CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a 35 U.S.C. § 371 National Phase conversion of International (PCT) Patent Application No. PCT/CN2017/115146 filed Dec. 8, 2017, which claims foreign priority of Chinese Patent Application No. 201611201927.7, filed on Dec. 23, 2016 in the State Intellectual Property Office of China, the contents of all of which are hereby incorporated by reference.

TECHNICAL FIELD

The present disclosure relates to the field of communications technologies, and more particularly, to a charging control system.

BACKGROUND

At present, a lot of terminal devices are provide with ancillary terminal devices, which need to be power-supplied to implement their functions. In the prior art, the terminal devices generally need additional software support to supply power for their ancillary terminal devices. However, after the terminal devices are powered off, in charging modes required for additional software support, it is impossible to charge these ancillary terminal devices by the terminal devices.

SUMMARY

The present disclosure provides a charging control system to solve the problem that after the terminal devices are powered off, in charging modes required for additional software support, it is impossible to charge these ancillary terminal devices.

To solve the above problem, the present disclosure provides a charging control system, which includes: a master device, including a first USB interface and a first charging management circuit, the first USB interface includes a D+ terminal, a D− terminal, a VBUS terminal and a ID terminal; at least one slave device, including a second USB interface and a second charging management circuit, the second USB interface includes a D+ terminal, a D− terminal and a VBUS terminal; and a gating control circuit including an input terminal and an output terminal, arranged in the master device or the slave device. The input terminal of the gating control circuit is coupled to the first USB interface and the second USB interface, and the output terminal of the gating control circuit is coupled to the first charging management circuit and the second charging management circuit to select and control a charging USB interface of the first charging management circuit and a charging USB interface of the second charging management circuit.

The gating control circuit includes a switch control circuit, and the switch control circuit further includes a first switch control unit, a second switch control unit, a third switch control circuit, and a fourth switch control circuit. The first switch control unit includes an input terminal and an output terminal. The input terminal of the first switch control unit connects the VBUS terminal of the first USB interface, and the output terminal of the first switch control unit connects the first charging management circuit to control the VBUS terminal of the first USB interface to supply power for the first charging management circuit. The second switch control unit includes an input terminal and an output terminal. The input terminal of the second switch control unit connects the VBUS terminal of the second USB interface, and the output terminal of the second switch control unit connects the first charging management circuit to control the VBUS terminal of the second USB interface to supply power for the first charging management circuit. The third switch control unit includes an input terminal and an output terminal. The input terminal of the third switch control unit connects the VBUS terminal of the first USB interface, and the output terminal of the third switch control unit connects the second charging management circuit to control the VBUS terminal of the first USB interface to supply power for the second charging management circuit. The fourth switch control unit includes an input terminal and an output terminal. The input terminal of the fourth switch control unit connects the VBUS terminal of the second USB interface, and an output terminal of the fourth switch control unit connects the second charging management circuit to control the VBUS terminal of the second USB interface to supply power for the second charging management circuit.

The gating control circuit further includes a first determination control circuit, a second determination control circuit, a first logic control circuit, and a second logic control circuit. The first determination control circuit includes an input terminal and an output terminal. The input terminal of the first determination control circuit connects the D+ terminal and the D− terminal of the first USB interface to control an output state of the first determination control circuit based on a connection state between the D+ terminal and the D− terminal of the first USB interface. The second determination control circuit includes an input terminal and an output terminal. The input terminal of the second determination control circuit connects the D+ terminal and the D− terminal of the second USB interface to control an output state of the second determination control circuit based on a connection state between the D+ terminal and the D− terminal of the second USB interface. The first logic control circuit includes an input terminal and an output terminal. The input terminal of the first logic control circuit connects the ID terminal of the first USB interface and the output terminal of the second determination control circuit, and the output terminal of the first logic control circuit connects the first switch control unit to control on or off of the first switch control unit based on a level state of the ID terminal of the first USB interface and the output state of the second determination control circuit. The output terminal of the second determination control circuit further connects the input terminal of the second switch control unit to control on or off of the second switch control unit based on output of the second determination control circuit. The input terminal of the second logic control circuit connects the output terminal of the first determination control circuit, and the output terminal of the second logic control circuit connects the input terminal of the fourth switch control unit to control on or off of the fourth switch control unit based on the output state of the second determination control circuit. The output terminal of the first determination control circuit further connects the input terminal of the third switch control unit to control on or off of the third switch control unit based on the output state of the first determination control circuit.

