, the wiring board being generally perpendicular to the conductors, the wiring board including first and second conductive traces that are electrically insulated from each other. A first conductor is electrically connected with the first trace, and a second conductor is electrically connected with the second trace, such that the fixed end portion of the first conductor and the free end portion of the second conductor are substantially aligned, and the fixed end portion of the second conductor and the free end portion of the first conductor are substantially aligned. Thus, this configuration can enable conductors to be desirably crossed over each other.

As a third aspect, embodiments of the present invention are directed to a communications connector, comprising: a dielectric mounting substrate; a plurality of conductors mounted in the mounting substrate; and a wiring board. Each of the conductors includes a fixed end portion mounted in the mounting substrate and a free end portion, each of the free end portions being positioned in side-by-side and generally parallel relationship, and each of the fixed end portions being positioned in side-by side and generally parallel relationship. The wiring board is positioned between the fixed and free end portions of the conductors, the wiring board being generally perpendicular to the conductors, the wiring board including first and second conductive traces that are electrically insulated from each other. First and second conductors are electrically connected with the first and second traces. The first and second conductive traces are arranged on the wiring board to create a crossover between the first and second conductors.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

The present invention will be described more particularly hereinafter with reference to the accompanying drawings. The invention is not intended to be limited to the illustrated embodiments; rather, these embodiments are intended to fully and completely disclose the invention to those skilled in this art. In the drawings, like numbers refer to like elements throughout. Thicknesses and dimensions of some components may be exaggerated for clarity.

It will be understood that when an element is referred to as being “coupled” or “connected” to another element, it can be directly coupled or connected to the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly coupled” or “directly connected” to another element, there are no intervening elements present. Like numbers refer to like elements throughout. As used herein the term “and/or” includes any and all combinations of one or more of the associated listed items.

As used herein the expression “and/or” includes any and all combinations of one or more of the associated listed items.

This invention is directed to communications connectors, with a primary example of such being a communications jack. As used herein, the terms “forward”, “forwardly”, and “front” and derivatives thereof refer to the direction defined by a vector extending from the center of the jack toward the plug opening of the jack. Conversely, the terms “rearward”, “rearwardly”, and derivatives thereof refer to the direction directly opposite the forward direction; the rearward direction is defined by a vector that extends away from the plug opening toward the remainder of the jack. The terms “lateral,” “laterally”, and derivatives thereof refer to the direction generally parallel with the plane defined by a wiring board on which jack contact wires are mounted and extending away from a plane bisecting the plug in the center. The terms “medial,” “inward,” “inboard,” and derivatives thereof refer to the direction that is the converse of the lateral direction, i.e., the direction parallel with the plane defined by the wiring board and extending from the periphery of the jack toward the aforementioned bisecting plane. Where used, the terms “attached”, “connected”, “interconnected”, “contacting”, “mounted” and the like can mean either direct or indirect attachment or contact between elements, unless stated otherwise. Where used, the terms “coupled,” “induced” and the like can mean non-conductive interaction, either direct or indirect, between elements or between different sections of the same element, unless stated otherwise.

Referring now to the figures, a prior art jack, designated broadly at10, is illustrated inFIGS. 1 and 1A. The jack10includes a jack frame12having a plug aperture14for receiving a mating plug, a cover16and a terminal housing18. These components are conventionally formed and not need be described in detail herein; for a further description of these components and the manner in which they interconnect, see U.S. Pat. No. 6,350,158 to Arnett et al., the disclosure of which is hereby incorporated herein in its entirety. Those skilled in this art will recognize that other configurations of jack frames, covers and terminal housings may also be employed with the present invention. Exemplary configurations are illustrated in U.S. Pat. Nos. 5,975,919 and 5,947,772 to Arnett et al. and U.S. Pat. No. 6,454,541 to Hashim et al., the disclosure of each of which is hereby incorporated herein in its entirety.

In addition, referring still toFIG. 1and also toFIG. 2, the jack10further includes a wiring board20formed of conventional materials. The wiring board20may be a single layer board or may have multiple layers. The wiring board20may be substantially planar as illustrated, or may be non-planar.

