Smart wireless charger

• US 9,647,482 B2
• Filed: 08/22/2014
• Issued: 05/09/2017
• Est. Priority Date: 08/22/2014
• Status: Active Grant

• Current Assignee: NXP B.V. (NXP Semiconductors NV)
• Original Assignee: NXP B.V. (NXP Semiconductors NV)
• Inventors: Rudolph, Thomas Klaus
• Primary Examiner(s): Whitmore, Stacy
• Application Number:
  US14/466,030
• Publication Number:
  US 20160056658A1
• Time in Patent Office: 991 Days
• Field of Search: 320107-108, 320114
• CPC Class Codes: G01R 29/0814 Field measurements related to measuring influence on or from apparatus, components or humans EMC, EMI and similar testing in general G01R31/001, e.g. in ESD, EMI, EMC, EMP testing, measuring radiation leakage; detecting presence of micro- or radiowave emitters; dosimetry; testing shielding; measurements related to lightning
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
• CPC Class Codes: H04B 5/24 Inductive coupling
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

A wireless charging system is disclosed. The wireless charging system includes a coil to create electromagnetic field and a sniffer system to detect a presence of a low frequency (LF) signal. The sniffer system is configured to deactivate the coil for a predetermined duration and perform an operation to detect the presence of the LF signal.

Claims

1. A wireless charging system, comprising:

an induction coil configured to create an electromagnetic field; and

a sniffer system configured to detect communication by a low frequency (LF) signal at preselected intervals between a base station and a wireless key, deactivate the induction coil prior to performing the detection of communication by the LF signal, and continue to keep the induction coil deactivated for a predetermined duration after the sniffer system detected the communication by the LF signal between the base station and the key.

2. The wireless charging system of claim 1, wherein the sniffer system includes a LF sensing coil and a signal detector.

3. The wireless charging system of claim 1, wherein the LF signal is transmitted by a keyless entry system.

4. The wireless charging system of claim 1, wherein the induction coil is configured to transmit electromagnetic energy to charge a battery of an external device.

5. A method, comprising:

(a) deactivating an induction coil in a wireless charging system;

(b) activating a low frequency (LF) detection system incorporated in the wireless charging system; and

(c) detecting, in the wireless charging system, communication by a LF signal between the base station and a wireless key, wherein, if the LF signal is detected, continuing to keep the induction coil deactivated for a predetermined duration and, if the LF signal is not detected, reactivating the induction coil.

6. The method of claim 5, further comprising:

repeating steps (a) to (c) at regular predetermined intervals.