Dual-mode wireless power receiver

• US 9,912,197 B2
• Filed: 08/01/2013
• Issued: 03/06/2018
• Est. Priority Date: 08/03/2012
• Status: Active Grant

• Current Assignee: MediaTek Singapore Pte. Ltd. (MediaTek, Inc.)
• Original Assignee: MediaTek Singapore Pte. Ltd. (MediaTek, Inc.)
• Inventors: Riehl, Patrick Stanley
• Primary Examiner(s): Barnie, Rexford
• Assistant Examiner(s): Shiao, David
• Application Number:
  US13/956,374
• Publication Number:
  US 20140035383A1
• Time in Patent Office: 1,678 Days
• Field of Search: None
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/402 the two or more transmitting or the two or more receiving devices being integrated in the same unit, e.g. power mats with several coils or antennas with several sub-antennas
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices

Abstract

A dual-mode receiver is provided that includes an electromagnetic resonator having one or more inductive elements that are arranged to form a receiver coil and a network of passive components arranged to form a matching network. The electromagnetic resonator includes a first selective frequency defined in a low frequency range and a second selective frequency defined in a high frequency range allowing for a rectification circuit to operate in both the high frequency range and low frequency range making maximum use of active circuits.

Claims

1. A wireless power receiver comprising:

an electromagnetic resonator that includes;

a plurality of inductive elements connected in series and forming receiver coil; and

a network of passive components comprising a plurality of capacitors arranged to form a matching network, the network of passive components comprising a first capacitor in parallel with a first inductive element of the plurality of inductive elements,

wherein the electromagnetic resonator passively resonates at both a first resonant frequency and a second resonant frequency higher than the first resonant frequency to wirelessly receive power to provide to a rectifier.

2. The wireless power receiver of claim 1, further comprising the rectifier, the rectifier being coupled to the network of passive components.

3. The wireless power receiver of claim 2, wherein the network of passive components further comprises a second capacitor in parallel with an input of the rectifier.

4. The wireless power receiver of claim 3, further comprising a third capacitor coupled between the first capacitor and the second capacitor.

5. The wireless power receiver of claim 1, wherein the plurality of inductive elements is arranged to perform low-Q inductive charging in a low frequency range including the first resonant frequency.

6. The wireless power receiver of claim 1, wherein the plurality of inductive elements is arranged to perform high-Q resonant charging in a high frequency range including the second resonant frequency.

7. The wireless power receiver of claim 1, further comprising the rectifier, wherein the rectifier comprises a synchronous rectifier or a bridge rectifier.

8. The wireless power receiver of claim 1, wherein an effective inductance of the electromagnetic resonator is lower at the second resonant frequency than at the first resonant frequency.

9. The wireless power receiver of claim 1, wherein the plurality of inductive elements is fabricated in the same plane of a printed circuit board.

10. The wireless power receiver of claim 1, wherein the plurality of inductive elements comprises first and second inductive elements, wherein the first inductive element surrounds the second inductive element.

11. The wireless power receiver of claim 1, wherein the first resonant frequency is lower than the second resonant frequency by a factor of at least five.

12. The wireless power receiver of claim 1, wherein the second resonant frequency is within the ISM band.

13. The wireless power receiver of claim 1, wherein the first resonant frequency is between 100 kHz and 200 kHz and the second resonant frequency is 6.78 MHz.

14. The wireless power receiver of claim 1, wherein the plurality of inductive elements further comprises a second inductive element, and the first capacitor has a terminal coupled between the first inductive element and the second inductive element.

15. The wireless power receiver of claim 1, wherein the plurality of inductive elements further comprises a second inductive element concentric with the first inductive element.

16. The wireless power receiver of claim 1, further comprising:

a plurality of switching elements coupled to the network of passive components to convert from AC to DC.

17. The wireless power receiver of claim 1, wherein the wireless power receiver is a multi-mode wireless power receiver configured to receive power wirelessly at the first resonant frequency or the second resonant frequency.

18. The wireless power receiver of claim 1, wherein the wireless power receiver is configured to provide in-band communications based on load modulation.