Referring again toFIGS. 1 and 1A, contact wires22a,22b,24a,24b,26a,26b,28a,28bare attached to the wiring board20. As described in U.S. Pat. No. 6,350,158 referenced above, the contact wires22a,22b,24a,24b,26a,26b,28a,28bhave free ends that have substantially the same profile, are substantially transversely aligned in side-by-side relationship, and that extend into the plug aperture14to form electrical contact with the terminal blades of a mating plug. The free ends of the contact wires22a,22b,24a,24b,26a,26b,28a,28bextend into individual slots29a–29hin the forward edge portion of the wiring board20. The contact wires22a,22b,24a,24b,26a,26b,28a,28bare arranged in pairs defined by TIA 568B, with wires22a,22b(pair1) being adjacent to each other and in the center of the sequence of wires, wires24a,24b(pair2) being adjacent to each other and occupying the leftmost two positions (from the vantage point ofFIG. 1B) in the sequence, wires28a,28b(pair4) being adjacent to each other and occupying the rightmost two positions (from the vantage point ofFIG. 1B) in the sequence, and wires26a,26b(pair3) being positioned between, respectively, pairs1and4and pairs1and2. The wires22a,22b,24a,24b,26a,26b,28a,28bare mounted to the wiring board20via insertion into respective apertures32a,32b,34a,34b,36a,36b,38a,38b, which are arranged in the illustrated embodiment in a “dual diagonal” pattern known to those skilled in this art as described in U.S. Pat. No. 6,196,880 to Goodrich et al., the disclosure of which is hereby incorporated herein in its entirety. Those skilled in this art will appreciate that contact wires or other contacts of other configurations may be used. As one example, contact wires configured as described in aforementioned U.S. Pat. No. 5,975,919 to Arnett et al. may be employed.

As can be seen inFIGS. 1A and 3, each of pairs1,2and4that comprise adjacent contact wires include a respective “crossover”22c,24c,28c, i.e., a location in which the contact wires of a pair cross each other without making electrical contact, typically such that the free end of one contact wire of the pair is substantially longitudinally aligned with the fixed end portion of the other contact wire of the pair. The crossovers22c,24c,28care located approximately in the center of their contact wires (between the free ends of the contact wires and their mounting locations on the wiring board20). Crossovers are included to provide compensatory crosstalk between contact wires. In the illustrated embodiment, the crossovers are implemented via complementary localized bends in the crossing wires, with one wire being bent upwardly and the other wire being bent downwardly. The presence of a crossover, structural implementations thereof, and its effect on crosstalk are discussed in some detail in the '358 patent described above and U.S. Pat. No. 5,186,647 to Denkmann et al., the disclosure of which is hereby incorporated herein by reference. In this prior art device, the contact wires of pair3(wires26a,26b) do not include a crossover.

Referring once again toFIGS. 1 and 1Aand toFIG. 1B, eight insulation displacement connectors (IDCs)42a,42b,44a,44b,46a,46b,48a,48bare inserted into eight respective IDC apertures52a,52b,54a,54b,56a,56b,58a,58b. The IDCs are of conventional construction and need not be described in detail herein; exemplary IDCs are illustrated and described in U.S. Pat. No. 5,975,919 to Arnett, the disclosure of which is hereby incorporated by reference herein in its entirety.

Referring now toFIGS. 1A,1B and2, the each of the wire apertures32a,32b,34a,34b,36a,36b,38a,38bis electrically connected to a respective IDC aperture52a,52b,54a,54b,56a,56b,58a,58bvia a respective conductor62a,62b,64a,64b,66a,66b,68a,68b, thereby interconnecting each of the contact wires22a,22b,24a,24b,26a,26b,28a,28bto its corresponding IDC42a,42b,44a,44b,46a,46b,48a,48b. The conductors62a,62b,64a,64b,66a,66b,68a,68bare formed of conventional conductive materials and are deposited on the wiring board20via any deposition method known to those skilled in this art to be suitable for the application of conductors. Some conductors are illustrated as being entirely present on a single layer of the wiring board20(for example, conductor62a), while other conductors (for example, conductor62b) may reside on multiple layers of the wiring board20; conductors can travel between layers through the inclusion of vias (also known as plated through holes) or other layer-transferring structures known to those skilled in this art.

