Patent Application
20090191740
1. Technical Field
The present disclosure is directed to modular insert assemblies and, more particularly, to modular insert assemblies that include bi-sectional contacts that allow interrupted communications across individual contacts, e.g., based upon interaction with corresponding plug contacts.
2. Background Art
Devices for interfacing with high frequency data transfer media are generally known. Modular jack housing inserts have been developed that facilitate interface with connectors, i.e., plugs, that in turn interact with unshielded twisted pair (UTP) media. UTP media finds widespread application in structured cabling applications, e.g., in local area network (LAN) implementations and other in-building voice and data communications applications. In a UTP cable, a plurality of twisted copper pairs are twisted together and wrapped with a plastic coating. Individual wires generally have a diameter of 0.4-0.8 mm. Twisting of the wires increases the noise immunity and reduces the bit error rate (BER) associated with data transmission thereover. Also, using two wires rather than one to carry each signal permits differential signaling to be used, which offers enhanced immunity to the effects of external electrical noise.
As an alternative to UTP media, shielded twisted pair (STP) media is used in certain structured cabling applications. STP media includes shielding, e.g., a foil or braided metallic covering, that generally reduces the effects of outside interference. However, as compared to STP media, UTP media offers reduced cost, size and cable/connector installation time. In addition, the use of UTP media, as opposed to STP media, eliminates the possibility of ground loops (i.e., current flowing in the shield because the ground voltage at each end of the cable is not exactly the same, thereby potentially inducing interference into the cable that the shield was intended to protect). In short, UTP media is a flexible, low cost media having widespread application in voice and/or data communications.
The wide acceptance and use of UTP for data and voice transmission is also driven by the large installed base, low cost and ease of new installations. Another important feature of UTP is that it can be used for varied applications, such as for Ethernet, Token Ring, FDDI, ATM, EIA-232, ISDN, analog telephone (POTS), and other types of communication. This enables the same type of cable and system components (such as jacks, plugs, cross-patch panels and patch cables) to be used for an entire building installation, unlike STP media.
UTP media is being used for systems having increasingly higher data rates. In data transmission, the signal originally transmitted through the data transfer media is not necessarily the signal received. The received signal will consist of the original signal as modified by various distortions and additional unwanted signals introduced over the transmission path. Such distortions and unwanted signals affect the original signal between transmission and reception and are commonly collectively referred to as “electrical noise” or simply “noise.” Noise can be a primary limiting factor in the performance of a communication system. Indeed, many problems may arise from the existence and/or introduction of noise during data transmission, such as data errors, system malfunctions and loss of the original signals (in whole or in part).
The transmission of data by itself causes unwanted noise. Electromagnetic energy, induced by the electrical energy in the individual signal carrying lines within the data transfer media and data transfer connecting devices, radiates onto adjacent lines in the same media or device. This cross coupling of electromagnetic energy (i.e., electromagnetic interference or EMI) from a “source” line to a “victim” line is called crosstalk. Most data transfer media consist of multiple pairs of lines bundled together. Communication systems typically incorporate many such media and connectors for data transfer. Thus, there exists an opportunity for significant crosstalk interference.
Electromagnetic energy waves can be derived by Maxwell's wave equations. These equations are basically defined using electric and magnetic fields. In unbounded free space, a sinusoidal disturbance propagates as a transverse electromagnetic wave. This means that the electric field vectors are perpendicular to the magnetic field vectors lying in a plane perpendicular to the direction of the wave. Crosstalk results in a waveform shaped differently than the one originally transmitted.
Crosstalk can be categorized in one of two forms. Near end crosstalk, commonly referred to as NEXT, arises from the effects of near field capacitive (electrostatic) and inductive (magnetic) coupling between source and victim electrical transmissions. NEXT increases the additive noise at the receiver and therefore degrades the signal to noise ratio (SNR). NEXT may be the most significant impediment to effective data transfer because the high-energy signal from an adjacent line can induce relatively significant crosstalk into the primary signal. A second form of crosstalk is far end crosstalk (FEXT) which arises due to capacitive and inductive coupling between the source and victim electrical devices at the far end or opposite end of the transmission path. FEXT is typically less of an issue because the far end interfering signal is attenuated as it traverses the loop.
Another major source of distortion for high speed signal transmission may be mismatch of transmission impedances. As the signal travels along transmission media, various interconnections are generally encountered. Each interconnection has its own internal impedance relative to the traveling signal. For UTP cabling, the transmission media impedance is generally 100 Ohms. Any offsets or differences in impedance values from connecting devices will produce signal reflections. Generally, signal reflections reduce the amount of transmitted signal energy to the receiver and/or distort the transmitted signal. Thus, signal reflections can lead to an undesirable increase data loss.
To accommodate higher frequency data communications, commercially available connection systems generally include compensation functionality that is intended to compensate for electrical noise, e.g., noise/crosstalk introduced in the connection assembly or assemblies. Since demands on networks using UTP systems (e.g., 100 Mbit/s, 1200 Mbit/s transmission rates and higher) have increased, it has become necessary to develop industry standards for higher system bandwidth performance. What began as simple analog telephone service and low speed network systems, has now become high speed data systems. As the speeds have increased, so has the noise.
The ANSI/TIA/EIA 568A standard defines electrical performance for systems that operate in the 1-100 MHz frequency bandwidth range. Exemplary data systems that utilize the 1-100 MHz frequency bandwidth ranges are IEEE Token Ring, Ethernet10Base-T and 100Base-T systems. Five performance categories have been defined by ANSI/TIA/EIA-568.2-10 and the subsequent ANSI/TIA/EIA-568B.2 promulgations, as shown in the Table 1 below. Compliance with these performance standards are used, inter alia, to identify cable/connector quality.
