CN113629801B

CN113629801B - Power supply device

Info

Publication number: CN113629801B
Application number: CN202110800698.5A
Authority: CN
Inventors: 姚钦峰; 蓝元刘
Original assignee: Shenzhen Tiandeyu Technology Co ltd
Current assignee: Shenzhen Tiandeyu Technology Co ltd
Priority date: 2021-07-15
Filing date: 2021-07-15
Publication date: 2023-01-17
Anticipated expiration: 2041-07-15
Also published as: CN113629801A

Abstract

The present invention provides a power supply device, including: a power supply; at least two interfaces; the control module comprises a detection unit, a voltage limiting unit and a comparison unit, wherein the detection unit comprises a first switch and a detection element, and the voltage limiting unit comprises a second switch and a voltage limiting element; the interface and the first switch are connected in series between the power supply and the ground, one end of the detection element is electrically connected between the interface and the first switch, the other end of the detection element is grounded, the second switch is connected in series with the voltage limiting element, the second switch and the voltage limiting element which are connected in series are connected in parallel between the interface and the first switch, the input end of the comparison unit is electrically connected between the first switch and the interface, and the output end of the comparison unit is used for outputting a control signal to control the first switch and the second switch to be switched on or switched off. The power supply device provided by the invention can effectively clamp the voltage at two ends of the interface.

Description

Power supply device

Technical Field

The invention relates to the field of charging, in particular to a power supply device.

Background

In the conventional multi-port power supply device, because a plurality of ports are connected in parallel, when charging equipment is connected to the power supply device, other ports which are not connected with the charging equipment also have higher voltage. Thus, there is a certain safety risk when a charging device that cannot withstand high voltage is inserted into the port.

Disclosure of Invention

In view of the above, the present invention provides a power supply apparatus for connecting a plurality of charging devices, the power supply apparatus including:

a power supply;

at least two interfaces;

the control modules are connected with the interfaces in a one-to-one correspondence mode, each control module comprises a detection unit, a voltage limiting unit and a comparison unit, each detection unit comprises a first switch and a detection element, and each voltage limiting unit comprises a second switch and a voltage limiting element;

the interface and the first switch are connected in series between the power supply and the ground, one end of the detection element is electrically connected between the interface and the first switch, the other end of the detection element is grounded, the second switch is connected in series with the voltage limiting element, one end of the second switch and one end of the voltage limiting element which are connected in series are electrically connected to the power supply, the other end of the second switch and the voltage limiting element are connected between the interface and the first switch, the input end of the comparison unit is electrically connected between the first switch and the interface, and the output end of the comparison unit is used for outputting a control signal to control the first switch and the second switch to be switched on or switched off.

According to the invention, the control modules are arranged at the two ends of the interface and comprise the detection unit, the voltage limiting unit and the comparison unit, and when the detection unit and the comparison unit determine that the interface is inserted into the charging equipment, the voltages at the two ends of other interfaces which are not connected with the charging equipment and are positioned on the same power supply device are limited within a safe voltage range, so that the interface of the power supply device with multiple ports is prevented from generating larger voltage, and the safety risk when the interface is connected with other charging equipment is reduced.

Drawings

Fig. 1 is a schematic diagram of a power supply apparatus and a plurality of charging devices according to the present invention.

Fig. 2 is a functional block diagram of the power supply apparatus shown in fig. 1.

Fig. 3 is a block diagram of a circuit structure of the power supply apparatus shown in fig. 1 according to an embodiment.

Fig. 4 is a block diagram of a circuit structure of the power supply apparatus shown in fig. 1 according to another embodiment.

Fig. 5 is a block diagram of a circuit structure of the power supply apparatus shown in fig. 1 according to another embodiment.

Description of the main elements

Power feeding device

100, 100a, 100b

Supply power VBUS

Interface 10

VSB (vestigial side wall) of power supply pin

Grounding pin GND

Control module

20, 20a, 20b

Detection units 21, 21a

First switch S1

First ends S11 to S81

Second ends S12 to S82

Third terminals S13 to S83

Detecting

elements

211, 211a, 211b

First resistor R1

First current source I1

Pressure limiting unit 22

Second switch S2

Voltage limiting element 221

Voltage-stabilizing diodes D1, D2

Comparison units

23, 23b

Comparator A1

First input terminal 231

Second input terminal 232

Output terminal 233

Reference voltage units

234a, 234b

Control signal Vout

Control switch S3

Voltage stabilizing elements 221a and 221b

Second current source I2

Reference voltage source V0

First reference switch S4

First comparison switch S5

Second reference switch S6

Second comparison switch S7

Third reference switch S8

Second resistor R2

First reference current source VB1

Second reference current source VB2

Third reference current source VB3

Charging device 200

Connector 210

Battery pack 220

The following detailed description will further illustrate the invention in conjunction with the above-described figures.

