Multi-port fast charging control circuit and method thereof, and charger

Abstract

This invention relates to a multi-port fast charging control circuit and method, and a charger. The circuit includes an AC / DC conversion unit, a main control unit, a step-down circuit unit, a first charging interface, a second charging interface, a first switching unit, a second switching unit, a third switching unit, and a fourth switching unit. The voltage input terminal of the step-down circuit unit is connected to the voltage output terminal of the AC / DC conversion unit. The main control unit controls the on / off states of the first, second, third, and fourth switching units based on the device connection status and power demand of the first and second charging interfaces, thereby controlling the AC / DC conversion unit to directly supply power to the charging interface with the highest power demand. Furthermore, when the power demands of the first and second charging interfaces are the same, the main control unit controls the AC / DC conversion unit to directly supply power to the previously connected charging interface, and controls the step-down circuit unit to supply power to the other charging interface. This application simplifies the circuit and reduces wiring difficulty and cost.

Description

Technical Field

[0001] This invention relates to the field of charging technology, and in particular to a multi-port fast charging control circuit and method, and a charger. Background Technology

[0002] With the widespread adoption of fast charging technology and the increasing number of smart devices owned by users, multi-port fast chargers have become a popular charging accessory. Users only need one charger to charge multiple smart devices simultaneously, bringing great convenience to consumers.

[0003] In implementing multi-port fast charging control circuits, two-way BUCK circuits or two-way BUCK-TOOST circuits are typically used to achieve blind-plug fast charging for multiple ports. However, two-way BUCK circuits or two-way BUCK-TOOST circuits contain large components such as control chips, inductors, and MOSFETs, occupying a large space overall. They are also complex, difficult to lay out and route, and have high costs, especially the two-way BUCK-TOOST circuits. Summary of the Invention

[0004] This invention provides a multi-port fast charging control circuit and method, as well as a charger, to solve the problems of complex circuits, difficult layout and wiring, and high cost of existing multi-port fast charging control circuits.

[0005] This invention discloses a multi-port fast charging control circuit, including an AC / DC conversion unit, a main control unit, a step-down circuit unit, a first charging interface, a second charging interface, a first switching unit, a second switching unit, a third switching unit, and a fourth switching unit;

[0006] The first switching unit is located between the voltage output terminal of the AC / DC conversion unit and the first charging interface; the second switching unit is located between the voltage output terminal of the AC / DC conversion unit and the second charging interface. The third switch unit is located between the voltage output terminal of the step-down circuit unit and the first charging interface; the fourth switch unit is located between the voltage output terminal of the step-down circuit unit and the second charging interface. The voltage input terminal of the step-down circuit unit is connected to the voltage output terminal of the AC-DC conversion unit; The main control unit is used to control the on / off state of the first charging interface, the second charging interface, the third switching unit, and the fourth switching unit according to the device access status and power demand of the first charging interface and the second charging interface, thereby controlling the AC / DC conversion unit to directly supply power to the charging interface with the highest power demand; and when the power demand of the first charging interface and the second charging interface are the same, controlling the AC / DC conversion unit to directly supply power to the charging interface that is connected first, and controlling the step-down circuit unit to supply power to the other charging interface.

[0007] Optionally, the multi-port fast charging control circuit further includes a third charging interface. A fifth switching unit is provided between the third charging interface and the voltage output terminal of the step-down circuit unit. The main control unit is also used to control the on / off state of the fifth switching unit according to the device access status and power demand of the third charging interface, thereby controlling the step-down circuit unit to supply power to the third charging interface.

[0008] Optionally, the main control unit includes a protocol chip, and the step-down circuit unit includes a step-down chip, an inductor, and an energy storage capacitor; the first voltage adjustment terminal of the protocol chip is connected to the AC / DC conversion unit, and its second voltage adjustment terminal is connected to the step-down chip; the step-down chip is connected to the first terminal of the inductor; the second terminal of the inductor is connected to the first terminal of the energy storage capacitor, the third switching unit, and the fourth switching unit; the second terminal of the energy storage capacitor is grounded.

[0009] Optionally, the first switching unit includes a first NMOS transistor and a first resistor. The first resistor is connected in series between the first NMOS transistor and the first control terminal of the main control unit. The drain of the first NMOS transistor is connected to the voltage output terminal of the AC-DC conversion unit, and its source is connected to the first charging interface. And / or, the second switching unit includes a second NMOS transistor and a second resistor, the second resistor being connected in series between the second NMOS transistor and the second control terminal of the main control unit, the drain of the second NMOS transistor being connected to the voltage output terminal of the AC / DC conversion unit, and its source being connected to the second charging interface.

[0010] Optionally, the third switching unit includes a third NMOS transistor, a fourth NMOS transistor, and a third resistor; the source of the third NMOS transistor is connected to the source of the fourth NMOS transistor; the drain of the third NMOS transistor is connected to the voltage output terminal of the buck circuit unit; the drain of the fourth NMOS transistor is connected to the second charging interface; the gate of the third NMOS transistor is connected to the gate of the fourth NMOS transistor and connected to the third control terminal of the main control unit through the third resistor. And / or, the fourth switching unit includes a fifth NMOS transistor, a sixth NMOS transistor, and a fourth resistor; the source of the fifth NMOS transistor is connected to the source of the sixth NMOS transistor; the drain of the fifth NMOS transistor is connected to the voltage output terminal of the buck circuit unit; the drain of the sixth NMOS transistor is connected to the second charging interface; the gate of the fifth NMOS transistor is connected to the gate of the sixth NMOS transistor and connected to the fourth control terminal of the main control unit through the fourth resistor.

