Charging system, lightning protection method for terminal during charging, and power adapter

Patent metadata

Field	Value
Publication number	US-10348121-B2
Application number	US-201715649507-A
Country	US
Kind code	B2
Filing date	Jul 13, 2017
Priority date	Feb 5, 2016
Publication date	Jul 9, 2019
Grant date	Jul 9, 2019

Abstract

The present disclosure discloses a charging system, a lightning protection method for a terminal during charging and a power adapter. The charging system includes a power adapter and a terminal. The power adapter includes a first rectifier, a switch unit, a transformer, a second rectifier, a first charging interface, a second voltage sampling circuit, and a control unit. The control unit adjusts a duty ratio of a control signal such that a third voltage with a third ripple waveform outputted by the second rectifier meets a charging requirement, and controls the switch unit to switch on for a first predetermined time period for discharging when the voltage value sampled is greater than a first predetermined voltage value. The terminal includes a second charging interface and a battery. When the second charging interface is coupled to the first charging interface, the second charging interface applies the third voltage to the battery.

First claim

What is claimed is:

1. A power adapter, comprising:
a first rectifier, configured to rectify an input alternating current and output a first voltage with a first ripple waveform;
a switch unit, configured to modulate the first voltage according to a control signal and output a modulated first voltage;
a transformer, configured to output a second voltage with a second ripple waveform according to the modulated first voltage;
a second rectifier, configured to rectify the second voltage to output a third voltage with a third ripple waveform;
a first charging interface, coupled to the second rectifier, configured to apply the third voltage to a battery in a terminal via a second charging interface of the terminal when the first charging interface is coupled to the second charging interface, in which the second charging interface is coupled to the battery;
a voltage sampling circuit, configured to sample the first voltage with the first ripple waveform; and
a control unit, coupled to the voltage sampling circuit and the switch unit respectively, and configured to output the control signal to the switch unit, to adjust a duty ratio of the control signal such that the third voltage meets a charging requirement of the terminal, and to control the switch unit to switch on for a first predetermined time period for discharging when a voltage value sampled by the voltage sampling circuit is greater than a first predetermined voltage value.

2. The power adapter according to claim 1 , wherein the control unit is coupled to the first charging interface, and is further configured to communicate with the terminal via the first charging interface so as to obtain status information of the terminal.

3. The power adapter according to claim 1 , wherein the control unit is further configured to adjust the duty ratio of the control signal according to the status information of the terminal.

4. The power adapter according to claim 1 , wherein a waveform of the modulated first voltage keeps synchronous with the third ripple waveform.

5. The power adapter according to claim 4 , wherein the first charging interface comprises:
a power wire, configured to charge the battery; and
a data wire, configured to communicate with the terminal;
wherein the control unit is configured to communicate with the terminal via the first charging interface to determine a charging mode, in which the charging mode comprises a second charging mode and a first charging mode.

6. The power adapter according to claim 5 , wherein the control unit is further configured to obtain a charging current and/or a charging voltage corresponding to the second charging mode according to the status information of the terminal and to adjust the duty ratio of the control signal according to the charging current and/or the charging voltage corresponding to the second charging mode, when determining the charging mode as the second charging mode.

7. The power adapter according to claim 5 , wherein the status information of the terminal comprises a temperature of the battery, wherein when the temperature of the battery is greater than a first predetermined temperature threshold or the temperature of the battery is less than a second predetermined temperature threshold, the second charging mode is switched to the first charging mode when a current charging mode is the second charging mode, in which the first predetermined temperature threshold is greater than the second predetermined temperature threshold.

8. The power adapter according to claim 7 , wherein the control unit is further configured to control the switch unit to switch off when the temperature of the battery is greater than a predetermined high temperature protection threshold.

9. The power adapter according to claim 2 , wherein the status information of the terminal comprises an electric quantity of the battery, a temperature of the battery, a voltage/current of the terminal, interface information of the terminal and information on a path impedance of the terminal.

10. The power adapter according to claim 9 , wherein, the control unit is further configured to obtain a temperature of the first charging interface, and to control the switch unit to switch off when the temperature of the first charging interface is greater than a predetermined protection temperature.

11. The power adapter according to claim 1 , wherein the control unit is further configured to output the control signal to the switch unit to control the switch unit to switch on or off when the voltage value sampled by the voltage sampling circuit is less than or equal to a third predetermined voltage value, in which the third predetermined voltage value is less than the first predetermined voltage value.

12. A charging system, comprising:
a power adapter, comprising:
a first rectifier, configured to rectify an input alternating current and output a first voltage with a first ripple waveform;
a switch unit, configured to modulate the first voltage according to a control signal and output a modulated first voltage;
a transformer, configured to output a second voltage with a second ripple waveform according to the modulated first voltage;
a second rectifier, configured to rectify the second voltage to output a third voltage with a third ripple waveform;

a first charging interface, coupled to the second rectifier;
a voltage sampling circuit, configured to sample the first voltage with the first ripple waveform; and
a control unit, coupled to the voltage sampling circuit and the switch unit respectively, and configured to output the control signal to the switch unit, to adjust a duty ratio of the control signal such that the third voltage meets a charging requirement, and to control the switch unit to switch on for a first predetermined time period for discharging when a voltage value sampled by the voltage sampling circuit is greater than a first predetermined voltage value,
and

a terminal, comprising a second charging interface and a battery, the second charging interface being coupled to the battery, wherein the second charging interface is configured to apply the third voltage to the battery when the second charging interface is coupled to the first charging interface.

13. The charging system according to claim 12 , wherein the control unit is coupled to the first charging interface, and is further configured to communicate with the terminal via the first charging interface so as to obtain status information of the terminal.

14. The charging system according to claim 12 , wherein a waveform of the modulated first voltage keeps synchronous with the third ripple waveform.

15. The charging system according to claim 13 , wherein the first charging interface comprises:
a power wire, configured to charge the battery; and
a data wire, configured to communicate with the terminal;
wherein the control unit is configured to communicate with the terminal via the first charging interface so as to determine a charging mode, in which the charging mode comprises a second charging mode and a first charging mode.

16. The charging system according to claim 15 , wherein the control unit is further configured to obtain a charging current and/or a charging voltage corresponding to the second charging mode according to the status information of the terminal and to adjust the duty ratio of the control signal according to the charging current and/or the charging voltage corresponding to the second charging mode, when determining the charging mode as the second charging mode.

17. The charging system according to claim 15 , wherei

Assignees

• Guangdong Oppo Mobile Telecommunications Corp Ltd

Inventors

• Zhang Jialiang
• Chen Shebiao
• Zhang Jun
• Tian Chen
• Wan Shiming
• Li Jiada

Classifications

• H02J7/825

  Detection of fully charged condition · CPC title

• H02J7/94

  in response to battery current · CPC title

• H02J7/82

  Control of state of charge [SOC] · CPC title

• H02J7/42

  with electronic devices having internal batteries, e.g. mobile phones · CPC title

• H02J7/975

  in response to temperature · CPC title