Power supply device of induction type power supply system and NFC device identification method of the same

• US 10,615,645 B2
• Filed: 09/07/2018
• Issued: 04/07/2020
• Est. Priority Date: 02/01/2011
• Status: Active Grant

• Current Assignee: Fu Da Tong Technology Co., Ltd.
• Original Assignee: Fu Da Tong Technology Co., Ltd.
• Inventors: Tsai, Ming-Chiu, Chan, Chi-Che
• Primary Examiner(s): Elamin, Abdelmoniem I
• Application Number:
  US16/124,211
• Publication Number:
  US 20190020222A1
• Time in Patent Office: 578 Days
• CPC Class Codes: G05B 9/02 electric
• CPC Class Codes: G05F 1/66 Regulating electric power
• CPC Class Codes: H02J 50/12 of the resonant type
• 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: H04B 5/24 Inductive coupling

Abstract

A power supply device used in an induction type power supply system is provided that includes a power supply coil, a auxiliary coil, a power supply driving module, a detection driving module, a signal detection module and a processing module. The power supply driving module drives the power supply coil to transmit a power signal. When the power supply driving module is under a non-working status, the detection driving module drives the auxiliary coil to transmit a detection signal and drives the auxiliary coil to transmit a data request signal. After transmitting the data request signal, the signal detection module detects a reflection signal corresponding to the data request signal on the auxiliary coil. The processing module keeps the power supply driving module under the non-working status when the reflection signal having a data characteristic is determined to be detected by the signal detection module.

Claims

1. A power supply device used in an induction type power supply system, wherein the power supply device comprises:

a power supply coil;

an auxiliary coil;

a power supply driving module electrically coupled to the power supply coil and configured to drive the power supply coil to transmit a power signal;

an auxiliary driving module electrically coupled to the auxiliary coil and configured to drive the auxiliary coil to transmit a detection signal during a first time interval and drive the auxiliary coil to transmit a data request signal during a second time interval after the first time interval when the power supply driving module is under a non-working status;

a signal detection module electrically coupled to the auxiliary coil and configured to detect a reflection signal corresponding to the data request signal on the auxiliary coil during a third time interval after the second time interval that the data request signal is transmitted; and

a processing module configured to determine whether the signal detection module detects the reflection signal having a data characteristic and further keep the power supply driving module under the non-working status when the reflection signal having the data characteristic is determined to be detected by the signal detection module.

2. The power supply device of claim 1, wherein the processing module determines that a smart card exists within a power supplying range of the power supply coil when the reflection signal having the data characteristic is determined to be detected by the signal detection module.

3. The power supply device of claim 1, wherein the processing module does not decode the reflection signal.

4. The power supply device of claim 1, wherein the signal detection module comprises:

a digital to analog converter configured to generate a reference voltage; and

a comparator electrically coupled to the digital to analog converter and the auxiliary coil and configured to receive the reference voltage and a detected voltage related to the auxiliary coil to detect the reflection signal.

5. The power supply device of claim 4, wherein the comparator is configured to control the digital to analog converter to use the reference voltage to track and lock a peak voltage by using a feedback mechanism according to a first comparison result of the detected voltage and the reference voltage during the first time interval, and the digital to analog converter fine-tunes the reference voltage during the third time interval by using a pitch value such that the comparator detects the reflection signal according to a second comparison result of the detected voltage and the fine-tuned reference voltage.

6. The power supply device of claim 5, wherein the digital to analog converter increases the reference voltage with the pitch value during the third time interval such that the reflection signal is determined to have the data characteristic when the second comparison result comprises a part showing that the detected voltage is larger than the fine-tuned reference voltage and the reflection signal is determined to not have the data characteristic when the second comparison result does not comprise the part showing that the detected voltage is larger than the fine-tuned reference voltage.

