Self-canceling magnetic structures for transferring power and communication signals
A structure comprises a plurality of first turns of a coil and a plurality of second turns of the coil having a similar shape as the plurality of first turns of the coil, wherein the plurality of first turns of the coil and the plurality of second turns of the coil have a similar center position and a current flowing through the plurality of first turns of the coil and a current flowing through the plurality of second turns of the coil are in opposite directions.
1. A structure comprising:
a plurality of first turns of a coil, wherein the plurality of first turns is formed by a first continuous conductive element; and
a plurality of second turns of the coil having a similar shape as the plurality of first turns of the coil, wherein:
the plurality of second turns is formed by a second continuous conductive element;
the plurality of first turns of the coil and the plurality of second turns of the coil have a similar center position; and
a current flowing through the plurality of first turns of the coil and a current flowing through the plurality of second turns of the coil are in opposite directions.
2. The structure of claim 1 , wherein:
the plurality of first turns of the coil is circular in shape.
3. The structure of claim 2 , wherein:
the plurality of first turns of the coil starts from a first terminal of the coil and ends at a connection element; and
the plurality of second turns of the coil starts from the connection element and ends at a second terminal of the coil, and wherein:
the plurality of second turns of the coil is surrounded by the plurality of first turns of the coil; and
the first terminal and the second terminal are placed immediately next to each other.
4. The structure of claim 1 , wherein:
a turn in the plurality of first turns of the coil has a slightly different shape from a turn in the plurality of second turns of the coil.
5. The structure of claim 1 , wherein:
the plurality of first turns of the coil is rectangular in shape.
6. The structure of claim 1 , wherein:
the plurality of first turns of the coil is octagonal in shape.
7. The structure of claim 1 , further comprising:
a plurality of third turns of the coil and a plurality of fourth turns of the coil, wherein:
the plurality of third turns of the coil and the plurality of fourth turns of the coil have a similar shape and a similar center position; and
a current flowing through the plurality of third turns of the coil and a current flowing through the plurality of fourth turns of the coil are in opposite directions.
8. The structure of claim 7 , wherein:
the plurality of first turns of the coil and the plurality of second turns of the coil are placed on a first layer of a printed circuit board; and
the plurality of third turns of the coil and the plurality of fourth turns of the coil are placed on a second layer of the printed circuit board.
9. The structure of claim 8 , further comprising:
a via in the printed circuit board and connected between the plurality of second turns of the coil and the plurality of third turns of the coil.
10. A system comprising:
a first coil having a first winding structure comprising:
a plurality of first turns and a plurality of second turns of the first coil having a similar shape, wherein:
the plurality of first turns and the plurality of second turns have a similar center position; and
a current flowing through the plurality of first turns and a current flowing through the plurality of second turns are in opposite directions; and
a second coil having a plurality of turns, wherein the first coil and the second coil are two continuous conductive elements.
11. The system of claim 10 , wherein:
the first coil is placed inside the second coil.
12. The system of claim 10 , wherein:
the first coil is placed outside the second coil.
13. The system of claim 10 , wherein:
one of the first coil and the second coil is configured to transfer power.
14. The system of claim 10 , wherein:
one of the first coil and the second coil is configured to transfer communication signals.
15. The system of claim 10 , wherein:
one of the first coil and the second coil is configured to transfer both power and communication signals.
16. A method comprising:
wirelessly transferring power from a transmitting coil on a transmitter to a receiving coil on a receiver, wherein each of the transmitting coil and the receiving coil comprises:
a plurality of first turns and a plurality of second turns having a similar shape, and wherein a current flowing through the plurality of first turns and a current flowing through the plurality of second turns are in opposite directions; and
communicating between the transmitter and the receiver through a communication coil having an 8-shaped structure comprising a first half circle and a second half circle.
17. The method of claim 16 , wherein:
the step of communicating between the transmitter and the receiver is achieved by modulating a circuit parameter or an operation parameter of the transmitter.
18. The method of claim 17 , wherein:
the communicating between the transmitter and the receiver is through the communication coil placed at the transmitter.
19. The method of claim 16 , wherein:
the step of communicating between the transmitter and the receiver is achieved by modulating a circuit parameter or an operation parameter of the receiver.
20. The method of claim 19 , wherein:
the communicating between the transmitter and the receiver is through the communication coil placed at the receiver.