Method for performing wireless charging control of an electronic device with aid of predetermined data in non-volatile memory, and associated apparatus

• US 9,941,751 B2
• Filed: 04/01/2014
• Issued: 04/10/2018
• Est. Priority Date: 01/27/2014
• Status: Active Grant

• Current Assignee: MediaTek, Inc.
• Original Assignee: MediaTek, Inc.
• Inventors: Juan, Kuan-Kai, Tsai, Li-Ting
• Primary Examiner(s): NGUYEN, NHA T
• Application Number:
  US14/242,858
• Publication Number:
  US 20150214773A1
• Time in Patent Office: 1,470 Days
• CPC Class Codes: H02J 50/00 Circuit arrangements or systems for wireless supply or distribution of electric power
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/60 responsive to the presence of foreign objects, e.g. detection of living beings
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge

Abstract

A method for performing wireless charging control of an electronic device and an associated apparatus are provided, where the method includes: performing at least one detection operation at a direct current (DC) output terminal of a rectifier of the electronic device to generate at least one detection result, wherein two alternating current (AC) input terminals of the rectifier are coupled to two terminals of a power input coil of the electronic device, and the at least one detection operation is not performed at the power input coil; and estimating input power of the power input coil according to the at least one detection result with aid of a set of predetermined data, and sending a packet carrying information corresponding to the estimated input power, for performing wireless charging foreign object detection (FOD), wherein the set of predetermined data is stored in a non-volatile (NV) memory of the electronic device.

Claims

1. A method for performing wireless charging control of an electronic device, the method comprising the steps of:

receiving at least one detection result, the detection result indicating a result of a detection operation at a DC output terminal of a rectifier of the electronic device, wherein the rectifier is coupled to a power input coil, wherein the at least one detection result indicates a current that is output through a DC output terminal of the rectifier; and

estimating, by the electronic device, an input power of the power input coil, the input power being estimated using the at least one detection result and a set of predetermined data, the set of predetermined data comprising a first estimated input power level for a first current level of the DC output terminal and a second estimated input power level for a second current level of the DC output terminal, wherein the set of predetermined data is stored in a non-volatile (NV) memory of the electronic device as look up table,

wherein information regarding the estimated input power is transmitted to a transmitter for the transmitter to perform wireless charging foreign object detection (FOD) using the information regarding the estimated input power.

2. The method of claim 1, wherein the rectifier obtains an AC input from the power input coil, and rectifies the AC input to provide a DC output at the DC output terminal.

3. The method of claim 2, wherein the AC input is obtained from the power input coil when the electronic device is wirelessly charged through the power input coil.

4. The method of claim 1, further comprising the step of performing at least one detection operation at the DC output terminal of the rectifier of the electronic device to generate the at least one detection result, the step comprising:

detecting at least one voltage difference between two terminals of a current sensing resistor, wherein one of the two terminals of the current sensing resistor is coupled to the DC output terminal of the rectifier, and another of the two terminals of the current sensing resistor is coupled to a DC input terminal of a next stage of the rectifier; and

converting the at least one voltage difference into the at least one detection result.

5. The method of claim 1, wherein the step of estimating the input power of the power input coil comprises:

estimating the input power of the power input coil using a function obtained from curve fitting of at least one portion of the set of predetermined data.

6. The method of claim 1, wherein the at least one detection operation is performed in a DC power region of the electronic device, and the input power of the power input coil belongs to an AC power region of the electronic device.

7. The method of claim 1, wherein the at least one detection operation is not performed at the power input coil.

8. The method of claim 1, wherein the transmitting comprises sending a packet carrying the information regarding the estimated input power.

9. The method of claim 1, wherein the set of predetermined data is obtained using a calibration procedure.

10. An apparatus for performing wireless charging control of an electronic device, the apparatus comprising at least one portion of the electronic device, the apparatus comprising:

a controller, arranged to receive at least one detection result, wherein the at least one detection result indicates a current that is output through a DC output terminal of a rectifier of the electronic device, the controller being arranged to receive a set of predetermined data representing at least first and second estimated input power levels as a function of current levels of a DC output terminal of the rectifier, the controller being arranged to estimate input power of a power input coil coupled to the rectifier, the input power being estimated using the at least one detection result and the set of predetermined data, and arranged to transmit information regarding the estimated input power to a transmitter for the transmitter to perform wireless charging foreign object detection (FOD), wherein the set of predetermined data is stored in a non-volatile (NV) memory of the electronic device as look up table.

11. The apparatus of claim 10, wherein the apparatus comprises the rectifier;

the rectifier obtains an AC input from the power input coil, and rectifies the AC input to provide a DC output at the DC output terminal.

12. The apparatus of claim 11, wherein the AC input is obtained from the power input coil when the electronic device is wirelessly charged through the power input coil.

13. The apparatus of claim 10, further comprising a detection module, wherein the detection module comprises:

a current sensing resistor, wherein one of two terminals of the current sensing resistor is coupled to the DC output terminal of the rectifier, and another of the two terminals of the current sensing resistor is coupled to a DC input terminal of a next stage of the rectifier;

wherein the apparatus comprises;

an analog-to-digital converter (ADC), coupled to the current sensing resistor, arranged to perform analog-to-digital conversion on a detection signal of the detection module, in order to generate a digital signal, wherein the digital signal carries the at least one detection result;

wherein the detection module detects at least one voltage difference between the two terminals of the current sensing resistor, and utilizes the ADC to convert the at least one voltage difference into the at least one detection result; and

the detection signal of the detection module carries the at least one voltage difference.

14. The apparatus of claim 10, wherein the controller estimates the input power of the power input coil using a function obtained from curve fitting of at least one portion of the set of predetermined data.

15. The apparatus of claim 10, wherein the at least one detection operation is performed in a DC power region of the electronic device, and the input power of the power input coil belongs to an AC power region of the electronic device.

16. The apparatus of claim 10, wherein the at least one detection operation is not performed at the power input coil.

17. The apparatus of claim 10, wherein the controller is configured to send a packet carrying the information regarding the estimated input power.

18. The apparatus of claim 10, wherein the set of predetermined data is obtained using a calibration procedure.

19. An apparatus for performing wireless charging control of an electronic device, the apparatus comprising at least one portion of the electronic device, the apparatus comprising:

a controller, arranged to receive at least one detection result, wherein the at least one detection result indicates a current that is output through a DC output terminal of a rectifier of the electronic device, the controller being arranged to receive a set of predetermined data representing at least first and second estimated input power levels as a function of current levels of a DC output terminal of the rectifier, arranged to estimate input power of a power input coil coupled to the rectifier, the input power being estimated using the at least one detection result and a set of predetermined data comprising a first estimated input power level for a first current level of the DC output terminal and a second estimated input power level for a second current level of the DC output terminal, wherein the set of predetermined data is stored in a non-volatile (NV) memory of the electronic device as look up table.

20. The apparatus of claim 19, wherein the first estimated input power is higher than the second estimated input power and the first current level is higher than the second current level.

21. The apparatus of claim 19, wherein the apparatus is configured to transmit information regarding the estimated input power to a transmitter to perform wireless charging foreign object detection (FOD).