Charging circuit and charger

Abstract

The utility model provides a charging circuit and a charger, the charging circuit is applied to a charging device comprising at least two charging ports, and the charging circuit comprises a power supply circuit, a voltage stabilizing circuit and at least two output circuits. The power supply circuit is provided with a power supply end for outputting bus voltage. The voltage stabilizing circuit is coupled to the power supply circuit. And the at least two output circuits are coupled to the power supply end, receive the bus voltage output by the power supply end, are connected with the charging port and are used for acquiring the charging voltage of the charging port. Wherein the number of the output circuits is the same as that of the charging ports, and each output circuit is correspondingly connected with one charging port. The at least two output circuits are in communication connection, and one output circuit is coupled to the voltage stabilizing circuit so as to control the voltage stabilizing circuit to adjust the output bus voltage of the power supply circuit to be equal to the larger value of the charging voltage. Through the above mode, the charger provided by the utility model can solve the problem that a charger in the prior art generates heat seriously in the charging process.

Description

Technical Field

[0001] The utility model relates to the field of charging equipment, in particular to a charging circuit and a charger. Background Art

[0002] A charger is also called a charging device. It is often used to charge mobile phones, smart speakers, electric toothbrushes, new energy vehicles and other electrical devices in life or work. The charger has a charging circuit and a charging interface. The charging circuit is used to connect to the power source, and the charging interface is used to connect to the electrical device, so that the electrical device can be charged through the charger.

[0003] However, existing charging circuits often consume a lot of energy, and the consumed energy is converted into heat, causing the charger to generate severe heat during the charging process. Utility Model Content

[0004] The main technical problem solved by the utility model is to provide a charging circuit and a charger, which can improve the problem of serious heating of the charger in the prior art during the charging process.

[0005] In order to solve the above technical problems, in the first aspect, an embodiment of the utility model provides a charging circuit, which is applied to a charging device including at least two charging ports, and the charging circuit includes a power supply circuit, a voltage stabilizing circuit and at least two output circuits. The power supply circuit has a power supply end for outputting a bus voltage. The voltage stabilizing circuit is coupled to the power supply circuit. At least two output circuits are coupled to the power supply end, receive the bus voltage output by the power supply end, and are connected to the charging port to obtain the charging voltage of the charging port. Among them, the number of output circuits is the same as the number of charging ports, and each output circuit is respectively connected to a corresponding charging port. At least two output circuits are communicatively connected, and one of the output circuits is coupled to the voltage stabilizing circuit to control the voltage stabilizing circuit to adjust the output bus voltage of the power supply circuit to be equal to the larger value of the charging voltage.

[0006] In a second aspect, an embodiment of the utility model provides a charger, comprising the above-mentioned charging circuit.

[0007] Compared with the prior art, the beneficial effects of the utility model are: the output circuit directly obtains the charging voltage of the charging port, and controls the bus voltage output by the power supply circuit to be equal to the larger value of the charging voltage. Compared with the current bus voltage of most power supply circuits that is greater than the charging voltage, the step-down circuit is used to step down the output, which reduces the loss of the charger during the charging process, thereby improving the problem of severe heating of the charger during the charging process. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a circuit block diagram schematic diagram of a charging circuit in the prior art;

[0009] Figure 2 is a schematic diagram of a circuit block diagram of an embodiment of a charging circuit of the present application;

[0010] Figure 3 is a circuit diagram of an embodiment of a charging circuit of the present application;

[0011] Figure 4 It is a circuit block diagram of a partial structure of an embodiment of a charging circuit of the present application. DETAILED DESCRIPTION

[0012] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0013] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0014] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed", "set" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be directly connected or indirectly connected. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific circumstances.

[0015] The inventor of this application has found through research that the charger has a charging circuit, a power supply circuit and a charging interface. The charging circuit is connected to the power supply through the power supply circuit, and the charging interface is used to connect the electrical device, so that the electrical device can be charged through the charger. However, the existing charging circuit often consumes a lot of energy, and the consumed energy will be converted into heat, causing the charger to heat up seriously during the charging process. Specifically, if Figure 1 As shown, in order to enable the charging port of the charger to output different voltages or powers to match electrical devices of different specifications, a step-down circuit is often present in the charging circuit of the charger in the prior art. The step-down circuit causes energy loss and causes serious heating of the charger.