Detailed Description

It will be understood that when an element is referred to as being "electrically connected" to another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "electrically connected" to another element, it can be connected by contact, e.g., by wires, or by contactless connection, e.g., by contactless coupling.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

Referring to fig. 1, a power supply apparatus 100 for electrically connecting a plurality of charging devices 200 to charge the charging devices 200 is provided in an embodiment of the present invention.

In this embodiment, the power supply apparatus 100 and the charging device 200 may be devices supporting Universal Serial Bus (USB) specification. The power supply apparatus 100 may be a USB device with multiple ports, such as a mobile power source with multiple ports or a USB adapter with multiple ports.

Referring to fig. 2, the power supply apparatus 100 includes a power supply VBUS, at least two interfaces 10, and at least two control modules 20.

Wherein, the power supply VBUS can output dc voltages with different voltage values, such as 5V, 9V or 12V.

Each of the interfaces 10 is configured to be electrically connected to the power supply VBUS and the corresponding charging apparatus 200 to supply power to the charging apparatus 200.

In this embodiment, the interface 10 is a Type-a interface. The charging device 200 includes a connector 210. The connector 210 is also a Type-a interface. As such, the interface 10 is connected with the charging apparatus 200 through the connector 210.

It is understood that, when the connector 210 is plugged into the interface 10, the power supply VBUS forms a current loop with the charging device 200 through the interface 10 and the connector 210. At this time, the power supply VBUS supplies power to the battery pack 220 of the charging apparatus 200 through the interface 10 and the connector 210.

The control modules 20 are connected to the interfaces 10 in a one-to-one correspondence manner, and are configured to detect whether the charging device 200 is plugged into the corresponding interface 10, and limit voltages at two ends of other interfaces 10, which are not plugged into the charging device 200, on the power supply apparatus 100.

In this embodiment, the power supply VBUS may be further configured to receive an input voltage, such as an ac voltage, and output a dc voltage having a preset voltage value to provide power for the charging device 200.

In an alternative embodiment, the interface 10 includes a power pin VSB and a ground pin GND.

It is understood that the connector 210 also includes a power pin VSB and a ground pin GND. The power supply pin VSB of the connector 210 is correspondingly connected to the power supply pin VSB of the interface 10, and the ground pin GND of the connector 210 is correspondingly connected to the ground pin GND of the interface 10.

Referring to fig. 3, each of the control modules 20 includes a detecting unit 21, a voltage limiting unit 22, and a comparing unit 23.

In the present embodiment, the detecting unit 21 includes a first switch S1 and a detecting element 211. The voltage limiting unit 22 includes a second switch S2 and a voltage limiting element 221.

The interface 10 and the first switch S1 are connected in series between the power supply VBUS and ground. One end of the detection element 211 is electrically connected between the ground pin GND of the interface 10 and the first switch S1, and the other end of the detection element 211 is grounded. I.e. the detecting element 211 and the first switch S1 are connected in parallel between the ground pin GND and ground of the interface 10.

The second switch S2 is connected in series with the voltage limiting element 221, one end of the second switch S2 and one end of the voltage limiting element 221 which are connected in series are electrically connected to the power supply, and the other end is connected between a ground pin GND of the interface 10 and the first switch S1. That is, the second switch S2 and the voltage limiting element 221 are connected in series and then connected in parallel between the power pin VSB and the ground pin GND of the interface 10.

The input terminal of the comparing unit 23 is electrically connected between the ground pin GND of the interface 10 and the first switch S1, and the output terminal of the comparing unit 23 is used for outputting a control signal Vout. The control signal Vout is used to control the first switch S1 and the second switch S2 to be turned on or off. For example, when the control signal Vout is at a first level (e.g., high level), the control signal Vout controls the first switch S1 to be turned on and the second switch S2 to be turned off. When the control signal Vout is at a second level (e.g., a low level), the control signal Vout controls the first switch S1 to be turned off and the second switch S2 to be turned on. That is, the control signal Vout is used to control the first switch S1 and the second switch S2 to be in different states. For example, when the first switch S1 is in the on state, the second switch S2 is in the off state. When the first switch S1 is in the off state, the second switch S2 is in the on state.