[0011] Optionally, the fifth switching unit includes a seventh NMOS transistor, an eighth NMOS transistor, and a fifth resistor; the source of the seventh NMOS transistor is connected to the source of the eighth NMOS transistor; the drain of the seventh NMOS transistor is connected to the voltage output terminal of the buck circuit unit; the drain of the eighth NMOS transistor is connected to the third charging interface; and the gate of the seventh NMOS transistor is connected to the gate of the eighth NMOS transistor and connected to the fifth control terminal of the main control unit through the fifth resistor.

[0012] The present invention also discloses a charger, including a circuit board and a multi-port fast charging control circuit as described in any of the preceding claims, wherein the multi-port fast charging control circuit is disposed on the circuit board.

[0013] This invention also discloses a multi-port fast charging control method, implemented using the multi-port fast charging control circuit described in any of the above claims, the multi-port fast charging control method comprising the following steps: Identify the device connection status and power demand of the first charging interface and the second charging interface; Based on the identification result, the first switch unit, the second switch unit, the third switch unit, and the fourth switch unit are controlled to switch on and off, thereby controlling the AC / DC conversion unit to directly supply power to the charging interface with the highest power demand; and when the power demand of the first charging interface and the second charging interface is the same, the AC / DC conversion unit is controlled to directly supply power to the charging interface that is connected first, and the step-down circuit unit is controlled to supply power to the other charging interface.

[0014] Optionally, the specific steps of controlling the on / off states of the first, second, third, fourth, and fifth switching units based on the identification result include: When only the first charging interface or the second charging interface is connected to the device, the corresponding first switching unit or the second switching unit is turned on, the other switching units are turned off, and the AC / DC conversion unit is controlled to directly supply power to the first charging interface or the second charging interface connected to the device. When both the first charging interface and the second charging interface are connected to the device, the switching unit between the charging interface with the highest required power and the AC / DC conversion unit is controlled to be turned on according to the power demand of the connected device, and the switching unit between the other charging interface and the step-down circuit unit is controlled to be turned on; if the required power of the first charging interface and the second charging interface is the same, the switching unit between the charging interface connected to the device first and the AC / DC conversion unit is turned on, and the switching unit between the other charging interface and the step-down circuit unit is controlled to be turned on.

[0015] Optionally, the multi-port fast charging control circuit further includes a third charging interface, and a fifth switching unit is provided between the third charging interface and the voltage output terminal of the step-down circuit unit. The multi-port fast charging control method further includes the following steps: Identify the device connection status and power requirement of the third charging interface; Based on the identification results, the first switch unit, the second switch unit, the third switch unit, the fourth switch unit, and the fifth switch unit are controlled to turn on and off, thereby controlling the AC / DC conversion unit to directly supply power to the first or second charging interface with the highest power demand, while the other charging interfaces share the power supply of the step-down circuit unit. If the first charging interface and the second charging interface have the same power requirements, the AC / DC conversion unit is controlled to directly supply power to the charging interface that is connected first, and the remaining charging interfaces share the power supply of the step-down circuit unit.

[0016] The beneficial effects of the multi-port fast charging control method provided in this invention are as follows: By setting up a first switch unit, a second switch unit, a third switch unit, and a fourth switch unit, and cooperating with the main control unit, the switching units are flexibly controlled according to the device access status and power demand of the first and second charging interfaces, and according to the access order of the two interfaces when their power demands are the same. This allows the charging interface with high power demand to be directly powered by the AC-DC conversion unit, while the other charging interface is powered by the step-down circuit unit. This invention only requires setting up one step-down circuit unit to realize blind-plug fast charging of the first and second charging interfaces, which greatly reduces the use of large components such as control chips and inductors, simplifies the circuit structure, reduces the difficulty of layout and wiring, effectively reduces hardware costs, and prioritizes the use of the AC-DC conversion unit for power supply under any load conditions, resulting in lower losses and improved conversion efficiency. Attached Figure Description

[0017] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. In the accompanying drawings: Figure 1 This is a structural block diagram of the multi-port fast charging control circuit according to an embodiment of the present invention; Figure 2This is a circuit diagram of the main control unit connecting the AC / DC conversion unit, the first charging interface, and the second charging interface according to an embodiment of the present invention; Figure 3 This is a circuit diagram of the step-down circuit unit of this invention connected to the first charging interface, the second charging interface and the third charging interface; Figure 4 This is a simplified schematic diagram of a charger according to an embodiment of the present invention; Figure 5 This is a flowchart illustrating the multi-port fast charging control method according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the process of controlling the on / off state of the first switch unit, the second switch unit, the third switch unit, the fourth switch unit, and the fifth switch unit according to the identification result in an embodiment of the present invention.

[0018] The labels for the attached figures are as follows: 100. Multi-port fast charging control circuit; 10. AC / DC conversion unit; 20. Main control unit; 30. Step-down circuit unit; 40. First charging interface; 50. Second charging interface; 60. First switching unit; 70. Second switching unit; 80. Third switching unit; 90. Fourth switching unit; 110. Third charging interface; 120. Fifth switching unit; Q1, First NMOS transistor; R1, First resistor; Q2, Second NMOS transistor; R2, Second resistor; Q3, Third NMOS transistor; Q4, Fourth NMOS transistor; R3, Third resistor; Q5, Fifth NMOS transistor; Q6, Sixth NMOS transistor; R4, Fourth resistor; Q7, Seventh NMOS transistor; Q8, Eighth NMOS transistor; R5, Fifth resistor; U1, Protocol chip; U2, Buck chip; L1, Inductor; EC1, Energy storage capacitor; 200. Circuit board. Detailed Implementation

[0019] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0020] This invention provides a multi-port fast charging control circuit 100, such as... Figures 1 to 3 As shown, the multi-port fast charging control circuit 100 includes an AC / DC conversion unit 10, a main control unit 20, a step-down circuit unit 30, a first charging interface 40, a second charging interface 50, a first switching unit 60, a second switching unit 70, a third switching unit 80, and a fourth switching unit 90.

