Surface mount magnetic component assembly

• US 7,986,208 B2
• Filed: 04/24/2009
• Issued: 07/26/2011
• Est. Priority Date: 07/11/2008
• Status: Active Grant

• Current Assignee: Eaton Intelligent Power Limited (Eaton Corporation PLC.)
• Original Assignee: Cooper Technologies Company (Eaton Corporation PLC.)
• Inventors: Bogert, Robert James, Yan, Yipeng
• Primary Examiner(s): NGUYEN, TUYEN T
• Application Number:
  US12/429,856
• Publication Number:
  US 20100007451A1
• Time in Patent Office: 823 Days
• Field of Search: 336/65, 336/83, 336/192, 336/200, 336/232
• US Class Current: 336/192
• CPC Class Codes: H01F 17/043 with two, usually identical or nearly identical parts enclosing completely the coil (pot cores)
• CPC Class Codes: H01F 2017/048 with encapsulating core, e.g. made of resin and magnetic powder
• CPC Class Codes: H01F 2027/065 Mounting on printed circuit boards
• CPC Class Codes: H01F 27/263 Fastening parts of the core together
• CPC Class Codes: H01F 27/2828 Construction of conductive connections, of leads
• CPC Class Codes: H01F 27/292 Surface mounted devices

Abstract

A surface mount magnetic component assembly including a magnetic core having a side with a stepped external surface, a coil within the magnetic core, and terminal clips for making electrical connections to the ends of the coil. The ends of the coil extend through the stepped external surface, the terminal clips attach to the stepped external surface, and the external surface is mounted to a circuit board to complete electrical connection with improved reliability. Smaller component sizes with improved manufacturability and consistency result.

Claims

1. A surface mount magnetic component assembly comprising:

a magnetic core defining an external wall having a first substantially planar exterior surface for mounting to a circuit board, the external wall further having a second substantially planar exterior surface adjacent the first substantially planar exterior surface, the second substantially planar exterior surface being depressed relative to the first substantially exterior surface;

wherein the second substantially planar surface is provided with a through hole;

a conductive coil, the coil including first and second ends; and

at least one of the first and second ends extending through the through hole in a direction substantially perpendicular to the first substantially planar exterior surface.

2. The magnetic component assembly of claim 1, wherein the second substantially planar exterior surface extends generally parallel to the first substantially planar exterior surface.

3. The magnetic component assembly of claim 2, wherein the external wall has a first end and a second end opposing the first end, and the second substantially planar exterior surface extends from the first end to the second end.

4. The magnetic component assembly of claim 2, wherein the external wall further comprises a third substantially planar exterior surface extending opposite the second substantially planar exterior surface with the first substantially planar exterior surface separating the second substantially planar exterior surface and the third substantially planar exterior surface.

5. The magnetic component assembly of claim 4, wherein the second and third substantially planar exterior surfaces are substantially coplanar.

6. The magnetic component assembly of claim 1, the external wall having a corner, and the through-hole extending proximate the corner.

11. The magnetic component assembly of claim 1, wherein the magnetic core comprises a first core piece and a second core piece, one of the first and second core piece defining the external wall.

12. The magnetic component assembly of claim 11, wherein the external wall is defined by the first core piece, wherein the external wall comprises a base wall, and upstanding side walls extend from the base wall.

13. The magnetic component assembly of claim 12, wherein the second core piece is substantially planar.

14. The magnetic component assembly of claim 1, wherein the external wall comprises a base wall, and wherein the magnetic core further comprises a first side wall extending from the base wall, and a second side wall extending from the base wall;

and

wherein the first and second side walls are gapped to provide a window in the core.

15. The magnetic component assembly of claim 14, wherein the window is located proximate a corner of the base wall.

16. The magnetic component assembly of claim 1, further comprising at least one terminal clip configured for attachment to the second substantially planar exterior surface of the core.

22. The magnetic component assembly of claim 16, wherein the terminal clip defines a through hole, and one of the first and second ends of the coil is received in the through hole of the terminal clip.

23. The magnetic component assembly of claim 16, wherein the magnetic core further comprises a second wall adjoining the second substantially planar exterior surface, the second side wall including a recess adjacent the second substantially planar exterior surface, and the at least one terminal clip including a locating tab engaged in the recess.

24. The magnetic component assembly of claim 16, wherein the at least one terminal clip comprises a first terminal clip and a second terminal clip, and wherein the first and second ends of the coil attach to the first and second terminal clips, respectively, without wrapping the first and second ends of the coil around the clips.

