Receptacle with crosstalk optimizing contact array

[0001] The invention relates generally to electrical connectors, in particular to a modular plug or plug with crosstalk limiting system.

[0002] Various electrical installations, such as those that are used to transmit signals in the telecommunications industry, include sets of connectors with electric wires arranged in differential pairs. One conductor in the differential pair conducts a positive signal and the other conductor conducts a negative signal, which is to have the same absolute amplitude, but the opposite polarity.

[0003] An RJ-45 electrical connector having a plug and socket is one example of a connector used to conduct electrical signals in differential pairs. The RJ-45 plug has four differential wire pairs. The plug has a high noise level due to the wiring arrangement defined by industry standards.

[0004] Many differential pairs are arranged in the connector in close proximity to each other and generate unwanted coupling of the electromagnetic signal or crosstalk, which impairs the quality of the signal transmission. Another problem encountered is impedance mismatch when the signal is transmitted through the plug and socket assembly. The mismatched impedance causes some of the electrical signal to be reflected back to its source. The amount of reflection that occurs as a result of impedance mismatch can be quantified as a loss of return.

[0005] Furthermore, connector assemblies are used to transfer data at higher frequencies and wider bandwidths. The problem is that as the frequency increases, there is a greater signal deterioration in the system due to EM coupling, return loss and impedance mismatch.

[0006] The present invention is directed to a socket assembly, generally of the type disclosed in US-B16,558,207 and again cited in the not-known part of claim 1, including a housing having a front and rear end, where the front end is configured to insert the plug, the rear end is configured to receive the wires terminating the wires; a circuit board including a plurality of contact openings, the circuit board being held in a housing; and a plurality of system contacts arranged in a contact arrangement within the housing, each of the plurality of system contacts comprising a main portion and a contact terminal, wherein the main portion of each of the many system contacts extends generally perpendicular to the circuit board, with the contact terminal of each contact pin the system has a first bend forming the first terminal component running parallel to the circuit board and a second bend forming the second terminal component of each of the many contacts of the system, perpendicular to the circuit board, where the second terminal component of each of the multiple circuit contacts is received through one of the multiple contact holes in the circuit board, and where the multiple circuit contacts also include a first and second subset of circuit contacts whose first terminal component extends in the same direction from the first bends at the first and second distances, respectively, which are different from each other.

[0007] The latter US-B1 is considered because of the increasing degree of elasticity of the contacts in the contact arrangement of the modular socket type connector, and not the problem of reducing crosstalk. The contact arrangement comprises the first terminal components, all of which extend in the same direction, and the ends of the solder pins of the wires that form the second components of the terminals of the terminal arrangement are arranged in two rows.

[0008] US-B1 -6,464,541 discloses a socket assembly in which the contact wires are bent so that their base ends or second terminal parts are arranged in three rows, running perpendicular to the circuit board. This determines the position of the holes on the circuit board in which the base ends are mounted. It is believed that this configuration compensates for crosstalk.

[0009] US-B1-5,626,497 refers to a modular type connector socket in which the intermediate parts of the contacts in the contact system are formed with overlapping fragments defining capacitors designed to limit crosstalk. The end portions of the system contacts include first components that run in opposite directions, and end or second components that are arranged in two rows.

[0010] US-B 1-6,190,211 discloses an insulation displacement connector comprising a base circuit board having two transverse rows of metal contact holes and two longitudinal rows of metal contact holes. The contact holes in the rows are interconnected by multiple conductors in a configuration that is designed to limit crosstalk.

[0011] It is an object of the invention to provide a construction of a socket assembly capable of canceling crosstalk and reducing return losses to improve electrical performance.

[0012] According to the present invention, there is provided a socket assembly as defined in claim 1. 1.