[0021] The first switching unit 60 is located between the voltage output terminal of the AC / DC conversion unit 10 and the first charging interface 40; the second switching unit 70 is located between the voltage output terminal of the AC / DC conversion unit 10 and the second charging interface 50.

[0022] The third switch unit 80 is located between the voltage output terminal of the step-down circuit unit 30 and the first charging interface 40; the fourth switch unit 90 is located between the voltage output terminal of the step-down circuit unit 30 and the second charging interface 50.

[0023] The voltage input terminal of the step-down circuit unit 30 is connected to the voltage output terminal of the AC-DC conversion unit 10.

[0024] The main control unit 20 is used to control the on / off state of the first charging interface 40 and the second charging interface 50 according to the device access status and required power, thereby controlling the AC / DC conversion unit 10 to directly supply power to the charging interface with the highest required power; and when the required power of the first charging interface 40 and the second charging interface 50 is the same, controlling the AC / DC conversion unit 10 to directly supply power to the charging interface that was connected first, and controlling the step-down circuit unit 30 to supply power to the other charging interface.

[0025] The multi-port fast charging control circuit 100 of this invention, by setting a first switch unit 60, a second switch unit 70, a third switch unit 80 and a fourth switch unit 90, works in conjunction with the main control unit 20 to flexibly control the on / off state of each switch unit according to the device access status and power demand of the first charging interface 40 and the second charging interface 50, and according to the access order of the two when the power demand is the same. This enables the charging interface with high power demand to be directly powered by the AC-DC conversion unit 10, while the other charging interface is powered by the step-down circuit unit 30. This application only needs to set one step-down circuit unit 30 to realize blind insertion fast charging and simultaneous fast charging of the first charging interface 40 and the second charging interface 50, which greatly reduces the use of large components such as control chips and inductors L1, simplifies the circuit structure, reduces the difficulty of layout and wiring, effectively reduces hardware costs, and prioritizes the use of AC-DC conversion unit 10 for power supply under any load conditions, resulting in lower losses and improved conversion efficiency.

[0026] Optionally, the first charging interface 40 and the second charging interface 50 can be Type-C interfaces, Lightning interfaces, etc. In a specific embodiment, both the first charging interface 40 and the second charging interface 50 adopt Type-C interfaces. The CC1 pin, CC2 pin, D+ pin, and D- pin of both are connected to the main control unit 20. The main control unit 20 detects the protocol and voltage requirements of the connected device through the first charging interface 40 and the second charging interface 50, and then controls the AC-DC conversion unit 10 and the step-down circuit unit 30 to output appropriate power.

[0027] like Figures 1 to 3 As shown, in an optional embodiment of this application, the multi-port fast charging control circuit 100 further includes a third charging interface 110. A fifth switching unit 120 is provided between the third charging interface 110 and the voltage output terminal of the step-down circuit unit 30. The main control unit 20 is also used to control the on / off state of the fifth switching unit 120 according to the device access status and power demand of the third charging interface 110, thereby controlling the step-down circuit unit 30 to supply power to the third charging interface 110.

[0028] Specifically, a third charging port 110 is added. The first charging port 40, the second charging port 50, and the third charging port 110 are still powered by a single AC / DC conversion unit 10 and a single step-down circuit unit 30. During operation, when only the third charging port 110 is connected to a device, the main control unit 20 independently controls the conduction and disconnection of the fifth switch unit 120 according to the device connection status and power demand of the third charging port 110, and controls the step-down circuit unit 30 to output appropriate power according to the feedback voltage. With this setup, there is no need to add an additional AC / DC conversion branch or a separate step-up or step-down circuit. The charging ports can be expanded simply by adding a fifth switch unit 120. While maintaining the original architecture of direct power supply for high-power interfaces and step-down power supply for low-power interfaces, it enables blind-plug fast charging of three or more devices, fully reuses the step-down circuit unit 30, avoids the addition of high-power magnetic components and control chips, simplifies the circuit layout, reduces the overall size, lowers hardware costs and wiring difficulty, and ensures the compatibility and power supply stability of multi-port blind-plug fast charging.

[0029] Optionally, the third charging interface 110 adopts a USB-A interface. The D+ and D- pins of the USB-A interface are connected to the main control unit 20. The main control unit 20 detects and identifies the device access status and power demand of the USB-A interface, and then controls the buck circuit unit 30 to output appropriate power.

[0030] In a specific implementation scenario, the first charging port 40 and the second charging port 50 both use Type-C interfaces, while the third charging port 110 uses a USB-A interface. The multi-port fast charging control circuit 100 operates as follows: When only the first charging port 40 is working, the main control unit 20 turns on the first switching unit 60 and turns off the other switching units. The main control unit 20 controls the AC / DC conversion unit 10 to output the voltage required by the first charging port 40, and the current flows to the first charging port 40 through the AC / DC conversion unit 10. When only the second charging port 50 is working, the main control unit 20 turns on the second switching unit 70 and turns off the other switching units. The main control unit 20 controls the AC / DC conversion unit 10 to output the voltage required by the second charging port 50, and the current flows to the second charging port 50 through the AC / DC conversion unit 10. When the first charging port 40 is connected first, the second charging port 50 is connected later, and the third charging port 110 is not connected, and the power demand of the first charging port 40 is greater than the power demand of the second charging port 50, the main control unit 20 turns on the first switching unit 60 and the fourth switching unit 90, turns off the other switching units, and controls the AC / DC conversion unit 110 to output the voltage required by the second charging port 50. The main control unit 20 outputs the voltage required by the first charging interface 40, controls the step-down circuit unit 30 to step down the voltage, and provides the required voltage for the second charging interface 50. When the first charging interface 40 is connected first, the second charging interface 50 is connected later, and the third charging interface 110 is not connected, and the power required by the first charging interface 40 is less than the power required by the second charging interface 50, the main control unit 20 turns on the second switch unit 70 and the third switch unit 80, turns off the remaining switch units, and controls the AC / DC conversion unit 10 to output the voltage required by the second charging interface 50, and controls the step-down circuit unit 30 to step down the voltage, and provides the required voltage for the first charging interface 40. When the first charging interface 40, the second charging interface 50 and the third charging interface 110 are all connected to the device, the switch unit corresponding to the one with the higher power requirement among the first charging interface 40 and the second charging interface 50 is turned on, the main control unit 20 controls the AC / DC conversion unit 10 to output the required voltage, and the remaining charging interfaces are powered by the step-down circuit unit 30.