UTP cable standards are also specified in the EIA/TIA-568 Commercial Building Telecommunications Wiring Standard, and such standards include electrical and physical requirements for UTP, STP, coaxial cables and optical fiber cables. For UTP, the requirements include (i) four individually twisted pairs per cable, (ii) each pair has a characteristic impedance of 100 Ohms +/−15% (when measured at frequencies of 1 to 100 MHz); and (iii) 24 gauge (0.5106-mm-diameter) or optionally 22 gauge (0.6438 mm diameter) copper conductors are specified. Additionally, the ANSI/TIA/EIA-568 standard specifies the color coding, cable diameter and other electrical characteristics, such as the maximum cross-talk (i.e., how much a signal in one pair interferes with the signal in another pair—through capacitive, inductive and other types of coupling).
The Category 5 cabling systems provided sufficient NEXT margins to allow for the high NEXT that occurs when using the present UTP system components. However, the demand for higher frequencies, more bandwidth and improved system performance (e.g., Ethernet 1000Base-T) for UTP cabling systems required enhanced system design/performance. More particularly, the TIA/EIA Category 6 standard extended performance requirements to frequency bandwidths of 1 to 250 MHz, requiring minimum NEXT values at 100 MHz to be −39.9 dB and −33.1 dB at 250 MHz for a channel link, and minimum NEXT values at 100 MHz to be −54 dB and −46 dB at 250 MHz for connecting hardware. The increased bandwidth accommodated by the Category 6 standard required increased focus on noise compensation.
More recently, the TIA/EIA 568 Category 6A addendum 10 or EIA568B.2-10 for a new Augmented Category 6 cabling standard extends performance requirements to still higher frequencies, i.e., frequency bandwidths of 1 to 500 MHz. More particularly, the addendum specifies (i) minimum NEXT values at 100 MHz to be −39.9 dB and −26.1 dB at 500 MHz for a channel link, and (ii) minimum NEXT values at 100 MHz to be −54 dB and −34 dB at 500 MHz for connecting hardware. The requirements for Return Loss for a channel are −12 dB at 100 MHz and −6 dB at 500 MHz, and for a connector the corresponding requirements are −28 dB at 100 MHz and −14 dB at 500 MHz.
As noted above, a key element for compensation of NEXT and FEXT is the design and operation of the electrical interface, e.g., the electrical communication between jack and plug connectors. The standard modular jack housing is configured and dimensioned in compliance with the FCC part 68.500 standard which provides compatibility and matability between various media manufacturers. The standard FCC part 68.500 style for modular jack housing which does not add compensation methods/functionality to reduce crosstalk. This standard modular jack housing provides a straightforward approach/design and, by alignment of lead frames in a parallel, uniform pattern, high NEXT and FEXT are generally produced for certain adjacent wire pairs. More particularly, the standard FCC part 68.500 modular jack housing connector defines two lead frame section areas. Section one defines a matable area for electrical plug contact and section two is the output area of the modular jack housing. Section one aligns the lead frames in a parallel, uniform pattern from lead frame tip to the bend location that enters section two, thus producing relatively high NEXT and FEXT noises. Section two also aligns the lead frames in a parallel, uniform pattern from lead frame bend location to lead frame output, thus producing/allowing relatively high NEXT and FEXT noises.
There have been efforts aimed at reducing crosstalk through modified housing designs. For example, U.S. Pat. No. 6,139,371 to Troutman et al. discloses a communication connector assembly having a base support and first and second pairs of terminal contact wires with base portions mounted on the base support. The free end portions of the contact wires define a zone of contact within which electrical connections are established with a mating connector, and each pair of contact wires defines a different signal path in the connector assembly. The first and the second pair of contact wires have corresponding leading portions extending from the free end portions to a side of the zone of contact opposite from the base portions. A leading portion of a contact wire of the first pair and a leading portion of a contact wire of the second pair are constructed and arranged for capacitively coupling to one another, thus conveying capacitive crosstalk compensation to the zone of contact where offending crosstalk is introduced by a mated connector. The additional coupling of the Troutman '371 patent is inadequate in reducing crosstalk to a required degree because, inter alia, the elongated plates are crossed/overlapped and also adjacent, thus creating unwanted parallelisms between contacts 3 to 4 and contacts 5 to 6 and undesirably increasing crosstalk noises. Although crosstalk noise may be reduced by the design of the Troutman '371 patent, the effective complex modes of coupling are more than doubled which potentially increases NEXT, FEXT and noise variation factors.
A similar approach to crosstalk reduction is disclosed in U.S. Pat. No. 6,332,810 to Bareel. The Bareel '810 patent discloses an electrical connector having irregular bends the lead frames and coupling plates defined on contacts 1, 3, 4, 5, 6 and 8. With reference to
Another similar approach to reducing crosstalk noises associated with a modular jack housing is disclosed in U.S. Pat. No. 6,409,547 to Reede. The Reede '547 patent discloses an electrical connector that includes bent cantilever spring beams having ends that are electrically connected to capacitive plates. Although crosstalk noise may be reduced, spring beam contacts can increase unwanted coupling due to their lengths.
U.S. Pat. No. 6,176,742 to Arnett et al. discloses an electrical connector that provides capacitive crosstalk compensation coupling in a communication connector by the use of a capacitor compensation assembly. One or more crosstalk compensation capacitors are supported in the housing. Each compensation capacitor includes a first electrode having a first terminal, a second electrode having a second terminal, and a dielectric spacer disposed therebetween. The terminals of the electrodes are exposed at positions outside of the housing so that selected terminal contact wires of the connector make electrical contact with corresponding terminals of the compensation capacitors to provide capacitive coupling between the selected contact wires when the contact wires are engaged by a mating connector. Of note, a design of the type disclosed in the Arnett '742 patent can undesirably decrease contact flexibility, thereby adds complexity to design efforts. In addition, utilizing a curved spring beam contact design can increase unwanted NEXT/FEXT noises because of the adjacencies between pairs.
