Surface mounted array strain relief device

• US 4,764,848 A
• Filed: 11/24/1986
• Issued: 08/16/1988
• Est. Priority Date: 11/24/1986
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Simpson, John P.
• Primary Examiner(s): Kucia, R. R.
• Application Number:
  US06/934,297
• Time in Patent Office: 631 Days
• Field of Search: 174/52 FP, 361/408, 361/421, 339/17 CF, 439/61, 439/80, 439/81
• US Class Current: 361/776
• CPC Class Codes: H05K 1/0271 Arrangements for reducing stress or warp in rigid printed circuit boards, e.g. caused by loads, vibrations or differences in thermal expansion
• CPC Class Codes: H05K 2201/09418 Special orientation of pads, lands or terminals of component, e.g. radial or polygonal orientation
• CPC Class Codes: H05K 2201/10704 Pin grid array [PGA]
• CPC Class Codes: H05K 2201/10757 Bent leads
• CPC Class Codes: H05K 3/3426 characterised by the leads
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

An electrical assembly having an integrated circuit package which has a plurality of electrical conductors fixed thereto. The electrical conductors form mechanical and electrical connections. Each of the electrical conductors has a root at one end and a tip at the other end. The root of each conductor is attached to the integrated circuit package to form a fixed electrical and mechanical connection. The tip of each conductor is adapted to be connected to a surface at a predetermined location. Each of the electrical conductors has at least two bends between the root and the tip for providing strain relief when the tip is connected to a surface.

Claims

1. An electrical assembly comprising:

(a) a printed circuit board having at least one major surface having predetermined locations thereon which are adapted to receive electrical conductors;

(b) a substantially planar integrated circuit package having a plurality of electrical conductors fixed thereto and extending therefrom so as to form mechanical and electrical connections between said printed circuit board and said integrated circuit package, said integrated circuit package having a central area and a periphery surrounding said central area, some of said plurality of electrical conductors being fixed to said central area; and

(c) each of said electrical conductors located within said integrated circuit package and extending therefrom and having a root at one end, a curved knee portion, and a tip at the other end thereof, each of said conductors being attached at said root to said integrated circuit package and at said tip to said printed circuit board to form said fixed electrical and mechanical connection, said root and said tip of each of said electrical conductors lying along the same axis perpendicular to the plane formed by said integrated circuit package, each of said electrical connectors providing strain relief between said printed circuit board and said integrated circuit package components of said electrical assembly to accommodate for forces applied to said components in at least three directions while maintaining said mechanical and electrical connections.

2. The electrical assembly in accordance with claim 1 wherein the locations of said roots of said plurality of electrical conductors form a cartesian matrix on said integrated circuit package.

3. The electrical assembly in accordance with claim 2 wherein the planes of said electrical conductor knees are non-orthogonal with respect to said matrix of electrical conductor roots.

4. The electrical assembly in accordance with claim 2 wherein said knee of predetermined electrical conductors is adapted to mesh with a knee of other predetermined electrical conductors.

5. The electrical assembly in accordance with claim 1 wherein said integrated circuit package and said printed circuit board are both substantially planar and the plane of said integrated circuit package is substantially parallel to the plane of said printed circuit board.

6. The electrical assembly in accordance with claim 1 wherein the cross-section of each of said electrical conductors is non-rectilinear.

7. The electrical assembly in accordance with claim 6 wherein the cross-section of each of said electrical conductors is a polygon having five or more sides.

8. The electrical assembly in accordance with claim 6 wherein the cross-section of each of said electrical conductors is substantially circular.

9. The electrical assembly in accordance with claim 1 wherein said tip of each electrical conductor is fixedly connected by solder to one of said predetermined locations on the surface of said printed circuit board.

10. The electrical assembly in accordance with claim 1 wherein said tip of each electrical conductor is fixedly connected by bonding to one of said predetermined locations on the surface of said printed circuit board.

11. The electrical assembly in accordance with claim 1 wherein the locations of said roots of said plurality of electrical conductors form a polar matrix on said integrated circuit package.

12. The electrical assembly in accordance with claim 11 wherein the planes of said electrical conductor knees are substantially radial.

13. The electrical assembly in accordancae with claim 12 wherein said knee of predetermined electrical conductors is adapted to mesh with a knee of other predetermined electrical conductors.

14. The electrical assembly in accordance with claim 10 wherein the locations of said roots of said plurality of electrical conductors form a cartesian matrix on said integrated circuit package.

15. The electrical assembly in accordance with claim 14 wherein the axes of said electrical conductor knees are non-orthogbnal with respect to said matrix of electrical conductor roots.

16. The electrical assembly in accordance with claim 14 wherein said knee of predetermined electrical conductors is adapted to mesh with a knee of other predetermined electrical conductors.

17. An electrical assembly comprising:

(a) an integral circuit package having a plurality of electrical conductors fixed thereto and extending therefrom so as to form mechanical and electrical connections between said package and an external surface when said conductors are attached thereto, said integrated circuit package having a central area and a periphery surrounding said central area, some of said plurality of electrical conductors being fixed to said control area; and

(b) each of said electrical conductors located within said integrated circuit package and having a root at one end attached to said package and a tip at the other end thereof adapted to be fixedly connected to said external surface at a predetermined location thereon, each of said electrical conductors having a curved knee portion including at least two bends said root and said tip for providing strain relief between said integrated circuit package and said external surface when said tip is connected to said surface to accommodate for forces applied to said package and surface in at least three directions while maintaining said mechanical and electrical connections.

18. The electrical assembly in accordance with claim 17 wherein said root and said top of each of said electrical conductors lie along the same plane perpendicular to the plane formed by said integrated circuit package.

19. The electrical assembly in accordance with claim 17 wherein the cross-section of each of said electrical conductors is non-rectilinear.

20. The electrical assembly in accordance with claim 19 wherein the cross-section of each of said electrical conductors is a polygon having five or more sides.

21. The electrical assembly in accordance with claim 19 wherein the cross-section of each of said electrical conductors is substantially circular.

22. The electrical assembly in accordance with claim 21 wherein the locations of said roots of said plurality of electrical conductors form a polar matrix on said integrated circuit package.

23. The electrical assembly in accordance with claim 22 wherein the planes of said electrical conductor knees are substantially radial.

24. The electrical assembly in accordance with claim 23 wherein said knee of predetermined electrical conductors is adapted to mesh with a knee of other predetermined electrical conductors.