Multi-channel USB charging anti-backflow circuit

Abstract

The invention, which relates to the technical field of USB charging, discloses a multi-channel USB charging anti-backflow circuit comprising a USB charging module which cooperates with a first output module and a second output module to carry out double-channel electric energy conversion adjustment processing and charging control, and an output protection module carries out anti-reverse connection protection and secondary anti-backflow protection processing on the first output module. The electric energy detection module transmits the electric energy input into the second output module to the first output module according to the detected power supply state of the USB charging module when the power supply of the USB charging module is abnormal and the output protection module carries out anti-backflow protection, and the charging state of the first output module is maintained. In addition, the anti-backflow capability of the first output module can be detected through the protection detection module, and the output protection module is automatically controlled to perform anti-backflow protection processing when anti-backflow abnormity occurs. According to the multi-channel USB charging anti-backflow circuit, the charging efficiency can be improved, and the anti-backflow capability and the circuit safety of the circuit are improved.

Description

Technical Field

[0001] This invention relates to the field of USB charging technology, specifically a multi-channel USB charging anti-reverse current circuit. Background Technology

[0002] A multi-channel USB charging circuit integrates multiple (two or more) independent USB charging ports and corresponding power management circuits, enabling simultaneous charging control for multiple (two or more) devices. To prevent reverse power flow, a reverse power protection circuit composed of diodes or relays is used. In the event of reverse power flow, the rechargeable battery connected to the USB charging port is disconnected. However, if this reverse power protection circuit malfunctions, such as diode breakdown or relay failure, it will not be able to perform reverse power protection properly. The safety factor of the multi-channel USB charging circuit is relatively low, and a failure in the power management circuit will also lead to abnormal USB charging and reduced charging efficiency. Therefore, improvements are needed. Summary of the Invention

[0003] This invention provides a multi-channel USB charging anti-reverse current circuit to solve the problems mentioned in the background art.

[0004] According to an embodiment of the present invention, a multi-channel USB charging anti-reverse current circuit is provided, comprising: a USB charging module connected to a first output module, used to receive AC power and perform dual-channel transformation, rectification, voltage regulation and filtering, and output first power and second power respectively, and transmit the second power to the first output module; The power detection module is connected to the USB charging module and the output protection module. It is used to step down, rectify and divide AC power and output a first detection signal, divide the first power and output a second detection signal, and when the first detection signal is output, the second detection signal is not output and the first protection signal is received from the output protection module, it performs high-level self-locking and controls the USB charging module to transmit the second power. The first output module is used to perform unidirectional power transmission and transmit the received first or second power to the connected battery device. The second output module is connected to the USB charging module and is used to perform unidirectional power transmission and transmit the second power to the connected battery device. The protection detection module is connected to the first output module and the USB charging module. It is used to process the voltage drop of the first power and detect the voltage difference between the processed power and the first power transmitted unidirectionally by the first output module. When the detected voltage difference is greater than the set voltage difference threshold, a second protection signal is output. The output protection module is connected to the USB charging module, the first output module, and the protection detection module. It is used to perform reverse connection detection and reverse power supply detection on the battery device connected to the first output module, and to control the first output module to disconnect from the USB charging module when the reverse connection or reverse power supply of the battery device is detected or the second protection signal is received.

[0005] As a further embodiment of the present invention: the USB charging module includes a power port, a first power supply device, a second power supply device, a first capacitor, and a second capacitor. Preferably, the first end of the power port is connected to the first input terminal of the first power supply device and the first input terminal of the second power supply device, the second end of the power port is connected to the second input terminal of the first power supply device and the second input terminal of the second power supply device, the first output terminal of the first power supply device is connected to the protection detection module and connected to the second output terminal of the first power supply device through the first capacitor, and the first output terminal of the second power supply device is connected to the second output terminal of the second power supply device through the second capacitor.

