Charging system, charging method, and device

Patent metadata

Field	Value
Publication number	US-10644530-B2
Application number	US-201716063268-A
Country	US
Kind code	B2
Filing date	Jan 7, 2017
Priority date	Feb 5, 2016
Publication date	May 5, 2020
Grant date	May 5, 2020

Abstract

Provided are a charging system, charging method, and device, said charging system comprising a battery; a first rectifier, configured to output a first voltage with a first pulsating waveform; a switch unit, configured to modulate the first voltage; a transformer, configured to output a second voltage with a second pulsating waveform; a second rectifier, configured to output a third voltage with a third pulsating waveform, and the third voltage is configured to be applied to the battery charge the battery; a first current sampling circuit, configured to sample current to obtain a current sampling value; and a control unit configured to output the control signal to the switch unit, adjust the amplification factor of the operational amplifier, and adjust a duty ratio of the control signal according to the current sampling value, such that the third voltage meets a charging requirement of the battery.

First claim

What is claimed is:

1. A charging system:
a battery;
a first rectifier, configured to rectify an input alternating current and output a first voltage with a first pulsating waveform;
a switch unit, configured to modulate the first voltage according to a control signal;
a transformer, configured to output a second voltage with a second pulsating waveform according to the modulated first voltage;
a second rectifier, configured to rectify the second voltage to output a third voltage with a third pulsating waveform, and the third voltage is configured to be applied to the battery to charge the battery;
a first current sampling circuit, configured to sample a current outputted by the second rectifier to obtain a current sampling value, wherein the first current sampling circuit comprises an operational amplifier with an adjustable amplification factor; and
a control unit, coupled to the first current sampling circuit and the switch unit respectively, and configured to output the control signal to the switch unit, to adjust the amplification factor of the operational amplifier according to a charging mode, and to adjust a duty ratio of the control signal according to the current sampling value, such that the third voltage meets a charging requirement of the battery.

2. A device, comprising:
a first rectifier, configured to rectify an input alternating current and output a first voltage with a first pulsating waveform;
a switch unit, configured to modulate the first voltage according to a control signal;
a transformer, configured to output a second voltage with a second pulsating waveform according to the modulated first voltage;
a second rectifier, configured to rectify the second voltage to output a third voltage with a third pulsating waveform, and the third voltage being configured to be applied to a battery in a terminal to charge the battery in the terminal when the device is coupled to the terminal;
a first current sampling circuit, configured to sample a current outputted by the second rectifier to obtain a current sampling value, wherein the first current sampling circuit comprises an operational amplifier with an adjustable amplification factor; and
a control unit, coupled to the first current sampling circuit and the switch unit respectively, and configured to output the control signal to the switch unit, to adjust the amplification factor of the operational amplifier according to a charging mode, and to adjust a duty ratio of the control signal according to the current sampling value, such that the third voltage meets a charging requirement when the device is coupled to the terminal.

3. The device according to claim 2 , wherein, the device comprises a first charging interface,
the first charging interface comprises: a power wire, configured to charge the battery; and a data wire, configured to communicate with the terminal when the device is coupled to the terminal via the first charging interface;
the control unit is configured to communicate with the terminal via the first charging interface to determine the charging mode, in which the charging mode comprises a first charging mode and a second charging mode.

4. The device according to claim 3 , wherein the control unit is further configured to:
decrease the amplification factor of the operational amplifier when determining to charge the terminal in the first charging mode by performing a bidirectional communication with the terminal via the data wire of the first charging interface, so as to prevent saturation of the operational amplifier; and
increase the amplification factor of the operational amplifier when determining to charge the terminal in the second charging mode by performing the bidirectional communication with the terminal via the data wire of the first charging interface, so as to increase a current detection precision of the first current sampling circuit.

5. The device according to claim 2 , wherein,
the first current sampling circuit further comprises:
a first resistor, comprising: an end coupled to an output end of the second rectifier;
a second resistor, comprising: an end coupled to the end of the first resistor and the output end of the second rectifier respectively; and the other end coupled to a first input end of the operational amplifier; wherein the other end of the second resistor is further grounded via a first filtering capacitor; and
a third resistor, comprising: an end coupled to the other end of the first resistor; and the other end coupled to a second input end of the operational amplifier; wherein the other end of the third resistor is further grounded via a second filtering capacitor;

wherein an adjusting end of the operational amplifier is coupled to the control unit.

6. The device according to claim 3 , wherein when determining to charge the terminal in the first charging mode by performing the bidirectional communication with the terminal via the data wire of the first charging interface,
the control unit is configured to send a first instruction to the terminal, in which the first instruction is configured to query the terminal whether to operate in the first charging mode; and
the control unit is configured to receive a reply instruction of the first instruction from the terminal, in which the reply instruction of the first instruction is configured to indicate that the terminal agrees to operate in the first charging mode.

7. The device according to claim 6 , wherein, before the control unit sends the first instruction to the terminal, the device is configured to charge the terminal in the second charging mode, and the control unit is configured to send the first instruction to the terminal when determining that a charging duration in the second charging mode is greater than a predetermined threshold.

8. The device according to claim 6 , wherein the control unit is further configured to control the device to adjust a charging current to a charging current in the first charging mode by controlling the switch unit, and before the device charges the terminal with the charging current in the first charging mode, the control unit is configured to perform the bidirectional communication with the terminal via the data wire of the first charging interface to determine a charging voltage in the first charging mode, and to control the device to adjust a charging voltage to the charging voltage in the first charging mode.

9. The device according to claim 8 , wherein when performing the bidirectional communication with the terminal via the data wire of the first charging interface to determine the charging voltage in the first charging mode,
the control unit is configured to send a second instruction to the terminal, in which the second instruction is configured to query whether a current output voltage of the device is suitable as the charging voltage in the first charging mode;
the control unit is configured to receive a reply instruction of the second instruction sent from the terminal, in which the reply instruction of the second instruction is configured to indicate that the current output voltage of the device is suitable, high or low; and
the control unit is configured to determine the charging voltage in the first charging mode according to the reply instruction of the second instruction.

10. The device according to claim 8 , the control unit is further configured to perform the bidirectional communication with the terminal via the data wire of the first charging interface to determine the charging current in the first charging mode.

11. The device according to claim 10 , wherein, when performing the bidirectional communication with the terminal via the data wire of the first

Assignees

• Guangdong Oppo Mobile Telecommunications Corp Ltd

Inventors

• Tian Chen
• Zhang Jialiang

Classifications

• H02M3/335

  using semiconductor devices only · CPC title

• H02M5/04

  by static converters (controlling transformers, reactors or choke coils, e.g. by tap changing H02P13/00) · CPC title

• H02M3/33507

  with automatic control of the output voltage or current, e.g. flyback converters (H02M3/33561, H02M3/33569 take precedence) · CPC title

• H02M7/217

  using semiconductor devices only · CPC title

• H02M1/44

  Circuits or arrangements for compensating for electromagnetic interference in converters or inverters · CPC title