PCB planar transformer and converter using the same

• US 10,128,760 B2
• Filed: 09/01/2015
• Issued: 11/13/2018
• Est. Priority Date: 11/12/2014
• Status: Active Grant

• Current Assignee: Delta Electronics Incorporated
• Original Assignee: Delta Electronics Incorporated
• Inventors: Song, Haibin, Zhou, Jian
• Primary Examiner(s): Chan, Tsz
• Application Number:
  US14/841,729
• Publication Number:
  US 20160134195A1
• Time in Patent Office: 1,169 Days
• Field of Search: 336 84 R, 336 84 C, 336 84 M, 336200, 336232
• CPC Class Codes: H01F 27/2804 Printed windings
• CPC Class Codes: H01F 27/2885 with shields or electrodes shields or electrodes for pancake coils H01F27/2871; construction of electric or magnetic shields or screens H01F27/36
• CPC Class Codes: H02M 3/335 using semiconductor devices only
• CPC Class Codes: H02M 3/33507 with automatic control of the output voltage or current, e.g. flyback converters H02M3/33561, H02M3/33569 take precedence

Abstract

A PCB planar transformer, comprising: at least one primary winding layer, each formed with a primary winding therein, wherein wire traces constituting the primary winding have a first horizontal width; at least one secondary winding layer, each formed with a secondary winding therein, wherein wire traces constituting the secondary winding have a second horizontal width; and at least one shielding layer, each located between the primary winding layer and the adjacent secondary winding layer, wherein the shielding layer is formed with a conductor therein, and the conductor in the shielding layer has a third horizontal width, wherein at least one of the first horizontal and the second horizontal width is smaller than the third horizontal width of the conductor in the shielding layer.

Claims

1. A PCB planar transformer, comprising:

at least one primary winding layer, each formed with a primary winding therein, wherein wire traces constituting the primary winding have a first horizontal width;

at least one secondary winding layer, each formed with a secondary winding therein, wherein wire traces constituting the secondary winding have a second horizontal width; and

at least one shielding layer, each located between the primary winding layer and the adjacent secondary winding layer, wherein the shielding layer is formed with a conductor therein, and the conductor in the shielding layer has a third horizontal width,

wherein the first horizontal width is smaller than the third horizontal width of the conductor in the shielding layer and the third horizontal width of the conductor in the shielding layer is smaller than the second horizontal width, wherein at least one of a difference value between the third horizontal width and the first horizontal width and a difference value between the third horizontal width and the second horizontal width is bigger than 0.3 mm.

2. The PCB planar transformer according to claim 1, wherein the wire traces of the primary winding and the wire traces of the secondary winding do not directly face each other.

3. The PCB planar transformer according to claim 1, wherein the second horizontal width is smaller than the third horizontal width, and the first horizontal width is larger than or equal to the third horizontal width.

4. The PCB planar transformer according to claim 1, wherein both the first horizontal width and the second horizontal width are smaller than the third horizontal width.

5. The PCB planar transformer according to claim 1, wherein the wire traces of the primary winding, the wire traces of the secondary winding and the conductor in the shielding layer are center-aligned with each other.

6. The PCB planar transformer according to claim 1, wherein at least one of the primary winding layer and the secondary winding layer has more than one layer.

7. The PCB planar transformer according to claim 6, wherein the secondary winding layer has two layers respectively located above and below the primary winding layer, and the shielding layer has two layers respectively located between the primary winding layer and the adjacent secondary winding layer.