CN110912224A - Charging device and charging device control method - Google Patents

Referring to fig. 1 to fig. 3, an embodiment of the invention provides a charging device, including: the device comprises a

power supply

1, a

voltage output circuit

2 connected with the

power supply

1, a

control module

3 electrically connected with the

power supply

1, a

detection circuit

4 connected with the

voltage output circuit

2 and the

control module

3, and a

USB interface

5 connected with the

detection circuit

4.

Referring to fig. 2, the

detection circuit

4 includes a

plugging detection circuit

41 connecting the

voltage output circuit

2 and the

USB interface

5, and an

MOS transistor

42 connected in parallel with the

plugging detection circuit

41 and used for turning on or off the

voltage output circuit

2 and the

USB interface

5, where the

MOS transistor

42 is connected to the

control module

3, and the

plugging detection circuit

41 forms a loop current when the charging device is plugged into the

USB interface

5, and generates a voltage at two ends of the

plugging detection circuit

41. The charging device can be a mobile phone, a Bluetooth headset, a tablet computer and the like.

When the

MOS transistor

42 is in the off state, when the

control module

3 detects that the voltage at the two ends of the

plug detection circuit

41 is greater than the first preset value, the

control module

3 determines that the charging device is inserted into the

USB interface

5 and controls the

MOS transistor

42 to be turned on, so that the

USB interface

5 outputs the charging voltage to charge the charging device.

When the

MOS transistor

42 is in the on state, the

control module

3 controls the

MOS transistor

42 to reduce the driving voltage at preset intervals, and detects the voltages at the two ends of the

plugging detection circuit

41, and when the

control module

3 detects that the voltages at the two ends of the

plugging detection circuit

41 are smaller than the second preset value, the

control module

3 determines that the charging device is plugged out of the

USB interface

5 and controls the

MOS transistor

42 to be kept off, so that the

USB interface

5 stops outputting the charging voltage.

In the embodiment of the present invention, the

control module

3 may be a single chip or an analog chip. In this embodiment, the

control module

3 is a single chip microcomputer. The

control module

3 inputs a low level to the

MOS transistor

42 at every predetermined time, so that the

MOS transistor

42 is turned off at every predetermined time to reduce the driving voltage of the

MOS transistor

42. The characteristic that the driving voltage of the

MOS transistor

42 is gradually reduced in the closing process is utilized to reduce the driving voltage of the

MOS transistor

42, and during the reduction of the driving voltage of the

MOS transistor

42, the impedance of the

MOS transistor

42 is gradually increased, so that a voltage difference is generated between two ends of the

plug detection circuit

41, if the charging device pulls out the

USB interface

5, the voltage between two ends of the

plug detection circuit

41 will be smaller than the second preset value, if the charging device does not pull out the

USB interface

5, the voltage between two ends of the

plug detection circuit

41 will be greater than or equal to the second preset value, and therefore the

control module

3 can judge whether the charging device pulls out the

USB interface

5 by detecting whether the voltage between two ends of the

plug detection circuit

41 is smaller than the second preset value.

The interval time of the

MOS tube

42 being closed every time by the

control module

3 can be set according to actual needs, so as to ensure that the driving voltage when the

MOS tube

42 is closed at every time is not reduced to zero, so that the

MOS tube

42 is not completely closed, and it can be ensured that the

control module

3 accurately detects the voltages at the two ends of the

plug detection circuit

41, thereby accurately judging whether the charging device is pulled out. If the driving voltage of the

MOS transistor

42 is not reduced at preset intervals by the

control module

3, the voltage at both ends of the

MOS transistor

42 approaches zero when the

MOS transistor

42 is turned on, and the

plug detection circuit

41 is in a short-circuit state, so that the voltage at both ends of the

plug detection circuit

41 cannot be detected.