U.S. Pat. No. 6,443,777 to McCurdy et al. discloses a communication jack having a first and second pairs of contact wires defining corresponding signal paths in the jack. Parallel, co-planar free end portions of the wires are formed to connect electrically with a mating connector that introduces offending crosstalk to the signal paths. First free end portions of the first pair of contact wires are supported adjacent one another, and second free portions of the second pair are supported adjacent corresponding ones of the first free end portions. Intermediate sections of the first pair of contact wires diverge vertically and traverse one another to align adjacent to corresponding intermediate sections of the second pair of wires to produce inductive compensation coupling to counter the offending crosstalk from the plug. Capacitive compensation coupling may be obtained for the contact wires via one or more printed wiring boards supported on or in the jack housing.
Another method for crosstalk noise reduction and control in connecting hardware is addressed in commonly assigned U.S. Pat. No. 5,618,185 to Aekins. A connector for communications systems includes four input terminals and four output terminals in ordered arrays. A circuit electrically couples respective input and output terminals and cancels crosstalk induced across adjacent connector terminals. The circuit includes four conductive paths between the respective input and output terminals. Sections of two adjacent paths are in close proximity and cross each other between the input and output terminal. At least two of the paths have sets of adjacent vias connected in series between the input and output terminals. The subject matter of the Aekins '185 patent are hereby incorporated by reference.
Alternative conductor layouts for purposes of jack/plug combinations have been proposed. For example, U.S. Pat. No. 6,162,077 to Laes et al. and U.S. Pat. No. 6,193,533 to De Win et al. disclose male/female connector designs wherein shielded wire pairs are arranged with a plurality of side-by-side contacts and additional contact pairs positioned at respective corners of the male/female connector housings. The foregoing arrangement of contacts/contact pairs for shielded cables is embodied in an International Standard—IEC 60603-7-7—the contents of which are hereby incorporated herein by reference. The noted IEC standard applies to high speed communication applications with 8 position, pairs in metal foil (PIMF) shielded, free and fixed connectors, for data transmissions with frequencies up to 600 MHz.
Despite efforts to date, a need remains for connector designs that reliably and effectively address the potential for crosstalk noise, e.g., at higher transmission frequencies. In addition, a need remains for connector designs that accommodate plugs of varying design/contact layout. Still further, a need remains for connector designs that compensate for crosstalk without adding undue complexity and/or potential cost to the connector design and/or manufacture. Moreover, a need remains for connector designs that accommodate and/or facilitate the introduction or non-introduction of compensation as may be desired based on variable factors encountered in use, e.g., different plug designs and/or plugs having differing contact layouts.
These and other needs are satisfied by the systems and connector designs disclosed herein, as will be apparent from the detailed description which follows, particularly when read in conjunction with the figures appended hereto.
The present disclosure is directed to advantageous modular insert assemblies and, more particularly, to modular insert assemblies that include bi-sectional contacts that allow interrupted communications across individual contacts, e.g., based upon interaction with corresponding plug contacts. According to exemplary embodiments of the present disclosure, lead frame wires or contacts having split, bi-sectional or dual forms are positioned in a connector housing, e.g., a jack housing, so as to accommodate electrical interface with contacts in a connecting assembly, e.g., a plug. The split/bi-sectional lead frame wires/contacts may feature desired geometries, e.g., through bending or the like, so as to reduce noise and rebalance the signal pairs in a simple and low cost manner, and without altering the impedance characteristics of the wire pairs.
In an exemplary embodiment of the present disclosure, a modular dielectric insert for a modular jack housing for use in data/voice communication systems is provided. The disclosed insert advantageously functions to reduce NEXT and FEXT. Moreover, the disclosed insert allows optional contact between bi-sectional/split contacts associated therewith, thereby controlling compensation introduction and/or delivery based on, inter alia, the design/layout of an associated plug to be associated therewith. Thus, the disclosed insert allows and/or facilitates optional delivery of compensation based on multiple preformed reactance parameters within the split wire paired units.
In exemplary embodiments, the disclosed telecommunication connector system is designed to optionally reduce electro magnetic interference from an adjacent transmitter. The optional reduction of EMI is achieved through connecting hardware design. The internal contacts are isolated and split into two-sectional design. Internal EMI line reduction is allowed/introduced only when the two sectional contacts are electrically mated by an outside source. By isolating the contact sections in the interface system, the coupled signal for EMI balance is optionally utilized in a low cost and manufacturable design. Thus, the disclosed split/bi-sectional design functions as an internal passive switch method for the introduction of signal noise balancing as and when appropriate.
The disclosed bi-sectional/split contact design also provides reliable functionality over an extended period. Thus, for example, a modular jack dielectric insert device that includes the disclosed bi-sectional/split contact design, e.g., for use in data/voice systems, reduces the potential for wire pair deformation, e.g., in a standard EIA T568B style wire configuration. Each of the bi-sectional/split contact members advantageously define elongated cantilever members that are supported by the jack housing, with the cantilevered portions thereof extending into a spaced, side-by-side position. Deflection of one or both cantilevered members is effective to complete a circuit associated with the bi-sectional/split contact members. Such deflection is generally effectuated through introduction of a plug into the jack housing, with bi-sectional contacts being brought into contact only insofar as the plug has a contact member that is brought into alignment/contact with a particular bi-sectional/split contact. The design is thus simple, low cost and easy to implement into a modular housing.
In an exemplary embodiment, the disclosed insert is positioned within a modular jack housing such that the associated contacts are positioned for electrical communication with data signal transmission media plug elements/contacts introduced to the receiving space of the jack housing. The insert generally includes a dielectric support member having a plurality of pairs of substantially straight elongated contact members positioned in contact therewith. One or more of the substantially straight, elongated members are split into two separated and initially electrically open contacts. The front end section(s) of the split/bi-sectional contact(s) are typically substantially straight, elongated members that have a front end portion which includes a contact portion that is exposed in the receiving space of the modular housing for making electrical contact with the media plug contacts.