25. The magnetic component assembly of claim 1, wherein the coil includes a winding portion between the first and second ends, the winding portion comprising a plurality of turns about a winding axis, and the first and second ends extending generally parallel to the winding axis.

26. The magnetic component assembly of claim 25, wherein the coil comprises one of a flat wire and a round wire wound for a number of turns.

27. The magnetic component assembly of claim 25, wherein the winding extends helically and spirally about the coil axis.

28. The magnetic component assembly of claim 1, further comprising a circuit board, wherein the first substantially planar surface rests upon the circuit board.

29. The magnetic component of claim 28, further comprising first and second terminal clips, the first and second terminal clips connected to a circuit path on the surface of the board and also respectively connected to the first and second ends of the coil.

30. The magnetic component of claim 29, the first and second terminals each including a planar bottom section connecting to the circuit path, and a coil section extending in a plane parallel to, but spaced from the planar bottom section.

31. The magnetic component of claim 1, wherein the component is an inductor.

7. A surface mount magnetic component assembly comprising:

a magnetic core defining at least one external side having a stepped surface; and

a conductive coil internal to the magnetic core, the coil including first and second ends; and

at least one of the first and second ends extending through the at least one side;

wherein the stepped surface comprises a first surface, a second surface and a third surface, wherein the second surface is depressed relative to the first surface and wherein the third surface is depressed relative to the second surface.

8. The magnetic component assembly of claim 7, wherein the at least one side has a first corner and a second corner, the third surface located proximate the first corner and the second surface extending from the third surface to the second corner.

9. The magnetic component assembly of claim 8, wherein the at least one side has a third corner diagonally opposed to the first corner, the at least one side comprising a fourth surface extending generally coplanar to the third surface, the fourth surface located proximate the third corner.

10. The magnetic component of assembly claim 7, wherein the stepped surface further comprises a fourth surface extending generally coplanar to the third surface, the third and fourth surface being separated by the first surface.

17. A surface mount magnetic component assembly comprising:

a magnetic core defining at least one external side having a stepped surface; and

a conductive coil internal to the magnetic core, the coil including first and second ends; and

at least one of the first and second ends extending through the at least one side;

at least one terminal clip configured for attachment to the stepped surface of the core;

wherein the at least one terminal clip includes a bottom section extending in a first plane and a coil section extending in a second plane, the first and second plane being parallel to but spaced from one another.

18. The magnetic component assembly of claim 17, wherein the coil section extends internal to the core.

19. The magnetic component assembly of claim 18, wherein the at least one terminal clip defines a slot and a portion of the core being received in the slot between the bottom section and the coil section.

20. The magnetic component assembly of claim 17, wherein the at least one terminal clip comprises first and second terminal clips, the first and second clips being reversed 180°

relative to one another when attached to the core and coil.

21. The magnetic component assembly of claim 17, wherein the at least one terminal clip comprises a third section generally coplanar to the coil section but separated from the terminal section by the bottom section.

32. A surface mount magnetic component assembly comprising:

a magnetic core having a bottom side defined by first, second, third and fourth corners and having a stepped surface extending between the first, second, third and fourth corners;

a conductive coil internal to the magnetic core, the coil including first and second ends, at least one of the first and second ends extending through the bottom side and a portion of the stepped surface; and

first and second terminal clips coupled to the stepped surface and respectively connecting to the first and second ends of the coil.

33. The magnetic component assembly of claim 32, wherein the core defines at least one window proximate one of the first, second, third and fourth corners for connecting one of the first and second coil leads to the one of the first and second terminal clips at a location interior to the core.

36. The magnetic component assembly of claim 32, wherein the coil comprises one of a flat wire and around wire wound about an axis for a number of turns.

37. The magnetic component assembly of claim 32, further comprising a circuit board, the bottom side being surface mounted to the circuit board.

38. The magnetic component of claim 32, wherein at least one of the first and second terminal clips is bilaterally asymmetrical.

39. The magnetic component assembly of claim 32, wherein the component is an inductor.

34. A surface mount magnetic component assembly comprising:

a magnetic core defining at least one external side with first, second, third and fourth corners and having a stepped surface;

a conductive coil internal to the magnetic core, the coil including first and second ends, at least one of the first and second ends extending through the at least one external side; and

first and second terminal clips coupled to the stepped surface and respectively connecting to the first and second ends of the coil;

wherein each of the first and second terminal clips includes a bottom section extending in a first plane and a coil section extending in a second plane, the second plane being parallel to but spaced from the first plane.

35. The magnetic component assembly of claim 34, wherein the first and third corners are diagonally opposite one another, and the coil sections of each of the first and second terminal clip are proximate the first and third corners.