Multi-port charging circuit supporting portable equipment and switching power supply

Abstract

The invention provides a multi-port charging circuit supporting portable equipment and a switching power supply, and relates to the technical field of charging, the multi-port charging circuit comprises an electromagnetic compatibility module, a chip power supply module, a synchronous rectification module, a sampling feedback module, a protocol chip feedback module, an electrostatic discharge protection module, a first charging interface, a second charging interface, a transformer and a main control chip; the electromagnetic compatibility module, the chip power supply module, the sampling feedback module and the main control chip are arranged on the primary side of the transformer, the synchronous rectification module, the protocol chip feedback module and the electrostatic discharge protection module are arranged on the secondary side of the transformer, and the electromagnetic compatibility module is electrically connected with the primary side of the transformer through the primary side absorption module. The synchronous rectification module is electrically connected with a first charging interface and a second charging interface through the protocol chip feedback module and the electrostatic discharge protection module in sequence. According to the invention, a plurality of electronic devices with different charging port types can be charged at the same time, and more stable and safer charging is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of charging, and in particular, to a multi-port charging circuit and a switching power supply for supporting portable devices. Background Art

[0002] Currently, most electronic devices are powered by switching power supplies to save energy and improve work efficiency. With the popularization and application of portable electronic devices, in order to meet the charging requirements of more and more portable electronic devices, the chargers of these electronic devices are usually provided with multiple charging ports to facilitate charging multiple electronic devices simultaneously.

[0003] In the prior art, with the introduction of various charging interfaces, such as Type-A, Type-C, and USB-A interfaces, there have already been chargers with multiple interfaces. However, the output voltages of various charging interfaces may be different. It is very difficult to complete such a circuit design with only one transformer, which poses a safety hazard. If designed separately and independently, multiple transformers will be used, resulting in a relatively large overall volume of the charger.

[0004] Therefore, there is a need to provide a switching power supply with stable charging process, convenient to carry, and capable of multi-port charging. Summary of the Invention

[0005] In view of this, the present invention provides a multi-port charging circuit and a switching power supply for supporting portable devices to solve the problem of currently needing to provide a switching power supply with a more stable charging voltage and capable of multi-port charging.

[0006] The technical solution of the present invention is implemented as follows: According to a first aspect, an embodiment of the present invention provides a multi-port charging circuit for supporting portable devices, the circuit including: An electromagnetic compatibility module, a chip power supply module, a synchronous rectification module, a sampling feedback module, a protocol chip feedback module, an electrostatic discharge protection module, a first charging interface, a second charging interface, a transformer, and a main control chip; The electromagnetic compatibility module, the chip power supply module, the sampling feedback module, and the main control chip are arranged on the primary side of the transformer. The synchronous rectification module, the protocol chip feedback module, the electrostatic discharge protection module, the first charging interface, and the second charging interface are arranged on the secondary side of the transformer. The input voltage is electrically connected to the electromagnetic compatibility module. The electromagnetic compatibility module is electrically connected to the primary side of the transformer through the primary side absorption module. The synchronous rectification module is electrically connected to the secondary side of the transformer. The synchronous rectification module is electrically connected to the first charging interface and the second charging interface through the protocol chip feedback module and the electrostatic discharge protection module in sequence. The main control chip is electrically connected to the electromagnetic compatibility module. The main control chip performs sampling feedback from the output voltage through the sampling feedback module and the protocol chip feedback module. The sampling feedback module is electrically connected to the main control chip and the protocol chip feedback module.

[0007] Combined with the first aspect, in the first embodiment of the first aspect, the electromagnetic compatibility module in the circuit includes: Common mode inductor LF1, rectifier bridge BD1, differential mode inductor L1, differential mode inductor L2, polar capacitor EC1, and polar capacitor EC2; The second end and the third end of the common mode inductor LF1 are connected between the live wire and the neutral wire. The second end of the common mode inductor LF1 is electrically connected to the live wire, and the third end of the common mode inductor LF1 is electrically connected to the neutral wire. The first end and the fourth end of the common mode inductor LF1 are connected to the rectifier bridge BD1. The first end of the common mode inductor LF1 is electrically connected to the second end of the rectifier bridge BD1, and the fourth end of the common mode inductor LF1 is electrically connected to the third end of the rectifier bridge BD1. The first end of the rectifier bridge BD1 is electrically connected to the primary side absorption circuit through the series-connected differential mode inductor L1. The fourth end of the rectifier bridge BD1 is electrically connected to the primary side absorption circuit through the series-connected differential mode inductor L2. A parallel-connected polar capacitor EC1 and polar capacitor EC2 are electrically connected between the first end and the fourth end of the rectifier bridge BD1. The positive electrode of the polar capacitor EC1 is electrically connected between the first end of the rectifier bridge BD1 and the differential mode inductor L1, and the negative electrode of the polar capacitor EC1 is electrically connected between the fourth end of the rectifier bridge BD1 and the differential mode inductor L2. The positive electrode of the polar capacitor EC2 is electrically connected between the differential mode inductor L1 and the primary side absorption circuit, and the negative electrode of the polar capacitor EC2 is electrically connected between the differential mode inductor L2 and the primary side absorption circuit.

[0008] Combined with the first embodiment of the first aspect, in the second embodiment of the first aspect, a fuse F1 and a thermistor NTC1 are provided before the front end of the electromagnetic compatibility module; The fuse F1 is arranged on the live wire. One end of the fuse F1 is electrically connected to the live wire, and the other end of the fuse F1 is electrically connected to the second end of the common mode inductor L1. The thermistor NTC1 is arranged on the neutral wire. One end of the thermistor NTC1 is electrically connected to the neutral wire, and the other end of the thermistor NTC1 is electrically connected to the third end of the common mode inductor L1 Combined with the first embodiment of the first aspect, in the third embodiment of the first aspect, the chip power supply module in the circuit includes: Inductor L3, differential mode inductor T1B, diode D2, resistor R11, capacitor C8, resistor R10, and polarized capacitor EC3; The fifth pin of the main control chip U1 is grounded through the serially arranged inductor L3, resistor R10, diode D2, and differential mode inductor T1B. The fifth pin of the main control chip U1 is electrically connected to one end of the inductor L3. The other end of the inductor L3 is electrically connected to one end of the resistor R10. The other end of the resistor R10 is electrically connected to the negative electrode of the diode D2. The positive electrode of the diode D2 is electrically connected to one end of the differential mode inductor T1B. The other end of the differential mode inductor T1B is grounded. A serially arranged resistor R11 and capacitor C8 are connected in parallel between the positive and negative electrodes of the diode D2. One end of the resistor R11 is electrically connected to the positive electrode of the diode D2. The other end of the resistor R11 is electrically connected to one end of the capacitor C8. The other end of the capacitor C8 is electrically connected to the negative electrode of the diode D2. Between the inductor L3 and the resistor R10, it is electrically connected to the grounded end of the differential mode inductor T1B through the polarized capacitor EC3. The positive electrode of the polarized capacitor EC3 is electrically connected between the inductor L3 and the resistor R10. The negative electrode of the polarized capacitor EC3 is electrically connected to the grounded end of the differential mode inductor T1B.