[0006] As a further embodiment of the present invention: the USB charging module further includes a first thyristor, a fifth diode, and a first power transistor; the first output module includes a third diode and a first port; the second output module includes a fourth diode and a second port; Preferably, the anode of the fifth diode is connected to the anode of the fourth diode and the first output terminal of the second power supply device; the cathode of the fifth diode is connected to the drain of the first power transistor; the cathode of the fourth diode is connected to the first terminal of the second port; the second terminal of the second port is connected to the second output terminal of the second power supply device and the cathode of the first thyristor; the source of the first power transistor is connected to the first terminal of the first port and the cathode of the third diode; the anode of the third diode is connected to the first output terminal of the first power supply device; the anode of the first thyristor is connected to the second output terminal of the first power supply device; and the control terminal of the first thyristor is connected to the gate of the first power transistor. As a further embodiment of the present invention: the power detection module includes a fourth capacitor, a first resistor, a first rectifier, a second resistor, a third resistor, a first inverter, a fourth resistor, a fifth resistor, a first logic device, a second logic device, a first diode, and a second diode; Preferably, one end of the fourth capacitor is connected to the first end of the power supply port and the other end of the fourth capacitor is connected to the first input terminal of the first rectifier through the first resistor. The second input terminal of the first rectifier is connected to the second end of the power supply port. The first output terminal of the first rectifier is connected to one end of the third resistor and the B terminal of the first logic device through the second resistor. The other end of the third resistor is connected to the second output terminal of the first rectifier. The A terminal of the first logic device is connected to the output terminal of the first inverter. The input terminal of the first inverter is connected to one end of the fifth resistor and the first output terminal of the first power supply device through the fourth resistor. The other end of the fifth resistor is connected to the second output terminal of the first power supply device. The Y terminal of the first logic device is connected to the A terminal of the second logic device. The B terminal of the second logic device is connected to the cathode of the second diode and the cathode of the first diode. The Y terminal of the second logic device is connected to the anode of the first diode and the gate of the first power transistor.

[0007] As a further embodiment of the present invention: the output protection module includes a seventh resistor, a second switching transistor, a sixth resistor, a sixteenth resistor, a sixth diode, and a second power transistor; Preferably, the emitter of the second switching transistor is connected to the cathode of the third diode, the collector of the second switching transistor is connected to the cathode of the sixth diode, the gate of the second power transistor and one end of the seventh resistor through the sixth resistor, the other end of the seventh resistor is connected to the source of the second power transistor, the anode of the sixth diode and the second output terminal of the first power supply device, and the drain of the second power transistor is connected to the second end of the first port and connected to the base of the second switching transistor through the sixteenth resistor.

[0008] As a further embodiment of the present invention: the output protection module further includes an eighth resistor, a ninth resistor, a first operational amplifier, a tenth resistor, a third capacitor, a seventh diode, and a first switching transistor; Preferably, one end of the eighth resistor is connected to the second end of the first port, the other end of the eighth resistor is connected to the inverting input of the first operational amplifier and one end of the tenth resistor, and is connected to the other end of the tenth resistor and the output terminal of the first operational amplifier, the anode of the seventh diode and the anode of the second diode through the third capacitor, the non-inverting input of the first operational amplifier is connected to the anode of the sixth diode and the emitter of the first switching transistor through the ninth resistor, the cathode of the seventh diode is connected to the base of the first switching transistor and the protection detection module, and the collector of the first switching transistor is connected to the cathode of the sixth diode.

[0009] As a further embodiment of the present invention: the protection detection module includes an eighth diode, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a second operational amplifier, a fifteenth resistor, a ninth diode, and a tenth diode; Preferably, the anode of the eighth diode is connected to the anode of the third diode, the cathode of the eighth diode is connected to the inverting input of the second operational amplifier and one end of the fourteenth resistor through the eleventh resistor, the other end of the fourteenth resistor is connected to the output terminal of the second operational amplifier and is connected to the cathode of the ninth diode through the fifteenth resistor, the anode of the ninth diode is connected to the anode of the tenth diode, the cathode of the tenth diode is connected to the base of the first switching transistor, the non-inverting input of the second operational amplifier is connected to one end of the twelfth resistor and is grounded through the thirteenth resistor, and the other end of the twelfth resistor is connected to the cathode of the third diode.