[0013] The invention will now be described by way of example with reference to the accompanying drawings, in which:

Fig. 1 is a perspective view of an output type socket assembly according to an embodiment of the present invention, Fig. 2 is a socket assembly of Fig. 1 with the housing removed, according to an embodiment of the present invention, Fig. 3 is a front perspective view of a subassembly within the socket assembly of Fig. 1, according to an embodiment of the present invention, Fig. 4 shows the front part of the circuit board of Fig. 2, according to an embodiment of the present invention, Fig. 5 is a rear perspective view of the contact system formed according to an embodiment of the present invention, Fig. 6 is a side view of the contact arrangement of Fig. 5 formed according to an embodiment of the present invention, Fig. 7 is a rear perspective view of the subassembly of Fig. 2 according to an embodiment of the present invention of the invention, and Fig. 8 shows a contact input pattern according to an embodiment of the present invention.

[0014] The preceding summary, as well as the following detailed description of some embodiments of the present invention, will be better understood upon reading with reference to the attached drawing figures. It should be understood that the present invention is not limited to the arrangements and instrumentation shown in the accompanying drawings.

[0015] Fig. 1 shows a socket assembly 100. The socket assembly 100 has a front end 102 and a rear end 114. -2. The housing 108 partially includes a contact arrangement 106 within the cavity 110. In the example of Fig. 1, the cavity 110 adopts the RJ-45 plug. (not shown) inserted through the front end 102. The RJ-45 plug has contacts that electrically engage with the contact system 106. The circuit board 148 (Fig. 2) is mounted in the housing 108 closest to the rear end of the housing 104. Front end 116 of wire connector housing 112 cooperates with the rear end of housing 104. Wire connector housing 112 receives wire wires from the cable (not shown) through the rear end 114, which electrically couples with the terminating contacts 113 held in the wire connector housing 112. [0016] Fig. 2 shows the socket assembly 100 of Fig. 1 with the housing 108 removed. The wire termination contacts 113 are received through the wire termination holes (shown in Figures 3 and 4) in the circuit board 148 and establish contact with the conductive material on the circuit board 148.

[0017] In this example, the wires terminating contacts 113 are insulation displacement contacts (IDC), but other connecting means may be used. Wires within the cable terminate at the IDC end of the IDC contacts. The opposite end of the IDC contacts engages the circuit board 148 within the wire terminating contact openings. The wire terminating contacts 113 terminate on the circuit board 148 with needle eye contacts, compatible contact pins, solder, push connection, or other means known to those skilled in the art.

[0018] Fig. 3 is a front perspective view of the subassembly 120 within the seating assembly 100 of Fig. 1. The subassembly 120 includes a base 122 which may be formed of plastic or other non-conductive material. The base 122 has a leading edge 103 located in the vicinity of the front end 102 and directed towards it (Fig. 1) of the housing 108, and a rear edge 105 located in the vicinity of the rear end of the housing 104 and facing it. Optionally, the base 122 may have a printed circuit board surface on which the contact system 106 may lie. Alternatively, the circuit board (not shown) may be used instead of the base 122 to provide signal processing. [0019] The rear edge 105 includes posts 107 that are configured to enter into the openings 109 in the front portion 150 of the circuit board 148. The posts 107 may perform alignment and / or locking functions to position and hold the rear edge 105 relative to the front portion 150 of the circuit board 148 in the desired orientation and orientation. The base 122 includes a series of parallel notches 123 formed therein that extend to the leading edge 103 and are spaced apart in a desired manner. The base 122 also includes a bridge 125 closest to the rear edge 105. The bridge 125 has a series of posts 127 extending upward from it and separated from each other by slots 129 aligned with the notches 123. The system contacts in the contact arrangement 106 have an interference fit with the posts 127 and slots 129.

The contact arrangement 106 includes contacts 124, 126, 128, 130, 132, 134, 136 and 138 which are arranged parallel to each other and arranged in a direction such that they extend from the parallel notches 123 closest to the leading edge 103 to the rear edge 105 base 122. In the contact arrangement 106, eight contacts are shown; however, more or fewer contacts can be used. System contacts 124 and 126 form the first differential pair 140, system contacts 128 and 134 form the second differential pair 142, system contacts 130 and 132 form the third differential pair 144, and system contacts 136 and 138 form the fourth differential pair 146. System contacts 124 and 126 , 130 and 132 and 136 and 138 of the first, third and fourth differential pair 140, 144 and 146, respectively, are arranged in their immediate vicinity. However, the contacts 128 and 134 of the second differential pair 142 are not arranged in their immediate vicinity. Instead, the contacts 128 and 134 of the second differential pair 142 are separated or separated from each other by the introduced third differential pair 144. System contact 128 is adjacent to system contacts 126 and 130 of the first and third differential pair 140 and 144, respectively, while system contact 134 is adjacent to contacts 132 and 136 of the third and fourth differential pair 144 and 146, respectively. System contacts 124, 126, 128 , 130, 132, 134, 136 and 138 extend along base 122 in a coplanar arrangement and have contact terminals 216 (Figure 5) that enter the circuit board 148, defining the input pattern of contacts 153 (Figure 4). Contact terminals 216 can be soldered to holes in circuit board 148 or connected to the holes using a compatible contact pins design or other interconnection known in the art.