[0009] Combined with the third embodiment of the first aspect, in the fourth embodiment of the first aspect, the sampling feedback module in the circuit includes: Resistors R4, R5, R6, R7, R8, R9, capacitors C3, C4, C5, C7, optocoupler U4B, and zener diode ZD1; The first pin of the main control chip U1 is electrically connected to one end of the differential mode inductor L2 that is far from the fourth end of the rectifier bridge BD1 through a series resistor R6. The ninth pin of the main control chip U1, i.e., the EPAD pin, is connected to the connection between the differential mode inductor L2 and the resistor R6 through the mutually parallel-connected resistors R4 and R5. One end of the resistor R4 and the resistor R5 is electrically connected to the ninth pin of the main control chip U1, and the other end of the resistor R4 and the resistor R5 is connected to the connection between the differential mode inductor L2 and the resistor R6. The second pin of the main control chip U1 is electrically connected to the optocoupler U4B and the zener diode ZD1 through a resistor R7. One end of the resistor R7 is electrically connected to the second pin of the main control chip U1, and the other end of the resistor R7 is respectively electrically connected to the input end of the receiver of the optocoupler U4B and the negative electrode of the zener diode ZD1. The output end of the receiver of the optocoupler U4B and the positive electrode of the zener diode ZD1 are grounded. The second pin of the main control chip U1 is grounded through a series capacitor C4. One end of the capacitor C4 is electrically connected to the second pin of the main control chip U1, and the other end of the capacitor C4 is grounded. The third pin of the main control chip U1 is grounded through the mutually parallel-connected resistor R9 and capacitor C7. One end of the resistor R9 and the capacitor C7 is electrically connected to the third pin of the main control chip U1, and the other end of the resistor R9 and the capacitor C7 is grounded. The third pin of the main control chip U1 is electrically connected to one end where the differential mode inductor T1B is connected to the diode D2 through a resistor R8. The fourth pin of the main control chip U1 is grounded through a capacitor C5. One end of the capacitor C5 is electrically connected to the fourth pin of the main control chip U1, and the other end of the capacitor C5 is grounded.

[0010] Combined with the fourth embodiment of the first aspect, in the fifth embodiment of the first aspect, the primary side absorption module in the circuit includes: Capacitor C2, resistor R2, resistor R3, and diode D1; The third end of the primary side of the transformer T1 is connected to the positive electrode of the diode D1. The negative electrode of the diode D1 is electrically connected to one end of the resistor R3. The other end of the resistor R3 is electrically connected to the connection between the differential mode inductor L1 and the fourth end of the primary side of the transformer T1 through the mutually parallel-connected resistor R2 and capacitor C2.

[0011] 7. The multi-port charging circuit for supporting portable devices according to claim 6, wherein: the synchronous rectification module 300 in the circuit includes: Rectification chip U2, capacitor C9, capacitor C10, and resistor R12; The first pin, the fifth pin, the fifth pin, the seventh pin, and the eighth pin of the rectifier chip U2 are all electrically connected to the seventh end of the secondary side of the transformer T1. The third pin and the fourth pin of the rectifier chip U2 are both electrically connected to the seventh end of the secondary side of the transformer T1 through the serially arranged capacitor C10 and resistor R12. One end of the resistor R12 is electrically connected to the seventh end of the secondary side of the transformer T1, the other end of the resistor R12 is electrically connected to one end of the capacitor C10, and the other end of the capacitor C10 is electrically connected to the third pin and the fourth pin of the rectifier chip U2. The second pin of the rectifier chip U2, i.e., the GND pin, is electrically connected to the end of the capacitor C10 away from the resistor R12 through the capacitor C9.

[0012] Combined with the sixth embodiment of the first aspect, in the seventh embodiment of the first aspect, the protocol chip feedback module in the circuit includes: Protocol chip U3, resistor R29, light-emitting diode U4A, capacitor C18A, resistor R30, resistor R14, resistor R15, capacitor C11, resistor R16, capacitor C12, resistor R18, resistor R19, resistor R28, thermistor NTC2, capacitor C14, and resistor R17; The third pin of the protocol chip U3 is electrically connected to the eighth end of the secondary side of the transformer T1 through the light-emitting source of the optocoupler U4A and the resistor R29 arranged in series. The input end of the light-emitting source of the optocoupler U4A is electrically connected to one end of the resistor R29, the other end of the resistor R29 is electrically connected to the eighth end of the secondary side of the transformer T1, the output end of the light-emitting source of the optocoupler U4A is electrically connected to the third pin of the protocol chip U3. A series of capacitor C18A and resistor R30 are connected in parallel with the light-emitting source of the optocoupler U4A and the resistor R29. One end of the capacitor C18A is electrically connected to one end of the resistor R30, and the connection between the capacitor C18A and the resistor R30 is electrically connected to the connection between the resistor R29 and the input end of the light-emitting source of the optocoupler U4A. The fourth pin of the protocol chip U3 is connected to the third pin of the protocol chip U3 through the serially arranged resistor R17 and capacitor C12. The fifth pin of the protocol chip U3 is connected to the third pin of the protocol chip U3 through the serially arranged resistor R16 and capacitor C11. The fifth pin of the protocol chip U3 is electrically connected to the eighth end of the secondary side of the transformer T1 through the serially arranged resistor R14. The fifth pin of the protocol chip U3 is grounded through the serially arranged resistor R15. The sixth pin of the protocol chip U3 is grounded through the serially arranged resistor R19. The seventh pin of the protocol chip U3 is grounded through the serially arranged resistor R28 and thermistor NTC2. The twenty-eighth pin of the protocol chip U3 is grounded through the serially arranged resistor R17 and capacitor C14.

[0013] Combined with the seventh embodiment of the first aspect, in the eighth embodiment of the first aspect, the electrostatic discharge protection module 600 in the circuit includes: The first resistor, the first capacitor, the first diode, the second resistor, the second capacitor, and the second diode; The twenty-third to twenty-seventh pins of the protocol chip U3, i.e., these VBUS1 pins, are electrically connected to the first charging interface 700. The first pin, the second pin, the thirtieth pin, the thirty-first pin, the thirty-second pin, and the ninth pin of the protocol chip U3, i.e., these VBUS2 pins, and the BUSA pin are electrically connected to the second charging interface 800. The protocol chip U3 is electrically connected to the first charging interface 700 through the first resistor. One end of the first resistor connected to the protocol chip U3 is grounded through the first capacitor, and one end of the first resistor connected to the first charging interface 700 is grounded through the first diode. The protocol chip U3 is electrically connected to the second charging interface 800 through the second resistor. One end of the second resistor connected to the protocol chip U3 is grounded through the second capacitor, and one end of the second resistor connected to the second charging interface 800 is grounded through the second diode.