[0031] like Figures 1 to 3 As shown, in an optional embodiment of this application, the main control unit 20 includes a protocol chip U1, and the step-down circuit unit 30 includes a step-down chip U2, an inductor L1, and an energy storage capacitor EC1; the first voltage regulation terminal FBO_C1 of the protocol chip U1 is connected to the AC / DC conversion unit 10, and its second voltage regulation terminal FBO_C2 is connected to the step-down chip U2; the step-down chip U2 is connected to the first terminal of the inductor L1; the second terminal of the inductor L1 is connected to the first terminal of the energy storage capacitor EC1, the third switching unit 80, and the fourth switching unit 90; the second terminal of the energy storage capacitor EC1 is grounded.

[0032] Specifically, the protocol chip U1 of the main control unit 20 is responsible for overall power supply control. Its first voltage regulation terminal FBO_C1 is connected to the AC / DC conversion unit 10, and its second voltage regulation terminal FBO_C2 is connected to the buck chip U2. It can feed back the power demand of the devices connected to the first charging interface 40, the second charging interface 50, and the third charging interface 110 to the buck chip U2 of the AC / DC conversion unit 10 and the buck circuit unit 30, controlling the output power of the AC / DC conversion unit 10 and the buck circuit unit 30 to precisely regulate the two power supply voltages. The buck circuit unit 30 uses the buck chip U2, inductor L1, and energy storage capacitor EC1 to form a complete buck branch. The buck chip U2 receives the regulation signal from the protocol chip U1 and works with inductor L1 and energy storage capacitor EC1 to achieve voltage reduction and ensure stable output voltage. The second terminal of inductor L1 serves as the voltage output terminal of the buck circuit unit 30, outputting a stable low voltage to provide another power source for the first charging interface 40 and the second charging interface 50.

[0033] Therefore, the core power supply of this application only requires a protocol chip U1 and a step-down chip U2 and their peripheral circuits. The overall circuit is simple and the power supply architecture is more cost-effective.

[0034] In a specific embodiment, the first voltage regulation terminal FBO_C1 of the protocol chip U1 can be connected to the AC / DC conversion unit 10 via an optocoupler.

[0035] like Figures 1 to 3 As shown, in an optional embodiment of this application, the first switching unit 60 includes a first NMOS transistor Q1 and a first resistor R1. The first resistor R1 is connected in series between the first NMOS transistor Q1 and the first control terminal of the main control unit 20. The drain of the first NMOS transistor Q1 is connected to the voltage output terminal of the AC / DC conversion unit 10, and its source is connected to the first charging interface 40. And / or, the second switching unit 70 includes a second NMOS transistor Q2 and a second resistor R2. The second resistor R2 is connected in series between the second NMOS transistor Q2 and the second control terminal of the main control unit 20. The drain of the second NMOS transistor Q2 is connected to the voltage output terminal of the AC / DC conversion unit 10, and its source is connected to the second charging interface 50.

[0036] Specifically, the first switching unit 60 uses a first NMOS transistor Q1 paired with a first resistor R1. The first resistor R1 is used for current limiting and voltage regulation to prevent excessive drive current from damaging the first NMOS transistor Q1. The drain of the first NMOS transistor Q1 is connected to the output terminal of the AC / DC conversion unit 10, and the source is connected to the first charging interface 40. Utilizing the low on-resistance and fast switching speed of the first NMOS transistor Q1, rapid on / off control of the power supply path is achieved. During operation, the main control unit 20 drives the first NMOS transistor Q1 to turn on or off through high and low level signals. When the power demand of the device connected to the first charging interface 40 is the highest, or when the power demand of the first charging interface 40 and the second charging interface 50 are the same, and the device is connected to the first charging interface 40 first, the main control unit 20 controls the first NMOS transistor Q1 to turn on and controls the AC / DC conversion unit 10 to output power according to the power demand of the device connected to the first charging interface 40, thus meeting the high-power fast charging requirements of the first charging interface 40. Compared to devices such as relays, the circuit structure of the first switching unit 60 is smaller and responds faster. Compared to complex drive circuit structures, it is more streamlined, achieving high-power direct supply path switching control with only a single first NMOS transistor Q1 and a first resistor R1. This simplifies layout and wiring, and reduces costs. Simultaneously, the first NMOS transistor Q1 has low conduction losses and high power supply efficiency, stably supporting high-current fast charging at the interface. Combined with the main control unit 20, it achieves precise and rapid power supply switching, simplifying the circuit and reducing costs while ensuring the stability and efficiency of power supply for multi-port fast charging.

