Magnetic device having a conductive clip

• US 7,688,172 B2
• Filed: 10/05/2005
• Issued: 03/30/2010
• Est. Priority Date: 10/05/2005
• Status: Active Grant

• Current Assignee: Altera Corporation (Intel Corporation)
• Original Assignee: Enpirion, Inc. (Intel Corporation)
• Inventors: Wilkowski, Mathew A., Lotfi, Ashraf W., Liakopoulos, Trifon M., Weld, John D.
• Primary Examiner(s): Mai; Anh T
• Assistant Examiner(s): BAISA, JOSELITO SASIS
• Application Number:
  US11/244,127
• Publication Number:
  US 20070075817A1
• Time in Patent Office: 1,637 Days
• Field of Search: 336/200
• US Class Current: 336/200
• CPC Class Codes: H01F 17/04 with magnetic core
• CPC Class Codes: H01F 2027/2814 with only part of the coil or of the winding in the printed circuit board, e.g. the remaining coil or winding sections can be made of wires or sheets
• CPC Class Codes: H01L 2224/37147 Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2224/40245 the item being metallic
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/49175 Parallel arrangements
• CPC Class Codes: H01L 25/16 the devices being of types provided for in two or more different main groups of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. forming hybrid circuits
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00011 Not relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01015 Phosphorus [P]
• CPC Class Codes: H01L 2924/01033 Arsenic [As]
• CPC Class Codes: H01L 2924/01047 Silver [Ag]
• CPC Class Codes: H01L 2924/10253 Silicon [Si]
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2924/19105 in a side-by-side arrangement on a common die mounting substrate
• CPC Class Codes: H02M 3/003 Constructional details, e.g. physical layout, assembly, wiring or busbar connections

Abstract

A magnetic device that includes a magnetic core having a surface facing a conductive substrate. The magnetic device also includes a conductive clip facing a surface of the magnetic core with ends of the conductive clip electrically coupled to the conductive substrate to cooperatively form a winding therewith about the magnetic core.

Claims

1. A magnetic device, comprising:

a magnetic core having a lower surface adhered to an adhesive on a patterned, conductive leadframe and a planar opposing upper surface; and

a conductive clip with a bare lower surface facing said opposing upper surface of said magnetic core and with ends of said conductive clip bent toward said conductive leadframe about ends of said magnetic core and electrically coupled to said conductive leadframe to cooperatively form a winding therewith about said magnetic core, wherein said conductive leadframe also forms an electrically conductive interconnect layer for a component wire bonded thereto.

2. The magnetic device as recited in claim 1 wherein said conductive clip is about 8 to 12 mils in thickness.

3. The magnetic device as recited in claim 1 wherein said component is a semiconductor die.

4. The magnetic device as recited in claim 1 wherein said magnetic core is formed from manganese zinc ferrite.

5. The magnetic device as recited in claim 1 wherein said conductive leadframe includes leadframe fingers that form terminals for external electrical connections.

6. The magnetic device as recited in claim 1 wherein said adhesive is a die attach adhesive.

7. The magnetic device as recited in claim 1 wherein said magnetic device is an inductor.

8. The magnetic device as recited in claim 1 wherein said conductive clip is soldered to said conductive leadframe.

9. The magnetic device as recited in claim 1 further comprising a gap between said lower surface of said conductive clip and said opposing upper surface of said magnetic core.

10. The magnetic device as recited in claim 1 further comprising an encapsulant about said magnetic device.

11. A magnetic device, comprising:

a magnetic core formed from a bar of magnetic material having a lower surface adhered to an adhesive on a patterned, conductive leadframe and a planar opposing upper surface; and

at least one conductive clip with a bare lower surface placed above said opposing upper surface of said magnetic core and with ends of said at least one conductive clip bent toward and soldered to said conductive leadframe about ends of said magnetic core to cooperatively form a winding therewith about said magnetic core, wherein said conductive leadframe also forms an electrically conductive interconnect layer for a component wire bonded thereto.

12. The magnetic device as recited in claim 11 wherein said bar of magnetic material is formed from manganese zinc ferrite.

13. The magnetic device as recited in claim 11 wherein said conductive leadframe includes leadframe fingers that form terminals for external electrical connections.

14. The magnetic device as recited in claim 11 wherein said component is a semiconductor die.

15. The magnetic device as recited in claim 11 wherein said adhesive is a die attach adhesive.

16. The magnetic device as recited in claim 11 further comprising a gap between said lower surface of said at least one conductive clip and said opposing surface of said magnetic core.

17. The magnetic device as recited in claim 11 further comprising a gap substantially filled with an encapsulant between said lower surface of said at least one conductive clip and said opposing surface of said magnetic core.

18. The magnetic device as recited in claim 11 further comprising an encapsulant about said magnetic device.

19. The magnetic device as recited in claim 11 further comprising an epoxy encapsulant about said magnetic device.

20. The magnetic device as recited in claim 11 wherein said magnetic device is an inductor.