[0014] According to a second aspect, an embodiment of the present invention further provides a switching power supply, and the switching power supply includes: a multi-port charging circuit for supporting a portable device according to any one of the above.

[0015] The multi-port charging circuit and the switching power supply for supporting a portable device of the present invention have the following beneficial effects compared with the prior art: Through an electromagnetic compatibility module, a chip power supply module, a synchronous rectification module, a sampling feedback module, a protocol chip feedback module, an electrostatic discharge protection module, a first charging interface, a second charging interface, a transformer, and a main control chip, a flyback switching power supply is provided, and the switching power supply supports powering a portable electronic device. The main control chip controls the input voltage to store energy at the edge of the transformer. Through the control of the main control chip, the previously stored back electromotive force is released to the load by the primary side of the transformer to provide energy for the load, that is, to charge the load. Moreover, this flyback switching power supply can achieve multiple outputs and charge multiple electronic devices in the load at the same time. And the protocol chip feedback module controls the first charging port and the second charging port to charge various electronic devices in the load through a preset charging protocol. The voltage conversion process only needs to use one transformer to charge electronic devices of different charging port types, and the overall circuit occupies less space. At the same time, the electromagnetic compatibility module effectively suppresses the electromagnetic interference of the circuit, and at the same time improves the anti-interference ability of the circuit itself to electromagnetic interference, optimizes the generated electromagnetic interference, so that the circuit meets the corresponding electromagnetic compatibility standard. The synchronous rectification module performs synchronous rectification on the input voltage. The protocol chip feedback module can provide a feedback signal for the sampling feedback module, and then the sampling feedback module outputs a feedback signal to the main control chip, and this process realizes isolated feedback. When it is detected that the output voltage exceeds the preset value, it is fed back to the main control chip through an isolation device, and the main control chip will generate a corresponding signal for protection. Therefore, the present invention can not only charge multiple electronic devices of different charging port types at the same time by only setting one transformer, and the overall occupied space is smaller, but also provide a stable voltage for the electronic devices to achieve more stable and safe charging. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0017] Figure 1 It is a schematic structural diagram of a multi-port charging circuit for supporting portable devices according to the present invention; Figure 2 It is a schematic circuit diagram of the primary side of the transformer T1 and the synchronous rectification module in the circuit diagram of the multi-port charging circuit for supporting portable devices according to the present invention; Figure 3 It is a schematic circuit diagram of the secondary side of the transformer T1 except for the synchronous rectification module in the circuit diagram of the multi-port charging circuit for supporting portable devices according to the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] The following will describe the technical solutions in the embodiments of the present invention clearly and completely in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative work shall fall within the protection scope of the present invention.

[0019] It should be noted that similar reference numerals and letters denote similar items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. In addition, the terms "first", "second", "third", etc. are only used for descriptive distinction and cannot be understood as indicating or implying relative importance.

[0020] In the description of the present application, it should also be noted that, unless otherwise clearly specified and limited, the terms "arranged", "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0021] Currently, most electronic devices are powered by switched-mode power supplies to save energy and improve work efficiency. With the popularization and application of portable electronic devices, in order to meet the charging requirements of more and more portable electronic devices, the chargers of these electronic devices are usually provided with multiple charging ports to facilitate charging multiple electronic devices simultaneously.

[0022] In the prior art, with the introduction of various charging interfaces, such as Type-A, Type-C, and USB-A interfaces, chargers with multiple interfaces have emerged. However, the output voltages of various charging interfaces may be different. It is very difficult to complete such a circuit design with only one transformer, which poses a safety hazard. If designed separately and independently, multiple transformers will be used, resulting in a relatively large overall volume of the charger.

[0023] In summary, there is a need to provide a switched-mode power supply with stable charging process, convenient to carry, and capable of multi-port charging.

[0024] The multi-port charging circuit and switched-mode power supply for supporting portable devices provided in this specification aim to provide a switched-mode power supply that can achieve more stable charging voltage and charge electronic devices of multiple different charging port types simultaneously through only one transformer.

[0025] Please refer to Figures 1 to 3 ,Figure 1 The structural schematic diagram of the multi-port charging circuit for supporting portable devices according to an embodiment of the present invention is shown, Figure 2 One of the circuit schematic diagrams of the multi-port charging circuit for supporting portable devices according to an embodiment of the present invention is shown, Figure 3 One of the circuit schematic diagrams of the multi-port charging circuit for supporting portable devices according to an embodiment of the present invention is shown.

[0026] Specifically, the circuit includes: An Electro Magnetic Compatibility (EMC) module 100, a chip power supply module 200, a synchronous rectification module 300, a sampling feedback module 400, a protocol chip feedback module 500, an Electro Static Discharge (ESD) protection module 600, a first charging interface 700, a second charging interface 800, a transformer T1, and a main control chip U1. Among them, the EMC module 100, the chip power supply module 200, the sampling feedback module 400, and the main control chip U1 are arranged on the primary side of the transformer T1, and the synchronous rectification module 300, the protocol chip feedback module 500, the ESD protection module 600, the first charging interface 700, and the second charging interface 800 are arranged on the secondary side of the transformer T1. The input voltage is electrically connected to the EMC module 100, the EMC module 100 is electrically connected to the primary side of the transformer T1 through a primary side absorption module, the synchronous rectification module 300 is electrically connected to the secondary side of the transformer T1, the synchronous rectification module 300 is electrically connected to the first charging interface 700 and the second charging interface 800 through the protocol chip feedback module 500 and the ESD protection module 600 in sequence, the main control chip U1 is electrically connected to the electromagnetic compatibility module 100, the main control chip U1 samples and feeds back from the output voltage through the sampling feedback module 400 and the protocol chip feedback module 500, and the sampling feedback module 400 is electrically connected to the main control chip U1 and the protocol chip feedback module 500.

[0027] In this embodiment, the input voltage is the mains power, that is, the AC grid voltage. After the input voltage is connected to the circuit, it will first enter the EMC module, that is, the EMC circuit.

