Transformer structure

• US 6,867,678 B2
• Filed: 01/28/2003
• Issued: 03/15/2005
• Est. Priority Date: 01/28/2003
• Status: Expired due to Fees

• Current Assignee: Entrust Power Co., Ltd.
• Original Assignee: Entrust Power Co., Ltd.
• Inventors: Yang, Lee-Lung
• Primary Examiner(s): MAI, ANH T
• Application Number:
  US10/351,995
• Publication Number:
  US 20040145445A1
• Time in Patent Office: 777 Days
• Field of Search: 336/200, 336/223, 336/232, 336/212, 336/83, 336/96, 296/021, 296/06
• US Class Current: 336/200
• CPC Class Codes: H01F 17/0013 with stacked layers
• CPC Class Codes: H01F 27/2804 Printed windings

Abstract

The present invention describes a planar transformer having a plurality of juxtaposed magnetic cores as well as a two-layer printed circuit board for spiralling a plurality of windings. Each arm of a plurality of juxtaposed magnetic cores respectively goes through a corresponding hole in the middle of these windings, to magnetically couple the current in the main winding to the other windings.

Claims

1. A transformer structure, said structure comprising:

at least three juxtaposed conductor traces, wherein a middle of each conductor trace has a hole; and

a core having at least three arms, wherein each arm goes through a corresponding hole.

2. The transformer structure of claim 1, wherein said juxtaposed conductor traces are formed over a two-layer printed circuit board.

3. The transformer structure of claim 1, wherein the conductor traces are wired in a spiral trace.

4. The transformer structure of claim 1, wherein each conductor trace is a multiple-turn winding.

5. The transformer structure of claim 1, wherein the core is a ferrite core.

6. A transformer structure, said structure comprising:

a two-layer printed circuit board with at least three conductor traces and at least three holes, wherein each conductor trace surrounds a corresponding hole; and

a core having at least three arms, wherein each arm goes through a corresponding hole.

7. The transformer structure of claim 6, wherein the core defines a magnetic path through said arms and respectively linking said conductor traces.

8. The transformer structure of claim 6, wherein the conductor traces are wired in a spiral trace.

9. The transformer structure of claim 6, wherein the conductor trace is a multiple-turn winding.

10. The transformer structure of claim 6, wherein the core is a ferrite core.

11. A transformer structure, said structure comprising:

a two-layer printed circuit board with at least three conductor traces and at least three holes, wherein each conductor trace surrounds a corresponding hole; and

a ferrite core having at least three arms, wherein each arm goes through a corresponding hole.

12. The transformer structure of claim 11, wherein the ferrite core defines a magnetic path through said arms and respectively linking said conductor traces.

13. The transformer structure of claim 11, wherein the conductor traces are wired in a spiral trace.