[0021] It should be understood that the circuit board 148, base 122 and socket assembly 100 may vary in size, depending on the specifications given by the customer. For example, it may be desirable to make the socket assembly 100 as small or compact as possible. In addition, further improvements can be added to circuit board 148 to modify transmitted signals.

[0022] Fig. 4 shows the front portion 150 of the circuit board 148 of Fig. 2. The circuit board 148 has an upper end 160 and a lower end 162. Contact holes 188, 190, 192, 194, 196, 198, 200 and 202 form an input pattern contacts 153, which is associated with a particular layout arrangement. The input pattern of contacts 153 is shown in the central part 164 of the circuit board 148, but can also be located in a non-central position, such as, for example, by moving the input pattern of contacts 153 up, down, right or left. Contact holes 188, 190, 192, 194, 196, 198, 200 and 202 receive contact terminals 216 of the system contacts, 124, 126, 128, 130, 132, 134, 136 and 138, respectively. Wire termination contact holes 170, 172, 174, 176, 178, 180, 182 and 184 form a wire terminating contact pattern 154 located in the upper and lower parts 166 and 168 of circuit board 148, for receiving wire terminating contacts 113.

[0023] The contact arrangement 106 enters the circuit board 148 in the input contact pattern 153 to optimize signal integrity, such as by minimizing crosstalk interference, while providing the configuration of the contact arrangement 106. As shown in Figure 3, contacts 124 and 126 and contacts 136 and 138 cross over each other. Therefore, system contact 126 enters circuit board 148 closest to outer edge 186, and system contact 136 enters circuit board 148 closest to outer edge 187.

[0024] Paths (not shown) electrically connect each of the contact holes 188, 190, 192, 194, 196, 198, 200 and 202 within central portion 164, with the corresponding one contact hole of wire end 170, 172, 174, 176, 178, 180, 182 and 184 in both the top and bottom of 166 or 168. Each of the holes was given a number (corresponding to a contact or contact pin) within Figure 4 to provide one example of an interconnection pattern. Contact hole 188 is electrically connected to the wire end contact hole 178, while contact hole 190 is electrically connected to the wire end contact hole 180. Contact openings 192, 194, 196, 198, 200 and 202 are electrically connected to the wire end contact openings 170, 174, 176, 172, 182 and 184, respectively. Other interconnection patterns may be used.

[0025] Fig. 5 is a view of the contact system 106 according to an embodiment of the present invention. Similar item numbers have been used. The first, second and third parts 210, 212 and 214 together form the main part 218, which is held generally perpendicular to the circuit board 148. In the first part 210, system contacts 124, 126, 128, 130, 132, 134, 136 and 138 extend flat against base 122 (Fig. 3) and perpendicular to circuit board 148. In the second part 212, system contact pairs 124 and 126, 130 and 132, and 136 and 138 intersect each other, while system contacts 128 and 134 are still flat relative to base 122. The intersecting pattern compensates for part of the crosstalk generated in the plug.

In the third portion 214, the contacts of array 124, 126, 128, 130, 132, 134, 136 and 138 extend flat relative to the base 122.