7. The power supply device of claim 5, wherein the digital to analog converter decreases the reference voltage with the pitch value during the third time interval such that the reflection signal is determined to have the data characteristic when the second comparison result comprises a part showing that the detected voltage is smaller than the fine-tuned reference voltage and the reflection signal is determined to not have the data characteristic when the second comparison result does not comprise the part showing that the detected voltage is smaller than the fine-tuned reference voltage.

8. The power supply device of claim 4, further comprising a voltage-dividing module electrically coupled between the auxiliary coil and the comparator, and the detected voltage received by the comparator is a divided voltage of a voltage on the auxiliary coil.

9. The power supply device of claim 1, wherein the auxiliary driving module stops and starts to drive the auxiliary coil in an interlaced manner for several times to generate the data request signal.

10. The power supply device of claim 1, wherein the processing module keeps the power supply driving module under a working status to drive the power supply coil to transmit the power signal when the reflection signal not having the data characteristic is determined to be detected by the signal detection module.

11. A near field communication (NFC) device identifying method used in a power supply device in an induction type power supply system, wherein the NFC device identifying method comprises:

driving an auxiliary coil to transmit a detection signal during a first time interval and driving the auxiliary coil to transmit a data request signal during a second time interval after the second time interval when a power supply driving module is under a non-working status by an auxiliary driving module electrically coupled to the auxiliary coil;

detecting a reflection signal corresponding to the data request signal on the auxiliary coil during a third time interval after the second time interval that the data request signal is transmitted by a signal detection module;

determining whether the signal detection module detects the reflection signal having a data characteristic by a processing module; and

keeping the power supply driving module under the non-working status by the processing module when the reflection signal having the data characteristic is determined to be detected by the signal detection module.

12. The NFC device identifying method of claim 11, further comprising:

determining that a smart card exists within a power supplying range of the power supply coil by the processing module when the reflection signal having the data characteristic is determined to be detected by the signal detection module.

13. The NFC device identifying method of claim 11, further comprising:

not decoding the reflection signal by the processing module.

14. The NFC device identifying method of claim 11, further comprising:

generating a reference voltage by a digital to analog converter of the signal detection module; and

receiving the reference voltage and a detected voltage related to the auxiliary coil to detect the reflection signal by a comparator of the signal detection module.

15. The NFC device identifying method of claim 14, further comprising:

controlling the digital to analog converter to use the reference voltage to track and lock a peak voltage by using a feedback mechanism according to a first comparison result of the detected voltage and the reference voltage during the first time interval by the comparator; and

fine-tuning the reference voltage during the third time interval by using a pitch value by the digital to analog converter such that the comparator detects the reflection signal according to a second comparison result of the detected voltage and the fine-tuned reference voltage.

16. The NFC device identifying method of claim 15, wherein the digital to analog converter increases the reference voltage with the pitch value during the third time interval such that the reflection signal is determined to have the data characteristic when the second comparison result comprises a part showing that the detected voltage is larger than the fine-tuned reference voltage and the reflection signal is determined to not have the data characteristic when the second comparison result does not comprise the part showing that the detected voltage is larger than the fine-tuned reference voltage.

17. The NFC device identifying method of claim 15, wherein the digital to analog converter decreases the reference voltage with the pitch value during the third time interval such that the reflection signal is determined to have the data characteristic when the second comparison result comprises a part showing that the detected voltage is smaller than the fine-tuned reference voltage and the reflection signal is determined to not have the data characteristic when the second comparison result does not comprise the part showing that the detected voltage is smaller than the fine-tuned reference voltage.

18. The NFC device identifying method of claim 14, further comprising:

receiving a divided voltage of a voltage on the auxiliary coil as the detected voltage by the comparator.

19. The NFC device identifying method of claim 11, further comprising:

stopping and starting to drive the auxiliary coil in an interlaced manner for several times to generate the data request signal by the auxiliary driving module.

20. The NFC device identifying method of claim 11, further comprising:

keeping the power supply driving module under a working status to drive the power supply coil to transmit the power signal by the processing module when the reflection signal not having the data characteristic is determined to be detected by the signal detection module.