Methods and Apparatus for Reducing Crosstalk in Electrical Connectors

• US 20080020652A1
• Filed: 08/03/2007
• Published: 01/24/2008
• Est. Priority Date: 03/12/2004
• Status: Active Grant

• Current Assignee: Panduit Corporation
• Original Assignee: Panduit Corporation
• Inventors: Caveney, Jack, Bolouri-Saransar, Masud, Lesniak, Scott
• Granted Patent: US 7,823,281 B2
• Time in Patent Office: Days
• US Class Current: 439/676
• CPC Class Codes: H01R 12/592 connections to contact elements
• CPC Class Codes: H01R 12/62 connecting to rigid printed circuits or like structures
• CPC Class Codes: H01R 12/675 with contacts having at least a slotted plate for penetration of cable insulation, e.g. insulation displacement contacts for round conductor flat cables
• CPC Class Codes: H01R 12/775 Ground or shield arrangements
• CPC Class Codes: H01R 13/46 Bases; Cases
• CPC Class Codes: H01R 13/502 composed of different pieces H01R13/514 takes precedence
• CPC Class Codes: H01R 13/6461 Means for preventing cross-talk
• CPC Class Codes: H01R 13/6466 on substrates, e.g. printed circuit boards [PCB]
• CPC Class Codes: H01R 13/6467 by cross-over of signal conductors
• CPC Class Codes: H01R 13/6658 on printed circuit board H01R13/6666 - H01R13/6691 take precedence
• CPC Class Codes: H01R 13/719 specially adapted for high frequency, e.g. with filters
• CPC Class Codes: H01R 2107/00 Four or more poles
• CPC Class Codes: H01R 2201/04 for network, e.g. LAN connectors
• CPC Class Codes: H01R 24/62 Sliding engagements with one side only, e.g. modular jack coupling devices
• CPC Class Codes: H01R 24/64 for high frequency, e.g. RJ 45
• CPC Class Codes: H01R 4/2429 mounted in an insulating base
• CPC Class Codes: H01R 4/2433 one part of the base being movable to push the cable into the slot
• CPC Class Codes: H05K 1/0228 Compensation of cross-talk by a mutually correlated lay-out of printed circuit traces, e.g. for compensation of cross-talk in mounted connectors balanced signal pairs H05K1/0245
• CPC Class Codes: H05K 1/028 Bending or folding regions of flexible printed circuits H05K1/0283 takes precedence
• CPC Class Codes: H05K 1/189 characterised by the use of a flexible or folded printed circuit H05K3/326 takes precedence
• CPC Class Codes: H05K 2201/09245 : Crossing layout alternating conductors H05K2201/097
• CPC Class Codes: H05K 2201/10189 : Non-printed connector
• CPC Class Codes: Y10S 439/941 : Crosstalk suppression
• CPC Class Codes: Y10T 29/49121 : Beam lead frame or beam lead device
• CPC Class Codes: Y10T 29/49128 : Assembling formed circuit to base
• CPC Class Codes: Y10T 29/49147 : Assembling terminal to base
• CPC Class Codes: Y10T 29/49174 : Assembling terminal to elongated conductor
• CPC Class Codes: Y10T 29/49222 : forming array of contacts or terminals

Abstract

An apparatus and method for crosstalk compensation in a jack of a modular communications connector includes a flexible printed circuit board connected to jack contacts and to connections to a network cable. The flexible printed circuit board includes conductive traces arranged as one or more couplings to provide crosstalk compensation.

Claims

1. A method of compensating for crosstalk in a modular communication connector comprising a plug and a jack, the jack comprising a plurality of jack contacts and a plurality of insulation displacement connectors (IDCs) configured to connect to wires of a cable, each jack contact having an interface at which the plug, when inserted into the jack, contacts the jack contact, the method comprising:

connecting a flexible printed circuit (FPC) to the jack contacts such that a first end of the FPC is connected to each jack contact approximately adjacent to and on an opposite side from the interface; and

connecting a second end of the FPC to the IDCs, the FPC providing a network path for at least two conductor pairs between the jack contacts and the IDCs.

2. The method of claim 1, further comprising attaching the second end of the FPC to a rigid printed circuit board.

3. The method of claim 1, wherein:

the network path comprises conductive traces that provide crosstalk compensation and include a Near End (NEXT) compensation zone, a Near End (NEXT) crosstalk zone, a first transition zone between the jack contacts and the NEXT crosstalk zone, and a second transition zone between the NEXT compensation zone and the NEXT crosstalk zone, and

at a first frequency the NEXT crosstalk zone has an associated magnitude of total crosstalk coupling that is approximately equal to that of a specification plug and the NEXT compensation zone has an associated magnitude of total compensation coupling that is slightly less than twice that of a specification plug plus that of the first and second the transition zones.

4. The method of claim 3, wherein the NEXT compensation zone, the NEXT crosstalk zone, and the first and second transition zones each have distributed couplings and substantially no remote couplings.

5. The method of claim 4, wherein at a first frequency, a first phase angle change between an effective center of couplings of an installed specification plug and a center of the NEXT compensation zone is approximately equal to a second phase angle change between a center of the NEXT crosstalk zone and a center of the NEXT compensation zone.

6. The method of claim 5, wherein the resultant Forward NEXT is substantially equal to Reverse NEXT.

7. The method of claim 4, wherein the NEXT compensation zone comprises a remote compensation coupling that has a magnitude that decreases as the frequency increases.