[0026] Each of the system contacts 124, 126, 128, 130, 132, 134, 136 and 138 has a contact tip 216. Each contact tip 216 is bent to form the first arc 224 at an angle of about 90 degrees while the contacts of the system 124, 128, 132 and 136 are bent upwards as shown by arrow A, and system contacts 126, 130, 134 and 138 are bent downwards as indicated by arrow B. The first component end portion 228 extends up or down parallel to the circuit board 148 at one or two distances, and then a second arc 226 is formed at an angle of about 90 degrees. The second component end portion 222 runs perpendicular to circuit board 148 and through one of the contact holes 188, 190, 192, 194, 196, 198, 200 and 202 in circuit board 148, forming the input pattern of contacts 153 (Fig. 4), which is further discussed below.

[0027] Fig. 6 is a side view of the contact system 106 according to an embodiment of the present invention. First, second and third parts 210, 212 and 214 and contact tips 216 are shown using similar position numbers. Plane 220 represents a plane substantially parallel to the plane of the main portion 218 that is perpendicular to the circuit board 148. The second component end portions 222 run in four parallel rows formed at distances D1, D2_t D3 and D4 from plane 220. Distances D1 and D4 are greater than distances D2 and D3. In addition, the distances D1 and D4 are equal and the distances D2 and D3 are equal.

[0028] Fig. 7 is a rear perspective view of the subassembly 120 of Fig. 3 to better show the input contact pattern 153 of the second component end pieces 222. The rear face part 152 of the circuit board 148 is shown. The second component end pieces 222 enter the contact holes 188 , 190, 192, 194, 196, 198, 200 and 202 in the front portion 150 and may extend through and beyond the rear front portion 152 of circuit board 148. The second component end portions 222 may be soldered to the circuit board 148 or may be made as a compatible contact pin, needle eye, or other type connection as known in the art. [0029] The spacing of contact openings 188, 190, 192, 194, 196, 198, 200 and 202 relative to each other and the spacing of the contact openings of wire ends 170, 172, 174, 176, 178, 180,182 and 184 with respect to each other is determined so to achieve the desired electrical characteristics. For example, contact holes 188, 190, 192, 194, 196, 198, 200 and 202 and contact holes for wire ends 170, 172, 174, 176, 178, 180, 182 and 184 can form patterns for engaging and isolating certain contacts.

[0030] The contact pattern of the wire ends 154 will be discussed in a first order, while the input pattern of the contacts 153 will be further discussed below. In the cable connected to the terminals of the wire terminals 113 of the wire connector housing 112, two wires from each pair of wires are twisted together. In the RJ-45 application, the wires are paired as pairs of 1/2, 3/6, 4/5 and 7/8 wires that are associated with the first, second, third and fourth pair 140, 142, 144 and 146, respectively. Each pair of wires is received through the contact holes of the wire ends that are closest to the various corners of plate 148. In particular, a pair of 1/2 wires is received through the contact holes of the wire ends 178 and 180 closest to the first corner, a pair of 3/6 wires is received through the contact holes of the wire ends 170 and 172 closest to the second corner, a pair of wires 7/8 is received through the contact openings of the ends of wires 182 and 184 closest to the third corner, and the pair of 4/5 wires is received through the contact holes of the wire ends 174 and 176 nearest the fourth corner.

[0031] The contact openings of the wire ends 170, 172, 174, 176, 178, 180, 182 and 184 are partially arranged so as to avoid additional interference in the socket assembly 100. As dictated by the industry standard, significant interference occurs in the plug, whereby most interference occurs between differential pairs 142 and 144. Because this pairing connection has the greatest interference, the contact pattern of wire terminator 154 isolates 3/6 and 4/5 wire pairs from each other. Referring to Fig. 4, the contact openings of the wire ends 170 and 172 receive the wire end contacts 113 interconnected with a pair of 3/6 wires, and the contact openings of the wire ends 174 and 176 receive the contacts of the wire ends 113 interconnected with a pair of wires 4/5 . The contact holes of the wire ends 170 and 172 are located in one corner of the upper portion 166, while the contact holes of the wire ends 174 and 176 are located in the opposite corner, respectively, in the bottom portion 168, isolating the second and third differential pair from each other. In other words, the second and third differential pairs are spaced far apart on circuit board 148.