[0028] More specifically, the EMC module 100 in this circuit includes: Common mode inductor LF1, rectifier bridge BD1, differential mode inductors L1 and L2, polarized capacitors EC1 and EC2. These electronic components mentioned above constitute the EMC module 100, that is, the EMC circuit. Among them, the common mode inductor LF1 has four terminals. The second terminal and the third terminal of the common mode inductor LF1 are connected between the live wire (L wire) and the neutral wire (N wire). The second terminal of the common mode inductor LF1 is electrically connected to the live wire, and the third terminal of the common mode inductor LF1 is electrically connected to the neutral wire. The first terminal and the fourth terminal of the common mode inductor LF1 are connected to the rectifier bridge BD1. The rectifier bridge BD1 also has four terminals. The first terminal of the common mode inductor LF1 is electrically connected to the second terminal of the rectifier bridge BD1, and the fourth terminal of the common mode inductor LF1 is electrically connected to the third terminal of the rectifier bridge BD1. The first terminal of the rectifier bridge BD1 is electrically connected to the primary absorption circuit through the series-connected differential mode inductor L1. The fourth terminal of the rectifier bridge BD1 is electrically connected to the primary absorption circuit through the series-connected differential mode inductor L2. Between the first terminal and the fourth terminal of the rectifier bridge BD1, there are electrically connected polarized capacitors EC1 and EC2 arranged in parallel. The positive electrode of the polarized capacitor EC1 is electrically connected between the first terminal of the rectifier bridge BD1 and the differential mode inductor L1. The negative electrode of the polarized capacitor EC1 is electrically connected between the fourth terminal of the rectifier bridge BD1 and the differential mode inductor L2. The positive electrode of the polarized capacitor EC2 is electrically connected between the differential mode inductor L1 and the primary absorption circuit. The negative electrode of the polarized capacitor EC2 is electrically connected between the differential mode inductor L2 and the primary absorption circuit.

[0029] The common mode inductor LF1 can attenuate the common mode current;; The rectifier bridge BD1 can rectify the input voltage received by the EMC module 300 on the primary side; The differential mode inductors L1, L2, polarized capacitors EC1 and EC2 play a filtering role, making the current output backward through the MC module 100 smoother.

[0030] The setting of the EMC module 100 can effectively suppress the electromagnetic interference of the circuit, and at the same time improve the anti-interference ability of the circuit itself to electromagnetic interference, optimize the electromagnetic interference generated therein, so that the circuit meets the corresponding electromagnetic compatibility standards.

[0031] In this embodiment, before the front end of the EMC module 100, that is, before the EMC module 100 accesses the input voltage, there are a fuse F1 and a thermistor NTC1. Among them, the fuse F1 is arranged on the live wire. One end of the fuse F1 is electrically connected to the live wire, and the other end of the fuse F1 is electrically connected to the second terminal of the common mode inductor L1. The thermistor NTC1 is arranged on the neutral wire. One end of the thermistor NTC1 is electrically connected to the neutral wire, and the other end of the thermistor NTC1 is electrically connected to the third terminal of the common mode inductor L1.

[0032] When the current flowing through the switching power supply is too large, the fuse F1 will disconnect to protect the circuit; a thermistor NTC1 is connected in series at the input end of the input voltage to increase the impedance of the circuit, so that the inrush current formed by the inrush voltage generated at the beginning of the operation of the circuit can be effectively suppressed. When the circuit enters the steady-state operation, due to the heating of the thermistor NTC1 caused by the continuous working current in the circuit, the resistance value of the thermistor NTC1 becomes very small, and the influence on the circuit can be almost completely ignored.

[0033] More specifically, the sampling feedback module 400 in this circuit includes: Resistor R4, resistor R5, resistor R6, resistor R7, resistor R8, resistor R9, capacitor C3, capacitor C4, capacitor C5, capacitor C7, optocoupler U4B and zener diode ZD1. These above-mentioned electronic components constitute the sampling feedback module 400, that is, the chip feedback circuit. Among them, the first pin of the main control chip U1, that is, the CS pin, is electrically connected to one end of the differential-mode inductor L2 far from the fourth end of the rectifier bridge BD1 through the series resistor R6. The ninth pin of the main control chip U1, that is, the EPAD pin, is connected to the connection between the differential-mode inductor L2 and the resistor R6 through the mutually parallel-connected resistors R4 and R5. One end of the resistor R4 and the resistor R5 is electrically connected to the ninth pin of the main control chip U1, and the other end of the resistor R4 and the resistor R5 is connected to the connection between the differential-mode inductor L2 and the resistor R6. The second pin of the main control chip U1, that is, the FB pin, is electrically connected to the optocoupler U4B and the zener diode ZD1 through the resistor R7. One end of the resistor R7 is electrically connected to the second pin of the main control chip U1, and the other end of the resistor R7 is respectively electrically connected to the input end of the receiver of the optocoupler U4B and the negative electrode of the zener diode ZD1. The output end of the receiver of the optocoupler U4B and the positive electrode of the zener diode ZD1 are grounded. The second pin of the main control chip U1 is grounded through the series capacitor C4. One end of the capacitor C4 is electrically connected to the second pin of the main control chip U1, and the other end of the capacitor C4 is grounded. The third pin of the main control chip U1, that is, the DEM pin, is grounded through the mutually parallel-connected resistor R9 and capacitor C7. One end of the resistor R9 and the capacitor C7 is electrically connected to the third pin of the main control chip U1, and the other end of the resistor R9 and the capacitor C7 is grounded. The third pin of the main control chip U1 is electrically connected to one end where the differential-mode inductor T1B is connected to the diode D2 through the resistor R8. The fourth pin of the main control chip U1, that is, the VDD pin, is grounded through the capacitor C5. One end of the capacitor C5 is electrically connected to the fourth pin of the main control chip U1, and the other end of the capacitor C5 is grounded.

[0034] The main control chip U1 is the control part and also the core part of this circuit. After the input voltage is obtained by the EMC module 100, the input voltage, that is, the mains power, will be fed back to the main control chip U1 at the input end for pulse width modulation (PWM) control processing. The main control chip U1 is responsible for regulating the output power and finally achieving a dynamic balance.

[0035] The main control chip U1 is connected to the rectified high-voltage direct current for the startup of the chip and the internal high-voltage circuit. In this way, the conduction of the MOS transistor inside the main control chip U1 is controlled by detecting the voltage of the corresponding pin. When the MOS transistor inside the main control chip U1 conducts and forms a loop, the same-name terminal of the primary winding of the transformer T1 is negative, and the same-name terminal of the secondary winding is also negative. The protocol chip feedback module 500 and the electrostatic discharge protection module 600 connected to the secondary side of the transformer T1 do not work, and the transformer T1 is responsible for storing energy; when the MOS transistor inside the main control chip U1 is cut off, due to the need to release the back electromotive force of the primary winding of the transformer T1, at this time, the same-name terminal of the primary winding of the transformer T1 is positive, and the same-name terminal of the secondary winding is also positive. The protocol chip feedback module 500 and the electrostatic discharge protection module 600 connected to the secondary side of the transformer T1 perform corresponding processing on the input voltage.

[0036] It can be seen that this circuit is powered by a flyback power supply. Preferably, the main control chip U1 uses a KP22082AESGAESOP-7 type chip. Specifically, the main control chip U1 Figure 1 has 9 pins shown. The sixth and seventh pins of the main control chip U1, these two GND pins, are grounded. The sixth and seventh pins of the main control chip U1 are also electrically connected to the third terminal of the primary side of the transformer T1 through the capacitor C6. The eighth pin of the main control chip U1, that is, the DRAIN pin, is also electrically connected to the third terminal of the primary side of the transformer T1.

