Apparatus, system, and method for back-channel communication in an inductive wireless power transfer system

• US 8,942,624 B2
• Filed: 03/30/2012
• Issued: 01/27/2015
• Est. Priority Date: 03/30/2012
• Status: Active Grant

• Current Assignee: Integrated Device Technology Incorporated (Renesas Electronics Corporation)
• Original Assignee: Integrated Device Technology Incorporated (Renesas Electronics Corporation)
• Inventors: Singh, Manjit, Bastami, Siamak, Wilson, David
• Primary Examiner(s): VO, NGUYEN THANH
• Application Number:
  US13/436,135
• Publication Number:
  US 20130260676A1
• Time in Patent Office: 1,033 Days
• Field of Search: 455/41.1, 455/41.2, 307/104, 307/154, 320/108
• US Class Current: 455/41.1
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/20 using microwaves or radio frequency waves
• CPC Class Codes: H02J 50/60 responsive to the presence of foreign objects, e.g. detection of living beings
• CPC Class Codes: H04B 5/26 using coils
• CPC Class Codes: H04B 5/45 Transponders
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

An inductive wireless power transfer device comprises a transmitter that comprises a transmit coil configured to generate a wireless power signal to a coupling region in response to an input voltage, and a modulator configured to modulate the wireless power signal and encode data with the wireless power signal to establish a back-channel communication link from the transmitter to a receiver. An inductive wireless power receiving device comprises a receiver that comprises a receive coil configured to generate a time varying signal in response to receiving a modulated wireless power signal from a transmitter in a coupling region, and a demodulator configured to demodulate the modulated wireless power signal from an established back-channel communication link from the transmitter to a receiver. Related inductive wireless power transfer systems and methods for back-channel communication from the transmitter to the receiver of an inductive wireless power transfer system are disclosed.

Claims

1. An inductive wireless power transfer device, comprising:

a transmitter, comprising;

a transmit coil configured to generate a wireless power signal to a coupling region in response to an input voltage;

a modulator configured to modulate the wireless power signal and encode data with the wireless power signal to establish a back-channel communication link from the transmitter to a receiver, and is configured to increase the control characteristic from a baseline level to be a logic ‘

1’

bit, and decrease the control of the control characteristic from the baseline level to be a logic ‘

0’

bit; and

an inverter configured to generate a time varying current through the transmit coil having a frequency for the wireless power signal, and wherein the inverter includes a switch network controlled by a processor according to a switching frequency, wherein the modulator is configured to adjust a control characteristic of the inverter to modulate the wireless power signal.

2. The inductive wireless power transfer device of claim 1, wherein the control characteristic a switching frequency of the switch network.