[0010] Compared with the prior art, the beneficial effects of the present invention are as follows: The multi-channel USB charging anti-reverse current circuit of the present invention can use a USB charging module in conjunction with a first output module and a second output module to perform dual-channel power conversion and regulation processing and to control the charging of connected battery devices. Both the first output module and the second output module have anti-reverse current capability. At the same time, the output protection module provides anti-reverse connection protection and secondary anti-reverse current protection processing for the first output module. The power detection module, based on the detected power supply status of the USB charging module, transfers the power input to the second output module to the first output module when the power supply of the USB charging module is abnormal and the output protection module performs anti-reverse current protection, thereby maintaining the charging status of the first output module and improving charging efficiency. The protection detection module can also detect the anti-reverse current capability of the first output module and automatically control the output protection module to perform anti-reverse current protection processing when an anti-reverse current abnormality occurs, thereby improving the anti-reverse current capability and circuit safety of the circuit. Attached Figure Description

[0011] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is a schematic block diagram of a multi-channel USB charging anti-reverse current circuit provided in an embodiment of the present invention.

[0013] Figure 2 The circuit diagram is provided for a multi-channel USB charging anti-reverse current circuit according to an embodiment of the present invention.

[0014] Figure 3 The circuit diagram of the protection detection module provided in the embodiment of the present invention. Detailed Implementation

[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] Please see Figure 1 A multi-channel USB charging anti-reverse current circuit includes: USB charging module 1 is connected to the first output module 3. It is used to receive AC power and perform dual-channel transformation, rectification, voltage regulation and filtering, and output the first power and the second power respectively, and transmit the second power to the first output module 3. The power detection module 2 is connected to the USB charging module 1 and the output protection module 6. It is used to step down, rectify and divide the AC power and output a first detection signal, divide the first power and output a second detection signal, and when the first detection signal is output, the second detection signal is not output and the first protection signal is received from the output protection module 6, it performs high-level self-locking and controls the USB charging module 1 to transmit the second power. The first output module 3 is used to perform unidirectional power transmission and transmit the received first or second power to the connected battery device. The second output module 4 is connected to the USB charging module 1 and is used to perform unidirectional power transmission and transmit the second power to the connected battery device. The protection detection module 5 is connected to the first output module 3 and the USB charging module 1. It is used to perform voltage drop processing on the first power and to detect the voltage difference between the processed power and the first power transmitted unidirectionally by the first output module 3. When the detected voltage difference is greater than the set voltage difference threshold, it outputs a second protection signal. The output protection module 6 is connected to the USB charging module 1, the first output module 3 and the protection detection module 5. It is used to perform reverse connection detection and reverse power supply detection on the battery device connected to the first output module 3, and to control the first output module 3 to disconnect from the USB charging module 1 when the reverse connection or reverse power supply of the battery device is detected or the second protection signal is received.

[0017] In a specific embodiment, the USB charging module 1 can be a USB charging circuit composed of a power port, a power supply device, and capacitors. It can accept AC power and perform dual-path transformation, rectification, voltage regulation, and filtering on the AC power to obtain a first power and a second power, wherein the voltage of the first power is equal to the voltage of the second power. The power detection module 2 can be a power detection circuit composed of resistors, capacitors, rectifiers, and logic devices. It can perform voltage reduction, rectification, and voltage division on the AC power, perform voltage division on the first power, perform logical calculations on the processed signals, and when the USB charging module 1 accepts AC power but does not output the first power and the output protection module 6 performs anti-reverse current protection, it performs high-level self-locking and controls the USB charging module 1 to transmit the second power to the first output module 3. The first output module 3 can be composed of diodes and output terminals. The first output circuit, composed of a diode and an output port, controls the unidirectional transmission of electrical energy and supplies power to the connected battery device. The second output module 4 can be a second output circuit composed of a diode and an output port, controlling the unidirectional transmission of electrical energy and supplying power to the connected battery device. The protection and detection module 5 can be a protection and detection circuit composed of a resistor, a diode, and an operational amplifier. It can process the voltage drop of the first electrical energy output by the USB charging module 1 and subtract it from the unidirectional electrical energy transmitted by the first output module 3. The calculated signal is compared with a set voltage difference threshold, which is the voltage drop of the diode. The output protection module 6 can be an output protection circuit composed of a transistor, a resistor, a field-effect transistor, an operational amplifier, etc. It can perform reverse connection power-off protection or reverse charging power-off protection according to the positive and negative polarity of the battery device connected to the first output module 3.