[0037] The receiver of the optocoupler U4B and the light-emitting source of the optocoupler U4A together form a complete optocoupler. This optocoupler can sample and feedback the rectified output voltage. When the light-emitting source of the optocoupler U4B is powered on and conducts, it can further conduct the receiver, and then output a feedback signal to the main control chip U1. And because this optocoupler is an isolation device, this process realizes isolation feedback. When it is detected that the output voltage exceeds the preset value, it is fed back to the main control chip U1 through this optocoupler, and the main control chip U1 will generate a corresponding signal for protection.

[0038] More specifically, the chip power supply module 200 in this circuit includes: Inductor L3, differential-mode inductor T1B, diode D2, resistor R11, capacitor C8, resistor R10, and polarized capacitor EC3. These electronic components mentioned above constitute the chip power supply module 200, that is, the product chip power supply circuit, which is responsible for providing the voltage for the main control chip U1 to maintain its operation. Among them, the fifth pin of the main control chip U1, namely the SW pin, is grounded through the serially arranged inductor L3, resistor R10, diode D2, and differential-mode inductor T1B. The fifth pin of the main control chip U1 is electrically connected to one end of the inductor L3. The other end of the inductor L3 is electrically connected to one end of the resistor R10. The other end of the resistor R10 is electrically connected to the negative electrode of the diode D2. The positive electrode of the diode D2 is electrically connected to one end of the differential-mode inductor T1B. The other end of the differential-mode inductor T1B is grounded. A serially arranged resistor R11 and capacitor C8 are connected in parallel between the positive and negative electrodes of the diode D2. One end of the resistor R11 is electrically connected to the positive electrode of the diode D2. The other end of the resistor R11 is electrically connected to one end of the capacitor C8. The other end of the capacitor C8 is electrically connected to the negative electrode of the diode D2. The inductor L3 and the resistor R10 are electrically connected to the grounded end of the differential-mode inductor T1B through the polarized capacitor EC3. The positive electrode of the polarized capacitor EC3 is electrically connected between the inductor L3 and the resistor R10. The negative electrode of the polarized capacitor EC3 is electrically connected to the grounded end of the differential-mode inductor T1B.

[0039] Through the coordinated cooperation of each electronic component in the chip power supply module 200, it can ensure the stable and reliable operation of the main control chip U1. Through mechanisms such as voltage conversion, filtering, and protection, it provides a pure, stable, and efficient working environment for the main control chip U1. Each capacitor, resistor, and polarized capacitor among them can filter out low-frequency ripples and high-frequency noises. The setting of the inductor can effectively suppress the conduction of electromagnetic interference (EMI). The setting of the diode D2 can provide reverse connection protection for the main control chip U1.

[0040] In this embodiment, the primary rectification module is composed of a rectifier bridge BD1, a diode D1, a diode D2, a polarized capacitor EC1, and a capacitor C3. The rectifier bridge BD1 has four terminals. The first terminal of the rectifier bridge BD1 is electrically connected to the third terminal of the common-mode inductor LF1. The first terminal of the rectifier bridge BD1 is electrically connected to a resistor R15 through a series-connected diode D1. The positive electrode of the diode D1 is electrically connected to the first terminal of the rectifier bridge BD1, and the negative electrode of the diode D1 is electrically connected to the resistor R15. The second terminal of the rectifier bridge BD1 is electrically connected to the fourth terminal of the common-mode inductor LF1. The fourth terminal of the common-mode inductor LF1 is electrically connected to the resistor R15 through a series-connected diode C2. The positive electrode of the diode C2 is electrically connected to the fourth terminal of the common-mode inductor LF1, and the negative electrode of the diode C2 is electrically connected to the resistor R15. The third terminal of the rectifier bridge BD1 is electrically connected to the absorption circuit 300. The fourth terminal of the rectifier bridge BD1 is grounded, and a parallel-connected polarized capacitor EC1 and capacitor C3 are connected between the third terminal and the fourth terminal of the rectifier bridge BD1. One end of the capacitor C3 is connected between the third terminal and the fourth terminal of the rectifier bridge BD1, and the other end of the capacitor C3 is connected to the power ground. The positive electrode of the polarized capacitor EC1 is connected between the third terminal and the fourth terminal of the rectifier bridge BD1, and the negative electrode of the polarized capacitor EC1 is connected to the power ground.

[0041] It can be understood that the primary rectification module is the rectification circuit on the primary side of the transformer T1. The rectifier bridge BD1 in the primary rectification module rectifies the input voltage received by the EMC module 300 on the primary side, and corrects the voltage waveform through the charging and discharging of the polarized capacitor EC1 and the capacitor C3.

[0042] More specifically, the primary absorption module in this circuit includes: A capacitor C2, a resistor R2, a resistor R3, and a diode D1. These electronic components constitute the primary absorption module, that is, the primary absorption circuit. The third terminal of the primary side of the transformer T1 is connected to the positive electrode of the diode D1. The negative electrode of the diode D1 is electrically connected to one end of a resistor R3. The other end of the resistor R3 is electrically connected between the differential-mode inductor L1 and the fourth terminal of the primary side of the transformer T1 through a mutually parallel-connected resistor R2 and capacitor C2.

[0043] Since the transformer T1 is also composed of winding coils and the generated magnetism, when the primary winding circuit of the transformer T1 is disconnected, there is a back electromotive force in the primary winding that needs to be released. Therefore, at this time, the same-name terminal of the primary winding is the positive electrode. At this time, the current flows through the diode D1 to charge the capacitor C2, and the capacitor C2 then discharges through other resistors in the primary absorption module. In this way, the primary absorption module can control the discharge voltage within a preset range.

[0044] More specifically, the synchronous rectification module 300 in this circuit includes: The rectifier chip U2, capacitor C9, capacitor C10, and resistor R12. These above-mentioned electronic components constitute the synchronous rectification module 300, that is, the synchronous rectification circuit. Among them, the rectifier chip U2 has 8 pins. The first pin, the fifth pin, the fifth pin, the seventh pin, and the eighth pin of the rectifier chip U2, namely the above-mentioned pins corresponding to the HV pin, DRAIN pin, DRAIN pin, DRAIN pin, and DRAIN pin respectively, are all electrically connected to the seventh end of the secondary side of the transformer T1. The third pin and the fourth pin of the rectifier chip U2, namely the two GND pins, are both electrically connected to the seventh end of the secondary side of the transformer T1 through the serially arranged capacitor C10 and resistor R12. One end of the resistor R12 is electrically connected to the seventh end of the secondary side of the transformer T1, the other end of the resistor R12 is electrically connected to one end of the capacitor C10, and the other end of the capacitor C10 is electrically connected to the third pin and the fourth pin of the rectifier chip U2. The second pin of the rectifier chip U2, namely the GND pin, is electrically connected to the end of the capacitor C10 far from the resistor R12 through the capacitor C9. In this way, the second pin of the rectifier chip U2, namely the GND pin, is electrically connected to the seventh end of the secondary side of the transformer T1 through the serially arranged capacitor C9, capacitor C10, and resistor R12.