8. The method of claim 1, wherein:

the network path comprises conductive traces that provide crosstalk compensation and include a Near End (NEXT) compensation zone, a Near End (NEXT) crosstalk zone, a first transition zone between the jack contacts and the NEXT crosstalk zone, and a second transition zone between the NEXT compensation zone and the NEXT crosstalk zone, and

total inductive coupling of the NEXT compensation zone is approximately equal to total inductive coupling of a specification plug and the jack minus the NEXT compensation zone.

9. The method of claim 1, wherein:

the network path comprises conductive traces that provide crosstalk compensation and include a Near End (NEXT) compensation zone, a Near End (NEXT) crosstalk zone, a first transition zone between the jack contacts and the NEXT crosstalk zone, and a second transition zone between the NEXT compensation zone and the NEXT crosstalk zone, and

the NEXT compensation zone is approximately equal in length to the NEXT crosstalk zone.

10. A method of compensating for crosstalk in a modular communication connector comprising a plug and a jack, the jack comprising a plurality of jack contacts and a plurality of insulation displacement connectors (IDCs) configured to connect to wires of a cable, each jack contact having an interface at which the plug, when inserted into the jack, contacts the jack contact, the method comprising:

connecting a circuit board to the jack contacts through flexible members such that a first end of the circuit board is connected through the flexible members to each jack contact approximately adjacent to and on an opposite side as the interface; and

connecting a second end of the circuit board to each of the IDCs,

the circuit board providing a network path for at least two conductor pairs between the jack contacts and the IDCs.

11. The method of claim 10, wherein the circuit board is a flexible printed circuit (FPC), the method further comprising attaching the second end of the FPC to a rigid printed circuit board.

12. The method of claim 10, wherein:

the network path comprises conductive traces that provide crosstalk compensation and include a Near End (NEXT) compensation zone, a Near End (NEXT) crosstalk zone, a first transition zone between the jack contacts and the NEXT crosstalk zone, and a second transition zone between the NEXT compensation zone and the NEXT crosstalk zone, and

at a first frequency the NEXT crosstalk zone has an associated magnitude of total crosstalk coupling that is approximately equal to that of a specification plug and the NEXT compensation zone has an associated magnitude of total compensation coupling that is slightly less than twice that of a specification plug plus that of the first and second the transition zones

13. The method of claim 12, wherein the NEXT compensation zone, the NEXT crosstalk zone, and the first and second transition zones each have distributed couplings and substantially no remote couplings.

14. The method of claim 13, wherein at a first frequency, a first phase angle change between an effective center of couplings of an installed specification plug and a center of the NEXT compensation zone is approximately equal to a second phase angle change between a center of the NEXT crosstalk zone and a center of the NEXT compensation zone.

15. The method of claim 14, wherein the resultant Forward NEXT is substantially equal to Reverse NEXT.

16. The method of claim 13, wherein the NEXT compensation zone comprises a remote compensation coupling that has a magnitude that decreases as the frequency increases.

17. The method of claim 10, wherein:

the network path comprises conductive traces that provide crosstalk compensation and include a Near End (NEXT) compensation zone, a Near End (NEXT) crosstalk zone, a first transition zone between the jack contacts and the NEXT crosstalk zone, and a second transition zone between the NEXT compensation zone and the NEXT crosstalk zone, and

total inductive coupling of the NEXT compensation zone is approximately equal to total inductive coupling of a specification plug and the jack minus the NEXT compensation zone.

18. The method of claim 10, wherein:

the network path comprises conductive traces that provide crosstalk compensation and include a Near End (NEXT) compensation zone, a Near End (NEXT) crosstalk zone, a first transition zone between the jack contacts and the NEXT crosstalk zone, and a second transition zone between the NEXT compensation zone and the NEXT crosstalk zone, and

the NEXT compensation zone is approximately equal in length to the NEXT crosstalk zone.

19. A method of compensating for crosstalk in a modular communication connector comprising a plug and a jack, the jack comprising a plurality of jack contacts and a plurality of insulation displacement connectors (IDCs) configured to connect to wires of a cable, each jack contact having an interface at which the plug, when inserted into the jack, contacts the jack contact, the method comprising:

connecting a flexible printed circuit (FPC) to the jack contacts approximately adjacent to and on an opposite side as the interfaces; and

connecting the FPC to each of the IDCs,

the FPC providing a network path for at least two conductor pairs between the jack contacts and the IDCs.

20. The method of claim 19, wherein connecting the FPC to the jack contacts comprises an end of the FPC directly contacting the jack contacts.

21. The method of claim 19, wherein connecting the FPC to the jack contacts comprises connecting the FPC to the jack contacts through flexible members.

22. The method of claim 19, wherein connecting the FPC to the jack contacts comprises pinching an end of the FPC between the jack contacts and a plurality of spring contacts, each spring contact extending from a first end of one of the jack contacts and curving in an “

S”

shape.

23. The method of claim 22 wherein the jack contacts comprise shorter jack contacts and longer jack contacts, the method further comprising:

disposing the jack contacts in a comb of a sled;

mounting second ends of the jack contacts in contact mounts of a mounting plate such that the second ends of the shorter jack contacts are disposed in the mounting plate in a direction of insertion of the plug from the second ends of the longer jack contacts disposed in the mounting plate; and

aligning the spring contacts with one another.

24. The method of claim 23 wherein the middle two jack contacts are the only two neighboring jack contacts that have the same length.

25. The method of claim 23 wherein the outermost jack contacts are longer jack contacts.