The front end sections of one or more of the split/bi-sectional contact(s) also advantageously communicate with a capacitive coupling section. The capacitive coupling section may take a variety of forms. Thus, in a first exemplary embodiment, the capacitive coupling section takes the form of capacitive plates in a side-by-side position/orientation that are in electrical communication with transmission media requiring compensation. In a second exemplary embodiment, the capacitive coupling section may take the form of interdigitated fingers/extensions in electrical communication with transmission media requiring compensation. In a further exemplary embodiment, the capacitive coupling region may be defined on a printed circuit board (PCB) in electrical communication with transmission media requiring compensation. Thus, the PCB may feature closely aligned traces, via's, interdigitated stub regions and/or ancillary electronic components (e.g., capacitors) for effecting a desired level of compensation.
The rear end section of exemplary split/bi-sectional contacts according to the present disclosure generally include an electrically conductive connector device/region for connecting and transmitting a signal to other devices. Thus, for example, the rear end sections may define or cooperate with extensions that are adapted to engage a printed circuit board (PCB) or otherwise communicate with associated devices/assemblies.
Thus, in one aspect in accordance with the present disclosure, the pluralities of pairs of elongated members have substantially multilaterally symmetrical portions and substantially multilaterally asymmetrical portions. In another aspect, the internal contacts are isolated and split into a two-sectional design. By isolating or splitting each contact section in the interface system, the coupled signal for EMI balance is optionally implemented by and based upon the modular plug that is inserted for electrical connection. In a further aspect, the front end portions of the front section elongated conductive members are in electrical communication with frontal capacitive coupling functionality that is preformed and/or combined therewith, the capacitance field defined thereby functioning to rebalance and/or reduce crosstalk associated with central pair contact combinations.
In another aspect in accordance with the present disclosure, each pair of the plurality of pairs of elongated members includes a ring member and a tip member. The ring and tip members may be separated so that the ring members are on the same plane, that is, in one row, and the tip members are in another row. Preferably, these rows of conductors are spaced apart.
Preferably, the disclosed insert is used in a modular jack that is adapted to receive and compensate signals transmitted through the eight leads from plugs of differing design/layout. Thus, the disclosed insert/jack is first adapted to receive and compensate signals from a standard RJ45 plug. The EIA T568B has eight positions numbered 1-8 which are paired as follows: 1-2 (pair 2), 3-6 (pair 3), 4-5 (pair 1), 7-8 (pair 4). For the EIA T568B or T568A style configurations of category 6 and 6A UTP cabling, and most others, there are also eight positions. Thus, there are eight elongated conductive elements disposed on the dielectric support member. Again, each front end section of each bi-sectional/split element has a front portion with a contact portion for establishing electrical contact with one of the eight leads. Such contact causes deflection of the front end section into electrical communication with the rear end section of the bi-sectional/split contact. The rear end sections are generally adapted to effect further transmission of the signal from the front end to the terminal end.
Exemplary embodiments of the disclosed insert/jack are also advantageously adapted to receive and compensate signals from a plug that is configured according to the IEC 60603-7-7 standard (see, e.g., U.S. Pat. Nos. 6,162,077 and 6,193,533). In such plug design, pairs of contacts are positioned substantially in the four corners thereof. To accommodate such plug design, the disclosed jack includes eight (8) bi-sectional/split contacts in side-by-side alignment so as to accommodate an RJ-45 plug (as described above), and an additional two (2) pairs of contacts in opposed/spaced corners of the jack that are adapted to cooperate with corresponding contacts formed in the noted plug. Thus, when a plug that is compliant with the IEC 60603-7-7 standard is introduced to the disclosed jack, the central four (4) bi-sectional/split contacts of the eight side-by-side contacts do not make contact with corresponding contacts within the plug.
The dual functionality of the disclosed jack, i.e., the ability to automatically accommodate plugs of differing contact layout, is particularly advantageous. Of note, but for the bi-sectional/split contact arrangement of the disclosed insert/jack, the central pairs would contribute/introduce compensation to the circuit by reason of the capacitive plates/interdigitated fingers/PCB compensation in communication with the front ends thereof. However, by reason of the bi-sectional/split contact design disclosed herein, such compensation does not arise and the compensation functionality is effectively isolated from the transmission media when and to the extent a plug does not include an aligned contact for a bi-sectional/split contact within the jack.
These conductive elements are arranged in a positional relationship with respect to each other for forming a capacitance to compensate electrical noise during transmission of the signal. The positional relationship may involve having the front portions of the eight conductive elements with dual coupling sections in a substantially parallel alignment along two longitudinal axes, and having the rear portions include parallel portions as well as portions transverse to the longitudinal axis.
According to the present disclosure, an arrangement for compensating crosstalk noise is provided that includes a dielectric modular jack housing having a signal transmission media receiving space for receiving signal transmission media having a plurality of conductive members, such as a UTP cable and plugs. Pluralities of pairs of conductors are disposed in the signal transmission media receiving space. The conductors are split into two halves/portions, front and rear end contact sections. The front end contact section is adapted to mate with, i.e., make electrical contact with, a contact of a mating plug. In addition, upon mating with a plug having an aligned contact, the front end portion and the rear end portion are brought into electrical contact, e.g., based on deflection of at least the front end portion into contact with the rear end portion.
For compensation purposes, once a forward location of the rear end section is brought into electrical contact with the front end portion, e.g., based on deflection as described herein, the rear end section (and the transmission media as a whole) receives compensation signal(s) from the compensation region associated with the front end portion, e.g., from compensation functionality associated with a printed circuit board (“PCB”) in communication with the front end portion.
