PACKAGING STRUCTURE OF A MAGNETIC DEVICE

• US 20160141087A1
• Filed: 11/15/2015
• Published: 05/19/2016
• Est. Priority Date: 01/10/2013
• Status: Active Grant

• Current Assignee: Cyntec Co. Ltd. (Delta Electronics Incorporated)
• Original Assignee: Cyntec Co. Ltd. (Delta Electronics Incorporated)
• Inventors: Wu, Tsung-Chan, Lee, Chi-Hsun, Liu, Chun-Tiao, Hsieh, Lan-Chin, Chuang, Chih-Siang
• Granted Patent: US 9,959,965 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01F 1/14741 pressed, sintered or bonded together
• CPC Class Codes: H01F 1/14766 Fe-Si based alloys
• CPC Class Codes: H01F 1/14791 Fe-Si-Al based alloys, e.g. Sendust
• CPC Class Codes: H01F 17/045 with core of cylindric geometry and coil wound along its longitudinal axis, i.e. rod or drum core
• CPC Class Codes: H01F 27/022 Encapsulation
• CPC Class Codes: H01F 27/255 made from particles H01F27/26 takes precedence
• CPC Class Codes: H01F 27/2828 Construction of conductive connections, of leads
• CPC Class Codes: H01F 27/29 Terminals; Tapping arrangements for signal inductances

Abstract

An inductor is disclosed, the inductor comprising: a T-shaped magnetic core, being made of a material comprising an annealed soft magnetic metal material and having a base and a pillar integrally formed with the base, wherein the volume of the base is V1 and the volume of the pillar is V2; a coil wound on the pillar; and a magnetic body encapsulating the pillar, the coil and a portion of the base, wherein the ratio of V1 to V2 (V1/V2) is configured in a pre-determined range so as to reduce the total core loss of the inductor with the equivalent permeability of the inductor being between 28.511 and 52.949.

Claims

1. An inductor comprising:

a T-shaped magnetic core, being made of a material comprising an annealed soft magnetic metal material and having a base and a pillar integrally formed with the base, the base having a top side and a bottom side opposite to the top side, the pillar being located on the top side of the base, wherein the volume of the base is V1 and the volume of the pillar is V2;

a coil wound on the pillar; and

a magnetic body encapsulating the pillar, the coil and a portion of the base with a bottom surface of the base being not covered by the magnetic body, wherein the ratio of V1 to V2 (V1/V2) is configured in a pre-determined range so as to reduce the total core loss of the inductor with the equivalent permeability of the inductor being between 28.511 and 52.949.

2. The inductor of claim 1, wherein the inductor is a choke.

3. The inductor of claim 1, wherein V1/V2≦

2.533, and the total core loss of the inductor is not greater than 695.02 mW.

4. The inductor of claim 1, wherein V1/V2≦

2.093, and the total core loss of the inductor is not greater than 483.24 mW.

5. The inductor of claim 1, wherein the annealed soft magnetic metal material comprising Fe—

Si alloy powder that has been pressed into a T-shaped structure and annealed to have the permeability between 48 and 108.

6. The inductor of claim 1, wherein the annealed soft magnetic metal material comprising Fe—

Si—

Al alloy powder that has been pressed into the T-shaped structure and annealed to have the permeability between 48 and 150.

7. The inductor of claim 1, wherein the annealed soft magnetic metal material comprising Fe—

Ni alloy powder that has been pressed into the T-shaped structure and annealed to have the permeability between 48 and 192.

8. The inductor of claim 1, wherein the annealed soft magnetic metal material comprising Fe—

Ni—

Mo alloy powder that has been pressed into the T-shaped structure and annealed to have the permeability between 48 and 240.

9. The inductor of claim 1, wherein two electrodes are embedded in the base, said two electrodes being electrically connected to two leads of the coil.

10. The inductor of claim 9, wherein a bottom surface of each of the two electrodes is substantially coplanar with the bottom surface of the base, and a lateral surface of each of the two electrodes is substantially coplanar with a corresponding one of two opposite lateral surfaces of the base.

11. The inductor of claim 9, wherein the base has two recesses respectively located on two lateral sides of the base, the two recesses respectively receiving said two leads of the coil so that the two leads are respectively in contact with the two electrodes via the two recesses.

12. The inductor of claim 1, wherein the coil is a pre-wound hollow coil having two integral leads, wherein said two integral leads of the pre-wound hollow coil extend outside of the body of the inductor for connecting with an external circuit.

13. A magnetic device comprising:

a T-shaped magnetic core including a base and a pillar integrally formed with the base, the base having a top side and a bottom side opposite to the top side, the pillar being located on the top side of the base and having a top portion away from the base;

a pre-wound hollow coil having two integral leads, wherein at least one portion of the pillar is disposed inside the pre-wound hollow coil; and

a magnetic body encapsulating the pillar, the pre-wound hollow coil and a portion of the base, wherein a portion of the magnetic body is overlaid on the top portion of the pillar and a bottom surface of the bottom side of the base is not covered by the magnetic body, wherein said portion of the magnetic body overlaid on the top portion of the pillar is extended to contact a portion of the pre-wound hollow coil, wherein the magnetic body and the bottom surface of the base forms outer surfaces of the magnetic device, wherein the two integral leads of the pre-wound hollow coil extend outside of said outer surfaces of the magnetic device for forming two electrodes of the magnetic device for connecting with an external circuit.

14. The magnetic device of claim 13, wherein the two integral leads of the pre-wound hollow coil extend outside of said outer surfaces of the magnetic device through a same side surface of the magnetic body, the two integral leads being used as two through-hole pins of the magnetic device for connecting with an external circuit.

15. The magnetic device of claim 13, wherein the two integral leads of the pre-wound hollow coil extend outside of the said outer surfaces of the magnetic device through two opposite side surfaces of the magnetic body respectively, the two integral leads being used as two through-hole pins of the magnetic device for connecting with an external circuit.

16. The magnetic device of claim 13, wherein the base has a first through hole and a second through hole along two opposite lateral surfaces of the base respectively, wherein the two integral leads of the pre-wound hollow coil extend outside of said outer surfaces of the magnetic device through the first through hole and the second through hole respectively.

17. The magnetic device of claim 13, wherein said portion of the magnetic body overlaid on the top portion of the pillar is further extended to a plane coplanar with the bottom surface of the base.

18. The magnetic device of claim 13, wherein the base has two through holes located on two lateral sides of the base respectively, wherein the two integral leads of the pre-wound hollow coil respectively pass the two through holes for forming two electrodes of the magnetic device for connecting with an external circuit.

19. The magnetic device of claim 13, each of the two integral leads of the pre-wound hollow coil extends out of a lateral surface of the magnetic body to form two through-hole pins of the magnetic device for connecting with an external circuit.

20. The magnetic device of claim 13, wherein the magnetic core is made of an annealed soft magnetic metal material.