Methods and apparatus for reducing crosstalk in electrical connectors

• US 20050202697A1
• Filed: 03/11/2005
• Published: 09/15/2005
• Est. Priority Date: 03/12/2004
• Status: Active Grant

• Current Assignee: Panduit Corporation
• Original Assignee: Panduit Corporation
• Inventors: Lesniak, Scott M., Bolouri-Saransar, Masud, Caveney, Jack E.
• Granted Patent: US 7,252,554 B2
• Time in Patent Office: Days
• US Class Current: 439/77
• 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 crosstalk compensation apparatus for a modular communication connector comprising a jack and a plug, the jack having jack contacts consisting of metal cantilever beams, the apparatus comprising a flexible printed circuit mechanically and electrically connected at a first end to the jack contacts approximately opposite and adjacent to where the jack contacts interface with the plug as installed, the flexible printed circuit mechanically and electrically connected at a second end to network cable connectors, thereby providing a network path for at least two pairs between the jack contacts and the connectors.

2. The crosstalk compensation apparatus of claim 1, wherein the flexible printed circuit becomes or is attached at its second end to a rigid printed circuit board.

3. The crosstalk compensation apparatus 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 compensation zone, and a second transition zone between the NEXT compensation zone and the NEXT crosstalk zone.

4. The crosstalk compensation apparatus of claim 3, wherein 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.

5. The crosstalk compensation apparatus of claim 4, wherein at the first frequency the NEXT compensation zone has a 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.

6. The crosstalk compensation apparatus of claim 5, 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.

7. The crosstalk compensation apparatus of claim 6, 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.

8. The crosstalk compensation apparatus of claim 7, wherein the resultant Forward NEXT is substantially equal to Reverse NEXT.

9. The crosstalk compensation apparatus of claim 6, wherein the NEXT compensation zone comprises a remote compensation coupling that has a magnitude that decreases as the frequency increases.

10. The crosstalk compensation apparatus of claim 3, wherein 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.

11. The crosstalk compensation apparatus of claim 10, thereby resulting in relatively low Far End Crosstalk (FEXT).

12. The crosstalk compensation apparatus of claim 3, wherein the NEXT compensation zone is approximately equal in length to the NEXT crosstalk zone.

13. The crosstalk compensation apparatus of claim 1, wherein the jack contacts each have an associated length and width, the width being smaller than the length, and wherein the jack contacts do not conduct signal current down their length when the plug is installed in the jack.

14. The crosstalk compensation apparatus of claim 1, wherein at least two of the connectors have stems that are crossed.

15. The apparatus of claim 1, wherein the flexible printed circuit diverges from the jack contacts from where the flexible printed circuit is connected to the jack contacts.

16. A crosstalk compensation apparatus for a modular communication connector comprising a jack and a plug, the jack having jack contacts consisting of metal cantilever beams, the apparatus comprising a circuit board mechanically and electrically connected at a first end by flexible members to the jack contacts approximately opposite and adjacent to where the jack contacts interface with the plug as installed, the circuit board mechanically and electrically connected at a second end to network cable connectors, thereby providing a network path for at least two pairs between the jack contacts and the connectors.

17. The crosstalk compensation apparatus of claim 16, wherein the circuit board diverges from the jack contacts from where the flexible members are connected to the jack contacts.

18. The crosstalk compensation apparatus of claim 16, wherein the circuit board is a flexible printed circuit.

19. The crosstalk compensation apparatus of claim 18, wherein the flexible printed circuit becomes or is attached at its second end to a rigid printed circuit board.

20. The crosstalk compensation apparatus of claim 18, 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 compensation zone, and a second transition zone between the NEXT compensation zone and the NEXT crosstalk zone.

21. The crosstalk compensation apparatus of claim 20, wherein 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.

22. The crosstalk compensation apparatus of claim 21, wherein at the first frequency the NEXT compensation zone has a 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.