In this embodiment, when the

MOS transistor

42 is in the on state, the

control module

3 turns off the

MOS transistor

42 once every 2 seconds, the power supply voltage of the

power supply

1 is 5V, and the initial driving voltage of the

MOS transistor

42 is 5V. During the closing process of the

MOS transistor

42, the driving voltage of the

MOS transistor

42 gradually decreases from 5V, and during this process, the

control module

3 detects the voltage across the

plug detection circuit

41. When the

control module

3 detects that the voltage at the two ends of the

plugging detection circuit

41 is smaller than the second preset value, the

control module

3 judges that the charging device is plugged out of the

USB interface

5, and at this time, the

control module

3 continuously outputs a low level to the

MOS transistor

42, so as to control the

MOS transistor

42 to be disconnected to stop the

USB interface

5 from outputting the charging voltage; if the

control module

3 detects that the voltages at the two ends of the

plug detection circuit

41 are greater than or equal to the second preset value in the closing process of the

MOS transistor

42, the

control module

3 determines that the charging device is not plugged out of the

USB interface

5, and at this time, the

control module

3 controls the

MOS transistor

42 to be turned on again and closes the

MOS transistor

42 once every preset time to reduce the driving voltage of the

MOS transistor

42, so as to detect whether the charging device is plugged out of the

USB interface

5 in real time.

According to the charging device provided by the embodiment of the invention, by arranging the

plugging detection circuit

41 which is connected with the

voltage output circuit

2 and the

USB interface

5 and the

MOS tube

42 which is connected with the

plugging detection circuit

41 in parallel and is used for conducting or disconnecting the

voltage output circuit

2 and the

USB interface

5, the

plugging detection circuit

41 forms loop current when the charging device is plugged into the

USB interface

5, and voltage is generated at two ends of the

plugging detection circuit

41. When the

MOS transistor

42 is in the off state, the

control module

3 detects whether the voltage at the two ends of the

plug detection circuit

41 is greater than the first preset value, so as to determine whether the

USB interface

5 is plugged into the charging device, thereby avoiding a situation that only the Lightning data line of the built-in chip is plugged into the

USB interface

5 and the charging device is erroneously determined to be plugged into the

USB interface

5, and improving the accuracy of detecting whether the charging device is plugged into the

USB interface

5; when the

MOS transistor

42 is in a conducting state, the driving voltage of the

MOS transistor

42 is reduced at preset time intervals by the

control module

3 to generate a voltage difference at two ends of the

plug detection circuit

41, and whether the voltage at two ends of the

plug detection circuit

41 is smaller than a second preset value is detected by the

control module

3 to determine whether the charging device is plugged out. When the

control module

3 detects that the voltage at the two ends of the

plugging detection circuit

41 is smaller than the second preset value, the

control module

3 judges that the charging device is plugged out of the

USB interface

5 and controls the

MOS tube

42 to be disconnected to stop the

USB interface

5 from outputting the charging voltage, so that whether the charging device is plugged out of the

USB interface

5 can be accurately detected, and it is avoided that a user is mistakenly judged that the charging device is not plugged out when the user only plugs out the iphone but does not plug out the iphone data line, so that the

USB interface

5 is timely stopped from outputting the charging voltage after the charging device plugs out the

USB interface

5.

In the embodiment of the present invention, the

MOS transistor

42 is a PMOS transistor or an NMOS transistor. The

MOS transistor

42 is connected to the

control module

3 through a current limiting resistor, so as to limit the current passing through the

MOS transistor

42 and prevent the

MOS transistor

42 from being damaged.

As an embodiment of the present invention, the plugging

detection circuit

41 includes a detection resistor R0 connected in parallel with the

MOS transistor

42, one end of the detection resistor R0 is connected to the

USB interface

5 and the source of the

MOS transistor

42, the other end of the detection resistor R0 is grounded and connected to the drain of the

MOS transistor

42, and the gate of the

MOS transistor

42 is connected to the

control module

3. Since the

MOS transistor

42 is connected in parallel with the detection resistor R0, the voltage across the

plug detection circuit

41 is the voltage across the detection resistor R0. In addition, the plugging

detection circuit

41 may be provided with two or more detection resistors connected in series.

In this embodiment, the gate of the

MOS transistor

42 is connected to the port GateX of the

control module

3, and the

MOS transistor

42 is connected to the

voltage output circuit

2 and the

USB interface

5, so as to control the on/off of the

MOS transistor

42, and control the on/off of the output voltage of the

USB interface

5. The

MOS tube

42 is controlled to be turned on when the port GateX of the

control module

3 outputs a high level, and the

MOS tube

42 is controlled to be turned off when the port GateX of the

control module

3 outputs a low level, so that the

MOS tube

42 is turned off. One end of the detection resistor R0 is connected to the pin GND of the

USB interface

5 and is connected to the source of the

MOS transistor

42 to form a node a, the other end of the detection resistor R0 is connected to the GND end of the

voltage output circuit

2 and is connected to the drain of the

MOS transistor

42 to form a node b, the pin VCC of the

USB interface

5 is connected to the Vbus end of the

voltage output circuit

2, and the voltage at the two ends of the plugging/unplugging

detection circuit

41 is the voltage Vab between the node a and the node b.