[0045] It can be understood that the synchronous rectification module 300 is the rectification circuit on the secondary side of the transformer T1, responsible for performing synchronous rectification processing on the input voltage, so as to provide energy for the subsequent circuit and the load side. The rectifier chip U2 is responsible for performing the above-mentioned synchronous rectification processing on the input voltage. The resistor R12, capacitor C9, and capacitor C10 outside the rectifier chip U2 work together in a collaborative manner to ensure the stable and efficient operation of the rectifier chip U2, and at the same time protect the rectifier chip U2 from voltage fluctuations, noise, transient interference, etc.

[0046] Preferably, the rectifier chip U2 in the synchronous rectification module 300 uses a KP41662SGA model chip.

[0047] More specifically, the protocol chip feedback module 500 in this circuit includes: Protocol chip U3, resistor R29, light-emitting diode U4A, capacitor C18A, resistor R30, resistor R14, resistor R15, capacitor C11, resistor R16, capacitor C12, resistor R18, resistor R19, resistor R28, thermistor NTC2, capacitor C14, and resistor R17. These above-mentioned electronic components constitute the protocol chip feedback module 500, that is, the protocol chip feedback circuit. Among them, the third pin of the protocol chip U3, namely the OPTO pin, is electrically connected to the eighth end of the secondary side of the transformer T1 through the light-emitting source of the optocoupler U4A and the resistor R29 arranged in series. The input end of the light-emitting source of the optocoupler U4A is electrically connected to one end of the resistor R29, and the other end 9 of the resistor R29 is electrically connected to the eighth end of the secondary side of the transformer T1. The output end of the light-emitting source of the optocoupler U4A is electrically connected to the third pin of the protocol chip U3. A series of capacitor C18A and resistor R30 are connected in parallel with the light-emitting source of the optocoupler U4A and the resistor R29. One end of the capacitor C18A is electrically connected to one end of the resistor R30. The connection between the capacitor C18A and the resistor R30 is electrically connected to the connection between the resistor R29 and the input end of the light-emitting source of the optocoupler U4A. The fourth pin of the protocol chip U3, namely the IFB pin, is connected to the third pin of the protocol chip U3 through the resistor R17 and the capacitor C12 arranged in series. The fifth pin of the protocol chip U3, namely the VFB pin, is connected to the third pin of the protocol chip U3 through the resistor R16 and the capacitor C11 arranged in series. The fifth pin of the protocol chip U3 is electrically connected to the eighth end of the secondary side of the transformer T1 through the series resistor R14. The fifth pin of the protocol chip U3 is grounded through the series resistor R15. The sixth pin of the protocol chip U3, namely the DCV pin, is grounded through the series resistor R19. The seventh pin of the protocol chip U3, namely the NTC pin, is grounded through the series resistor R28 and the thermistor NTC2. The twenty-eighth pin of the protocol chip U3, namely the VDD pin, is grounded through the series resistor R17 and the capacitor C14.

[0048] In the protocol chip feedback module 500, the protocol chip U3 controls the first charging port 700 and the second charging port 800 to charge various devices in the load through a preset charging protocol. The preset charging protocol can be a power delivery protocol (USB Power Delivery, PD) protocol, a quick charge (QC) protocol, etc. The PD protocol is a power transmission protocol based on the USB Type-C interface. It adopts a two-way communication mechanism, allowing devices to negotiate voltage and current to achieve a more flexible charging solution. By using the Type-C interface, the PD protocol can achieve higher charging speed and higher energy transmission efficiency. The QC protocol is a high-voltage fast charging technology based on the USB Type-A interface, which adds a special chip to the USB cable. The QC protocol allows communication between the charger and the device to determine the optimal charging rate, and the QC protocol supports multiple different fast charging levels.

[0049] In this embodiment, the capacitor C14 that plays a decoupling role will be arranged as close as possible to the protocol chip U3.

[0050] Preferably, the protocol chip U3 uses a chip of model HUSB382. Specifically, the protocol chip U3 Figure 2 shows 33 pins. The three VIN pins, namely the twentieth pin, the twenty-first pin, and the thirty-third pin of the protocol chip U3, are grounded through the capacitors C20 and C20A connected in parallel with each other. The twenty-ninth pin of the protocol chip U3, i.e., the GND pin, is grounded.

[0051] More specifically, the ESD protection module 500 in this circuit includes: a first resistor, a first capacitor, a first diode, a second resistor, a second capacitor, and a second diode. Among them, the twenty-third pin to the twenty-seventh pin of the protocol chip U3, i.e., these VBUS1 pins, are electrically connected to the first charging interface 700. The first pin, the second pin, the thirtieth pin, the thirty-first pin, the thirty-second pin, and the ninth pin of the protocol chip U3, i.e., these VBUS2 pins, as well as the BUSA pin, are electrically connected to the second charging interface 800. The protocol chip U3 is electrically connected to the first charging interface 700 through the first resistor. One end of the first resistor connected to the protocol chip U3 is grounded through the first capacitor, and one end of the first resistor connected to the first charging interface 700 is grounded through the first diode. The protocol chip U3 is electrically connected to the second charging interface 800 through the second resistor. One end of the second resistor connected to the protocol chip U3 is grounded through the second capacitor, and one end of the second resistor connected to the second charging interface 800 is grounded through the second diode.

[0052] Please refer to Figure 2, the first resistor includes resistors R22, R23, R24, and R25 respectively disposed on the nineteenth to sixteenth pins. The first capacitor includes capacitors C18, C17, C16, and C15 that are grounded at one end where resistors R22, R23, R24, and R25 are connected to the pins of protocol chip U3. The first diode includes diodes TVS1, TVS2, TVS3, and TVS4 that are grounded at one end where resistors R22, R23, R24, and R25 are connected to the first charging interface 700. The positive electrode of the first diode is grounded, and the negative electrode of the first diode is connected to the first resistor.

[0053] The second resistor includes resistors R27 and R26 respectively disposed on the tenth and eleventh pins. The second capacitor includes capacitors C21 and C19 that are grounded at one end where resistors R27 and R26 are connected to the pins of protocol chip U3. The second diode includes diodes TVS5 and TVS6 that are grounded at one end where resistors R27 and R26 are connected to the second charging interface 800. The positive electrode of the second diode is grounded, and the negative electrode of the second diode is connected to the first resistor Both the first and second diodes can be transient voltage suppression diodes.

[0054] Preferably, the first charging interface 700 is a Type-C port, and the second charging interface 800 is a USB-A port. These two charging interfaces can also be grounded using transient voltage suppression diodes to protect the interfaces. At the same time, the current sampling is carried out through standard differential traces.

[0055] In an embodiment of the present invention, a switching power supply implemented based on the above multi-port charging circuit for supporting portable devices is further provided. The working mode of the switching power supply is as described in the above multi-port charging circuit for supporting portable devices, and will not be elaborated here.