[0018] In this embodiment, please refer to Figure 2 and Figure 3 The USB charging module 1 includes a power port, a first power supply device, a second power supply device, a first capacitor C1, and a second capacitor C2. Specifically, the first end of the power port is connected to the first input terminal of the first power supply device and the first input terminal of the second power supply device, the second end of the power port is connected to the second input terminal of the first power supply device and the second input terminal of the second power supply device, the first output terminal of the first power supply device is connected to the protection detection module 5 and connected to the second output terminal of the first power supply device through the first capacitor C1, and the first output terminal of the second power supply device is connected to the second output terminal of the second power supply device through the second capacitor C2.

[0019] In a specific embodiment, both the first power supply device and the second power supply device can be composed of a transformer, a rectifier, and a voltage regulator.

[0020] Furthermore, the USB charging module 1 also includes a first thyristor S1, a fifth diode D5, and a first power transistor Q1; the first output module 3 includes a third diode D3 and a first port; the second output module 4 includes a fourth diode D4 and a second port; Specifically, the anode of the fifth diode D5 is connected to the anode of the fourth diode D4 and the first output terminal of the second power supply device; the cathode of the fifth diode D5 is connected to the drain of the first power transistor Q1; the cathode of the fourth diode D4 is connected to the first terminal of the second port; the second terminal of the second port is connected to the second output terminal of the second power supply device and the cathode of the first thyristor S1; the source of the first power transistor Q1 is connected to the first terminal of the first port and the cathode of the third diode D3; the anode of the third diode D3 is connected to the first output terminal of the first power supply device; the anode of the first thyristor S1 is connected to the second output terminal of the first power supply device; and the control terminal of the first thyristor S1 is connected to the gate of the first power transistor Q1.

[0021] In a specific embodiment, the first power transistor Q1 can be an N-channel MOSFET; the third diode D3 and the fourth diode D4 are both used for unidirectional power transmission and anti-reverse current protection control; and the first thyristor S1 can be a unidirectional thyristor.

[0022] Furthermore, the power detection module 2 includes a fourth capacitor C4, a first resistor R1, a first rectifier T1, a second resistor R2, a third resistor R3, a first inverter INV1, a fourth resistor R4, a fifth resistor R5, a first logic device J1, a second logic device J2, a first diode D1, and a second diode D2. Specifically, one end of the fourth capacitor C4 is connected to the first terminal of the power supply port and the other end of the fourth capacitor C4 is connected to the first input terminal of the first rectifier T1 through the first resistor R1. The second input terminal of the first rectifier T1 is connected to the second terminal of the power supply port. The first output terminal of the first rectifier T1 is connected to one end of the third resistor R3 and the B terminal of the first logic device J1 through the second resistor R2. The other end of the third resistor R3 is connected to the second output terminal of the first rectifier T1. The A terminal of the first logic device J1 is connected to the output terminal of the first inverter INV1. The input terminal of the first inverter INV1 is connected to one end of the fifth resistor R5 and the first output terminal of the first power supply device through the fourth resistor R4. The other end of the fifth resistor R5 is connected to the second output terminal of the first power supply device. The Y terminal of the first logic device J1 is connected to the A terminal of the second logic device J2. The B terminal of the second logic device J2 is connected to the cathode of the second diode D2 and the cathode of the first diode D1. The Y terminal of the second logic device J2 is connected to the anode of the first diode D1 and the gate of the first power transistor Q1.

[0023] In a specific embodiment, the first capacitor C1 and the first resistor R1 are subjected to voltage drop processing; the first logic device J1 and the second logic device J2 can both be AND gates, wherein the second logic device J2, together with the first diode D1 and the second diode D2, can perform high-level self-locking; the first inverter INV1 can be a NOT gate.