In accordance with exemplary embodiments of the present disclosure, the elongated conductors positioned within the jack housing may be placed in a positional relationship with respect to each other to impart a capacitance effect for compensating electrical noise in a signal transmission. The capacitive positional relationship may involve, inter alia, the front end portions being substantially parallel with respect to each other along two longitudinal axes, with each section being non-adjacent to each other. Alternatively or in addition, the rear end portions may be partially parallel to form another coupling section (and partially transverse with respect to the axis).
These and other unique features of the disclosed systems, apparatus and methods will become more readily apparent from the following description, particularly when read in conjunction with the appended figures.
So that those having ordinary skill in the art to which the subject disclosure appertains will more readily understand how to construct and employ the systems, apparatus and methods of the subject disclosure, reference may be had to the drawings wherein:
The present disclosure provides advantageous modular insert assemblies for use in voice/data communication systems. The present disclosure also provides jack assemblies that include such insert assemblies, and jack/plug combinations that benefit from the advantageous structures, features and functions disclosed herein. In addition, the present disclosure provides methods for effecting voice/data communications wherein modular insert assemblies, jacks containing the disclosed insert assemblies and/or jack/plug combinations as described herein, are advantageously employed.
The disclosed modular insert assemblies include one or more bi-sectional contacts that define two distinct states: (i) an “open” state where the front end portion of a bi-sectional contact is spaced from and not in electrical communication with a rear end portion of such bi-sectional contact, and (ii) a “closed” state where the front end portion of the bi-sectional contact is in contact with, and therefore in electrical communication with, the rear end portion of such bi-sectional contact. The front and rear end portions are advantageously mounted with respect to an underlying insert member such that the “open” state is maintained unless and until a plug having an aligned contact is brought into engagement with a jack containing such insert assembly.
The disclosed bi-sectional/split contact design provides reliable functionality over an extended period by, inter alia, reducing the potential for wire pair deformation, e.g., in a standard EIA T568B style configuration. Each of the bi-sectional/split contact members advantageously define elongated cantilever members that are supported by the insert and/or jack housing, with the cantilevered front end and rear end portions thereof extending into a spaced, side-by-side (i.e., “open” state) position. Deflection of one or both cantilevered members is effective to complete a circuit associated with the bi-sectional/split contact members, e.g., through engagement with a corresponding plug contact.
The bi-sectional/split contacts generally take the form of lead frames, although the present disclosure is not limited to lead frame implementations. In exemplary embodiments wherein the bi-sectional/split contacts are fabricated as lead frames, such lead frames are typically positioned in an insert member for subsequent positioning in a jack housing. Once assembled in a jack housing, the bi-sectional contacts/lead frames facilitate electrical interface and communication with contacts in a connecting assembly, e.g., a plug. Noise reduction may be provided by the geometric features and/or positional relationship of individual lead frames, as is known in the art. In addition, pairs of lead frame members are typically associated with capacitive structure(s) to provide further noise reduction and/or compensation.
The disclosed insert is typically positioned within a modular jack housing such that the associated contacts/lead frames are positioned for electrical communication with data signal transmission media plug elements/contacts introduced to the receiving space of the jack housing. The insert generally includes a dielectric support member in which a plurality of pairs of substantially straight, elongated contact members/lead frames are positioned. As noted herein, one or more of the contact members/lead frames define bi-sectional/split structures that each include a front end portion and a rear end portion. The front end portions/sections of one or more of the split/bi-sectional contact(s) also advantageously communicate with a capacitive structure, e.g., a capacitive coupling section. The rear end portions may also communicate with a printed circuit board (PCB) that includes compensation functionality, e.g., capacitively aligned traces, capacitive stub regions, capacitively positioned via's, or the like.
The capacitive coupling section in communication with the front end portions of the bi-sectional contacts/lead frames may take a variety of forms, e.g., capacitive plates in a side-by-side position/orientation, interdigitated fingers/extensions and/or a printed circuit board (PCB) that includes closely aligned traces, capacitively positioned via's, interdigitated stub regions, and/or ancillary electronic components (e.g., capacitors).
The disclosed insert is advantageously used in a modular jack that is adapted to receive and compensate signals transmitted through the eight leads from plugs of differing design/layout. Thus, the disclosed insert/jack is first adapted to receive and compensate signals from a standard RJ45 plug. The disclosed insert/jack is also advantageously adapted to receive and compensate signals from a plug that is configured according to the IEC 60603-7-7 standard (see, e.g., U.S. Pat. Nos. 6,162,077 and 6,193,533). Based on the significant spacing of contact pairs according to the IEC 60603-7-7 standard, crosstalk is substantially reduced. Thus, lesser amounts of compensation are required for plug/jack assemblies according to the IEC 60603-7-7 standard as compared to a conventional RJ-45 plug/jack combination.
The disclosed insert/jack design is advantageously adapted to deliver an appropriate level of compensation, regardless of the contact arrangement of the plug (i.e., whether the plug features an RJ-45 alignment or a contact arrangement according to the IEC 60603-7-7 standard). Thus, when an RJ-45 plug is inserted/combined with a disclosed insert/jack, all eight (8) bi-directional contacts/lead frames deflect to the “closed” state, thereby drawing upon the capacitive structure(s) in communication with the front end portions of appropriate lead frames/contacts, e.g., the central four (4) lead frames/contacts. Conversely, when a plug that is compliant with the IEC 60603-7-7 standard is introduced to the disclosed jack, the central four (4) lead frames/contacts do not make contact with corresponding contacts within the plug. As such, the capacitive structure(s) in communication with the front end portions thereof are isolated from the circuit, and the only compensation delivered to the central four (4) lead frames/contacts is that compensation associated with the PCB in communication with the rear end portions of such lead frames/contacts. The dual functionality of the disclosed jack, i.e., the ability to automatically accommodate plugs of differing contact layout, is particularly advantageous.