In this embodiment, when the

USB interface

5 is not plugged into the charging device, the plugging

detection circuit

41 does not form a path, the plugging

detection circuit

41 does not form a current, and the voltage Vab across the plugging

detection circuit

41 is zero. When a charging device is plugged into the

USB interface

5, the plugging

detection circuit

41 forms a path with the

USB interface

5 via a data line, and a loop current Iab passing through the plugging

detection circuit

41 is formed. At this time, since the

MOS transistor

42 is not turned on, the current passes through the detection resistors R0, Vab ═ Iab ═ R0 of the

plug detection circuit

41, if the lighting data line (the iphone data line) of the built-in chip is inserted into the

USB interface

5, the current is drawn less than 1mA, and if the charging device such as a mobile phone/bluetooth headset is inserted into the

USB interface

5, the current is drawn at least more than 10 mA. Because the resistance value of the detection resistor R0 is fixed, only the first preset value of Vab needs to be set, whether the

USB interface

5 is inserted into the charging equipment can be judged, and therefore whether the charging equipment is inserted into the USB interface can be reliably identified, and misjudgment is avoided.

The first preset value can be set according to the resistance of the detection resistor R0, for example, the resistance of the detection resistor R0 is 200 ohms, and the first preset value is set to 0.3V. When the Lightning data line is plugged into the

USB interface

5, the current passing through the detecting resistor R0 is less than 1mA, and therefore the voltage at the two ends of the detecting resistor R0 is less than 0.2V, and therefore when the Lightning data line is plugged into the

USB interface

5, the voltage Vab at the two ends of the plugging detecting

circuit

41 detected by the

control module

3 is less than 0.3V, so that it can be accurately determined that no charging device is plugged into the

USB interface

5, the

MOS transistor

42 is not turned on at this time, and the

USB interface

5 does not output the charging voltage.

In the embodiment of the present invention, after the

control module

3 determines that the charging device is plugged into the

USB interface

5 and controls the

MOS transistor

42 to be turned on to enable the

USB interface

5 to output a voltage to charge the charging device, the

MOS transistor

42 is turned off at preset intervals by the

control module

3, so as to reduce the driving voltage of the

MOS transistor

42 to increase the impedance of the

MOS transistor

42, so as to generate a voltage difference at two ends of the

plug detection circuit

41, and thus, whether the voltage Vab at two ends of the

plug detection circuit

41 is smaller than a second preset value can be accurately detected by the

control module

3 to determine whether the charging device is plugged out.

As shown in fig. 4, the impedance of the

MOS transistor

42 increases with the decrease of the driving voltage VGS of the

MOS transistor

42, and the current Ids passing through the

MOS transistor

42 decreases, so that a voltage difference is generated between the two ends Vab of the plugging

detection circuit

41. In this embodiment, when the

control module

3 controls the

MOS transistor

42 to be turned off, the driving voltage VGS of the

MOS transistor

42 is gradually reduced from 5V, and in this process, the

control module

3 detects the voltage Vab at two ends of the plugging

detection circuit

41. When the charging device is not unplugged from the

USB interface

5, the voltage Vab at two ends of the plugging

detection circuit

41 is greater than or equal to the second preset value; when the voltage Vab at the two ends of the plugging

detection circuit

41 is smaller than the second preset value, it represents that the charging device plugs out the

USB interface

5. If the

control module

3 detects that the voltage Vab at the two ends of the plugging

detection circuit

41 is greater than or equal to the second preset value, the

control module

3 determines that the charging device is not plugged out of the

USB interface

5 and keeps the

MOS transistor

42 turned on, and reduces the driving voltage of the

MOS transistor

42 at preset intervals to detect whether the charging device is plugged out of the

USB interface

5 in real time, so that the

control module

3 continuously detects whether the charging device is plugged out of the

USB interface

5 by controlling the turning-off and turning-on of the

MOS transistor

42. When the

control module

3 detects that the voltage Vab at the two ends of the plugging

detection circuit

41 is smaller than the second preset value, the

control module

3 judges that the charging device is plugged out of the

USB interface

5 and controls the

MOS tube

42 to be disconnected to stop the

USB interface

5 from outputting the charging voltage, so that whether the charging device is plugged out of the

USB interface

5 can be accurately detected, and it is avoided that a user is mistakenly judged that the charging device is not plugged out when the user only plugs out the apple phone without plugging out the data line of the apple phone, so that the

USB interface

5 is timely stopped from outputting the charging voltage after the charging device plugs out the

USB interface

5.

