Inductor and electric power supply using it

• US 7,812,702 B2
• Filed: 05/15/2009
• Issued: 10/12/2010
• Est. Priority Date: 05/08/2006
• Status: Active Grant

• Current Assignee: Ibiden Co., Ltd.
• Original Assignee: Ibiden Co., Ltd.
• Inventors: Kato, Shinobu, Kariya, Takashi, Mano, Yasuhiko
• Primary Examiner(s): NGUYEN, TUYEN T
• Application Number:
  US12/466,940
• Publication Number:
  US 20090225525A1
• Time in Patent Office: 515 Days
• Field of Search: 336/65, 336/83, 336/200, 336232-234, 257/531
• US Class Current: 336/200
• CPC Class Codes: H01F 17/0006 Printed inductances printed coils for dynamo-electric machines H02K3/26; printed circuits H05K
• CPC Class Codes: H01F 17/06 with core substantially closed in itself, e.g. toroid
• CPC Class Codes: H01F 2017/002 Details of via holes for interconnecting the layers
• CPC Class Codes: H01F 2017/065 Core mounted around conductor to absorb noise, e.g. EMI filter
• CPC Class Codes: H01F 41/046 structurally combined with ferromagnetic material
• CPC Class Codes: H01L 2224/05568 the whole external layer protruding from the surface
• CPC Class Codes: H01L 2224/05573 Single external layer
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/16235 the bump connector connecting to a via metallisation of the item
• CPC Class Codes: H01L 23/645 Inductive arrangements H01L23/647, H01L23/66 take precedence
• 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 2924/01078 Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/01087 Francium [Fr]
• CPC Class Codes: H01L 2924/14 Integrated circuits
• CPC Class Codes: H01L 2924/15312 being a pin array, e.g. PGA
• CPC Class Codes: H01L 2924/1532 the connection portion being formed on the die mounting surface of the substrate
• CPC Class Codes: H01L 2924/3011 Impedance
• CPC Class Codes: H01L 2924/3025 Electromagnetic shielding
• CPC Class Codes: H05K 1/0233 : Filters, inductors or a magnetic substance
• CPC Class Codes: H05K 1/115 : Via connections; Lands around holes or via connections H05K1/112 takes precedence
• CPC Class Codes: H05K 1/185 : Components encapsulated in the insulating substrate of the printed circuit or incorporated in internal layers of a multilayer circuit semiconductor chips encapsulated by interconnect and support structures H01L23/5389, H01L24/00
• CPC Class Codes: H05K 2201/086 : for inductive purposes, e.g. printed inductor with ferrite core
• CPC Class Codes: H05K 2201/09581 : Applying an insulating coating on the walls of holes
• CPC Class Codes: H05K 3/4046 : using auxiliary conductive elements, e.g. metallic spheres, eyelets, pieces of wire
• CPC Class Codes: H05K 3/42 : Plated through-holes or plated via connections
• CPC Class Codes: H05K 3/4602 : characterized by a special circuit board as base or central core whereon additional circuit layers are built or additional circuit boards are laminated
• CPC Class Codes: Y10T 29/4902 : Electromagnet, transformer or inductor

Abstract

An inductor embedded in a printed wiring board includes a conductor extending in the thickness direction of a printed circuit board and a magnetic body that is in contact with the conductor with no gap therebetween. For example, the magnetic body is composed of ferrite having a cylindrical tubular shape. The conductor is composed of a copper film formed by plating on an inner peripheral surface of the cylindrical tubular ferrite. The inductor is inserted in the thickness direction of the printed wiring board.

Claims

1. An electronic device comprising:

a circuit board; and

a power supply circuit provided in the circuit board and configured to supply power to a semiconductor device mounted on a surface of the circuit board,

wherein the power supply circuit includes an inductor extending in a thickness direction of the circuit board perpendicular to the surface of the circuit board, the inductor comprises a magnetic body extending in the thickness direction of the circuit board and a through-hole conductor extending in the thickness direction of the circuit board, the magnetic body of the inductor has a through-hole extending in the thickness direction of the circuit board, and the through-hole conductor of the inductor is formed on an inner surface of the through-hole formed in the magnetic body.

2. The electronic device according to claim 1, wherein the power supply circuit includes a thin-film capacitor formed in a direction parallel to the surface of the circuit board, and a power supply IC device mounted on a surface of the circuit board on an opposite side of the surface on which the semiconductor device is mounted.

3. The electronic device according to claim 1, wherein the power supply circuit includes a thin-film capacitor formed in a direction parallel to the surface of the circuit board and a power supply IC device mounted on a surface of the circuit board on an opposite side of the surface on which the semiconductor device is mounted, and the power supply circuit and the semiconductor device are connected to each other with a conductive circuit having a distance of 1 mm or less.

4. The electronic device according to claim 1, wherein the power supply circuit is provided in a plurality in the circuit board.

5. The electronic device according to claim 1, wherein the circuit board has a core substrate, and the inductor is formed in the core substrate of the circuit board.

6. The electronic device according to claim 1, wherein the magnetic body has a cylindrical shape having the through-hole.

7. The electronic device according to claim 1, wherein the magnetic body has a cylindrical shape, the circuit board has a core substrate, and the magnetic body is embedded in the core substrate of the circuit board.

8. The electronic device according to claim 1, wherein the through-hole conductor is extending along a longitudinal axis of the magnetic body.

9. The electronic device according to claim 1, wherein the through-hole conductor is formed by plating.

10. The electronic device according to claim 1, wherein the through-hole conductor is formed by copper plating.

11. The electronic device according to claim 1, wherein the through-hole conductor is formed by plating.

12. The electronic device according to claim 1, wherein the power supply circuit and the semiconductor device are connected to each other with a conductive circuit comprising a plurality of via-hole conductors.

13. The electronic device according to claim 1, wherein the power supply circuit and the semiconductor device are connected to each other with a conductive circuit comprising a plurality of via-hole conductors in a distance of 1 mm or less.