[0024] Furthermore, the output protection module 6 includes a seventh resistor R7, a second switch V2, a sixth resistor R6, a sixteenth resistor R16, a sixth diode D6, and a second power transistor Q2; Specifically, the emitter of the second switch V2 is connected to the cathode of the third diode D3. The collector of the second switch V2 is connected to the cathode of the sixth diode D6, the gate of the second power transistor Q2, and one end of the seventh resistor R7 through the sixth resistor R6. The other end of the seventh resistor R7 is connected to the source of the second power transistor Q2, the anode of the sixth diode D6, and the second output terminal of the first power supply device. The drain of the second power transistor Q2 is connected to the second terminal of the first port and is connected to the base of the second switch V2 through the sixteenth resistor R16.

[0025] In a specific embodiment, the second switching transistor V2 can be a PNP transistor; the second power transistor Q2 can be an N-channel MOSFET.

[0026] Furthermore, the output protection module 6 also includes an eighth resistor R8, a ninth resistor R9, a first operational amplifier OP1, a tenth resistor R10, a third capacitor C3, a seventh diode D7, and a first switching transistor V1; Specifically, one end of the eighth resistor R8 is connected to the second end of the first port, and the other end of the eighth resistor R8 is connected to the inverting input of the first operational amplifier OP1 and one end of the tenth resistor R10. Through the third capacitor C3, the other end of the tenth resistor R10 is connected to the output terminal of the first operational amplifier OP1, the anode of the seventh diode D7, and the anode of the second diode D2. The non-inverting input of the first operational amplifier OP1 is connected to the anode of the sixth diode D6 and the emitter of the first switching transistor V1 through the ninth resistor R9. The cathode of the seventh diode D7 is connected to the base of the first switching transistor V1 and the protection detection module 5. The collector of the first switching transistor V1 is connected to the cathode of the sixth diode D6.

[0027] In a specific embodiment, the first operational amplifier OP1 can be an LM358; the first switching transistor V1 can be an NPN transistor.

[0028] Furthermore, the protection detection module 5 includes an eighth diode D8, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14, a second operational amplifier OP2, a fifteenth resistor R15, a ninth diode D9, and a tenth diode D10; Specifically, the anode of the eighth diode D8 is connected to the anode of the third diode D3. The cathode of the eighth diode D8 is connected to the inverting input of the second operational amplifier OP2 and one end of the fourteenth resistor R14 through the eleventh resistor R11. The other end of the fourteenth resistor R14 is connected to the output of the second operational amplifier OP2 and is connected to the cathode of the ninth diode D9 through the fifteenth resistor R15. The anode of the ninth diode D9 is connected to the anode of the tenth diode D10. The cathode of the tenth diode D10 is connected to the base of the first switching transistor V1. The non-inverting input of the second operational amplifier OP2 is connected to one end of the twelfth resistor R12 and grounded through the thirteenth resistor R13. The other end of the twelfth resistor R12 is connected to the cathode of the third diode D3.

[0029] In a specific embodiment, the second operational amplifier OP2 can be selected as LM358; the fifteenth resistor R15 and the ninth diode D9 are used to set the voltage difference threshold.

[0030] In another embodiment, the protection detection module 5, the output protection module 6, and the power detection module 2 can also be applied to the second output module 4 to perform power detection, anti-reverse flow detection, reverse connection protection, and anti-reverse flow protection processing for the second output module 4. Furthermore, an output module with the same circuit structure as the second output module 4 can provide backup power for the second output module 4.