The setting value of the second preset value may be the same as or different from the first preset value, and both the second preset value and the first preset value are greater than zero, specifically set according to the resistance value of the plugging

detection circuit

41. In this embodiment, the second preset value is also set to 0.3V. When the charging device pulls out the

USB interface

5, the current passing through the detection resistor R0 is equal to zero, or only the apple phone is pulled out without pulling out the Lightning data line of the apple phone, and the current passing through the detection resistor R0 is smaller than 1mA, so the voltages at the two ends of the detection resistor R0 are both smaller than 0.2V and smaller than the second preset value of 0.3V, which prevents the apple data line from being pulled out and misjudging that the charging device is in a charging state, thereby accurately judging that the charging device pulls out the

USB interface

5, and at this time, the

control module

3 controls the

MOS transistor

42 to be turned off, so that the

USB interface

5 does not output a charging voltage.

In the embodiment of the invention, the charging device further comprises a

voltage stabilizing module

6, and the

control module

3 is connected with the

power supply

1 through the

voltage stabilizing module

6. The Vdd terminal of the

control module

3 is connected to the

voltage stabilizing module

6, the GND terminal of the

control module

3 is grounded, and the

voltage stabilizing module

6 plays a role in stabilizing, so that the working voltage of the

control module

3 is stable.

As an embodiment of the present invention, the number of the

USB interfaces

5 and the number of the

detection circuits

4 are at least two, and each

USB interface

5 is correspondingly connected to one

detection circuit

4, so as to facilitate to charge a plurality of charging devices simultaneously. Besides, the number of the

USB interface

5 and the

detection circuit

4 may be set to only one. In the present embodiment, the number of the

USB interface

5 and the

detection circuit

4 is three.

In this embodiment, when the

MOS transistor

42 corresponding to each

USB interface

5 is in the off state, and when the

control module

3 detects that the voltage Vab at the two ends of the

plug detection circuit

41 is greater than the first preset value, the

control module

3 determines that the charging device is inserted into the

USB interface

5 and drives the

MOS transistor

42 to be turned on, so that the

USB interface

5 outputs the charging voltage to charge the charging device.

When the

MOS transistor

42 corresponding to each

USB interface

5 is in a conducting state, the

control module

3 reduces the driving voltage of the

MOS transistor

42 at preset time intervals, and detects the voltage Vab at two ends of the plugging

detection circuit

41, and when the

control module

3 detects that the voltage Vab at two ends of the plugging

detection circuit

41 is smaller than a second preset value, the

control module

3 determines that the charging device is plugged out of the

USB interface

5 and controls the

MOS transistor

42 to be disconnected, so as to stop the

USB interface

5 from outputting the charging voltage.

As an embodiment of the present invention, the charging device further includes a

charging protocol module

7 connected to the

voltage output circuit

2 and the

control module

3, respectively, and the

charging protocol module

7 is simultaneously connected to each

USB interface

5. Wherein, the

charging protocol module

7 is connected with the port En1 of the

control module

3. In this embodiment, the

charging protocol module

7 is an identification chip.

When the

control module

3 detects that a charging device is inserted into one

USB interface

5, the

control module

3 sends a first control signal to the

charging protocol module

7, and the

charging protocol module

7 receives the first control signal and controls the

voltage output circuit

2 to output a charging voltage corresponding to the charging device to the

USB interface

5 according to the charging voltage of the charging device; when the

control module

3 detects that two or

more USB interfaces

5 are plugged into the charging device, the

control module

3 sends a second control signal to the

charging protocol module

7, and the

charging protocol module

7 receives the second control signal and controls the

voltage output circuit

2 to output a preset charging voltage to the USB interfaces 5. The first control signal is a high level signal, and the second control signal is a low level signal.

In this embodiment, when the

control module

3 detects that any one

USB interface

5 is inserted into the charging device, the

control module

3 drives the

MOS transistor

42 corresponding to the

USB interface

5 to be turned on, the

control module

3 outputs a high level signal to the

charging protocol module

7, the

charging protocol module

7 identifies the charging voltage of the charging device through a handshake protocol, and controls the

voltage output circuit

2 to output the charging voltage corresponding to the charging device to the

USB interface

5, so as to realize the quick charging of the charging device.