[0016] Chargers are common devices in our daily life and can be divided into wired chargers and wireless chargers. Wired chargers are chargers on the market that require a charging cable to connect to the device. They can convert direct current or alternating current into direct current that can charge the battery. They are widely used in consumer electronic products such as smartphones, tablets, notebooks, electric toothbrushes, wireless headphones, smart speakers, etc.

[0017] Typically, a wired charger includes a housing, a metal pin, a charging interface (such as a USB interface or a TYPE-C interface), and a mainboard assembly. The housing is usually made of insulating material. The metal pins can be used to access the power supply line. The charging interface can be connected to the electronic device via a charging cable. The mainboard assembly may include various electronic components and circuit boards, and be connected to the metal pins and the charging interface. According to one or more embodiments of the present application, the mainboard assembly may be integrated with a charging circuit.

[0018] The charging circuit is applied to a charging device including at least two charging ports, and the charging circuit includes a power supply circuit, a voltage stabilizing circuit and at least two output circuits. The power supply circuit has a power supply end for outputting a bus voltage. The voltage stabilizing circuit is coupled to the power supply circuit. At least two output circuits are coupled to the power supply end, receive the bus voltage output by the power supply end, and are connected to the charging port to obtain the charging voltage of the charging port. The number of output circuits is the same as the number of charging ports, and each output circuit is connected to a corresponding charging port. At least two output circuits are communicatively connected, and one of the output circuits is coupled to the voltage stabilizing circuit to control the voltage stabilizing circuit to adjust the output bus voltage of the power supply circuit to be equal to the larger value of the charging voltage.

[0019] See also Figure 2 and Figure 3 , Figure 2 is a circuit block diagram of an embodiment of a charging circuit of the present application, Figure 3 1 is a circuit diagram of an embodiment of a charging circuit of the present application. The charging circuit 10 of the present embodiment is applicable to a charger including multiple charging ports, and can be used to charge at least one external electrical device. The charging circuit 10 may include a power supply circuit 100, a voltage stabilizing circuit 200, and at least two output circuits 300. Specifically, the at least two output circuits 300 may be two or more output circuits 300.

[0020] The power supply circuit 100 is connected to an external power supply source and has a power supply terminal Vin for outputting a bus voltage, that is, the power supply circuit 100 provides the power supply terminal Vin. The voltage stabilizing circuit 200 is coupled to the power supply circuit 100, for example, the voltage stabilizing circuit 200 is connected to the power supply circuit 100. At least two output circuits 300 are coupled to the power supply terminal Vin to receive the bus voltage output by the power supply terminal Vin, for example, each output circuit 300 is connected to the power supply terminal Vin. At least two output circuits 300 are also connected to the charging port 330 and are used to obtain the charging voltage of the charging port 330. At least two output circuits 300 are communicatively connected, and one of the output circuits 300 is coupled to the voltage stabilizing circuit 200 to control the voltage stabilizing circuit 200 to adjust the output bus voltage of the power supply circuit 100 to be equal to the larger value of the charging voltage.

[0021] In this way, the charging port 330 and the power supply end Vin of the power supply circuit 100 produce a direct connection effect, which is beneficial to reduce power loss and reduce heat generation.

