Capacitive and inductive coupling connector

• US 5,432,486 A
• Filed: 05/20/1993
• Issued: 07/11/1995
• Est. Priority Date: 05/20/1993
• Status: Expired due to Term

• Current Assignee: Avaya Incorporated
• Original Assignee: Northern Telecom Limited (Nortel Networks Corporation)
• Inventors: Wong, Larry K.-C.
• Primary Examiner(s): GENSLER, PAUL L
• Application Number:
  US08/064,284
• Time in Patent Office: 782 Days
• Field of Search: 333/109, 333/116, 333/260, 333/24 R, 333/24 C, 439/67, 439/77, 361/749, 361/750, 361/789
• US Class Current: 333/109
• CPC Class Codes: H01R 12/62 connecting to rigid printed circuits or like structures
• CPC Class Codes: H01R 12/79 connecting to rigid printed circuits or like structures
• CPC Class Codes: H01R 13/658 High frequency shielding arrangements, e.g. against EMI [Electro-Magnetic Interference] or EMP [Electro-Magnetic Pulse] coaxial coupling devices specially adapted for high frequency H01R24/40; for flat or ribbon cable connectors H01R12/774; for coaxial cable H01R9/05
• CPC Class Codes: H01R 13/6633 with inductive component, e.g. transformer
• CPC Class Codes: H05K 1/0239 Signal transmission by AC coupling
• CPC Class Codes: H05K 1/0246 Termination of transmission lines
• CPC Class Codes: H05K 1/118 specially for flexible printed circuits, e.g. using folded portions
• CPC Class Codes: H05K 1/14 Structural association of two or more printed circuits providing electric connection to or between printed circuits H05K1/11, H01R12/00
• CPC Class Codes: H05K 2201/044 Details of backplane or midplane for mounting orthogonal PCBs
• CPC Class Codes: H05K 2201/10022 Non-printed resistor
• CPC Class Codes: H05K 3/28 Applying non-metallic protective coatings H05K3/0091 takes precedence; methods for intermediate insulating layers for build-up multilayer circuits H05K3/4673
• CPC Class Codes: H05K 3/361 Assembling flexible printed circuits with other printed circuits

Abstract

A coupling connector relies on inductive and capacitive coupling over a length L_c to "connect" signals from a first circuit card to a second circuit card. The coupling connector includes a flex circuit which in a connected state is compressed to provide a coupling length L_c between the first and second circuit cards. A typical application is for coupling cards to a backplane having a plurality of parallel, signal carrying tracks. The near end of each coupling track is input to a receiver having an input impedance equal to the characteristic impedance of the coupling track. The far end of the coupling track is terminated by a resistor whose value equals the characteristic impedance of the coupling track.

Claims

1. A coupling connector for coupling a first circuit to a second circuit having at least one conductive track disposed thereon comprising:

a circuit board for providing the first circuit;

a flex circuit having at least one conductive track disposed thereon and an electrically insulating layer coating the conductive track and attached to the circuit board;

a receiver of the first circuit disposed on the circuit board and connected to one end of the conductive track;

a termination resistor disposed on the circuit board and connected to the other end of the conductive track; and

means for registering the conductive track of the flex circuit with the conductive track of the second circuit and for maintaining the conductive track of the flex circuit proximate to the conductive track of the second circuit for a predetermined length;

said electrically insulating later preventing direct electrical contact between the conductive tracks.

2. A coupling connector as claimed in claim 1 wherein the means for registering and maintaining includes a pin box connector mounted on the circuit board.

3. A coupling connector as claimed in claim 2 wherein the means for registering and maintaining includes two pin box connectors mounted on the circuit board with the flex circuit therebetween.

4. A backplane assembly comprising:

a backplane printed circuit board having a plurality of substantially parallel conductive tracks; and

a coupling connector for coupling a first circuit via the backplane to a second circuit and having at least one conductive track comprising;

a circuit board for providing the first circuit;

a flex circuit having at least one conductive track disposed thereon and an electrically insulated layer coating the conductive track and attached to the circuit board;

a receiver of the first circuit disposed on the circuit board and connected to one end of the conductive track;

a termination resistor disposed on the circuit board and connected to the other end of the conductive track; and

means for registering the conductive track of the flex circuit with the conductive track of the second circuit and for maintaining the conductive track of the flex circuit proximate to the conductive track of the second circuit for a predetermined length;

said electrically insulating layer preventing direct electrical contact between the conductive tracks.

5. A backplane assembly as claimed in claim 4 wherein the means for registering and maintaining includes a pin box connector mounted on the circuit board.

6. A backplane assembly as claimed in claim 5 wherein the means for registering and maintaining includes two pin box connectors mounted on the circuit board with the flex circuit therebetween.

7. A backplane assembly as claimed in claim 4 wherein each of the plurality of substantially parallel conductive tracks is driven at first ends by a driver and terminated at second ends by a termination resistor, the first ends being adjacent to the end of the conductive track of the flex circuit to which the receiver is connected.

8. A backplane assembly as claimed in claim 4 wherein the flex circuit includes a plurality of conductive tracks.

9. A coupling connector for coupling a first circuit to a second circuit having at least one conductive track comprising:

two circuit boards;

a flex circuit having at least one conductive track disposed thereon and an electrically insulating layer coating the conductive track and having each of its ends attached to a respective circuit board;

a receiver of the first circuit disposed on one circuit board and connected to one end of the conductive track;

a termination resistor disposed on the other circuit board and connected to the other end of the conductive track; and

means for registering the conductive track of the flex circuit with the conductive track of the second circuit and for maintaining the conductive track of the flex circuit proximate to the conductive track of the second circuit for a predetermined length;

said electrically insulating layer preventing direct electrical contact between the conductive tracks.

10. A coupling connector as claimed in claim 9 wherein each of the two circuit boards comprises two printed circuits and the flex circuit is attached thereto by sandwiching it between the two printed circuits.