When the

control module

3 detects that the

second USB interface

5 is inserted into the charging device, that is, when it detects that the two

USB interfaces

5 are inserted into the charging device, the

control module

3 drives the

MOS transistors

42 corresponding to the

second USB interface

5 to be turned on, at this time, the

control module

3 outputs a low level signal to the

charging protocol module

7, and the

charging protocol module

7 receives the low level signal and controls the

voltage output circuit

2 to output a preset charging voltage to the

USB interface

5. The preset voltage is 5V, so that two or more charging devices can realize common charging. The two charging devices realize that the common charging is not allowed to enter a quick charging mode; similarly, when the

control module

3 detects that the

third USB interface

5 is inserted into the charging device, that is, when it detects that more than two

USB interfaces

5 are inserted into the charging device, the

control module

3 drives the

MOS transistor

42 corresponding to the

third USB interface

5 to be turned on, at this time, the

control module

3 outputs a low level signal to the

charging protocol module

7, and the

charging protocol module

7 receives the low level signal and controls the

voltage output circuit

2 to output a preset voltage to the

USB interface

5, so that the three charging devices all realize normal charging. When any one

USB interface

5 is detected to be inserted into one charging device to realize the quick charging of the charging device, and two or two

USB interfaces

5 are detected to be inserted into the charging device to realize the common charging, the requirements of the quick charging and the common charging can be met, the total power is not increased, and the production cost is effectively reduced.

In the embodiment of the present invention, the

voltage output circuit

2 includes a resistor R7 and a resistor R8, one end of the resistor R7 is connected to the

power supply

1, the other end of the resistor R8 is connected to one end of the resistor R8, the other end of the resistor R8 is grounded, and the pin FB of the

charging protocol module

7 is connected between the resistor R7 and the resistor R8. One end of the resistor R7 is connected with the Vout end of the

power supply

1, one end of the resistor R8 connected with the resistor R7 is connected with the Vfb end of the

power supply

1, and the other end of the resistor R8 is connected with the GND end of the

power supply

1.

In the embodiment of the present invention, the

charging protocol module

7 precisely controls the output voltage of the

voltage output circuit

2 by adjusting the magnitude of the source current or sink current of the pin FB, so as to output a corresponding charging voltage according to the charging voltage of the charging device. For example, when the resistor R7 is 100k ohms and the

USB interface

5 needs to output a voltage of 9V, the FB pin of the

charging protocol module

7 draws a current of 40uA, so that the voltage of the

USB interface

5 can be changed from 5V to a voltage of 9V for output; when the

USB interface

5 needs to output 12V voltage, the FB pin of the

charging protocol module

7 needs to pull current 70uA, so that the voltage of the

USB interface

5 can be changed from 5V to 12V voltage for output; when the

USB interface

5 outputs a voltage of 5V, the FB pin of the

charging protocol module

7 neither draws current nor sinks current, and the voltage of the

USB interface

5 outputs a voltage of 5V.

Referring to fig. 3, in detail, the

detection circuit

4 includes a first detection circuit, a second detection circuit and a third detection circuit, the

USB interface

5 includes a

first USB interface

51, a

second USB interface

52 and a

third USB interface

53, and the

first USB interface

51, the

second USB interface

52 and the

third USB interface

53 are respectively connected to the

charging protocol module

7.

The first detection circuit comprises a first plug detection circuit connected with the

voltage output circuit

2 and the

first USB interface

51 and a first MOS tube Q1 which is connected with the first plug detection circuit in parallel and used for connecting or disconnecting the

voltage output circuit

2 and the

first USB interface

51, the first MOS tube Q1 is connected with the

control module

3, the first plug detection circuit forms loop current when the charging equipment is inserted into the

first USB interface

51, and voltage is generated at two ends of the first plug detection circuit. The first plug detection circuit includes a first detection resistor R4, a Gate of the first MOS transistor Q1 is connected to a port Gate1 of the

control module

3 through a first current limiting resistor R1, one end of the first detection resistor R4 is connected to a pin GND of the

first USB interface

51, a source of the first MOS transistor Q1, and a port Point1 of the

control module

3, the other end of the first detection resistor R4 is grounded and connected to a drain of the first MOS transistor Q1, a pin VCC of the

first USB interface

51 is connected to one end of the resistor R7, which is connected to a Vout end of the

power supply

1, and a pin D + of the

first USB interface

51 and a pin D-of the

first USB interface

51 are connected to the

charging protocol module

7, respectively.