[0037] The second switching unit 70 uses a second NMOS transistor Q2 paired with a second resistor R2. The second resistor R2 is used for current regulation to prevent excessive drive current from damaging the second NMOS transistor Q2. When the device connected to the second charging interface 50 has the highest power requirement, or when the power requirements of the second charging interface 50 and the first charging interface 40 are the same, and the device is connected to the second charging interface 50 first, the main control unit 20 controls the second NMOS transistor Q2 to be turned on and controls the AC / DC conversion unit 10 to output power according to the power requirement of the device connected to the second charging interface 50, thus meeting the high-power fast charging requirements of the second charging interface 50. The circuit structure of the second switching unit 70 is also simple, with easy layout and wiring, and low cost.

[0038] In other embodiments, the first switching unit 60 and the second switching unit 70 may also use PMOS transistors to connect or disconnect the path between the AC / DC conversion unit 10 and the first charging interface 40 and the second charging interface 50.

[0039] like Figures 1 to 3As shown, in an optional embodiment of this application, the third switching unit 80 includes a third NMOS transistor Q3, a fourth NMOS transistor Q4, and a third resistor R3; the source of the third NMOS transistor Q3 is connected to the source of the fourth NMOS transistor Q4; the drain of the third NMOS transistor Q3 is connected to the voltage output terminal of the buck circuit unit 30; the drain of the fourth NMOS transistor Q4 is connected to the second charging interface 50; the gate of the third NMOS transistor Q3 is connected to the gate of the fourth NMOS transistor Q4 and connected to the third control terminal of the main control unit 20 through the third resistor R3; and / or, the fourth switching unit 90 includes a fifth NMOS transistor Q5, a sixth NMOS transistor Q6, and a fourth resistor R4; the source of the fifth NMOS transistor Q5 is connected to the source of the sixth NMOS transistor Q6; the drain of the fifth NMOS transistor Q5 is connected to the voltage output terminal of the buck circuit unit 30; the drain of the sixth NMOS transistor Q6 is connected to the second charging interface 50; the gate of the fifth NMOS transistor Q5 is connected to the gate of the sixth NMOS transistor Q6 and connected to the fourth control terminal of the main control unit 20 through the fourth resistor R4.

[0040] Specifically, the third switching unit 80 employs two source-to-source NMOS transistors, Q3 and Q4, forming a back-to-back switching structure. During operation, the main control unit 20 outputs a level through the third control terminal, which drives the third NMOS transistors Q3 and Q4 to simultaneously turn on or off via the third resistor R3, thus connecting or disconnecting the power supply path between the buck circuit unit 30 and the first charging interface 40. The third switching unit 80 uses a source-to-source dual NMOS transistor structure, utilizing the NMOS transistor body diode to block reverse current, preventing voltage backflow from the first charging interface 40 side to the buck circuit unit 30, ensuring unidirectional controllable power supply. The third resistor R3 acts as a current-limiting buffer, preventing excessive drive current from the main control unit 20 from damaging the third NMOS transistors Q3 and Q4, while also improving switching stability. The aforementioned third switching unit 80 consists of only a few MOS transistors and resistors, resulting in a simple and compact structure that eliminates the need for complex driver chips, simplifying layout and wiring, and effectively reducing circuit size and hardware cost. Back-to-back NMOS transistors have low on-resistance and fast switching speed, which can meet the high current transmission requirements of fast charging, reduce conduction losses, and improve power supply efficiency.

[0041] Similarly, the fourth switching unit 90 uses the fifth NMOS transistor Q5 and the sixth NMOS transistor Q6 to form a back-to-back switching structure. During operation, the main control unit 20 outputs a level through the fourth control terminal, which drives the fifth NMOS transistor Q5 and the sixth NMOS transistor Q6 to simultaneously turn on or off via the fourth resistor R4, thus connecting or disconnecting the power supply path between the buck circuit unit 30 and the second charging interface 50. Utilizing its body diode characteristics, the fourth switching unit 90 only allows current to flow from the buck circuit unit 30 to the second charging interface 50, effectively preventing high voltage or reverse voltage backflow on the interface side and damage to the buck unit, ensuring unidirectional power supply safety. The fourth switching unit 90 has a simple and compact structure, requires no complex driver chip, and has simplified layout and wiring, effectively reducing circuit size and hardware cost.

[0042] like Figures 1 to 3 As shown, in an optional embodiment of this application, the fifth switching unit 120 includes a seventh NMOS transistor Q7, an eighth NMOS transistor Q8, and a fifth resistor R5; the source of the seventh NMOS transistor Q7 is connected to the source of the eighth NMOS transistor Q8; the drain of the seventh NMOS transistor Q7 is connected to the voltage output terminal of the buck circuit unit 30; the drain of the eighth NMOS transistor Q8 is connected to the third charging interface 110; the gate of the seventh NMOS transistor Q7 is connected to the gate of the eighth NMOS transistor Q8 and connected to the fifth control terminal of the main control unit 20 through the fifth resistor R5.

[0043] Specifically, the fifth switching unit 120 adopts a back-to-back structure with the sources of the seventh NMOS transistor Q7 and the eighth NMOS transistor Q8 connected together, and is connected to the main control unit 20 in series with the fifth resistor R5, forming an independent step-down power supply path. During operation, the main control unit 20 outputs a drive level through the fifth control terminal. After current limiting by the fifth resistor R5, it synchronously triggers the seventh NMOS transistor Q7 and the eighth NMOS transistor Q8 to turn on or off. At the moment of turn-on, the current flows from the output terminal of the step-down circuit unit 30, through the seventh NMOS transistor to the eighth NMOS transistor, and finally to the third charging interface 110, achieving stable power supply. The fifth switching unit 120 utilizes the body diode characteristics of the back-to-back MOS transistors to strictly block high voltage reverse flow on the interface side, prevent reverse voltage from damaging the step-down circuit unit 30, and ensure unidirectional controllable power supply and system safety. Its on-resistance is extremely low, and in conjunction with the current-limiting resistor, it can suppress drive spikes, significantly reducing conduction losses and improving power supply efficiency while supporting high-power fast charging. The overall circuit structure of the fifth switch unit 120 is extremely simple, which simplifies PCB layout and wiring, reduces overall size, effectively controls hardware costs, and enables efficient and safe expansion of the third charging interface 110, adapting to the modular expansion needs of multi-port fast charging systems.