Referring now to the drawings,
Insert 10 supports the eight (8) lead frames in accordance with most standard wiring formations, thereby accommodating RJ45 plugs according to as the T568B and T568A standards. The TIA/EIA commercial building standards have defined category 5e to 6A electrical performance parameters for higher bandwidth (100 up to 500 MHz) systems. In category 5e and 6A, the TIA/EIA RJ45 wiring style is currently preferred and is followed throughout the cabling industry. However, as described in greater detail below, a jack that receives insert 10 according to the present disclosure includes an additional two (2) pairs of contacts in opposed corners, thereby also accommodating plugs having contact geometries in compliance with the IEC 60603-7-7 standard. Such additional contact pairs are generally not supported by insert 10, although alternative insert geometries may be developed/adopted to accommodate twelve (12) lead frame/contact pairs in the alignment schematically depicted in
The rear sections of lead frames 16 through 30 are thus engaged or captured in channel slots 32. In an exemplary embodiment of the present disclosure, such engagement/capture is effectuated through interaction between T-shaped cut outs 32 formed in upper portion 12 and/or lower portion 14 to receive corresponding T-shaped features (see, e.g., T-shaped portions 20a, 24a in
With reference to
With reference to
In exemplary embodiments of the present disclosure, the capacitive pads/plates 113, 115 associated with lead frames 20, 24 may be positioned slightly below the capacitive pads/plates 114, 116 associated with lead frames 22, 26 so as to reduce and/or avoid unwanted stray capacitive coupling. Insert housing 11 advantageously functions to maintain each of the capacitive pads/plates 113, 114, 115, 116 in a desired vertical and horizontal orientation, thereby ensuring proper capacitive functionality for the disclosed capacitive structures.
The design and operation of capacitive pads/plates 113-116 to deliver an appropriate level of compensation to insert 10 is within the skill level of ordinary practitioners in the field. The capacitive contributions from capacitive pads/plates 113-116 must be balanced with other compensation contributors associated with the overall design and operation of the disclosed jack. Thus, for example, any compensation generated by the PCB in electrical communication with the rear end portions and/or compensation generated by geometric arrangement of the lead frames as they traverse insert 10 must be considered in sizing and orienting capacitive pads/plates 113-116 so as to offset the noise introduced by reason of the plug/jack interconnection.
Lead frames 16 through 30 traverse insert 10 from outer end 38 to inner end 40 and, for a portion of the distance, may be substantially parallel with respect to each other. According to the exemplary embodiments of the present disclosure, outer lead frame pairs 16, 18 and 28, 30 define continuous structures, i.e., lead frames 16, 18, 28, 30 are not bi-sectional/split lead frames. However, in alternative embodiments, such outer lead frame pairs may be fabricated as bi-sectional/split lead frames without departing from the spirit or scope of the present disclosure. In such circumstance, to the extend ancillary components and/or circuitry is in electrical communication with front end portions of the bi-sectional, outer lead frame pairs, such ancillary components and/or circuitry would be isolated from the circuit and/or signals traveling on such outer lead frame pairs unless and until a “closed” state was effected.
Outer lead frame pairs 16, 18, 28, 30 are elongated contacts with curved or bent body portions that define upstanding contact portions for effecting electrical contact with an inserted plug. The contact portions may be bowed or otherwise upwardly extending so as to facilitate effective electrical contact with corresponding contacts formed in a plug. Connector pins extend from the inner end of all lead frames, including specifically outer lead frame pairs 16, 18, 28,30, to permit mating of such lead frames with other components or cables, e.g., a PCB. In the contact region, all lead frames 16 through 30 are typically aligned in a substantially parallel, spaced orientation so as to facilitate electrical communication/engagement with a plug's contacts, e.g., an RJ45 plug of the type schematically depicted in
As noted previously, the central lead frame pairs 20, 22, 24, 26 are split into two sections according to exemplary embodiments of the present disclosure. Based on the forces to be encountered when a plug is inserted (or withdrawn) from a jack containing insert 10, the front end portions 20a, 22a, 24a, 26a generally overlay the corresponding rear end portions 20b, 22b, 24b, 26b. Upon mating with a plug that includes aligned contacts, the front end portions 20a, 22a, 24a, 26a of lead frames 20, 22, 24, 26 are deflected downward into contact/engagement with rear end portions 20b, 22b, 24b, 26b, thereby establishing electrical communication therebetween. In this way, the capacitive structures, i.e., capacitive pad/plate pairs 113, 115 and 114, 116, are energized and generate compensation signals for delivery to lead frame contacts 20, 22, 24, 26.
Referring again to
In exemplary embodiments of the present disclosure, lead frames 30, 26, 22, 18 are designated ring R′ (i.e., negative voltage transmission) polarity and lead frames 28, 24, 20, 16 are designated tip T′ (i.e., positive voltage transmission) polarity. For T568B category 5e and 6 frequencies, unwanted noise is induced mainly between contacts 26, 24, 22, 20, and minor unwanted noises are introduce between contacts 18 and 20 as well as contacts 26 and 28.
Lead frames 16 through 30 are electrically short in reference to the wavelengths up to 500 MHz. By positioning the capacitive structures, e.g., capacitive pads/plates 113, 115 and 114, 116, in close proximity to the source of the crosstalk noise, the offset regions are reduced. Re-balancing the original signal to remove the noise signal is best achieved by using a signal of opposite polarity than the originating noise signal. The optimal point for creation of a re-balancing signal is within 0.2 inches of the noise creation region because it provides equal magnitude and phase to the original negative noise region, among other things. The disclosed insert assemblies are advantageously effective in satisfying or approaching this desired proximity.
Lead frames 16 through 30 are generally arranged in a manner to reduce unwanted noise via coupling in EIA RJ45 T568B having standard plug positions 1, 2, 3, 4, 5, 6, 7, 8, particularly as compared to standard RJ45 modular inserts. This reduction in unwanted noise generation is achieved, in part, by reducing the degree to which lead frame are maintained in a parallel/adjacent orientation as compared to standard RJ45 modular inserts.