Specifically, in this embodiment, the first switch S1 is an N-Channel Metal Oxide Semiconductor Field Effect Transistor (NMOS Transistor), the detecting element 211 is a first resistor R1, the second switch S2 is a P-Channel Metal Oxide Semiconductor Field Effect Transistor (PMOS Transistor), the voltage limiting element 221 is a zener diode D1, and the comparing unit 23 is a comparator A1, which is an example of a detailed circuit connection relationship.

Referring to fig. 3 again, the first switch S1 includes a first terminal S11, a second terminal S12 and a third terminal S13. The first terminal S11 of the first switch S1 is a drain, the second terminal S12 of the first switch S1 is a source, and the third terminal S13 of the first switch S1 is a gate.

The second switch S2 includes a first terminal S21, a second terminal S22 and a third terminal S23. The first terminal S21 of the second switch S2 is a source, the second terminal S22 of the second switch S2 is a drain, and the third terminal S23 of the second switch S2 is a gate.

The comparator A1 includes a first input 231, a second input 232, and an output 233. The first input 231 is a positive input, and the second input 232 is a negative input.

In this embodiment, the power pin VSB of the interface 10 is electrically connected to the power supply VBUS for receiving the power outputted from the power supply VBUS. The ground pin GND of the interface 10 is electrically connected to the first terminal S11 of the first switch S1, the second terminal S12 of the first switch S1 is grounded, and the third terminal S13 of the first switch S1 is used for receiving the control signal Vout. One end of the first resistor R1 is electrically connected between the ground pin GND of the interface 10 and the first input terminal 231, and the other end of the first resistor R1 is grounded. The first input 231 of the comparator A1 is electrically connected between the ground pin GND and the first end S11 of the first switch S1, and the second input 232 of the comparator A1 is used for receiving a reference voltage. The output terminal 233 of the comparator A1 is used for outputting the control signal Vout. A first terminal S21 of the second switch S2 is electrically connected between the power supply pin VSB and the power supply VBUS, a second terminal S22 of the second switch S2 is electrically connected to a cathode of the zener diode D1, and an anode of the zener diode D1 is electrically connected between the ground pin GND of the interface 10 and the first terminal S11 of the first switch S1. The third terminal S23 of the second switch S2 is used for receiving the control signal Vout.

It can be understood that the operation principle of the power supply device 100 is as follows:

when all the interfaces 10 of the power supply device 100 are not connected to the charging apparatus 200, each of the interfaces 10 is disconnected from the first resistor R1, so that the voltage of the first input terminal 231 is lower than the reference voltage of the second input terminal 232, the output terminal 233 outputs the control signal Vout, and the control signal Vout is at a second level. In this way, the control signal Vout controls the first switch S1 to maintain the off-state, and simultaneously controls the second switch S2 to maintain the on-state.

When the charging device 200 is connected to the power supply apparatus 100, the power supply VBUS, the interface 10 to which the charging device 200 is connected, and the first resistor R1 form an electric circuit. In this way, the voltage across the first resistor R1 is raised, so that the voltage at the first input end 231 of the comparator A1 is greater than the reference voltage at the second input end 232, the output end 233 of the comparator A1 outputs the control signal Vout, and the control signal Vout is at the first level. In this way, the control signal Vout controls the first switch S1 to maintain the on state, and simultaneously controls the second switch S2 to maintain the off state. At this time, the voltage across the interface 10 is no longer limited, and the interface 10 can perform fast charging on the charging device 200 using a high voltage. That is, the detection unit 21 and the comparison unit 23 jointly detect that the interface 10 is inserted into the charging apparatus 200. The power supply VBUS may further adjust an output voltage correspondingly, so as to perform high-voltage fast charging on the charging device 200.

It can be understood that, since the plurality of interfaces 10 on the power supply apparatus 100 are connected in parallel with each other, both ends of the other interfaces 10 on the power supply apparatus 100 to which the charging device 200 is not connected have the same voltage as both ends of the interface 10 to which the charging device 200 is connected. In addition, the voltage across the first resistor R1 is smaller than the reference voltage, that is, the voltage at the first input terminal 231 is smaller than the reference voltage at the second input terminal 232, so that the output terminal 233 of the comparator A1 outputs the control signal Vout, and the control signal Vout is at the second level. The control signal Vout controls the first switch S1 to maintain an off-state while controlling the second switch S2 to maintain an on-state. Since the second switch S2 and the first zener diode D1 are connected in series to two ends of the interface 10, the voltage across the interface 10 can be maintained as the breakdown voltage of the first zener diode D1 or the voltage across the interface 10 can be maintained as the voltage of the power supply VBUS.