The second detection circuit comprises a second plug detection circuit connected with the

voltage output circuit

2 and the

second USB interface

52 and a second MOS tube Q2 which is connected with the second plug detection circuit in parallel and used for connecting or disconnecting the

voltage output circuit

2 and the

second USB interface

52, the second MOS tube Q2 is connected with the

control module

3, the first plug detection circuit forms loop current when the charging equipment is inserted into the

second USB interface

52, and voltage is generated at two ends of the first plug detection circuit. The first plug detection circuit includes a second detection resistor R5, a Gate of the second MOS transistor Q2 is connected to a port Gate2 of the

control module

3 through a second current limiting resistor R2, one end of the second detection resistor R5 is connected to a pin GND of the

second USB interface

52, a source of the second MOS transistor Q2, and a port Point2 of the

control module

3, the other end of the second detection resistor R5 is grounded and connected to a drain of the second MOS transistor Q2, a pin VCC of the

second USB interface

52 is connected to one end of the resistor R7, which is connected to a Vout end of the

power supply

1, and a pin D + of the

second USB interface

52 and a pin D-of the

second USB interface

52 are connected to the

charging protocol module

7.

The third detection circuit comprises a third plug detection circuit connected with the

voltage output circuit

2 and the

third USB interface

53, and a third MOS transistor Q3 connected in parallel with the third plug detection circuit and used for turning on or off the

voltage output circuit

2 and the

third USB interface

52, the third MOS transistor Q3 is connected with the

control module

3, the third plug detection circuit forms a loop current when the charging device is inserted into the

third USB interface

53, and generates a voltage at two ends of the third plug detection circuit. The third plug detection circuit includes a third detection resistor R6, a Gate of the third MOS transistor Q3 is connected to a port Gate3 of the

control module

3 through a third current limiting resistor R3, one end of the third detection resistor R6 is connected to a pin GND of the

third USB interface

53, a source of the third MOS transistor Q3, and a port Point3 of the

control module

3, the other end of the third detection resistor R6 is grounded and connected to a drain of the third MOS transistor Q3, a pin VCC of the

third USB interface

53 is connected to one end of the resistor R7, which is connected to the Vout end of the

power supply

1, and a pin D + of the

third USB interface

53 and a pin D-of the

third USB interface

53 are connected to the

charging protocol module

7, respectively.

When the second MOS transistor Q2 is in an off state, when the port Point2 of the

control module

3 detects that the voltage at two ends of the second plug detection circuit is greater than the first preset value, at this time, the

control module

3 determines that the charging device is inserted into the

second USB interface

52, and the port Gate2 of the

control module

3 outputs a high level to drive the second MOS transistor Q2 to be turned on, so that the

second USB interface

52 outputs a charging voltage to charge the charging device; otherwise, when the voltage detected by the port Point2 of the

control module

3 is less than or equal to the first preset value, the port Gate2 of the

control module

3 outputs a low level, and the second MOS transistor Q2 is not turned on. When the second MOS transistor Q2 is in a conducting state, the

control module

3 reduces the driving voltage of the second MOS transistor Q2 at preset time intervals, in this process, when the port Point2 of the

control module

3 detects that the voltage at the two ends of the second plugging detection circuit is smaller than a second preset value, at this time, the

control module

3 determines that the charging device is plugged out of the

second USB interface

52, and the port Gate2 of the

control module

3 outputs a low level to drive the second MOS transistor Q2 to be turned off; if the port Point2 of the

control module

3 detects that the voltage at the two ends of the second plug detection circuit is greater than or equal to the second preset value, at this time, the

control module

3 determines that the charging device is not plugged out of the

second USB interface

52, and the

control module

3 reduces the driving voltage of the second MOS transistor Q2 at preset intervals to detect whether the charging device is plugged out of the

second USB interface

52 in real time.

