Impedance Controlled LGA Interposer Assembly

• US 20140162472A1
• Filed: 05/21/2013
• Published: 06/12/2014
• Est. Priority Date: 12/12/2012
• Status: Active Grant

• Current Assignee: Amphenol InterCon Systems, Inc. (Amphenol Corporation)
• Original Assignee: Amphenol InterCon Systems, Inc. (Amphenol Corporation)
• Inventors: Walden, John D., Hileman, James S.
• Granted Patent: US 9,172,161 B2
• Time in Patent Office: Days
• US Class Current: 439/66
• CPC Class Codes: H01R 12/714 with contacts abutting directly the printed circuit; Button contacts therefore provided on the printed circuit
• CPC Class Codes: H01R 13/2407 characterized by the resilient means
• CPC Class Codes: H01R 13/2435 with opposite contact points, e.g. C beam
• CPC Class Codes: H01R 13/6473 Impedance matching
• CPC Class Codes: H05K 2201/10378 Interposers
• CPC Class Codes: H05K 3/325 by abutting or pinching, i.e. without alloying process; mechanical auxiliary parts therefor adaptations of leads inserted in holes for press-fit connections H05K3/308

Abstract

An interposer plate assembly having an insulating plate and metal contacts in the plate with contact points above and below the plate and a central portion in the plate. Two cantilever arms extend from the central portion to each contact point. The central portion may form an impedance shield for reducing impedance between adjacent signal contacts.

Claims

1. An interposer plate assembly for forming electrical connections between contacts on opposed substrates, the assembly comprising an insulating plate having a top surface, a bottom surface and a thickness between the top surface and the bottom surface;

and a plurality of one-piece metal contacts, each contact comprising a central portion in the plate, a first contact point spaced from one side of the plate to engage a pad, two first cantilever arms extending from the central portion to the contact point, and an opening through the contact between the arms.

2. The assembly as in claim 1 wherein the central portion of each contact comprises an impedance coupling section.

3. The assembly as in claim 2 wherein the coupling sections are flat.

4. The assembly as in claim 2 wherein each contact point is offset to one side of the central portion.

5. The assembly as in claim 2 wherein the contacts are formed from uniform-thickness metal stock.

6. The assembly as in claim 2 wherein each contact includes a second contact point spaced from the other side of the plate to engage a pad, two second cantilever arms extending from the central portion to the second contact point and an opening through the contact between such arms.

7. The interposer assembly as in claim 2 including a thermoplastic resin body on the coupling section of each contact member.

8. The interposer assembly as in claim 7 wherein each thermoplastic resin body substantially surrounds a coupling section.

9. The assembly as in claim 7 including a number of apertures in the plate, said resin bodies in said apertures.

10. The assembly as in claim 7 wherein the plate includes a number of elongate, side-by-side insulating members, said coupling sections in said members.

11. The assembly as in claim 10 including inter-engageable fastener members on said members, said fastener members securing said members together.

12. The assembly as in claim 1 wherein the plate includes a number of through passages;

and plastic bodies on the contact central portions, said bodies in said passages.

13. The assembly as in claim 12 wherein such plastic bodies are overmolded on the central portions.

14. The assembly as in claim 12 wherein said bodies are movable in said passages.

15. The assembly as in claim 14 wherein each passage includes an angled surface, the contact members or the contacts in the passage extending over said surface.

16. The assembly as in claim 12 wherein each central portion comprises a coupling section.

17. The assembly as in claim 16 wherein each coupling section comprises a uniform-thickness metal plate.

18. The assembly as in claim 16 wherein each coupling section is flat.

19. The assembly as in claim 18 wherein the coupling sections are generally rectangular with side edges at or adjacent the sides of the dielectric bodies.

20. The assembly as in claim 12 wherein each central portion comprises a coupling section extending across a passage.

21. The assembly as in claim 1 wherein each cantilever arm includes a flexible portion located inside the plate.

22. The assembly as in claim 21 wherein each flexible portion includes a reverse bend on one side of the central portion, the contact point on the opposite side of the central portion.

23. An interposer plate assembly for forming electrical connections between contacts on opposed substrates, the assembly comprising an insulating plate having a top surface, a bottom surface, a thickness between the top surface and the bottom surface, and a plurality of through passages extending between the top and bottom surfaces;

and a plurality of contact members, each contact member comprising a metal contact with opposed contact points and a central large area impedance coupling section between the contact points, and an insulating body on the impedance coupling section;

said contact members in said passages with the contact points spaced outwardly from the top and bottom surfaces of the plate, the insulating bodies in the plate and the coupling sections extending between opposed passage walls, wherein the impedance coupling sections reduce impedance in high-frequency signals carried by pairs of adjacent contact members.

24. The assembly as in claim 23 wherein the contact members substantially fill the through passages.

25. The interposer plate assembly as in claim 23 wherein said contact members have a sliding fit in said through passages, said plate and contact members including inter-engaging surfaces for limiting movement of the contact members in the passages.

26. The assembly as in claim 25 wherein each plastic body is located on opposite sides of an impedance coupling section and conforms generally to the shape of the passage to fill the passage.

27. The assembly as in claim 25 wherein each impedance coupling section comprises a uniform-thickness metal plate, and each insulating body comprises a plastic overmolding on the metal plate.

28. The assembly as in claim 27 wherein each plate is flat.

29. The assembly as in claim 23 wherein said passages are arranged in perpendicular rows and columns and each impedance coupling section extends at an acute angle to said rows and columns.

30. The assembly as in claim 29 wherein said angle is about 45°

to both the rows and the columns.

31. The assembly as in claim 23 wherein each contact includes two arms extending between the impedance coupling section and each contact point, and an opening between the arms.

32. The assembly as in claim 31 wherein each arm comprises a reverse bend with a first portion of the arm on one side of an impedance coupling section and a second portion of the arm on the opposite side of the impedance coupling section, and the contact point is on the opposite side of the impedance coupling section.

35. The assembly as in claim 23 wherein one contact member includes two metal contacts.

37. The assembly as in claim 23 wherein each plastic body has a height less than the thickness of the plate.

38. The assembly as in claim 37 wherein each metal contact includes a flexible spring arm extending between a contact point and the impedance coupling section, part of said flexible spring arm located in a through passage.

39. The assembly as in claim 37 wherein each contact member includes two spring arms joined to each contact point, both said spring arms located in a through passage.

40. The assembly as in claim 39 wherein each spring arm includes a reverse bend located in a passage below a plate top or bottom surface.

33. The assembly as in 32 wherein each impedance coupling section comprises a flat plate extending across or substantially across a through passage.

34. The assembly as in claim 33 wherein each plastic body includes side edges and a corner on one side of the impedance coupling section and a flat portion on the opposite side of the impedance coupling section.

36. The assembly as in claim 36 wherein impedance coupling sections in each contact member are laterally offset, and are coplanar or parallel each other.