Charge dissipative electrical interconnect

• US 20060022789A1
• Filed: 05/23/2005
• Published: 02/02/2006
• Est. Priority Date: 05/26/2004
• Status: Abandoned Application

• Current Assignee: The United States of America As Represented By The Secretary of Agriculture
• Original Assignee: The United States of America As Represented By The Secretary of Agriculture
• Inventors: Wollack, Edward J., Kolasinski, John R.
• Application Number:
  US11/136,766
• Publication Number:
  US 20060022789A1
• Time in Patent Office: Days
• US Class Current: 337/14
• CPC Class Codes: H01B 11/1058 using a coating, e.g. a loaded polymer, ink or print
• CPC Class Codes: H01B 11/1091 with screen grounding means, e.g. drain wires
• CPC Class Codes: H01B 9/027 composed of semi-conducting layers
• CPC Class Codes: H05K 1/0215 Grounding of printed circuits by connection to external grounding means
• CPC Class Codes: H05K 1/0218 by printed shielding conductors, ground planes or power plane H05K1/0236 takes precedence
• CPC Class Codes: H05K 1/0259 Electrostatic discharge [ESD] protection
• CPC Class Codes: H05K 1/167 incorporating printed resistors
• CPC Class Codes: H05K 3/4626 characterised by the insulating layers or materials H05K3/4688 takes precedence

Abstract

A charge-dissipative electrical interconnect comprises at least one first conductive element, a first lossy dielectric layer surrounding the at least one first conductive element, a first shielding element surrounding the first lossy dielectric layer, at least one grounding conductive element electrically contacting the first shielding element, and a second lossy dielectric layer surrounding the first shielding element.

Claims

1. A charge-dissipative electrical interconnect, comprising:

at least one first conductive element;

a first lossy dielectric layer surrounding the at least one first conductive element;

a first shielding element surrounding the first lossy dielectric layer;

at least one grounding conductive element electrically contacting the first shielding element; and

a second lossy dielectric layer surrounding the first shielding element.

2. The charge-dissipative electrical interconnect of claim 1, wherein the at least one grounding conductive element is disposed between the first lossy dielectric layer and the first shielding element.

3. The charge-dissipative electrical interconnect of claim 1, wherein the first shielding element is disposed between the first lossy dielectric layer and the at least one grounding conductive element.

4. The charge-dissipative electrical interconnect of claim 1, wherein the at least one grounding conductive element is in electrical contact with one of the first lossy dielectric layer and the second lossy dielectric layer.

5. The charge-dissipative electrical interconnect of claim 1, wherein the at least one first conductive element is configured to transmit an electrical signal.

6. The charge-dissipative electrical interconnect of claim 1, wherein the at least one grounding conductive element is configured to transfer charge from at least one of the first lossy dielectric layer, the second lossy dielectric layer, and the shielding element, to a reference element.

7. The charge-dissipative electrical interconnect of claim 1, wherein the first shielding element comprises at least one of a metal foil and a metal wire braid.

8. The charge-dissipative electrical interconnect of claim 7, wherein the first shielding element comprises silver-plated copper.

9. The charge-dissipative electrical interconnect of claim 1, wherein the lossy dielectric comprises a thermoplastic polyester elastomer.

10. The charge-dissipative electrical interconnect of claim 9, wherein the thermoplastic polyester elastomer comprises a crystalline hard segment and an amorphous soft segment.

11. The charge-dissipative electrical interconnect of claim 10, wherein the thermoplastic polyester elastomer comprises butylene/poly(alkylene ether)phthalate.

12. The charge-dissipative electrical interconnect of claim 1, wherein the lossy dielectric has a resistivity ranging from approximately 1×

10⁸ Ω

-m to approximately 1×

10¹¹ Ω

-m.

13. The charge-dissipative electrical interconnect of claim 12, wherein the lossy dielectric has a resistivity of approximately 1×

10⁹ Ω

-m.

14. The charge-dissipative electrical interconnect of claim 1, wherein the at least one grounding conductive element has a lower impedance than the at least one first conductive element relative to a reference element.

15. The charge-dissipative electrical interconnect of claim 14, wherein the at least one grounding conductive element has an impedance of less than about 10 Ω

and the at least one first conductive element has an impedance of greater than about 50 Ω

relative to the reference element.

16. The charge-dissipative electrical interconnect of claim 15, wherein the at least one grounding conductive element has an impedance of approximately 1 Ω

and the at least one first conductive element has an impedance of approximately 75 Ω

relative to the reference element.

17. The charge-dissipative electrical interconnect of claim 1, wherein the at least one first conductive element comprises a plurality of first conductive elements.

18. The charge-dissipative electrical interconnect of claim 17, wherein each first conductive element is surrounded by a discrete first lossy dielectric layer.

19. The charge-dissipative electrical interconnect of claim 18, wherein the charge-dissipative electrical interconnect comprises a cable.

20. The charge-dissipative electrical interconnect of claim 18, wherein each first lossy dielectric layer is in electrical contact with at least one of a grounding conductive element and a first lossy dielectric layer that is in electrical contact with a grounding conductive element.

21. The charge-dissipative electrical interconnect of claim 18, further comprising a second shielding element substantially within the first shielding element.