It is understood that the first zener diode D1 is broken down when the power supply VBUS outputs a high voltage (e.g., 9V). As such, the voltage across the interface 10 is limited to the breakdown voltage of the voltage limiting element 221, e.g., 5V. When the power supply VBUS outputs a low voltage (e.g., 5V), the first zener diode D1 is not broken, and thus, the first zener diode D1 maintains an off state, i.e., the voltage across the interface 10 is the voltage of the power supply VBUS. In this way, the voltage across the interface 10 to which the charging apparatus 200 is not connected can be limited within a safer voltage range regardless of whether the power supply VBUS outputs a high voltage or a low voltage.

It can be understood that, since the power supply VBUS can output voltages having different voltage values, and the breakdown voltage of the first zener diode D1 is fixed, the voltage value of the reference voltage at the second input terminal 232 of the comparing unit 23 varies with the voltage across the detecting element 211.

For example, when the power supply VBUS outputs a voltage of 9V, since the breakdown voltage of the first zener diode D1 is 5V, when the charging device 200 is connected to the interface 10, the voltage across the corresponding first resistor R1 is greater than or equal to 4V, that is, the reference voltage input by the second input terminal 232 should be at least 4V, and it is only detected that the charging device 200 is plugged into the interface 10. Similarly, when the power supply VBUS outputs a voltage of 12V and the charging device 200 is connected to the interface 10, the voltage across the corresponding first resistor R1 is greater than or equal to 7V, that is, the reference voltage input by the second input end 232 should be at least 7V, and it is only detected that the charging device 200 is plugged into the interface 10.

Furthermore, it can be understood that when the detecting element 211 is the first resistor R1, and the charging device 200 is plugged into the corresponding interface 10, the current flowing through the first resistor R1 will vary according to the voltage of the power supply VBUS and the resistance of the charging device 200. When the current is too large, the first resistor R1 or other electronic components in the power supply device 100 are easily damaged.

Therefore, referring to fig. 4, in order to overcome the above problem, the present invention further provides a power supply apparatus 100a. The circuit configuration of the power feeding device 100a is substantially the same as that of the power feeding device 100. The difference is that the control module 20a of the power supply device 100a has a different circuit structure from the control module 20 of the power supply device 100.

In the present embodiment, the control module 20a and the control module 20 have substantially the same structure, and the difference mainly lies in: the control module 20a includes a detection unit 21a, the voltage limiting unit 22 and a comparison unit 23 and a reference voltage unit 234a. The detection unit 21a includes the first switch S1 and a detection element 211a. The detecting element 211a is a first current source I1. The comparison unit 23 includes the comparator A1. The reference voltage unit 234a includes a control switch S3, a voltage regulator 221a, a second current source I2 and a reference voltage source V0. The reference voltage unit 234a is used for providing a reference voltage for the second input terminal 232.

One end of the control switch S3 is electrically connected between the power supply VBUS and the first switch S1, and the other end of the control switch S3 is electrically connected to one end of the voltage stabilizing element 221 a. The other end of the voltage stabilizing element 221a is electrically connected to the input terminal of the second current source I2, and the output terminal of the second current source I2 is grounded. A negative electrode of the reference voltage source V0 is electrically connected between the voltage stabilizing element 221a and the second current source I2, and a positive electrode of the reference voltage source V0 is electrically connected to the second input terminal 232.

In the present embodiment, the control switch S3 includes a first terminal S31, a second terminal S32 and a third terminal S33.

The control switch S3 is a PMOS tube. The first end S31 of the control switch S3 is a source, the second end S32 of the control switch S3 is a drain, and the third end S33 of the control switch S3 is a gate.

The voltage stabilizing element 221a is a zener diode D2 having the same breakdown voltage as the zener diode D1.

The first current source I1 and the second current source I2 output the same current.