[0031] In this embodiment of a multi-channel USB charging anti-reverse current circuit, AC power is input through the power port. A first power supply device performs voltage transformation, rectification, and regulation to output first power, which is then filtered by a first capacitor C1. The first power is transmitted to the first port via a third diode D3. A second power supply device outputs second power, which is also filtered. The second power is transmitted to the second port via a fourth diode D4. The third and fourth diodes D3 and D4 provide simple anti-reverse current protection. The circuit is stepped down and rectified by a fourth capacitor C4, a first resistor R1, and a first rectifier T1, and then further rectified by a second resistor R2 and a third resistor R3. Voltage division is performed to output the first detection signal. Resistors R4 and R5 divide the first electrical energy and output the second detection signal. When the battery device connected to the first port is reversed, the second switch V2 is cut off, and the second power transistor Q2 will also be cut off. When the first port is normally connected to the battery device, but the power port is not connected to AC power or the first power supply device is not outputting the first electrical energy due to a fault, the second switch V2 is turned on. The electrical energy of the battery device will be transmitted to the non-inverting input of the first operational amplifier OP1 through resistors R6, R7, and R9, causing the first operational amplifier OP1 to output a high level. The first switching transistor V1 is triggered to turn on, controlling the second power transistor Q2 to turn off, performing reverse-current power-off protection. If the first power supply device fails to output the first power at this time due to a fault, the Y terminal of the first logic device J1 will output a high level, and the second logic device J2, in conjunction with the first diode D1 and the second diode D2, will self-lock and control the first power transistor Q1 and the first thyristor S1 to turn on, so that the second power is transmitted to the first port through the first power transistor Q1. At this time, the first port will be powered again, the reverse-current power disappears, and the output protection module 6 still performs reverse connection power-off protection and reverse-current power-off protection. At the same time, the eighth diode D8 controls the first power supply to turn on the first power supply to turn on the second ... The electrical energy undergoes voltage drop processing. The output voltage after the voltage drop is equal to the output voltage after the voltage drop of the third diode D3. The voltage drop is calculated by subtraction using the eleventh resistor R11, the twelfth resistor R12, the thirteenth resistor R13, the fourteenth resistor R14, and the second operational amplifier OP2. If the voltage drop of the third diode D3 is abnormal, the second operational amplifier OP2 will output a voltage difference. If this voltage difference is greater than the voltage difference threshold set by the fifteenth resistor R15 and the ninth diode D9, it indicates that the third diode D3 may be broken down. At this time, the first switching transistor V1 will be directly turned on, and the second power transistor Q2 will be turned off, stopping the power supply to the first port.

[0032] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims. Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A multi-channel USB charging anti-reverse current circuit, characterized in that, The circuit includes: The USB charging module is connected to the first output module and is used to receive AC power and perform dual-channel transformation, rectification, voltage regulation and filtering to output the first power and the second power respectively, and transmit the second power to the first output module. The power detection module is connected to the USB charging module and the output protection module. It is used to step down, rectify and divide AC power and output a first detection signal, divide the first power and output a second detection signal, and when the first detection signal is output, the second detection signal is not output and the first protection signal is received from the output protection module, it performs high-level self-locking and controls the USB charging module to transmit the second power. The first output module is used to perform unidirectional power transmission and transmit the received first or second power to the connected battery device. The second output module is connected to the USB charging module and is used to perform unidirectional power transmission and transmit the second power to the connected battery device. The protection detection module is connected to the first output module and the USB charging module. It is used to process the voltage drop of the first power and detect the voltage difference between the processed power and the first power transmitted unidirectionally by the first output module. When the detected voltage difference is greater than the set voltage difference threshold, a second protection signal is output. The output protection module is connected to the USB charging module, the first output module, and the protection detection module. It is used to perform reverse connection detection and reverse power supply detection on the battery device connected to the first output module, and to control the first output module to disconnect from the USB charging module when the reverse connection or reverse power supply of the battery device is detected or the second protection signal is received.

2. The multi-channel USB charging anti-reverse current circuit according to claim 1, characterized in that, The USB charging module includes a power port, a first power supply device, a second power supply device, a first capacitor, and a second capacitor. The first end of the power port is connected to the first input terminal of the first power supply device and the first input terminal of the second power supply device. The second end of the power port is connected to the second input terminal of the first power supply device and the second input terminal of the second power supply device. The first output terminal of the first power supply device is connected to the protection detection module and connected to the second output terminal of the first power supply device through the first capacitor. The first output terminal of the second power supply device is connected to the second output terminal of the second power supply device through the second capacitor.