23. The crosstalk compensation apparatus of claim 22, 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.

24. The crosstalk compensation apparatus of claim 23, 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.

25. The crosstalk compensation apparatus of claim 24, wherein the resultant Forward NEXT is substantially equal to Reverse NEXT.

26. The crosstalk compensation apparatus of claim 20, wherein 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.

27. The crosstalk compensation apparatus of claim 26, thereby resulting in a relatively low Far End Crosstalk (FEXT).

28. The crosstalk compensation apparatus of claim 20, wherein the NEXT compensation zone is approximately equal in length to the NEXT crosstalk zone.

29. The crosstalk compensation apparatus of claim 18, wherein the jack contacts each have an associated length and width, the width being smaller than the length, and wherein the jack contacts do not conduct signal current down their length when the plug is installed in the jack.

30. The crosstalk compensation apparatus of claim 18, wherein at least two of the connectors have stems that are crossed.

31. A jack for use in a communication system, the jack cooperatively interfacing with a plug to connect a first communication cable to a second communication cable, each of the communication cables having a plurality of wires arranged in wire pairs, the jack comprising:

a plurality of insulation displacement contacts for connecting to the wires of the first communication cable;

a plurality of jack contacts for connecting to a plurality of plug contacts in the plug when the plug is inserted in the jack, the plug contacts being connected to the wires of the second communication cable; and

a circuit board connected at a first end to the plurality of insulation displacement contacts and flexibly connected at a second end to the plurality of jack contacts to form conduction paths from the wires of the first communication cable to the wires of the second communication cable, the circuit board including conductive traces arranged to provide crosstalk compensation.

32. The jack of claim 31, wherein the circuit board is a flexible printed circuit board having flexible members that attach to the jack contacts approximately opposite and adjacent to where the jack contacts interface with the plug contacts when the plug is installed.

33. The jack of claim 31, wherein flexible members attach the circuit board to the jack contacts approximately opposite and adjacent to where the jack contacts interface with the plug contacts when the plug is installed.

34. The jack of claim 33, wherein the circuit board is a flexible printed circuit board, wherein the first end is approximately normal to a plane defined by the jack contacts, and wherein the second end is rigidly supported for connection to the insulation displacement contacts.

35. The jack of claim 33, wherein the circuit board is a flexible printed circuit board that curves approximately 180 degrees from its first end to its second end, wherein the first end is approximately normal to a plane defined by the jack contacts, and wherein the second end is approximately normal to the insulation displacements contacts.

36. The jack of claim 33, wherein the insulation displacement contacts have stems that each include at least one 90 degree bend, wherein the circuit board is a flexible printed circuit board that curves approximately 90 degrees from its first end to its second end, wherein the first end is approximately normal to a plane defined by the jack contacts, and wherein the second end is approximately normal to the insulation displacements contacts.

37. The jack of claim 34, wherein the flexible printed circuit is attached to a rigid board near where the connectors are connected.

38. The jack of claim 31, wherein the conduction paths comprise 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.

39. The jack of claim 38, wherein 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.

40. The jack of claim 39, wherein at the first frequency the NEXT compensation zone has a 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.

41. The jack of claim 38, 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.

42. The jack of claim 38, 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, thereby resulting in Forward NEXT being substantially equal to Reverse NEXT.

43. The jack of claim 42, wherein total inductive coupling of the NEXT compensation zone is approximately equal to total inductive coupling of the specification plug and the jack minus the NEXT compensation zone, thereby resulting in reduced Far End Crosstalk (FEXT).

44. The jack of claim 38, wherein the NEXT compensation zone is approximately equal in length to the NEXT crosstalk zone.

45. The jack of claim 31, wherein the jack contacts each have an associated length and width, the width being smaller than the length, and wherein the jack contacts do not conduct signal current down their length when the plug is installed in the jack.

46. The jack of claim 31, wherein at least two of the insulation displacement contacts have stems that are crossed.