In this embodiment, the input terminal of the first current source I1 is electrically connected between the ground pin GND of the interface 10 and the first terminal S11 of the first switch S1, and the output terminal of the first current source I1 is grounded. A first terminal S31 of the control switch S3 is electrically connected between the power supply source VBUS and the first terminal S11 of the first switch S1, a second terminal S32 of the control switch S3 is electrically connected to the cathode of the zener diode D2, and a third terminal S33 of the control switch S3 is configured to receive the control signal Vout. The anode of the zener diode D2 is electrically connected to the input terminal of the second current source I2, and the output terminal of the second current source I2 is grounded. The cathode of the reference voltage source V0 is electrically connected between the input terminal of the second current source I2 and the anode of the zener diode D2, and the anode of the reference voltage source V0 is electrically connected to the second input terminal 232.

It is understood that, in the present embodiment, the voltage VREF at the second input terminal 232 is the sum of the voltage of the reference voltage source V0 and the voltage REFA across the second current source I2. The voltage at the first input terminal 231 is the voltage VGNDA across the first current source I1.

When the charging device 200 is not plugged into the interface 10 of the power supply apparatus 100, the voltage VGNDA across the first current source I1 is the same as the voltage REFA across the second current source I2. When the charging device 200 is plugged into the interface 10 of the power supply apparatus 100, the voltage across the first current source I1 rises to VGNDA1. It is understood that the voltage VGNDA1 includes the voltage VGNDA across the first current source I1 and a voltage V1 (not shown) generated by the power supply source VBUS flowing through the interface 10 and the first current source I1.

In this way, when the charging device 200 is plugged into the interface 10 of the power supply apparatus 100, the voltage difference between the second input 232 and the first input 231 of the comparing unit 23 is:

VREF-VGNDA1＝(V0+REFA)-(VGNDA+V1)＝V0+REFA-VGNDA-V1＝V0-V1

that is, in the present embodiment, the control switch S3 is the same as the second switch S2, the zener diode D2 is the same as the zener diode D1, and the second current source I2 is the same as the first current source I1, so that the first input 231 and the second input 232 of the comparator A1 have the same reference voltage in the power supply apparatus 100a. In this way, when the voltage of the power supply VBUS varies, it is possible to detect whether the corresponding interface 10 is inserted into the charging apparatus 200 by comparing the voltage generated when the charging apparatus 200 is inserted with the voltage of the reference voltage source V0 without adjusting the reference voltage.

It is understood that the voltage value of the reference voltage source V0 is a load voltage threshold value when the interface 10 is connected to the charging device 200. In this way, whether the voltage of the power supply VBUS is a high voltage or a low voltage, it can be determined whether the interface 10 is connected to the charging apparatus 200 only by setting the voltage value of the reference voltage source V0.

It is understood that, in the present embodiment, the operation principle of the power supply device 100a is as follows:

when the charging device 200 is not connected to all the interfaces 10 of the power supply apparatus 100a, each interface 10 is disconnected from the first current source I1, so that the voltage of the first input terminal 231 is 0V. Since the second input terminal 232 is also connected to the reference voltage source V0, the voltage of the first input terminal 231 is smaller than the reference voltage of the second input terminal 232, so the output terminal 233 outputs the control signal Vout, and the control signal Vout is at the second level. In this way, the control signal Vout controls the first switch S1 to maintain an off state, and controls the second switch S2 and the control switch S3 to maintain an on state.

When the charging apparatus 200 is connected to the power supply device 100a, the power supply VBUS, the interface 10 to which the charging apparatus 200 is connected, and the first current source I1 form a circuit loop. In this way, the voltage across the first current source I1 rises, so that the voltage at the first input terminal 231 of the comparator A1 is greater than the reference voltage at the second input terminal 232, the output terminal 233 of the comparator A1 outputs the control signal Vout, and the control signal Vout is at the first level. In this way, the control signal Vout controls the first switch S1 to maintain the on state, and controls the second switch S2 and the control switch S3 to maintain the off state. At this time, the voltage across the interface 10 is no longer limited, and the interface 10 can perform fast charging on the charging device 200 using a high voltage. That is, the detection unit 21 and the comparison unit 23 jointly detect that the interface 10 is inserted into the charging apparatus 200. The power supply VBUS may further adjust an output voltage correspondingly, so as to perform high-voltage fast charging on the charging device 200.