The first determination control circuit further includes a first determination unit and a first control switch. The first determination unit includes an input terminal and an output terminal, and the first control switch includes an input terminal and an output terminal. The input terminal of the first determination unit connects the D+ terminal and the D− terminal of the first USB interface to determine whether the D+ terminal of the first USB interface is short-circuited with the D− terminal of the first USB interface. The input terminal of the first control switch connects the output terminal of the first determination unit to control on or off of the first control switch based on the connection state between the D+ terminal and the D− terminal of the first USB interface. The second determination control circuit further includes a second determination unit and a second control switch. The second determination unit includes an input terminal and an output terminal, and the second control switch includes an input terminal and an output terminal. The input terminal of the second determination unit connects the D+ terminal and the D− terminal of the second USB interface to determine whether the D+ terminal of the second USB interface is short-circuited with the D− terminal of the second USB interface. The input terminal of the second control switch connects the output terminal of the second determination unit to control on or off of the second control switch based on the connection state between the D+ terminal and the D− terminal of the second USB interface.

When the first determination unit determines that the D+ terminal of the first USB interface is short-circuited with the D− terminal of the first USB interface, the first determination unit controls the first control switch to be on. When the first determination unit determines that the D+ terminal of the first USB interface is not short-circuited with the D− terminal of the first USB interface, the first determination unit controls the first control switch to be off. When the second determination unit determines that the D+ terminal of the second USB interface is short-circuited with the D− terminal of the second USB interface, the second determination unit controls the second control switch to be on. When the second determination unit determines that the D+ terminal of the second USB interface is not short-circuited with the D− terminal of the second USB interface, the second determination unit controls the second control switch to be off.

The first logic control circuit further includes a first reverser and a multiplier. The first reverser includes an input terminal and an output terminal, and the multiplier includes an input terminal and an output terminal. The input terminal of the first reverser connects the output terminal of the second determination control circuit, the input terminal of the multiplier connects the ID terminal of the first USB interface and an output terminal of the first reverser, and the output terminal of the multiplier connects the first switch control unit to control on or off of the first switch control unit based on an output state of the multiplier. The second logic control circuit further includes a second reverser, the second reverser includes an input terminal and an output terminal. The input terminal of the second reverser connects the first determination control circuit, and the output terminal of the second reverser connects the fourth switch control unit to control on or off of the fourth switch control unit based on an output state of the second reverser.

The gating control module further includes a first current control circuit and a second current control circuit. The first current control circuit includes an input terminal and an output terminal. The input terminal of the first current control circuit connects the output terminal of the first determination control circuit and the output terminal of the second determination control circuit, and the output terminal of the first current control circuit connects the first charging management circuit to control charging current transmitted from the first charging management circuit to a first battery based on the output state of the first determination control circuit and the output state of the second determination control circuit. The second current control circuit includes an input terminal and an output terminal. The input terminal of the second current control circuit connects the output terminal of the first determination control circuit and the output terminal of the second determination control circuit, and the output terminal of the second current control circuit connects the second charging management circuit to control charging current transmitted from the second charging management circuit to a second battery based on the output state of the first determination control circuit and the output state of the second determination control circuit.

When the first determination control circuit is on and the second determination control circuit is off, or when the first determination control circuit is off and the second determination control circuit is on, the first current control circuit controls the first charging management circuit to transmit the charging current to the first battery of the master device based on a charging type, and the second current control circuit controls the second charging management circuit to transmit the charging current to the second battery of the salve device based on a charging type. When the first determination control circuit and the second determination control circuit are simultaneously off, or when the first determination control circuit and the second determination control circuit are simultaneously on, the first current control circuit controls the first charging management circuit to charge the first battery of the master device at a fixed charging current, and the second current control circuit controls the second charging management circuit to charge the second battery of the salve device at a fixed charging current.

The master device supports an On-The-Go (OTG) function, whereas the slave device does not support the OTG function.

When the master device enables the OTG function, the ID terminal of the first USB interface is a low level, and the VBUS terminal of the first USB interface is turned off.

In the charging control system of the present disclosure, the master device and the slave device are provided with a plurality of charging input circuit. The input terminal of the gating control circuit is coupled to the first USB interface of the master device and the second USB interface of the slave device, and the output terminal of the gating control circuit is coupled to the first charging management circuit of the master device and the second charging management circuit of the slave device. The gating control circuit selects and controls charging USB interfaces of the charging management circuits of the master device and the slave device by means of switch regulating and logical circuits to implement charging control in different modes without additional software support.