More fundamentally, however, by splitting at least the central lead frame pairs, i.e., lead frames 20, 22, 24, 26, into two distinct, separated portions, the disclosed inserts, jacks and assemblies function effectively whether a plug to be mated with the disclosed insert/jack includes all standard contacts of an EIA RJ45 T568B plug, or does not include such central lead frame pairs, e.g., as is the case with a plug fabricated in accordance with the IEC 60603-7-7 standard. In such case, the center contacts 3, 4, 5, 6 are removed and are repositioned in opposed corner locations and, according to the advantageous bi-sectional/split lead frame design of the present disclosure, the “closed” state is not achieved for such central lead frame pairs. Therefore, the capacitive structures associated with the front end portions of lead frames 20, 22, 24, 26 would not be energized and noise balancing therefrom would not arise. Engagement and energizing of the compensation functionality associated with the lead frames 20, 22, 24, 26 only occurs when the disclosed insert/plug is mated with an EIA RJ45 T568B standard plug (or structurally similar/comparable plug) with positions 1, 2, 3, 4, 5, 6, 7, 8 in use, i.e., occupied by a corresponding contact.
Thus, the bi-sectional/split lead frame design of the present disclosure provides a method for the utilization and automatic accommodation of two different types of plugs, one that is EIA RJ45 T568B and one that is an offset from EIA RJ45 T568B. As noted herein, the offset plug could include contacts 1, 2 and 7, 8 in present EIA RJ45 T568B configuration, but contacts 3, 6 and 4, 5 could be configured in the opposite or different ends as compared to the original slotted locations. If there are no contacts in EIA RJ45 T568B positions 3, 4, 5, 6, then lead frames 20, 22, 24, 26 are not mated and the capacitance composition balancer is automatically not implemented/energized. As such, the capacitive structures associated with the central pairs do not affect the system, which is highly desirable because the system would not require noise balancing therefrom (and any supplied noise balancing would from such capacitive structures would have a deleterious effect on system performance).
The pads/plates 114, 116 are a limited distance from the point of plug mating contact, thereby reducing the NEXT noises that is created from the plug interaction for plug assemblies that contact the central lead frame pairs (so as to energize capacitive pads/plates 114, 116 and 113, 115). An average distance of about 0.213 inches is generally utilized to counterbalance the injected noise, since this is an electrically short distance that produces near instantaneous feedback of balancing noise vectors. The pads 113, 115 are generally configured, dimensioned and deployed so as to produce an estimated 1 pF of capacitance reactance. This parameter is effected, at least in part, by the dielectric material (if any) and the spacing of the pads.
At the opposite ends of the lead frames, i.e., at the far end of rear end portions 12b, 26b, the lead frames 22, 26 generally engage a printed circuit board (PCB) that generates further capacitance to compensate for noise associated with the plug/jack interaction. In addition, an inductance reactance is effected between lead frames 22, 26 in the adjacent regions 118 and 120, respectively. An average distance of about 0.190 inches may again be utilized to counter balance the undesirably injected noise, since this also is an electrically short distance that produces near instantaneous feedback of balancing noise vectors.
The interaction between the front end portion and the rear end portion of each central lead frame 20, 22, 24, 26 is substantially identical. For illustration purposes, the interaction between the front end portion 22a and rear end portion 22b of lead frame 22 will be described with reference to
The innermost contacts could also be contacts 20 and 26 with their respective pads being differential signal pair 3 of an EIA 568-B.2 RJ45 pin configuration. This configuration would aid in improving the impedance for differential signal pair 3, whose contacts are normally split, thereby reducing line capacitive reactance balance. Balance is re-inserted based on capacitance of the differential signal pair being the inner most combination. The contact arrangement could also be achieved with contacts 20, 24 with pads 113, 115 being the forward-most pad set, and the contacts 22, 26 with pads 114, 116. This arrangement of quad Xc accomplishes the same benefit, but provides another option for mechanical assembly.
As illustrated in
Both the front end portions and rear end portions of the bi-sectional lead frames are elongated beams that are supported in a cantilever fashion by the insert housing member. As a result, the forces exerted by the front and rear end portions of the two lead frames in the contact region constitute opposed forces, i.e., oppositely directed forces. The combined downward force of the front end portion and the upward force of the rear end portion of each bi-sectional lead frame is sufficient to provide reliable and stable contact resistance for signal transfer therebetween.
With further reference to
A dielectric material (not pictured) may be introduced between capacitive pads/plates 113, 115 to provide insulation from potential electrical short and/or control of capacitive reactance therebetween. The dielectric material may be configured and dimensioned to support the capacitive pads/plated 113, 115 in whole or in part. For example, a greater presence of dielectric material generally reduces capacitive coupling between capacitive pads/plates 113, 115.
With further reference to
Turning to
Also schematically illustrated are potential locations for capacitive interaction between respective lead frames, including the capacitive pads/plates and/or interdigitated members disclosed herein. Of note, when an insert/jack that includes bi-sectional lead frames of the present disclosure is engaged with a conventional RJ-45 plug, all eight (8) contacts would assume the “closed” state that is schematically depicted in
The formation of lead frames 16 through 30 results in optionally splitting the signal which reduces crosstalk noises, among other things, by causing separate and quad reactance; that is, one being the rear-end dual inductive/capacitive reactance section combination and the other being the dual static mode capacitive reactance at the free-end of the elongated contacts central pairs. The lead frames may be arranged and/or bent in different formats. One format aligns all contacts in order, which increases the parallelism of the wire pairs. Another exemplary format, in accordance with the present disclosure, aligns all contacts in two distinct bends with the lead frames associated with upper portion 12 in parallel to each other and the lead frames associated with the lower portion 14 in parallel to each other, but not parallel with regard to lead frames of differing associations, which reduces NEXT more effectively.