[0032] The contact pattern of the wire ends 154 also takes into account the ease of connecting the cab to the socket assembly 100. The two color schemes defined by the industry standards for RJ-45 are called 568A and 568B, and match the pin numbers with the colors of the cable wires. Two sets of pairs of wires are typically marked with special colors and therefore, within the cable, the pair of 4/5 wires is blue and the pair of 7/8 wires is brown. For pattern 568A, the 1/2 wire pair is green and the 3/6 wire pair is orange. Alternatively, for pattern 568B, the 1/2 wire pair is orange and the 3/6 wire pair is green. Another issue relates to the directional arrangement of the wires within the kabia shell. Although not required by industry, the common wire color combination is blue-orange-green-brown, which rotates either clockwise (CW) or counterclockwise (CCW) clockwise, depending on which end the cable is being watched. Therefore, there are four main patterns that can be represented: pattern A and CCW, pattern A and CW, pattern B and CCW, and pattern B and CW. The contact pattern of the wire end 154 has been chosen so that one of these four main patterns fits exactly into the socket, without having to change or cross wire pairs as part of the natural directional cable layout, resulting in easy installation where possible. The pattern selected for this embodiment was pattern B and CCW (counterclockwise rotation).

[0033] Responding to industrial principles, the terminal pattern of the wire terminations 154 further improves the characteristics by separating interfering pairs. The pair of 4/5 wires is blue and corresponds to the contact openings of the wire ends 174 and 176, and the pair of 3/6 wires correspond to the contact openings of the wire ends 170 and 172, which are located in the opposite corner of the plate 148 relative to the contact holes of the ends wires 174 and 176. The 3/6 wire pair can be green or orange. Therefore, in one embodiment, the 1/2 wire pair is orange and corresponds to the contact holes of the wire ends 178 and 180, while the 3/6 wire pair is green and corresponds to the contact holes of the wire ends 170 and 172. In another example versions, a pair of 1/2 wires may be green, while a pair of 3/6 wires may be orange.

[0034] The input pattern of contacts 153 will now be discussed. As stated previously, in the RJ-45 plug one of the four differential pairs is split around the other. Industrial standards require split pair, and also dictate how much interference there should be in the plug. The highest degree of crosstalk is created between these two pairs, but other pair connections also show crosstalk, which is not insignificant. The reason is the partly large parallel blades in the plug, and sometimes the parallel nature of the wires in which they are arranged in the plug. Therefore, it is desirable to counteract these disturbances in the socket assembly 100, such as by compensating in the socket assembly 100, so that the cooperating connector (plug and socket assembly 100 connected together) have much less interference than the plug itself.

[0035] FIG. 8 shows the groupings and relationships between contact holes 188, 190, 192, 194, 196, 198, 200 and 202 within the contact pattern of contact 153. Each of contact holes 188, 190, 192, 194, 196, 198, 200 and 202 has measure 262. Circles and lines are used to show relationships and / or distances between centers 262 of contact holes 188, 190, 192, 194, 196, 198, 200 and 202, and therefore the wheels and lines themselves are not part of the contact input pattern 153 .

[0036] The first group 230 includes contact holes 188, 192 and 196 arranged in a triangular pattern. The 232 wheel, which may have a minimum diameter of 1.02 mm (0.04 inches), captures the center 262 of each of the contact holes 188, 192 and 196. In one embodiment, the 232 wheel may have a diameter of 2.08 mm (0.082 inches) Optionally, the 232 wheel can have a diameter of up to 3.56 mm (0.140 inch). The second group 234 includes contact holes 194, 198 and 202, which are also arranged in a triangular arrangement. Wheel 236 captures the center 262 of each of the contact holes 194, 198 and 202, and may also have a diameter of 1.02 mm to 3.56 mm (0.04 inches to 0.140 inches).

[0037] The input pattern of contacts 153 can be further described by referring to Fig. 6 again. The plane 220 is indicated in Fig. 8. The first subset 254 includes contact holes 200, 196 and 188, and the center 262 of each is a distance D1 from the plane 220. The second subset 256 includes a contact hole 192 whose center 262 is a distance D2 from the plane 220. The third subset 258 includes a contact hole 198 whose center 262 is the distance D3 from the plane 220. The fourth subset 260 includes contact holes 202, 194 and 190, and the center 262 of each is a distance D4 from the plane 220. As previously stated, the distances D1 and D4 are equal and the distances D2 and D3 are equal.