When the third MOS transistor Q3 is turned on and off, when the voltage detected by the port Point3 of the

control module

3 is greater than the first preset value, at this time, the

control module

3 determines that the charging device is inserted into the

third USB interface

53, and the port Gate3 of the

control module

3 outputs a high level to drive the third MOS transistor Q3 to turn on, so that the

third USB interface

53 outputs a charging voltage to charge the charging device; otherwise, when the voltage detected by the port Point3 of the

control module

3 is less than or equal to the first preset value, the port Gate3 of the

control module

3 outputs a low level, and the third MOS transistor Q3 is not turned on. When the third MOS transistor Q3 is in a conducting state, the

control module

3 reduces the driving voltage of the third MOS transistor Q3 at preset time intervals, in this process, when the port Point3 of the

control module

3 detects that the voltage at the two ends of the third plugging detection circuit is smaller than the second preset value, at this time, the

control module

3 determines that the charging device is plugged out of the

third USB interface

53, and the port Gate3 of the

control module

3 outputs a low level to drive the third MOS transistor Q3 to be turned off; if the port Point3 of the

control module

3 detects that the voltage at the two ends of the third plugging detection circuit is greater than or equal to the second preset value, at this time, the

control module

3 determines that the charging device is not plugged out of the

third USB interface

53, and the

control module

3 reduces the driving voltage of the third MOS transistor Q3 at preset intervals to detect whether the charging device is plugged out of the

third USB interface

53 in real time.

When the port Gate1, the port Gate2 or the port Gate3 of the

control module

3 outputs a high level, which represents that one

USB interface

5 is plugged into the charging device, a counter n is introduced, and n counts once, for example, when the counter n is equal to 3, which represents that three

USB interfaces

5 are plugged into the charging device, by the above-mentioned detection method for detecting the plugging and unplugging of the charging device, when the charging device of one

USB interface

5 is unplugged, the counter n is decremented by 1, which represents that the charging device of 1

USB interface

5 is unplugged. When the counter n is equal to 1, it represents that only one

USB interface

5 is inserted into the charging device, at this time, the port En1 of the

control module

3 is set to high level, the

charging protocol module

7 receives a high level signal, and the

charging protocol module

7 controls the

voltage output circuit

2 to output the charging voltage of the corresponding charging device to the

USB interface

5 according to the charging voltage of the charging device, so as to implement fast charging. When the counter n >1, it represents that two or

more USB interfaces

5 are plugged into the charging device, the port En1 of the

control module

3 is set to low level, and the

charging protocol module

7 receives the low level signal and controls the

voltage output circuit

2 to output a preset charging voltage to the

USB interfaces

5, so as to implement a normal charging function.

step S1, when the

MOS transistor

42 is in the off state, the

control module

3 detects the voltage at the two ends of the

plug detection circuit

41;

in this step, when the

MOS transistor

42 corresponding to each

USB interface

5 is in the off state, that is, the

USB interface

5 is in the off state, it is determined whether a charging device is inserted by detecting the voltage Vab at the two ends of the

plug detection circuit

41.

Step S2, the

control module

3 determines whether the voltage Vab at the two ends of the

plug detection circuit

41 is greater than a first preset value; if yes, go to the next step S3; if not, returning to the previous step S1;

in this step, when the

control module

3 determines that the voltage Vab at the two ends of the plugging

detection circuit

41 is greater than the first preset value, it represents that the charging device is plugged into the

USB interface

5, and the

control module

3 inputs a high level to the

MOS transistor

42 to turn on the

MOS transistor

42, so that the

USB interface

5 outputs a charging voltage to charge the charging device.

Step S3, the

control module

3 determines that there is a charging device inserted into the

USB interface

5 and controls the

MOS transistor

42 to be turned on, so that the

USB interface

5 outputs a charging voltage to charge the charging device;

as an embodiment of the present invention, when the number of the

USB interface

5 and the

plug detection circuit

41 is one, and the

MOS

42 corresponding to the

USB interface

5 is in the off state, and when the

control module

3 detects that the voltage at two ends of the

plug detection circuit

41 is greater than the first preset value, the

control module

3 determines that the charging device is inserted into the

USB interface

5 and drives the

MOS

42 to be turned on, so that the

USB interface

5 outputs the preset charging voltage to charge the charging device. The preset charging voltage is 5V, and common charging of the charging equipment is achieved.

As another embodiment of the present invention, when the number of the

USB interfaces

5 and the plugging

detection circuit

41 is two, the charging apparatus further includes a

charging protocol module

7 connected to the

voltage output circuit

2 and the

control module

3, respectively, and the

charging protocol module

7 is connected to each

USB interface

5 at the same time.