[0022] The number of charging ports 330 can be the same as that of the output circuits 300 and they can be connected one by one. That is, each output circuit 300 is connected to a corresponding charging port 330. For example, one of the charging ports 330 is marked as TYPE-C#1, and the charging request of the power-consuming device connected to TYPE-C#1 is 15V3A. Then the output circuit 300 controls the output voltage of the power supply circuit 100 to 15V through the voltage stabilizing circuit 200, which is equivalent to the output bus voltage of the power supply circuit 100 directly reaching TYPE-C#1 (commonly known as direct pass). In the prior art, Figure 1 As shown, the output circuit is detected by the single-chip microcomputer, which causes the output voltage of the power supply circuit to be higher than 15V. For example, if the output voltage of the power supply circuit is 17V, a step-down circuit needs to be set to reduce 17V to 15V. The operation of the step-down circuit causes power loss and increased heat generation of the charger. Therefore, the 15V direct pass can significantly save losses and improve efficiency compared to stepping down 17V to 15V through a step-down circuit, thereby reducing the temperature of the charger casing. In addition, since the number of devices used in this solution is reduced compared to the prior art, the charging circuit 10 will occupy less space, and the volume of the charger can be reduced accordingly.

[0023] Furthermore, when the charging circuit 10 includes a plurality of output circuits 300 , the plurality of output circuits 300 can be controlled by serial communication of a plurality of processing circuits 310 to meet the demand of charging different electrical devices at the same time.

[0024] Compared with the prior art, the beneficial effects of the present invention are: the output circuit 300 directly obtains the charging voltage of the charging port 330, and controls the bus voltage output by the power supply circuit 100 to be equal to the larger value of the charging voltage. Compared with the current bus voltage of most power supply circuits 100 being greater than the charging voltage, the step-down circuit is used to step down the output, thereby reducing the loss of the charger during the charging process, thereby improving the problem of severe heating of the charger during the charging process.

[0025] Optionally, see Figure 3 and Figure 4 Each output circuit 300 includes a processing circuit 310 and a regulating circuit 320. The first end of the processing circuit 310 is connected to the voltage stabilizing circuit 200, the second end of the processing circuit 310 is connected to the first end of the regulating circuit 320, and the second end of the regulating circuit 320 is connected to the charging port 330, so that the processing circuit 310 is connected to the charging port 330 through the regulating circuit 320, and the first end and the second end of the regulating circuit 320 are connected to the power supply circuit 100. The processing circuit 310 is used to generate a feedback signal according to the charging voltage obtained from the charging port 330, so as to control the voltage stabilizing circuit 200 to adjust the bus voltage of the output of the power supply circuit 100 to be equal to the charging voltage through the feedback signal. Further, the regulating circuit 320 is connected to the power supply terminal Vin.

[0026] That is, when a power device is connected to the charging port 330, the processing circuit 310 can obtain the charging voltage required by the power device through the charging port 330 and generate a feedback signal according to the charging voltage. The voltage stabilizing circuit 200 adjusts the bus voltage of the power supply circuit 100 after receiving the feedback signal.

[0027] Optionally, see Figure 3 and Figure 4 The regulating circuit 320 includes a first switch circuit 321, a second switch circuit 322 and an energy storage circuit 323. The first switch circuit 321 is coupled to the power supply terminal Vin, the second switch circuit 322 and the energy storage circuit 323 are connected in parallel and coupled between the first switch circuit 321 and the ground voltage, and the charging port 330 is coupled to the energy storage circuit 323; the processing circuit 310 is coupled to the first switch circuit 321 and the second switch circuit 322, and is used to control the on and off of the first switch circuit 321 and the second switch circuit 322.

[0028] Optionally, the energy storage circuit 323 includes an energy storage inductor L0 and an energy storage capacitor C0, the energy storage capacitor C0 is grounded, one end of the charging port 330 is coupled to a node between the energy storage capacitor C0 and the energy storage inductor L0, and the other end is grounded.

[0029] In this case, when the first switch circuit 321 remains turned on and the second switch circuit 322 remains turned off, the charging port 330 can be directly coupled to the power supply terminal Vin through the first switch circuit 321, so that the charging voltage output by the charging port 330 is equal to the bus voltage. That is, the processing circuit 310 controls the first switch circuit 321 to be turned on and the second switch circuit 322 to be turned off, so that the charging voltage output by the charging port 330 is equal to the bus voltage.