It can be understood that, since the plurality of interfaces 10 on the power supply apparatus 100a are connected in parallel with each other, both ends of the other interfaces 10 on the power supply apparatus 100a to which the charging device 200 is not connected have the same voltage as both ends of the interface 10 to which the charging device 200 is connected. The voltage across the first current source I1 is smaller than the reference voltage, that is, the voltage at the first input terminal 231 is smaller than the reference voltage at the second input terminal 232, so that the output terminal 233 of the comparator A1 outputs the control signal Vout, and the control signal Vout is at the second level. The control signal Vout controls the first switch S1 to keep an off state, and controls the second switch S2 and the control switch S3 to keep an on state.

Since the second switch S2 and the zener diode D1 are connected in series at two ends of the interface 10, and the second switch S2 is turned on, the voltage at two ends of the interface 10 is limited to the breakdown voltage of the zener diode D1, for example, 5V. In this way, the voltage across the interface 10 to which the charging apparatus 200 is not connected can be limited to a safer voltage range.

It can be understood that, in this embodiment, by replacing the detection element 211 with the first current source I1, and further inserting the charging device 200 into the interface 10, the current flowing through the first current source I1 is limited to the current value flowing out from the first current source I1, so as to prevent the electronic components in the power supply device 100a from being damaged due to the excessive instantaneous current, and improve the comparison accuracy of the comparison unit 23.

It can be understood that, in the embodiment, the power supply apparatus 100a replaces the reference voltage at the second input end 232 with a circuit composed of a control switch S3, a zener diode D2, a second current source I2 and a reference voltage source V0, so that the voltage VREF at the second input end 232 of the comparing unit 23 can automatically change with the change of the voltage across the first current source I1, and thus the comparing unit 23 can also work normally when the voltage of the power supply VBUS changes.

Referring to fig. 5, the present invention further provides a power supply apparatus 100b. The circuit configuration of the power feeding device 100b is substantially the same as that of the power feeding device 100a. The difference is that the circuit configuration of the control module 20b of the power supply apparatus 100b is different from the circuit configuration of the control module 20a of the power supply apparatus 100a.

In the present embodiment, the circuit structure of the control module 20b is substantially the same as that of the control module 20a, and the differences mainly lie in: the control module 20b includes a detection unit 21b, the voltage limiting unit 22 and a comparison unit 23b. The detection unit 21b includes the first switch S1 and a detection element 211b. The detecting element 211b is a first reference switch S4. The comparing unit 23b includes a first comparing switch S5, a second comparing switch S7, a third reference switch S8, and a second resistor R2. The power supply apparatus 100b further includes a reference voltage unit 234b. The reference voltage unit 234b is used for providing a reference voltage for the comparison unit 23b. The reference voltage unit 234b includes the control switch S3, the voltage regulator 221b, and a second reference switch S6.

The first switch S1, the first reference switch S4, the first comparison switch S5, the second reference switch S6, and the third reference switch S8 are NMOS transistors, and the second switch S2, the control switch S3, and the second comparison switch S7 are PMOS transistors.

The first terminal S11 of the first switch S1, the first terminal S41 of the first reference switch S4, the first terminal S51 of the first comparison switch S5, the first terminal S61 of the second reference switch S6, and the first terminal S81 of the third reference switch S8 are all drains. The second terminal S12 of the first switch S1, the second terminal S42 of the first reference switch S4, the second terminal S52 of the first comparison switch S5, the second terminal S62 of the second reference switch S6, and the second terminal S82 of the third reference switch S8 are all sources. The third terminal S13 of the first switch S1, the third terminal S43 of the first reference switch S4, the third terminal S53 of the first comparison switch S5, the third terminal S63 of the second reference switch S6, and the third terminal S83 of the third reference switch S8 are all gates.

The first end S21 of the second switch S2, the first end S31 of the control switch S3, and the first end S71 of the second comparison switch S7 are all sources. The second terminal S22 of the second switch S2, the second terminal S32 of the control switch S3, and the second terminal S72 of the second comparison switch S7 are all drains, and the third terminal S23 of the second switch S2, the third terminal S33 of the control switch S3, and the third terminal S73 of the second comparison switch S7 are all gates.

In this embodiment, the voltage regulator 221b is also the voltage regulator diode D2.

The connection relationship between the first end S11 and the second end S12 of the first switch S1, the first end S21 and the second end S22 of the second switch S2, and the zener diode D1 is the same as the connection relationship between the first switch S1 and the second switch S2 in the power supply device 100a, and is not described herein again.