[0044] This invention also provides a charger, such as... Figures 1 to 4As shown, the charger includes a circuit board 200 and a multi-port fast charging control circuit 100 as described above, the multi-port fast charging control circuit 100 being disposed on the circuit board 200. This charger incorporates the same structure and beneficial effects as the multi-port fast charging control circuit 100 in the foregoing embodiments. The structure and beneficial effects of the multi-port fast charging control circuit 100 have been described in detail in the foregoing embodiments and will not be repeated here.

[0045] This invention also provides a multi-port fast charging control method, implemented using the multi-port fast charging control circuit 100 described above. Figures 1 to 5 As shown, the multi-port fast charging control method includes the following steps: S101. Identify the device access status of the first charging interface 40 and the second charging interface 50 and the power requirement of each accessed device. S102. Based on the identification result, control the on / off state of the first switch unit 60, the second switch unit 70, the third switch unit 80 and the fourth switch unit 90, thereby controlling the AC / DC conversion unit 10 to directly supply power to the charging interface with the highest power requirement; and when the power requirements of the first charging interface 40 and the second charging interface 50 are the same, control the AC / DC conversion unit 10 to directly supply power to the charging interface that was connected first, and control the step-down circuit unit 30 to supply power to the other charging interface.

[0046] In step S101, the main control unit 20 polls the first charging interface 40 and the second charging interface 50 in real time, detects the electrical level and communication handshake signal of the first charging interface 40 and the second charging interface 50, quickly identifies whether there is a device connected to the first charging interface 40 and the second charging interface 50, and resolves the maximum power required by the connected device through protocol negotiation.

[0047] In a specific implementation scenario, when a user inserts a device such as a mobile phone, tablet, or laptop into the first charging port 40 or the second charging port 50, the main control unit 20 performs a fast charging protocol handshake with the connected device through the communication pins of the first charging port 40 or the second charging port 50. This identifies whether a device is actually connected to the port and obtains the device's supported fast charging level, rated voltage, current, and other required power information through protocol interaction. At the moment the device is connected or disconnected, the main control unit 20 simultaneously refreshes the status and updates the power parameters, sensing changes in the interface load in real time. By identifying the connection status and required power in real time, accurate data is provided for subsequent power supply path allocation, avoiding idle power consumption or power supply anomalies when no device is connected. Simultaneously, it ensures that different fast charging devices can be correctly identified when connected, guaranteeing that subsequent power supply strategies accurately match device needs, improving charging compatibility and response timeliness.

[0048] In step 102, the main control unit 20 performs a logical judgment based on the information obtained in step S101: if both the first charging interface 40 and the second charging interface 50 are connected, the switching unit between the charging interface with higher power demand and the AC / DC conversion unit 10 is selected first, and the AC / DC conversion unit 10 directly supplies power; if the power demand of the first charging interface 40 and the second charging interface 50 is the same, the direct power supply path between the charging interface connected to the device first and the AC / DC conversion unit 10 is connected first, while the step-down power supply path of the other charging interface is connected.

[0049] Therefore, by implementing the multi-port fast charging control method through the multi-port fast charging control circuit 100, only one step-down circuit unit 30 is needed to achieve simultaneous fast charging of the first charging interface 40 and the second charging interface 50. This significantly reduces the use of large components such as control chips and inductors L1, simplifies the circuit structure, reduces the difficulty of layout and wiring, effectively reduces hardware costs, and prioritizes the use of AC / DC conversion unit 10 for power supply under any load conditions, thereby improving conversion efficiency.

[0050] like Figures 1 to 6 As shown in the optional embodiment of this application, the specific steps for controlling the on / off states of the first switch unit 60, the second switch unit 70, the third switch unit 80, the fourth switch unit 90, and the fifth switch unit 120 based on the identification result include: S201. When only the first charging interface 40 or the second charging interface 50 is connected to the device, the corresponding first switching unit 60 or the second switching unit 70 is turned on, the other switching units are turned off, and the AC / DC conversion unit 10 is controlled to directly supply power to the first charging interface 40 or the second charging interface 50 connected to the device. S202. When both the first charging interface 40 and the second charging interface 50 are connected to the device, according to the power demand of the connected device, the switch unit between the charging interface with the highest power demand and the AC / DC conversion unit 10 is controlled to be turned on, and the switch unit between the other charging interface and the step-down circuit unit 30 is controlled to be turned on; if the power demand of the first charging interface 40 and the second charging interface 50 is the same, the switch unit between the charging interface connected to the device first and the AC / DC conversion unit 10 is turned on, and the switch unit between the other charging interface and the step-down circuit unit 30 is controlled to be turned on.

[0051] In one specific implementation scenario, the user first connects a laptop supporting high-power fast charging to the first charging port 40. The main control unit 20, recognizing the high power demand, controls the first switching unit 60 to conduct, allowing the AC / DC conversion unit 10 to directly provide fast charging. Then, when a mobile phone is plugged into the second charging port 50, the main control unit 20 detects that the phone's power demand is lower and controls the fourth switching unit 90 to conduct, allowing the step-down circuit unit 30 to power the phone, ensuring the laptop continues to fast charge at full power. Alternatively, if the user first connects the mobile phone to the first charging port 40, the main control unit 20, recognizing the power demand, controls the first switching unit 60 to conduct, allowing the AC / DC conversion unit 10 to directly provide fast charging. Then, when a laptop supporting high-power fast charging is plugged into the second charging port 50, the main control unit 20, recognizing the high power demand, controls the first switching unit 60 to disconnect and the second switching unit 70 and the third switching unit 80 to connect. This allows the AC / DC conversion unit 10 to directly power the laptop, while the step-down circuit unit 30 powers the mobile phone, improving conversion efficiency.