U.S. Pat. No. 5,967,853 to Hashim (the disclosure of which is hereby incorporated herein in its entirety) describes a technique whereby capacitive compensation is used to simultaneously compensate differential to differential and differential to common mode crosstalk. However, in order to effectively cancel both NEXT and FEXT it is typically necessary to provide both inductive and capacitive compensation. The prior art arrangement of contact wires disclosed inFIGS. 1–3has been proven to effectively and efficiently provide inductive differential to differential crosstalk compensation. However, it has been determined that this arrangement may be ineffective, and perhaps counterproductive, in providing inductive differential to common mode compensation in the jack10. More specifically, the prior art arrangement provides inductive differential to differential crosstalk compensation between pairs1and3, pairs2and3, and pairs4and3, but in the development of the present invention it has been recognized that, due to the large physical separation between the conductors of pair3and their asymmetric placement relative to pair2(and similarly to pair4), the highest levels of differential to common mode crosstalk in a mating plug, which can be the most problematic to channel performance, tend to occur on pairs2and4when pair3is excited differentially. The differential to common mode crosstalk occurring when any of the pairs1,2and4is excited differentially tends to be much less severe, and consequently much less problematic, because the separation between the conductors in each of these pairs is one-third the separation between the conductors of pair3. In the prior art arrangement of contact wires disclosed inFIGS. 1–3, crossover on each of pairs1,2and4inductively compensates for the less severe differential to common mode crosstalk occurring when any of these pairs is differentially excited. However, due to the absence of a crossover on pair3, this arrangement not only fails to inductively compensate for the more severe common mode crosstalk on pairs2and4when pair3is differentially excited, but can actually exacerbate this problem. This is especially true when the jack receives a conventional plug such as the one illustrated in U.S. Pat. No. 6,250,949 to Lin.

Turning now toFIG. 4, an arrangement of wires according to embodiments of the present invention, designated broadly at120, is illustrated schematically therein. The wiring arrangement120includes eight contact wires122a,122b,124a,124b,126a,126b,128a,128bthat comprise, respectively, wire pairs1,2,3and4. In contrast to the prior art arrangement of contact wires described above, in this embodiment the contact wires122a,122bof pair1, the contact wires124a,124bof pair2, and the contact wires128a,128bof pair4do not include a crossover, while the contact wires126a,126binclude a crossover126c.

Like the prior arrangement, this arrangement of contact wires should provide compensatory inductive differential to differential crosstalk between pairs1and3, pairs2and3, and pairs4and3. In addition, this arrangement, although not inductively compensating for the less severe differential to common mode crosstalk occurring when any of the pairs1,2and4is differentially excited, can provide inductive compensation for the highly problematic differential to common mode crosstalk occurring on pairs2and4when pair3is differentially excited. Because the most problematic differential to common mode crosstalk can be inductively compensated, a jack employing this arrangement can meet higher performance standards, particularly at elevated frequencies.

One exemplary implementation of this arrangement is illustrated and described in co-assigned and co-pending U.S. patent application Ser. No. 11/088,044, filed Mar. 23, 2005, the disclosure of which is hereby incorporated herein in its entirety. The implementation illustrated therein employs supports posts that support the contact wires of pair3as they cross over and under the wires of pair1. However, there may be some manufacturing difficulties with this implementation.