A first terminal S31 of the control switch S3 is electrically connected between the power supply source VBUS and the first terminal S21 of the second switch S2, and a second terminal S32 of the control switch S3 is electrically connected to the cathode of the zener diode D2. The third terminal S33 of the control switch S3 is used for receiving the control signal Vout.

The first terminal S41 of the first reference switch S4 is electrically connected between the ground pin GND of the interface 10 and the first terminal S11 of the first switch S1, the second terminal S42 of the first reference switch S4 is grounded, and the third terminal S43 of the first reference switch S4 is electrically connected to the first reference current source VB1.

A first terminal S31 of the control switch S3 is electrically connected between the power supply source VBUS and the first terminal S21 of the second switch S2, a second terminal S32 of the control switch S3 is electrically connected to a cathode of the zener diode D2, and an anode of the zener diode D2 is electrically connected to a second terminal S52 of the first comparison switch S5.

One end of the second resistor R2 is electrically connected between the power supply VBUS and the first end S31 of the control switch S3, and the other end of the second resistor R2 is electrically connected to the first end S51 of the first comparison switch S5. The second terminal S52 of the first comparison switch S5 is electrically connected to the first terminal S61 of the second reference switch S6. The third terminal S53 of the first comparison switch S5 is electrically connected between the anode of the zener diode D1 and the first terminal S41 of the first reference switch S4, i.e., the third terminal S53 of the first comparison switch S5 is electrically connected between the ground pin GND of the interface 10 and the first terminal S11 of the first switch S1. The second terminal S62 of the second reference switch S6 is grounded, the third terminal S63 of the second reference switch S6 is electrically connected to a second reference current source VB2, the first terminal S71 of the second comparison switch S7 is electrically connected between the power supply VBUS and the second resistor R2, the second terminal S72 of the second comparison switch S7 is electrically connected to the first terminal S81 of the third reference switch S8, the third terminal S83 of the second comparison switch S8 is electrically connected between the second resistor R2 and the first comparison switch S5, the second terminal S82 of the third reference switch S8 is grounded, the third terminal S83 of the third reference switch S8 is electrically connected to a third reference current source VB3, and the second terminal S72 of the second comparison switch S7 and the first terminal S81 of the third reference switch S8 are configured to output the control signal Vout together.

In this embodiment, the first reference current source VB1, the second reference current source VB2 and the third reference current source VB3 output currents with the same magnitude and direction for providing bias currents for the first reference switch S4, the second reference switch S6 and the third reference switch S8, respectively, so that the first reference switch S4, the second reference switch S6 and the third reference switch S8 form a current mirror.

It is understood that the operation principle of the power supply device 100b is substantially the same as the operation principle of the power supply device 100a and the power supply device 100b, and the detailed description thereof is omitted.

It is understood that, in the interface 10 to which the charging device 200 is connected to the power supply apparatus 100a, the first reference switch S4, the first comparison switch S5, the second reference switch S6, and the second comparison switch S7 in the corresponding control module 20 are turned on. In this way, the second terminal S72 of the second comparison switch S7 and the first terminal S81 of the third reference switch S8 output the control signal Vout together, and the control signal Vout is at the first level, so that the control signal Vout controls the first switch S1 to keep the on state, and controls the second switch S2 and the control switch S3 to keep the off state.

In the other interface 10 of the power supply device 100a to which the charging equipment 200 is not connected, the first comparison switch S5 and the second comparison switch S7 in the corresponding control module 20 are turned off, and the first reference switch S4, the second reference switch S6, and the third reference switch S8 are turned on. In this way, the second terminal S72 of the second comparison switch S7 and the first terminal S81 of the eighth comparison switch S8 output the control signal Vout together, and the control signal Vout is at the second level, so that the control signal Vout controls the first switch S1 to keep the off state, and controls the second switch S2 and the control switch S3 to keep the on state. In this way, the voltage across the interface 10 to which the charging device 200 is not connected can be limited to the breakdown voltage of the first zener diode D1 or to the voltage of the power supply source VBUS.

It is understood that the power supply device 100 may be a multi-port mobile power supply or a multi-port adapter, etc.

It is to be understood that, in other embodiments, the first switch S1 to the third reference switch S8 may also be other switch circuits or electronic components with switch functions, and the types of the first electronic switch S1 to the third reference switch S8 are not limited in the present invention.

It is understood that the control module 20 may be integrated into a charging protocol chip (not shown).