3. The multi-channel USB charging anti-reverse current circuit according to claim 2, characterized in that, The USB charging module further includes a first thyristor, a fifth diode, and a first power transistor; the first output module includes a third diode and a first port; the second output module includes a fourth diode and a second port. The anode of the fifth diode is connected to the anode of the fourth diode and the first output terminal of the second power supply device. The cathode of the fifth diode is connected to the drain of the first power transistor. The cathode of the fourth diode is connected to the first terminal of the second port. The second terminal of the second port is connected to the second output terminal of the second power supply device and the cathode of the first thyristor. The source of the first power transistor is connected to the first terminal of the first port and the cathode of the third diode. The anode of the third diode is connected to the first output terminal of the first power supply device. The anode of the first thyristor is connected to the second output terminal of the first power supply device. The control terminal of the first thyristor is connected to the gate of the first power transistor.

4. The multi-channel USB charging anti-reverse current circuit according to claim 3, characterized in that, The power detection module includes a fourth capacitor, a first resistor, a first rectifier, a second resistor, a third resistor, a first inverter, a fourth resistor, a fifth resistor, a first logic unit, a second logic unit, a first diode, and a second diode. One end of the fourth capacitor is connected to the first end of the power supply port and the other end of the fourth capacitor is connected to the first input terminal of the first rectifier through the first resistor. The second input terminal of the first rectifier is connected to the second end of the power supply port. The first output terminal of the first rectifier is connected to one end of the third resistor and the B terminal of the first logic device through the second resistor. The other end of the third resistor is connected to the second output terminal of the first rectifier. The A terminal of the first logic device is connected to the output terminal of the first inverter. The input terminal of the first inverter is connected to one end of the fifth resistor and the first output terminal of the first power supply device through the fourth resistor. The other end of the fifth resistor is connected to the second output terminal of the first power supply device. The Y terminal of the first logic device is connected to the A terminal of the second logic device. The B terminal of the second logic device is connected to the cathode of the second diode and the cathode of the first diode. The Y terminal of the second logic device is connected to the anode of the first diode and the gate of the first power transistor.

5. A multi-channel USB charging anti-reverse current circuit according to claim 4, characterized in that, The output protection module includes a seventh resistor, a second switching transistor, a sixth resistor, a sixteenth resistor, a sixth diode, and a second power transistor; The emitter of the second switching transistor is connected to the cathode of the third diode. The collector of the second switching transistor is connected to the cathode of the sixth diode, the gate of the second power transistor, and one end of the seventh resistor through the sixth resistor. The other end of the seventh resistor is connected to the source of the second power transistor, the anode of the sixth diode, and the second output terminal of the first power supply device. The drain of the second power transistor is connected to the second end of the first port and is connected to the base of the second switching transistor through the sixteenth resistor.

6. The multi-channel USB charging anti-reverse current circuit according to claim 5, characterized in that, The output protection module also includes an eighth resistor, a ninth resistor, a first operational amplifier, a tenth resistor, a third capacitor, a seventh diode, and a first switching transistor; One end of the eighth resistor is connected to the second end of the first port. The other end of the eighth resistor is connected to the inverting input of the first operational amplifier and one end of the tenth resistor. It is also connected to the other end of the tenth resistor and the output of the first operational amplifier, the anode of the seventh diode, and the anode of the second diode through the third capacitor. The non-inverting input of the first operational amplifier is connected to the anode of the sixth diode and the emitter of the first switching transistor through the ninth resistor. The cathode of the seventh diode is connected to the base of the first switching transistor and the protection detection module. The collector of the first switching transistor is connected to the cathode of the sixth diode.

7. A multi-channel USB charging anti-reverse current circuit according to claim 6, characterized in that, The protection detection module includes an eighth diode, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a second operational amplifier, a fifteenth resistor, a ninth diode, and a tenth diode; The anode of the eighth diode is connected to the anode of the third diode. The cathode of the eighth diode is connected to the inverting input of the second operational amplifier and one end of the fourteenth resistor through the eleventh resistor. The other end of the fourteenth resistor is connected to the output of the second operational amplifier and is connected to the cathode of the ninth diode through the fifteenth resistor. The anode of the ninth diode is connected to the anode of the tenth diode. The cathode of the tenth diode is connected to the base of the first switching transistor. The non-inverting input of the second operational amplifier is connected to one end of the twelfth resistor and is grounded through the thirteenth resistor. The other end of the twelfth resistor is connected to the cathode of the third diode.

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