[0056] The multi-port charging circuit and switching power supply for supporting portable devices provided by the present invention, through the electromagnetic compatibility module 100, chip power supply module 200, synchronous rectification module 300, sampling feedback module 400, protocol chip feedback module 500, electrostatic discharge protection module 600, first charging interface 700, second charging interface 800, transformer T1 and main control chip U1, provide a flyback switching power supply and the switching power supply supports powering portable electronic devices. The main control chip U1 controls the input voltage to store energy at the edge of the transformer T1. Through the control of the main control chip U1, the previously stored back electromotive force is released to the load by the primary side of the transformer T1 to provide energy for the load, that is, to charge the load. Moreover, this flyback switching power supply can achieve multiple outputs and charge multiple electronic devices in the load at the same time. And the protocol chip feedback module 500 controls the first charging port 700 and the second charging port 800 to charge various electronic devices in the load through a preset charging protocol. The voltage conversion process only needs to use one transformer T1 to charge electronic devices of different charging port types, and the overall circuit occupies less space. At the same time, the electromagnetic compatibility module 100 effectively suppresses the electromagnetic interference of the circuit, and at the same time improves the anti-interference ability of the circuit itself to electromagnetic interference, optimizes the electromagnetic interference generated therein, so that the circuit meets the corresponding electromagnetic compatibility standards. The synchronous rectification module 300 performs synchronous rectification on the input voltage, and the protocol chip feedback module 500 can provide a feedback signal for the sampling feedback module 400, and then output a feedback signal to the main control chip U1 through the sampling feedback module 400, and this process realizes isolated feedback. When it is detected that the output voltage exceeds the preset value, it is fed back to the main control chip U1 through an isolation device, and the main control chip U1 will generate a corresponding signal for protection. Therefore, the present invention can not only charge multiple electronic devices of different charging port types at the same time by only setting one transformer T1, and the overall occupies less space, but also provide a stable voltage for the electronic devices to achieve more stable and safe charging.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. And these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-port charging circuit for supporting portable devices, characterized in that: The circuit includes: an electromagnetic compatibility module 100, a chip power supply module 200, a synchronous rectification module 300, a sampling feedback module 400, a protocol chip feedback module 500, an electrostatic discharge protection module 600, a first charging interface 700, a second charging interface 800, a transformer T1, and a main control chip U1; The electromagnetic compatibility module 100, the chip power supply module 200, the sampling feedback module 400, and the main control chip U1 are arranged on the primary side of the transformer T1. The synchronous rectification module 300, the protocol chip feedback module 500, the electrostatic discharge protection module 600, the first charging interface 700, and the second charging interface 800 are arranged on the secondary side of the transformer T1. The input voltage is electrically connected to the electromagnetic compatibility module 100. The electromagnetic compatibility module 100 is electrically connected to the primary side of the transformer T1 through a primary absorption module. The synchronous rectification module 300 is electrically connected to the secondary side of the transformer T1. The synchronous rectification module 300 is electrically connected to the first charging interface 700 and the second charging interface 800 through the protocol chip feedback module 500 and the electrostatic discharge protection module 600 in sequence. The main control chip U1 is electrically connected to the electromagnetic compatibility module 100. The main control chip U1 samples and feeds back from the output voltage through the sampling feedback module 400 and the protocol chip feedback module 500. The sampling feedback module 400 is electrically connected to the main control chip U1 and the protocol chip feedback module 500.

2. The multi-port charging circuit for supporting a portable device according to claim 1, wherein: The electromagnetic compatibility module 100 in the circuit includes: a common mode inductor LF1, a rectifier bridge BD1, a differential mode inductor L1, a differential mode inductor L2, a polarized capacitor EC1, and a polarized capacitor EC2; The second end and the third end of the common mode inductor LF1 are connected between the live wire and the neutral wire. The second end of the common mode inductor LF1 is electrically connected to the live wire, and the third end of the common mode inductor LF1 is electrically connected to the neutral wire. The first end and the fourth end of the common mode inductor LF1 are connected to the rectifier bridge BD1. The first end of the common mode inductor LF1 is electrically connected to the second end of the rectifier bridge BD1, and the fourth end of the common mode inductor LF1 is electrically connected to the third end of the rectifier bridge BD1. The first end of the rectifier bridge BD1 is electrically connected to the primary absorption circuit through the series-connected differential mode inductor L1. The fourth end of the rectifier bridge BD1 is electrically connected to the primary absorption circuit through the series-connected differential mode inductor L2. A parallel-connected polarized capacitor EC1 and polarized capacitor EC2 are electrically connected between the first end and the fourth end of the rectifier bridge BD1. The positive electrode of the polarized capacitor EC1 is electrically connected between the first end of the rectifier bridge BD1 and the differential mode inductor L1, and the negative electrode of the polarized capacitor EC1 is electrically connected between the fourth end of the rectifier bridge BD1 and the differential mode inductor L2. The positive electrode of the polarized capacitor EC2 is electrically connected between the differential mode inductor L1 and the primary absorption circuit, and the negative electrode of the polarized capacitor EC2 is electrically connected between the differential mode inductor L2 and the primary absorption circuit.

3. The multi-port charging circuit for supporting a portable device according to claim 2, characterized in that: A fuse F1 and a thermistor NTC1 are provided before the front end of the electromagnetic compatibility module 100; The fuse F1 is arranged on the live wire. One end of the fuse F1 is electrically connected to the live wire, and the other end of the fuse F1 is electrically connected to the second end of the common mode inductor L1. The thermistor NTC1 is arranged on the neutral wire. One end of the thermistor NTC1 is electrically connected to the neutral wire, and the other end of the thermistor NTC1 is electrically connected to the third end of the common mode inductor L1.

4. The multi-port charging circuit for supporting a portable device according to claim 2, wherein: The chip power supply module 200 in the circuit includes: Inductor L3, differential mode inductor T1B, diode D2, resistor R11, capacitor C8, resistor R10, and polarized capacitor EC3; The fifth pin of the main control chip U1 is grounded through the series-connected inductor L3, resistor R10, diode D2, and differential mode inductor T1B. The fifth pin of the main control chip U1 is electrically connected to one end of the inductor L3. The other end of the inductor L3 is electrically connected to one end of the resistor R10. The other end of the resistor R10 is electrically connected to the negative electrode of the diode D2. The positive electrode of the diode D2 is electrically connected to one end of the differential mode inductor T1B. The other end of the differential mode inductor T1B is grounded. A series-connected resistor R11 and capacitor C8 are connected in parallel between the positive and negative electrodes of the diode D2. One end of the resistor R11 is electrically connected to the positive electrode of the diode D2. The other end of the resistor R11 is electrically connected to one end of the capacitor C8. The other end of the capacitor C8 is electrically connected to the negative electrode of the diode D2. Between the inductor L3 and the resistor R10, it is electrically connected to the grounded end of the differential mode inductor T1B through the polarized capacitor EC3. The positive electrode of the polarized capacitor EC3 is electrically connected between the inductor L3 and the resistor R10, and the negative electrode of the polarized capacitor EC3 is electrically connected to the grounded end of the differential mode inductor T1B.