It can be understood that, according to the present invention, the control modules 20/20a/20b are disposed at the two ends of the interface 10, and each control module includes the detection unit 21, the voltage limiting unit 22 and the comparison unit 23/23b, and when the detection unit 21 and the comparison unit 23 determine that the interface is inserted into the charging device 200, the voltages at the two ends of the other interfaces 10, which are not connected to the charging device 200, on the same power supply apparatus 100 are limited within a safe voltage range, so as to prevent the interface 10 of the power supply apparatus 100 having multiple ports from generating a large voltage, and reduce the safety risk when the interface 10 is connected to other charging devices 200.

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and are not limited. It should be understood by those skilled in the art that various modifications and equivalents may be made to the present invention without departing from the spirit and scope of the invention. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, shall fall within the protection scope of the present invention.

Claims

1. A power supply apparatus for connecting a plurality of charging devices, the power supply apparatus comprising:

a power supply;

at least two interfaces;

the control modules are connected with the interfaces in a one-to-one corresponding mode, each control module comprises a detection unit, a voltage limiting unit and a comparison unit, each detection unit comprises a first switch and a detection element, each voltage limiting unit comprises a second switch and a voltage limiting element, each voltage limiting element is a voltage stabilizing diode, the cathode of each voltage stabilizing diode is electrically connected to the second switch, and the anode of each voltage stabilizing diode is electrically connected between the interface and the first switch;

2. The power supply device according to claim 1, wherein: when the control signal is at a first level, the control signal controls the first switch to be switched on and controls the second switch to be switched off; when the control signal is at a second level, the control signal controls the first switch to be turned off and controls the second switch to be turned on.

3. The power supply device according to claim 1, wherein: the first switch is an NMOS tube, and the second switch is a PMOS tube.

4. The power supply device according to claim 1, wherein: the detection element is a first resistor, a first current source or a first reference switch.

5. The power supply device according to claim 4, wherein: the comparison unit comprises a comparator, the comparator comprises a first input end, a second input end and an output end, the first input end of the comparator is electrically connected between the first switch and the interface, the second input end of the comparator is used for receiving a reference voltage, and the output end of the comparator is used for outputting the control signal.

6. The power supply device according to claim 5, wherein: the power supply device further comprises a reference voltage unit for providing the reference voltage for the second input terminal.

7. The power supply device according to claim 6, wherein: the reference voltage unit comprises a control switch, a voltage stabilizing element, a second current source and a reference voltage source, wherein one end of the control switch is electrically connected between the power supply and the first switch, the other end of the control switch is electrically connected to one end of the voltage stabilizing element, the other end of the voltage stabilizing element is electrically connected to the input end of the second current source, the output end of the second current source is grounded, the negative pole of the reference voltage source is electrically connected between the voltage stabilizing element and the second current source, and the positive pole of the reference voltage source is electrically connected to the second input end.

8. The power supply device according to claim 6, wherein: the reference voltage unit comprises a control switch, a voltage stabilizing element and a second reference switch;

the comparison unit comprises a second resistor, a first comparison switch, a second comparison switch and a third reference switch;

a first terminal of the first reference switch is electrically connected between the interface and the first switch, a second terminal of the first reference switch is grounded, and a third terminal of the first reference switch is electrically connected to a first reference current source;

a first end of the control switch is electrically connected between the power supply and the second switch, a second end of the control switch is electrically connected to a cathode of the voltage stabilizing element, and an anode of the voltage stabilizing element is electrically connected to a second end of the first comparison switch;

one end of the second resistor is electrically connected between the power supply and the control switch, the other end of the second resistor is electrically connected to a first end of the first comparison switch, a second end of the first comparison switch is electrically connected to a first end of the second reference switch, a third end of the first comparison switch is electrically connected between the interface and the first switch, a second end of the second reference switch is grounded, a third end of the second reference switch is electrically connected to a second reference current source, a first end of the second comparison switch is electrically connected between the power supply and the second resistor, a second end of the second comparison switch is electrically connected to a first end of the third reference switch, a third end of the second comparison switch is electrically connected between the second resistor and the first comparison switch, a second end of the third reference switch is grounded, a third end of the third reference switch is electrically connected to a third reference current source, and the second end of the second comparison switch and the first end of the third reference switch are used for outputting the control signal together.

9. The power supply device according to claim 8, wherein: the control switch is a PMOS tube, the first reference switch, the second reference switch, the first comparison switch and the third reference switch are NMOS tubes, and the second comparison switch is a PMOS tube.