22. The charge-dissipative electrical interconnect of claim 21, wherein the second shielding element surrounds at least one first conductive element and at least one grounding conductive element.

23. The charge-dissipative electrical interconnect of claim 17, wherein the first conductive elements are surrounded by a common first lossy dielectric layer.

24. The charge-dissipative electrical interconnect of claim 23, wherein the common first lossy dielectric layer comprises a substantially continuous coating on the first conductive elements.

25. The charge-dissipative electrical interconnect of claim 23, wherein the charge-dissipative electrical interconnect comprises a ribbon cable.

26. The charge-dissipative electrical interconnect of claim 23, further comprising an insulated cover disposed on the second lossy dielectric layer.

27. The charge-dissipative electrical interconnect of claim 26, wherein the charge-dissipative electrical interconnect comprises an electrical connector.

28. The charge-dissipative electrical interconnect of claim 23, further comprising a substrate supporting the plurality of first conductive elements.

29. The charge-dissipative electrical interconnect of claim 28, wherein the plurality of first conductive elements comprise leads for at least one integrated circuit.

30. The charge-dissipative electrical interconnect of claim 29, wherein the charge-dissipative electrical interconnect comprises at least a portion of a circuit board.

31. The charge-dissipative electrical interconnect of claim 17, wherein the at least one grounding conductive element comprises a plurality of grounding conductive elements.

54. The charge-dissipative electrical interconnect of claim 1, wherein the at least one grounding conductive element electrically contacts the first shielding element along substantially the entire interconnect.

55. The charge-dissipative electrical interconnect of claim 1, wherein the at least one grounding conductive element electrically contacts the first shielding element only at end portions of the interconnect.

32. A charge-dissipative electrical interconnect, comprising:

a plurality of first conductive elements;

a first lossy dielectric layer surrounding the first conductive elements;

a first shielding element surrounding the first lossy dielectric layer;

a second lossy dielectric layer surrounding the first shielding element; and

at least one grounding conductive element in electrical contact with the first shielding element and at least one of the first lossy dielectric layer and the second lossy dielectric layer.

33. The charge-dissipative electrical interconnect of claim 32, wherein each first conductive element is surrounded by a discrete first lossy dielectric layer.

34. The charge-dissipative electrical interconnect of claim 33, wherein the first conductive elements and the at least one grounding conductive element are arranged in a cable to form a substantially circular array in cross-section.

35. The charge-dissipative electrical interconnect of claim 34, further comprising a second shielding element within the first shielding element.

36. The charge-dissipative electrical interconnect of claim 35, wherein the second shielding element surrounds at least one first conductive element and at least one grounding conductive element.

37. The charge-dissipative electrical interconnect of claim 32, wherein the at least one grounding conductive element comprises a plurality of grounding conductive elements.

38. The charge-dissipative electrical interconnect of claim 32, wherein the at least one grounding conductive element is configured to transfer charge from at least one of the first lossy dielectric layer, the second lossy dielectric layer, and the shielding element, to a reference element.

39. The charge-dissipative electrical interconnect of claim 32, wherein the first shielding element comprises at least one of a metal foil and a metal wire braid.

40. The charge-dissipative electrical interconnect of claim 32, wherein the lossy dielectric comprises a thermoplastic polyester elastomer.

41. The charge-dissipative electrical interconnect of claim 40, wherein the thermoplastic polyester elastomer comprises a crystalline hard segment and an amorphous soft segment.

42. The charge-dissipative electrical interconnect of claim 40, wherein the thermoplastic polyester elastomer comprises butylene/poly(alkylene ether) phthalate.

43. The charge-dissipative electrical interconnect of claim 32, wherein the lossy dielectric has a resistivity of approximately 1×

10⁹ Ω

-m.

44. The charge-dissipative electrical interconnect of claim 32, wherein the first conductive elements are surrounded by a common first lossy dielectric layer.

45. The charge-dissipative electrical interconnect of claim 44, wherein the common first lossy dielectric layer comprises a substantially continuous coating on the first conductive elements.

46. The charge-dissipative electrical interconnect of claim 44, wherein the charge-dissipative electrical interconnect comprises a ribbon cable.

47. The charge-dissipative electrical interconnect of claim 44, further comprising an insulated cover disposed on the second lossy dielectric layer.

48. The charge-dissipative electrical interconnect of claim 47, wherein the charge-dissipative electrical interconnect comprises an electrical connector.

49. The charge-dissipative electrical interconnect of claim 44, further comprising a substrate supporting the plurality of first conductive elements.

50. The charge-dissipative electrical interconnect of claim 49, wherein the plurality of first conductive elements comprise leads for at least one integrated circuit.

51. The charge-dissipative electrical interconnect of claim 50, wherein the charge-dissipative electrical interconnect comprises at least a portion of a circuit board.

52. The charge-dissipative electrical interconnect of claim 32, wherein the at least one grounding conductive element is in electrical contact with the first shielding element along substantially the entire interconnect.

53. The charge-dissipative electrical interconnect of claim 32, wherein the at least one grounding conductive element is in electrical contact with the first shielding element only at end portions of the interconnect.