By enhancing and reducing the parallelism of the lead frames at opposing end portions to address known coupling problems inherent in the RJ45 plug system, lower capacitive and inductive coupling will occur as the frequency increases up to 500 MHz. The end result is an insert device that has lower NEXT, FEXT and impedance in certain wire pairs. The reduction of a majority of crosstalk noise occurs by combining indirect and direct signal coupling in the lead frames associated with central pairs 1 and 3, as well as the other pairs 2 and 4 in the RJ45 plug.
Negative noise that was introduced is optionally counter coupled with a balance quad (4-section) positive noise, therefore reducing the total noise effects and re-balancing the wire pairs output. Each balance coupling section is located in separated isolated zones. By placement of such sections in isolated zones, the interaction of electro magnetic interference (EMI) between sections is greatly reduced. Such functionality may also be effective to reduce coupling variations.
The lead frames are generally electrically short, approximately less than 0.27 inches in length, which reduces the negative noise coupling by reducing the parallelism of the adjacent victim wire and reducing the signal delay to a PCB that could contain further coupling circuitry. The additive positive noise and reduction of the unwanted negative noise coupling of the lead frames works at substantially the same moment in time, which allows optimal reduction for lower capacitive and inductive coupling. The combination of the split signals provides, inter alia, an enhanced low noise dielectric modular housing for high speed telecommunication connecting hardware systems. The end result is a modular insert device that has lower NEXT, FEXT and impedance within its wire pairs.
With reference to
With initial reference to
PCB 240 includes capacitive traces that function to introduce compensation to the lead frames when combined with a plug (not pictured). PCB 240 includes interdigitated capacitive traces that function to generate compensation for re-balancing the signals carried by the disclosed bi-sectional lead frames. To the extent a conventional RJ-45 plug is combined with subassembly 200, e.g., by connection to a jack containing subassembly 200, each of the bi-sectional lead frames deflects into a “closed” state. In other words, the front end portions 216a, 218a, 220a, 222a, 224a, 226a, 228a, 230a deflect into electrical contact with the rear end portions 216b, 218b, 220b, 222b, 224b, 226b, 228b, 230b. In the “closed” state, the capacitive functionality associated with PCB 240 generates compensation for purposes of offsetting noise generated in connection with the plug/jack assemblage.
In instances where a plug is introduced having an alternative contact layout, e.g., a plug that is compliant with the IEC 60603-7-7 standard, not all lead frames will be deflected to a “closed” state. Rather, certain lead frames may remain in the “open” state, thereby isolating the capacitive functionality associated with PCB 240 from generating compensation with respect to such lead frames. A completed circuit with respect to such wire pairs is generally achieved through alternately located contacts within the jack and associated plug. Of note, the bi-sectional design of the lead frames prevents the potential for energizing PCB 240 with respect to the “open” state lead frames from the downstream circuitry that is communication with the applicable rear end portions, e.g., rear end portions 220b, 222b, 224b, 226b.
Turning to
PCB 340 includes capacitive traces that function to introduce compensation to the lead frames when combined with a plug (not pictured). PCB 340 includes capacitive pad-like or plate-like traces that function to generate compensation for re-balancing the signals carried by the disclosed bi-sectional lead frames. Thus, when a conventional RJ-45 plug is combined with subassembly 300, each of the bi-sectional lead frames deflects into a “closed” state, i.e., the front end portions 316a, 318a, 320a, 322a, 324a, 326a, 328a, 330a deflect into electrical contact with the rear end portions 316b, 318b, 320b, 322b, 324b, 326b, 328b, 330b. In the “closed” state, the capacitive functionality associated with PCB 340 generates compensation for purposes of offsetting noise generated in connection with the plug/jack assemblage.
As with the embodiment of
With reference to
Thus, the systems, apparatus and methods of the present disclosure provide advantageous designs that automatically accommodate plugs having differing contact layouts, such advantageous designs supplying desired levels of compensation without requiring new equipment and/or expensive rewiring. Thus, in exemplary embodiments, the victim crosstalk noise is reduced/eliminated by the combination of appropriately-placed positive feedback signal reactance circuitry. This operation is accomplished by forming appropriate contacts within the dielectric insert for achieving requisite noise reduction for the contact geometry involved, thereby increasing the system's signal-to-noise ratio and reducing the system's bit error rate.
Signal noise is re-balanced by a requisite amount, based on the design/layout of the mating plug. For conventional RJ-45 contact layouts, front-end capacitive functionality is energized through deflection of the central bi-sectional lead frames, thereby transforming such lead frames from an “open” state to a “closed” state. Insert devices/jacks fabricated according to the present disclosure may be effective to reduce the differential noise input voltage ratio signal by at least fifty percent. This reduction and controlled Xc also aid in reducing the cabling Power Sum Alien Crosstalk (PSANEXT). By reducing the NEXT noise, the disclosed systems/methods also reduce the amount of coupling energy that has the potential to radiate upon an adjacent line. PSANEXT (as described in the EIA 568-B.2-10 document) is a new noise parameter that has a limited margin requirement for proper 10GBASE-T signal transmission over copper cabling.
Although the systems, apparatus and methods have been described with respect to exemplary embodiments herein, it is apparent that modifications, variations, changes and/or enhancements may be made thereto without departing from the spirit or scope of the invention as defined by the appended claims. Accordingly, the present disclosure expressly encompasses all such modifications, variations, changes and/or enhancements.
This application is a divisional of co-pending U.S. Non-Provisional application Ser. No. 11/818,478, entitled “MODULAR INSERT AND JACK INCLUDING BI-SECTIONAL LEAD FRAMES”, filed Jun. 14, 2007.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 11818478 | Jun 2007 | US |
| Child | 12351350 | US |