5. The multi-port charging circuit for supporting a portable device according to claim 4, wherein: The sampling feedback module 400 in the circuit includes: Resistor R4, resistor R5, resistor R6, resistor R7, resistor R8, resistor R9, capacitor C3, capacitor C4, capacitor C5, capacitor C7, optocoupler U4B, and zener diode ZD1; The first pin of the main control chip U1 is electrically connected to one end of the differential mode inductor L2 away from the fourth end of the rectifier bridge BD1 through a series resistor R6. The ninth pin of the main control chip U1, i.e., the EPAD pin, is connected to the connection between the differential mode inductor L2 and the resistor R6 through the mutually parallel resistors R4 and R5. One end of the resistor R4 and the resistor R5 is electrically connected to the ninth pin of the main control chip U1, and the other end of the resistor R4 and the resistor R5 is connected to the connection between the differential mode inductor L2 and the resistor R6. The second pin of the main control chip U1 is electrically connected to the optocoupler U4B and the zener diode ZD1 through a resistor R7. One end of the resistor R7 is electrically connected to the second pin of the main control chip U1, and the other end of the resistor R7 is respectively electrically connected to the input end of the receiver of the optocoupler U4B and the negative electrode of the zener diode ZD1. The output end of the receiver of the optocoupler U4B and the positive electrode of the zener diode ZD1 are grounded. The second pin of the main control chip U1 is grounded through a series capacitor C4. One end of the capacitor C4 is electrically connected to the second pin of the main control chip U1, and the other end of the capacitor C4 is grounded. The third pin of the main control chip U1 is grounded through the mutually parallel resistor R9 and capacitor C7. One end of the resistor R9 and the capacitor C7 is electrically connected to the third pin of the main control chip U1, and the other end of the resistor R9 and the capacitor C7 is grounded. The third pin of the main control chip U1 is electrically connected to one end where the differential mode inductor T1B is connected to the diode D2 through a resistor R8. The fourth pin of the main control chip U1 is grounded through a capacitor C5. One end of the capacitor C5 is electrically connected to the fourth pin of the main control chip U1, and the other end of the capacitor C5 is grounded.

6. The multi-port charging circuit for supporting a portable device according to claim 5, wherein: The primary side absorption module in the circuit includes: Capacitor C2, resistor R2, resistor R3, and diode D1; The third end of the primary side of the transformer T1 is connected to the positive electrode of the diode D1. The negative electrode of the diode D1 is electrically connected to one end of the resistor R3. The other end of the resistor R3 is connected to the connection between the differential mode inductor L1 and the fourth end of the primary side of the transformer T1 through the mutually parallel resistor R2 and capacitor C2.

7. The multi-port charging circuit for supporting a portable device according to claim 6, wherein: The synchronous rectification module 300 in the circuit includes: Rectification chip U2, capacitor C9, capacitor C10, and resistor R12; The first pin, fifth pin, fifth pin, seventh pin, and eighth pin of the rectification chip U2 are all electrically connected to the seventh end of the secondary side of the transformer T1. The third pin and the fourth pin of the rectification chip U2 are both electrically connected to the seventh end of the secondary side of the transformer T1 through the series capacitor C10 and resistor R12. One end of the resistor R12 is electrically connected to the seventh end of the secondary side of the transformer T1, and the other end of the resistor R12 is electrically connected to one end of the capacitor C10. The other end of the capacitor C10 is electrically connected to the third pin and the fourth pin of the rectification chip U2. The second pin of the rectification chip U2, i.e., the GND pin, is electrically connected to the end of the capacitor C10 away from the resistor R12 through the capacitor C9.

8. The multi-port charging circuit for supporting a portable device according to claim 7, characterized in that: The protocol chip feedback module 500 in the circuit includes: Protocol chip U3, resistor R29, light-emitting diode U4A, capacitor C18A, resistor R30, resistor R14, resistor R15, capacitor C11, resistor R16, capacitor C12, resistor R18, resistor R19, resistor R28, thermistor NTC2, capacitor C14, and resistor R17; The third pin of the protocol chip U3 is electrically connected to the eighth end of the secondary side of the transformer T1 through the light-emitting source of the optocoupler U4A and the resistor R29 connected in series. The input end of the light-emitting source of the optocoupler U4A is electrically connected to one end of the resistor R29, and the other end 9 of the resistor R29 is electrically connected to the eighth end of the secondary side of the transformer T1. The output end of the light-emitting source of the optocoupler U4A is electrically connected to the third pin of the protocol chip U3. A capacitor C18A and a resistor R30 connected in series are connected in parallel with the light-emitting source of the optocoupler U4A and the resistor R29. One end of the capacitor C18A is electrically connected to one end of the resistor R30. The connection between the capacitor C18A and the resistor R30 is electrically connected to the connection between the resistor R29 and the input end of the light-emitting source of the optocoupler U4A. The fourth pin of the protocol chip U3 is connected to the third pin of the protocol chip U3 through the resistor R17 and the capacitor C12 connected in series. The fifth pin of the protocol chip U3 is connected to the third pin of the protocol chip U3 through the resistor R16 and the capacitor C11 connected in series. The fifth pin of the protocol chip U3 is electrically connected to the eighth end of the secondary side of the transformer T1 through the resistor R14 connected in series. The fifth pin of the protocol chip U3 is grounded through the resistor R15 connected in series. The sixth pin of the protocol chip U3 is grounded through the resistor R19 connected in series. The seventh pin of the protocol chip U3 is grounded through the resistor R28 and the thermistor NTC2 connected in series. The twenty-eighth pin of the protocol chip U3 is grounded through the resistor R17 and the capacitor C14 connected in series.

9. The multi-port charging circuit for supporting portable devices according to claim 8, wherein: The electrostatic discharge protection module 600 in the circuit includes: A first resistor, a first capacitor, a first diode, a second resistor, a second capacitor, and a second diode; The twenty-third to twenty-seventh pins of the protocol chip U3, that is, these VBUS1 pins, are electrically connected to the first charging interface 700. The first, second, thirtieth, thirty-first, thirty-second, and ninth pins of the protocol chip U3, that is, these VBUS2 pins, and the BUSA pin are electrically connected to the second charging interface 800. The protocol chip U3 is electrically connected to the first charging interface 700 through the first resistor. The end of the first resistor connected to the protocol chip U3 is grounded through the first capacitor. The end of the first resistor connected to the first charging interface 700 is grounded through the first diode. The protocol chip U3 is electrically connected to the second charging interface 800 through the second resistor. The end of the second resistor connected to the protocol chip U3 is grounded through the second capacitor. The end of the second resistor connected to the second charging interface 800 is grounded through the second diode.

10. A switching power supply, characterized in that: The switching power supply includes: The multi-port charging circuit for supporting portable devices according to any one of claims 1-9.

Images