[0052] If both the first charging port 40 and the second charging port 50 are connected to devices such as mobile phones or laptops that require the same power, the AC / DC conversion unit 10 will be prioritized to supply power to the device that is connected first. Devices connected later will be powered through the step-down circuit unit 30. This ensures both the fast charging experience for the first device connected and stable charging at both ports simultaneously. In this scenario, there is no need for two independent step-down circuits; power distribution for multiple ports can be completed simply by switching between them. This satisfies the need for simultaneous fast charging of multiple devices while simplifying the circuit and reducing cost and size.

[0053] In optional embodiments of this application, such as Figures 1 to 3 As shown, the multi-port fast charging control circuit 100 also includes a third charging interface 110. A fifth switching unit 120 is provided between the third charging interface 110 and the voltage output terminal of the step-down circuit unit 30. The multi-port fast charging control method also includes the following steps: Identify the device connection status and power demand of the third charging port 110; Based on the identification results, the first switch unit 60, the second switch unit 70, the third switch unit 80, the fourth switch unit 90 and the fifth switch unit 120 are controlled to switch on and off, thereby controlling the AC-DC conversion unit 10 to directly supply power to the first charging interface 40 or the second charging interface 50 with the highest power demand, while the other charging interfaces share the power supply of the step-down circuit unit 30. If the power requirements of the first charging interface 40 and the second charging interface 50 are the same, the control AC / DC conversion unit 10 directly supplies power to the charging interface that is connected first, and the remaining charging interfaces share the power supply of the step-down circuit unit 30.

[0054] In a specific implementation scenario, the user first connects a laptop that supports high-power fast charging to the first charging port 40, then plugs a mobile phone into the second charging port 50, and finally connects a Bluetooth headset to the third charging port 110. The main control unit 20 identifies the connection status and power requirement of the three devices through protocol handshake, determines that the laptop connected to the first charging port 40 has the highest power requirement, and then controls the first switching unit 60 to conduct, so that the AC-DC conversion unit 10 directly provides high-power fast charging to the laptop; at the same time, it controls the fourth switching unit 90 and the fifth switching unit 120 to conduct, so that the mobile phone in the second charging port 50 and the Bluetooth headset in the third charging port 110 share the power supply of the step-down circuit unit 30. If the user subsequently plugs two phones with the same power requirements into the first charging port 40, the second charging port 50, and the smartwatch into the third charging port 110, the main control unit 20 detects that the two phones have the same power requirements. It then controls the AC / DC conversion unit 10 to directly power the phone that is connected first. The phone that is connected later and the smartwatch are powered together through the step-down circuit unit 30. While achieving simultaneous charging of the three ports, the fast charging performance of the higher power or the device connected first is given priority.

[0055] Therefore, by adding access status and power requirement identification for the third charging interface 110 to the existing dual-port control, the main control unit 20 synchronously acquires the device access status and power parameters of the first charging interface 40, the second charging interface 50, and the third charging interface 110 through protocol handshake and level detection. Then, based on the identification results, it comprehensively judges and controls the on / off state of each switching unit. In this way, while expanding the third charging interface 110, it still uses a single AC / DC conversion unit 10 and one step-down circuit unit 30, eliminating the need for additional multiple step-down circuits, significantly simplifying the circuit structure, reducing the number of components, and lowering the size, wiring difficulty, and hardware cost. Through intelligent allocation of the direct power supply channel, priority is given to ensuring the fast charging experience of high-power or first-connected devices, while the remaining interfaces share the step-down path. This achieves simultaneous fast charging of all three ports while ensuring reasonable utilization of power resources, balancing the practicality of multi-port blind-plug fast charging with circuit simplification, and improving charging compatibility and user experience.

[0056] It should be understood that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Those skilled in the art can modify the technical solutions described in the above embodiments, or make equivalent substitutions for some of the technical features; and all such modifications and substitutions should fall within the protection scope of the appended claims of the present invention.

Claims

1. A multi-port fast charging control circuit, characterized in that, It includes an AC / DC conversion unit, a main control unit, a step-down circuit unit, a first charging interface, a second charging interface, a first switching unit, a second switching unit, a third switching unit, and a fourth switching unit; The first switching unit is located between the voltage output terminal of the AC / DC conversion unit and the first charging interface; the second switching unit is located between the voltage output terminal of the AC / DC conversion unit and the second charging interface. The third switch unit is located between the voltage output terminal of the step-down circuit unit and the first charging interface; the fourth switch unit is located between the voltage output terminal of the step-down circuit unit and the second charging interface. The voltage input terminal of the step-down circuit unit is connected to the voltage output terminal of the AC-DC conversion unit; The main control unit is used to control the on / off state of the first charging interface, the second charging interface, the third switching unit, and the fourth switching unit according to the device access status and power demand of the first charging interface and the second charging interface, thereby controlling the AC / DC conversion unit to directly supply power to the charging interface with the highest power demand; and when the power demand of the first charging interface and the second charging interface are the same, controlling the AC / DC conversion unit to directly supply power to the charging interface that is connected first, and controlling the step-down circuit unit to supply power to the other charging interface.