Another exemplary implementation of the arrangement ofFIG. 4is illustrated inFIGS. 5–9, in which a jack200according to embodiment of the present invention is shown. The jack200includes a jack frame212having a plug aperture214, a cover216and a terminal housing218. A wiring board220includes IDCs242a–248bmounted thereon. Conductors222a–228bin the form of contact wires are mounted to the wiring board220in side-by-side and generally parallel relationship. As used herein, “generally parallel” with reference to the conductors means that, from the vantage point ofFIG. 8, substantial portions of the conductors are parallel to one another. Conductors that are “aligned” have free and fixed ends that are substantially collinear from the vantage point ofFIG. 8, and conductors that are “non-aligned” have free and fixed ends that are not substantially collinear from the vantage point ofFIG. 8.

At their free ends, the conductors222a–228bfit within slots229a–229hlocated at the forward end of the wiring board220and are positioned to mate with the blades of a plug inserted into the plug aperture214. With the exception of the crossover region250, described in greater detail below, the conductors222a–228bfollow generally the same profile (from the vantage point ofFIG. 7) until they bend downwardly into their respective mounting apertures in the wire board220. Conductive traces on the wiring board220provide signal paths between the conductors222a–228band the IDCs242a–248b.

Referring now toFIGS. 6–9, the crossover region250includes a “floating” printed wiring board (PWB)251that is suspended above the wiring board220by the conductors222a–228band is generally perpendicular to the wiring board220and the conductors222a–228b. As shown inFIGS. 7 and 7A, the lower edge of the PWB251is spaced apart from the upper surface of the wiring board220, such that the PWB251is free to move upon deflection of the conductors222a–228b(as when a mating plug is inserted into the jack200), although in some embodiments the lower edge of the PWB251may contact the wiring board220, and in other embodiments there may be a clearance opening in the wiring board220to permit the lower edge of PWB251to move to a position below the upper surface of the wiring board220. The distance between the PWB251and the locations where the conductors222a,222bintercept a mating plug is about 0.154 inches, but those skilled in this art will appreciate that a different distance may also be suitable with the present invention. Typically the conductors are between about 0.648 and 0.828 inches in length, and the crossover region250occurs between about 0.3 and 0.4 inches from the free ends of the contact wires222a–228b.

Referring now toFIG. 9, the PWB251, which can be rigid or flexible and is typically formed of a dielectric material, includes eight bores252a,252b,254a,254b,256a,256b,258a,258bin a lower row, and two bores256c,256din an upper row that extend from the front surface251aof the PWB251to the rear surface251bthereof. Six of the conductors, namely those that comprise pairs1,2and4(i.e., conductors222a,222b,224a,224b,228a,228b) pass directly through respective bores252a,252b,254a,254b,258a,258b, and follow relatively straight paths (seeFIGS. 7 and 8). The PWB251is sized such that its lower edge is spaced from the upper surface of the wiring board220(hence the term “floating” PWB). The bores252a,252b,254a,254b,258a,258bare sized such that the conductors passing therethrough can slide relative to the PWB251.

In contrast to the other conductors, each of the conductors226a,226bof pair3includes an approaching segment266a,266bthat veers upwardly from the path defined by the other conductors and passes into a respective bore256c,256dof the upper row of bores. Also, each of the conductors226a,226bincludes an exiting segment286a,286bthat exits a respective bore256a,256band travels therefrom to the wiring board220(each of the exiting segments286a,286bfollows generally the profile of, respectively, the conductors228b,224aas they exit the PWB251). The bores256a,256bare plated with a conductive material. All of the bores256a–256dare sized for a snug fit with their respective segments.

The front surface251aof the PWB251includes a conductive trace276bthat extends between the bore256dof the upper row of bores and the bore256aof the lower row of bores (notably, the path followed by the trace276bcrosses over the conductors222a,222bof pair1). Thus, a conductive path for the conductor226bis created between the approaching segment266b, the conductive trace276b, the bore256a, and the exiting segment286b. Similarly, the rear surface251bof the PWB251includes a conductive trace276athat extends between the bore256cof the upper row of bores and the bore256bof the lower row of bores (and crosses over the conductors222a,222b). Thus, a conductive path for the conductor226ais created between the approaching segment266a, the bore256c, the conductive trace276a, and the exiting segment286a. It can be seen that the conductive traces276a,276bare electrically insulated from each other, which enables the conductors226a,226bto cross without making electrical contact.