[0038] As discussed previously, eight parallel blades in the plug experience crosstalk. As for the second differential pair (3/6 blades) and the third differential pair (4/5 blades), blades 3 and 4, and blades 5 and 6 have the highest level of interference due to their close proximity to each other, respectively in the assembly sockets 100, system contacts 128 and 130, and system contacts 132 and 134 experience high levels of interference due to their close proximity to each other. It is desirable to isolate sets of contacts experiencing high levels of interference. Thus, system contacts 128 and 130 are received by contact openings 192 and 194 respectively, which are spaced apart, and system contacts 132 and 134 are received by contact openings 196 and 198 respectively, which are spaced apart. In fig. 8 line 246 runs between centers 262 of contact openings 192 and 194, and line 248 extends between centers of 262 contact openings 196 and 198, representing the distance between centers of 262 contact openings that may be from 3.05 mm to 5.08 mm (0.120 to 0.20 inches). In one embodiment, the distance may be 4.06 mm (0.160 inches).

[0039] Interference in the socket assembly 100 can be further counteracted by compensation by placing other system contacts close together. System contacts 128 and 132 are received respectively through contact holes 192 and 196, which are closely spaced, and system contacts 130 and 134 are received via contact holes 194 and 198, respectively, which are closely spaced. In fig. 8 line 238 runs between centers 262 of contact openings 192 and 196, and line 240 extends between centers of 262 contact openings 194 and 198, representing the distance between the centers of the respective contact openings 262, which can be from 0.51 mm to 2.54 mm (0 , 02 inches to 0.100 inches). In one embodiment, the distance can be 1.63 mm (0.064 inches).

[0040] Three of the differential pairs experience a secondary level of interference, or a second order crosstalk on the plug. The second differential pair (3/6 blades) experiences high levels of interference with both the first differential pair (1/2 blades) and the fourth differential pair (7/8 blades) due to their proximity to the plug and because the second differential pair is a shared pair.

[0041] To separate signals experiencing high levels of interference, system contacts 126 and 128 are received by contact holes 190 and 192 respectively, which are located away from each other, and system contacts 134 and 136 are received by contact holes 198 1200 respectively, which are far apart. In fig. 8 line 250 runs between centers 262 of contact holes 190 and 192, and line 252 extends between centers of 262 contact holes 198 and 200, showing the distance between centers of 262 contact holes that may be between 3.05 mm and 5.08 mm (0.120 to 0.20 inches). Similarly, to couple signals to counteract crosstalk on the RJ-45 plug, contact holes 188 and 192 receive system contacts 124 and 128, respectively, and contact holes 198 and 202 receive system contacts 134 and 138, respectively, are placed closer together on the board circuits 148. In fig. 8 line 242 runs between centers 262 of contact openings 188 and 192, and line 244 extends between centers of 262 contact openings 198 and 202, representing the distance between centers 262 of respective contact openings, which may be from 0.51 mm to 2.54 mm (0 , 02 inches to 0.100 inches).

[0042] The return loss that occurs on the plug and socket assembly 100 is also included. The signal sent to the contact pins (or contacts or wires) in a differential pair has an impedance based on at least one of the conductor cross-sections, the distance between conductors and the dielectric constant separating these two conductors in pair. The adjacent contacts of the first, third and fourth differential pair 140, 144 and 146 have essentially the same geometry and are close to each other in the socket assembly 100, which causes the impedance between the contacts of each pair to be lower than desired. By increasing the impedance to match the target impedance, such as 100 ohms, the return loss is reduced. Therefore, contact holes 200 and 202, receiving the contacts of the fourth differential pair 136 and 138, respectively, are spaced apart than contact holes 188 and 190 receiving the contacts of the first differential pair 124 and 126, and the contact holes 194 and 196 respectively receiving the contacts respectively systems 130 and 132 of the third differential pair. The distance between the contact holes of the differential pair can be increased to increase impedance, ensuring a more favorable return loss.

[0043] Although the invention has been described in terms of various, specific embodiments, those skilled in the art will recognize that the invention may be implemented with modifications falling within the scope of the claims.