Adapter and charging control method

Patent metadata

Field	Value
Publication number	US-10566828-B2
Application number	US-201715570519-A
Country	US
Kind code	B2
Filing date	Jan 7, 2017
Priority date	Feb 5, 2016
Publication date	Feb 18, 2020
Grant date	Feb 18, 2020

Abstract

An adapter, a charging control method and a charging system are provided. The adapter includes: a power converter, configured to convert input alternating current to obtain an output voltage and an output current of the adapter, the output current of the adapter being a current with a first pulsating waveform; a sampling and holding unit, coupled to the power converter, and configured to sample the current with the first pulsating waveform in a sampling state, and to hold a peak value of the current in a holding state; a current sampling controller, coupled to the sampling and holding unit, and configured to determine whether the sampling and holding unit is in the holding state, and to sample the peak value of the current with the first pulsating waveform held by the sampling and holding unit when the sampling and holding unit is in the holding unit.

First claim

What is claimed is:

1. An adapter, supporting a first charging mode and a second charging mode, the first charging mode being a constant voltage mode, the second charging mode being a constant current mode; in the second charging mode, an output voltage of the adapter being directly applied to both ends of a battery of a device to be charged and an output current of the adapter being made to directly pass through the battery for direct charging of the battery, and the adapter comprising:
a power converter, configured to convert input alternating current to obtain the output voltage and the output current of the adapter, wherein the output current of the adapter is a current with a first pulsating waveform;
a sampling and holding unit, coupled to the power converter, and configured to sample the current with the first pulsating waveform in a sampling state, and to hold a peak value of the current with the first pulsating waveform in a holding state;
a current sampling controller, coupled to the sampling and holding unit, and configured to determine whether the sampling and holding unit is in the holding state, and to sample the peak value of the current with the first pulsating waveform held by the sampling and holding unit when the sampling and holding unit is in the holding state.

2. The adapter according to claim 1 , wherein the current sampling controller is configured to receive a synchronous signal, and to determine whether the sampling and holding unit is in the holding state based on the synchronous signal, in which a cycle of the synchronous signal is 1/N of a cycle of the first pulsating waveform, N is an integer greater than or equal to 1.

3. The adapter according to claim 2 , wherein the current sampling controller is configured to obtain the synchronous signal from the sampling and holding unit, wherein the sampling and holding unit is configured to sample the current with the first pulsating waveform to obtain a sampling current, to convert the sampling current to a sampling voltage, and to send the sampling voltage to the current sampling controller as the synchronous signal, in which the sampling voltage is configured to indicate a magnitude of the current with the first pulsating waveform.

4. The adapter according to claim 2 , wherein the current sampling controller is configured to determine whether the first pulsating waveform is at the peak value or in a falling edge based on the synchronous signal, and to sample the peak value of the current with the first pulsating waveform held by the sampling and holding unit when determining that the first pulsating waveform is at the peak value or in the falling edge.

5. The adapter according to claim 4 , wherein the current sampling controller comprises:
a comparator, wherein a first input end of the comparator is configured to receive the synchronous signal, and a second input end of the comparator is configured to receive a reference voltage; and
a control unit, coupled to an output end of the comparator, and configured to determine whether the first pulsating waveform is at the peak value or in the falling edge based on a comparison result between a voltage of the synchronous signal and the reference voltage.

6. The adapter according to claim 4 , wherein the current sampling controller comprises:
a comparing unit, comprising a capacitor and a comparator, in which the capacitor is configured to receive the synchronous signal and to filter out a direct current signal in the synchronous signal to obtain an alternating current signal at zero crossing point, a first input end of the comparator is coupled to the capacitor and configured to receive the alternating current signal, a second input end of the comparator is configured to receive a reference voltage, and the comparator is configured to compare a voltage of the alternating current signal with the reference voltage; and
a control unit, coupled to an output end of the comparator, and configured to determine whether the first pulsating waveform is at the peak value or in the falling edge based on a comparison result between the voltage of the synchronous signal and the reference voltage, in which a voltage value of the reference voltage is zero.

7. The adapter according to claim 2 , wherein the cycle of the first pulsating waveform is same with the cycle of the synchronous signal.

8. The adapter according to claim 1 , wherein the current sampling controller is further configured to control the sampling and holding unit to switch to the sampling state from the holding state after the peak value of the current with the first pulsating waveform is sampled by the current sampling controller.

9. The adapter according to claim 8 , wherein the sampling and holding unit comprises a capacitor, and the sampling and holding unit is configured to hold the peak value of the current with the first pulsating waveform based on the capacitor in the sampling and holding unit;
the current sampling controller comprises a discharging unit and a control unit, the discharging unit is coupled to the control unit and the capacitor in the sampling and holding unit respectively, and configured to the release charges in the capacitor of the sampling and holding unit under a control of the control unit, such that the sampling and holding unit switches to the sampling state from the holding state.

10. The adapter according to claim 1 , further comprising:
a voltage adjusting unit, coupled to the power converter, and configured to detect and adjust the output voltage of the adapter,
wherein the current sampling controller is coupled to the voltage adjusting unit, and configured to adjust the peak value of the current with the first pulsating waveform by the voltage adjusting unit.

11. The adapter according to claim 1 , wherein the sampling and holding unit comprises:
a current sampling unit, coupled to the power converter, and configured to detect the current with the first pulsating waveform to obtain a sampling current, and to convert the sampling current to a sampling voltage, the sampling voltage indicating a magnitude of the current with the first pulsating waveform;
a current holding unit, coupled to the current sampling unit and the current sampling controller respectively, and configured to receive the sampling voltage from the current sampling unit, and to charge a capacitor in the current holding unit based on the sampling voltage, wherein the current sampling controller is configured to sample the peak value of the current with the first pulsating waveform based on a voltage across both ends of the capacitor in the sampling and holding unit.

12. The adapter according to claim 1 , wherein the current sampling controller comprises an analog-to-digital converter, and the current sampling controller is configured to sample the peak value of the current with the first pulsating waveform based on the analog-to-digital converter.

13. The adapter according to claim 1 , wherein a charging speed of the adapter charging the device to be charged in the second charging mode is greater than a charging speed of the adapter charging the device to be charged in the first charging mode, the current with the first pulsating waveform is the output current of the adapter in the second charging mode, the adapter comprises a control unit, and the control unit is configured to perform a bidirectional communication with the device to be charged during the adapter is coupled with the device to be charged, so as to control an output of the adapter in the second charging mode.

14. The adapter according to claim 13 , wherein when the control unit performs the bidirectional

Assignees

• Guangdong Oppo Mobile Telecommunications Corp Ltd

Inventors

• Tian Chen
• Zhang Jialiang

Classifications

• H02M3/33507

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

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H02M7/217

  using semiconductor devices only · CPC title

• H02M3/335

  using semiconductor devices only · CPC title

• H02J2207/20

  Charging or discharging characterised by the power electronics converter · CPC title