It can be seen that the conductive paths of the conductors226a,226b(i.e., the conductors of pair3) are able to “cross over” each other (i.e., the free end of each of the conductors226a,226bof pair3is aligned with the fixed end of the other conductor226b,226aof pair3), and the conductors of pair1in order to create the schematic arrangement shown inFIG. 4. Thus, the illustrated embodiment has the advantage of enabling the commencement of the inductive differential to differential and differential to common mode compensations at minimal delay from the corresponding crosstalk sources, which can be important to effective crosstalk compensation.

It should also be understood that a floating PWB may also be employed for generating cross-over configurations for other pairs of conductors. Furthermore, the floating PWB can be a multi-layer board with the crossover traces residing on any of its layers. It should also be understood that, rather than having selected conductors slide through bores on the floating PWB, any or all of these conductors can comprise approaching and exiting segments that fixedly terminate into plated bores on the PWB, with signal path completion achieved by conductive traces on the PWB or by conductive plating within a single bore. Moreover, it should be recognized that the PWB may be sized such that only the conductors of pairs1and3are captured therein, with the result that the conductors of pairs2and4simply extend unimpeded from free end to fixed end. Alternatively, the PWB and contacts can be sized or shaped such that only the conductors of pair3are captured, with the result that conductors of pairs1,2and4simply extend unimpeded from free end to fixed end. In addition, the PWB may include other devices, such as parallel plate or interdigital capacitors, that provide another stage of capacitive crosstalk compensation.

The skilled artisan will recognize that, although eight contact wires are illustrated and described herein, other numbers of contact wires may be employed. For example, 16 contact wires may be employed, and one or more crossovers that cross over a pair of contact wires sandwiched therebetween may be included in those contact wires.

Further, those skilled in this art will recognize that other jack configurations may also be suitable for use with the present invention. For example, as discussed above, other configurations of jack frames, covers and terminal housings may also be employed with the present invention. As another example, the contact wires may have a different profile (an exemplary alternative profile is depicted in U.S. Pat. No. 5,975,919 to Arnett et al.), or they may mount in locations that do not follow the “dual diagonal” mounting scheme illustrated herein (an exemplary alternative in which the contact wires are staggered is illustrated in U.S. Pat. No. 6,116,964 to Goodrich et al). As a further example, the IDCs may mount in a different pattern on the wiring board, or some other type of connector may be used. Those skilled in this art will also recognize that embodiments of the wiring board described above may be employed in other environments in which a communications jack may be found. For example, jacks within a patch panel or series of patch panels may be suitable for use with such wiring boards. Other environments may also be possible.

The configuration illustrated and described herein can provide connectors, and in particular communications jacks, that exhibit improved crosstalk characteristics, particularly at elevated frequencies. For example, a connector such as that illustrated inFIGS. 5–9and mated with a conventional plug may have channel alien NEXT of less than −60 dB power sum at 100 MHz, and less than −49.5 dB power sum at 500 MHz.

Also those skilled in the art will recognize that, in situations in which it may not be critical to implement the differential to differential crosstalk compensation between pairs3and2and between pairs3and4in the contact wires, it is possible to provide instead compensation for the common mode crosstalk induced on pair3, or pair1, when either of pair2or pair4is differentially excited, by modifying the contact wire crossover scheme ofFIG. 4to include crossovers in pairs2and4in addition to the crossover on pair3.

Further, those skilled in the art will recognize the reciprocity that exists between the differential to common mode crosstalk induced on a first pair, when a second pair is excited differentially, and the common mode to differential signal induced on the second of these pairs when the first of these pairs is excited common-modally, with the common mode to differential crosstalk equaling the differential to common mode crosstalk multiplied by a constant, that constant being the ratio of the differential to common mode impedances. Consequently, when an improvement occurs, due to the current invention, in the differential to common mode crosstalk between two pairs when one of these pairs is excited differentially, a corresponding improvement occurs in the common mode to differential crosstalk between these two pairs, when the other of these pairs is excited common-modally.