When the

control module

3 detects that a charging device is inserted into one

USB interface

5, the

control module

3 sends a first control signal to the charging protocol module, and the

charging protocol module

7 receives the first control signal and controls the

voltage output circuit

2 to output the charging voltage corresponding to the charging device to the

USB interface

5 according to the charging voltage of the charging device; when the

control module

3 detects that two or

more USB interfaces

5 are plugged into the charging device, the

control module

3 sends a second control signal to the

charging protocol module

7, and the

charging protocol module

7 receives the second control signal and controls the

voltage output circuit

2 to output a preset charging voltage to the USB interfaces 5.

In this embodiment, when the

control module

3 detects that any one

USB interface

5 is inserted into the charging device, the

control module

3 switches on the

MOS transistor

42 corresponding to the

USB interface

5, the

control module

3 outputs a high level signal to the

charging protocol module

7, the

charging protocol module

7 identifies the charging voltage of the charging device through a handshaking protocol, and the

voltage output circuit

2 is controlled to output the charging voltage corresponding to the charging device to the

USB interface

5, so as to realize the quick charging of the charging device.

When the

control module

3 detects that the

second USB interface

5 is inserted into the charging device, that is, when it detects that the two

USB interfaces

5 are inserted into the charging device, the

control module

3 drives the

MOS transistor

42 corresponding to the

second USB interface

5 to be turned on, at this time, the

control module

3 outputs a low level signal to the

charging protocol module

7, and the

charging protocol module

7 receives the low level signal and controls the

voltage output circuit

2 to output a preset charging voltage to the

USB interfaces

5, so as to implement normal charging of two or more charging devices. Therefore, when any one

USB interface

5 is detected to be inserted into one charging device to realize the quick charging of the charging device, and two or two

USB interfaces

5 are detected to be inserted into the charging device to realize the ordinary charging, the requirements of the quick charging and the ordinary charging can be met, the total power is not increased, and the production cost is effectively reduced.

Step S4, when the

MOS transistor

42 is in the on state, the

control module

3 controls the

MOS transistor

42 to reduce the driving voltage and detect the voltages at the two ends of the

plug detection circuit

41 at preset intervals;

in this step, the

MOS tube

42 is controlled to reduce the driving voltage of the

MOS tube

42 at intervals of a preset time by the

control module

3, so that a voltage difference is generated at two ends of the

plug detection circuit

41, and the

control module

3 detects the voltages at two ends of the

plug detection circuit

41 to determine whether the charging device is plugged out in real time.

Step S5, the

control module

3 determines whether the voltage Vab at the two ends of the

plug detection circuit

41 is smaller than a second preset value; if yes, go to the next step S6; if not, returning to the previous step S4;

in this step, in the on state of the

MOS transistor

42, the

control module

3 determines whether the voltage Vab at the two ends of the

plug detection circuit

41 is smaller than the second preset value, so as to accurately detect whether the charging device is plugged out of the

USB interface

5, thereby avoiding the situation that the user is mistakenly determined that the charging device is not plugged out when the user only plugs out the apple-phone but does not plug out the lighting data line. When the

control module

3 detects that the voltage at the two ends of the

plug detection circuit

41 is greater than or equal to the second preset value, the

control module

3 determines that the charging device is not plugged out of the

USB interface

5 and keeps the

MOS transistor

42 turned on, so that the

USB interface

5 continues to output the charging voltage to charge the charging device, and the

control module

3 continues to reduce the driving voltage of the

MOS transistor

42 every preset time interval and detects the voltage at the two ends of the

plug detection circuit

41, so as to detect whether the charging device is plugged out in real time.

In step S6, the

control module

3 determines that the charging device has pulled out the USB interface and controls the MOS transistor to be disconnected, so that the

USB interface

5 stops outputting the charging voltage.

In this step, when the

control module

3 detects that the voltage at the two ends of the

plug detection circuit

41 is smaller than the second preset value, the

control module

3 determines that the charging device has pulled out the USB interface and drives the MOS transistor to be disconnected to stop the USB interface from outputting the charging voltage, so that the

USB interface

5 stops outputting the charging voltage in time after the charging device has pulled out the

USB interface

5. After the

MOS transistor

42 is in the off state, the

control module

3 detects the voltages at the two ends of the

plug detection circuit

41 in real time to determine whether a charging device is plugged.