2. The multi-port fast charging control circuit according to claim 1, characterized in that, The multi-port fast charging control circuit also includes a third charging interface. A fifth switching unit is provided between the third charging interface and the voltage output terminal of the step-down circuit unit. The main control unit is also used to control the on / off state of the fifth switching unit according to the device access status and power demand of the third charging interface, thereby controlling the step-down circuit unit to supply power to the third charging interface.

3. The multi-port fast charging control circuit according to claim 1, characterized in that, The main control unit includes a protocol chip, and the step-down circuit unit includes a step-down chip, an inductor, and an energy storage capacitor. The first voltage adjustment terminal of the protocol chip is connected to the AC / DC conversion unit, and its second voltage adjustment terminal is connected to the step-down chip. The step-down chip is connected to the first terminal of the inductor. The second terminal of the inductor is connected to the first terminal of the energy storage capacitor, the third switching unit, and the fourth switching unit. The second terminal of the energy storage capacitor is grounded.

4. The multi-port fast charging control circuit according to any one of claims 1-3, characterized in that, The first switching unit includes a first NMOS transistor and a first resistor. The first resistor is connected in series between the first NMOS transistor and the first control terminal of the main control unit. The drain of the first NMOS transistor is connected to the voltage output terminal of the AC-DC conversion unit, and its source is connected to the first charging interface. And / or, the second switching unit includes a second NMOS transistor and a second resistor, the second resistor being connected in series between the second NMOS transistor and the second control terminal of the main control unit, the drain of the second NMOS transistor being connected to the voltage output terminal of the AC / DC conversion unit, and its source being connected to the second charging interface.

5. The multi-port fast charging control circuit according to any one of claims 1-3, characterized in that, The third switching unit includes a third NMOS transistor, a fourth NMOS transistor, and a third resistor; the source of the third NMOS transistor is connected to the source of the fourth NMOS transistor; the drain of the third NMOS transistor is connected to the voltage output terminal of the buck circuit unit; the drain of the fourth NMOS transistor is connected to the second charging interface; the gate of the third NMOS transistor is connected to the gate of the fourth NMOS transistor and connected to the third control terminal of the main control unit through the third resistor. And / or, the fourth switching unit includes a fifth NMOS transistor, a sixth NMOS transistor, and a fourth resistor; the source of the fifth NMOS transistor is connected to the source of the sixth NMOS transistor; the drain of the fifth NMOS transistor is connected to the voltage output terminal of the buck circuit unit; the drain of the sixth NMOS transistor is connected to the second charging interface; the gate of the fifth NMOS transistor is connected to the gate of the sixth NMOS transistor and connected to the fourth control terminal of the main control unit through the fourth resistor.

6. The multi-port fast charging control circuit according to claim 2, characterized in that, The fifth switching unit includes a seventh NMOS transistor, an eighth NMOS transistor, and a fifth resistor; the source of the seventh NMOS transistor is connected to the source of the eighth NMOS transistor; the drain of the seventh NMOS transistor is connected to the voltage output terminal of the buck circuit unit; the drain of the eighth NMOS transistor is connected to the third charging interface; the gate of the seventh NMOS transistor is connected to the gate of the eighth NMOS transistor and connected to the fifth control terminal of the main control unit through the fifth resistor.

7. A charger, characterized in that, It includes a circuit board and a multi-port fast charging control circuit as described in any one of claims 1-6, wherein the multi-port fast charging control circuit is disposed on the circuit board.

8. A multi-port fast charging control method, characterized in that, The multi-port fast charging control method is implemented using the multi-port fast charging control circuit as described in any one of claims 1-6, and includes the following steps: Identify the device connection status and power demand of the first charging interface and the second charging interface; Based on the identification result, the first switch unit, the second switch unit, the third switch unit, and the fourth switch unit are controlled to switch on and off, thereby controlling the AC / DC conversion unit to directly supply power to the charging interface with the highest power demand; and when the power demand of the first charging interface and the second charging interface is the same, the AC / DC conversion unit is controlled to directly supply power to the charging interface that is connected first, and the step-down circuit unit is controlled to supply power to the other charging interface.

9. The multi-port fast charging control method according to claim 8, characterized in that, The specific steps for controlling the on / off states of the first, second, third, fourth, and fifth switch units based on the identification results include: When only the first charging interface or the second charging interface is connected to the device, the corresponding first switching unit or the second switching unit is turned on, the other switching units are turned off, and the AC / DC conversion unit is controlled to directly supply power to the first charging interface or the second charging interface connected to the device. When both the first charging interface and the second charging interface are connected to the device, the switching unit between the charging interface with the highest required power and the AC / DC conversion unit is controlled to be turned on according to the power demand of the connected device, and the switching unit between the other charging interface and the step-down circuit unit is controlled to be turned on; if the required power of the first charging interface and the second charging interface is the same, the switching unit between the charging interface connected to the device first and the AC / DC conversion unit is turned on, and the switching unit between the other charging interface and the step-down circuit unit is controlled to be turned on.

10. The multi-port fast charging control method according to claim 8, characterized in that, The multi-port fast charging control circuit further includes a third charging interface, and a fifth switching unit is provided between the third charging interface and the voltage output terminal of the step-down circuit unit. The multi-port fast charging control method further includes the following steps: Identify the device connection status and power requirement of the third charging interface; Based on the identification results, the first switch unit, the second switch unit, the third switch unit, the fourth switch unit, and the fifth switch unit are controlled to turn on and off, thereby controlling the AC / DC conversion unit to directly supply power to the first or second charging interface with the highest power demand, while the other charging interfaces share the power supply of the step-down circuit unit. If the first charging interface and the second charging interface have the same power requirements, the AC / DC conversion unit is controlled to directly supply power to the charging interface that is connected first, and the remaining charging interfaces share the power supply of the step-down circuit unit.

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