[0030] When the first switch circuit 321 and the second switch circuit 322 are periodically turned on and off, for example, when the first switch circuit 321 is turned on and the second switch circuit 322 is turned off, the power supply terminal Vin can supply power to the energy storage capacitor C0. When the first switch circuit 321 is turned off and the second switch circuit 322 is turned on, the energy storage capacitor C0 releases energy through the second switch circuit 322, thereby enabling the charging voltage of the charging port 330 to be less than the bus voltage. Further, by controlling the frequency and duty cycle of the first switch circuit 321 and the second switch circuit 322 being turned on and off, the charging voltage outputted by the charging port 330 can be further adjusted. That is, the processing circuit 310 controls the first switch circuit 321 and the second switch circuit 322 to be periodically turned on and off so that the charging voltage outputted by the charging port 330 is less than the bus voltage.

[0031] Optionally, the first switch circuit 321 may include a first switch tube Q1. The second switch circuit 322 may include a second switch tube Q2. A first end of the first switch tube Q1 is coupled to a power supply end Vin, a second end of the first switch tube Q1 is coupled to a first end of the second switch tube Q2, and a second end of the second switch tube Q2 is grounded. The processing circuit 310 is coupled to control ends of the first switch tube Q1 and the second switch tube Q2 to control the on and off of the first switch tube Q1 and the second switch tube Q2.

[0032] Among them, the first switch tube Q1 and the second switch tube Q2 can be MOS tubes. The control end of the first switch tube Q1 / the second switch tube Q2 can correspond to the gate of the MOS tube, and the first end and the second end correspond to the source and drain of the MOS tube. When the gate potential of the MOS tube changes (the voltage between the gate and the source changes), the source and the drain can be switched between the on state and the off state. The first switch circuit 321 is turned on, which means that the source and the drain of the first switch tube Q1 are in the on state, and the first switch circuit 321 is turned off, which means that the source and the drain of the first switch tube Q1 are in the off state. Similarly, the second switch circuit 322 is turned on, which means that the source and the drain of the second switch tube Q2 are in the on state, and the second switch circuit 322 is turned off, which means that the source and the drain of the second switch tube Q2 are in the off state.

[0033] Furthermore, the first switch tube Q1 and the second switch tube Q2 can be gallium nitride (GaN) MOS tubes. GaN is a third-generation semiconductor material. Compared with traditional Si semiconductor materials, it has better electron migration speed, small on-resistance, low loss and high energy conversion efficiency. Therefore, the gallium nitride MOS tube has a higher operating frequency and a higher frequency working environment. In addition, as a wide bandgap material (i.e., the bandgap is as high as 3.4eV), GaN has a higher breakdown voltage and can carry more power, making it more suitable as a high-power output material, thereby achieving lower switching losses and more efficient charging.

[0034] Optionally, the first switch circuit 321 includes a first switch tube Q1, a first resistor R1 and a first capacitor C1. The second switch circuit 322 includes a second switch tube Q2, a second resistor R2 and a second capacitor C2. The first resistor R1 and the first capacitor C1 are connected in series and coupled to both ends of the first switch tube Q1. The second resistor R2 and the second capacitor C2 are connected in series and coupled to both ends of the second switch tube Q2.

[0035] Generally, when the MOS tube is turned on, certain oscillations and spikes may occur, which may cause electromagnetic interference. The above phenomenon can be improved by setting the first resistor R1 and the first capacitor C1 (the second resistor R2 and the second capacitor C2), thereby improving electromagnetic compatibility.

[0036] Optionally, the charging circuit 10 further includes a third switch tube Q3 coupled between the charging port 330 and the regulating circuit 320 , and the processing circuit 310 is coupled to a control terminal of the third switch tube Q3 to control the on-off of the third switch tube Q3 .

[0037] Furthermore, the processing circuit 310 can also determine the charging protocol when the electrical device is connected to the charging port 330, for example, determine whether the charging protocol is specifically USB-PD protocol (USB Power Delivery), QC protocol (Quick Charge), FCP protocol (Fast Charger Protocol), SCP protocol (Super Charge Protocol) or VOOC protocol. When the charging protocols of the electrical device and the charger do not match, the third switch tube Q3 can be disconnected to reduce the possibility of damaging the charger or the electrical device.

[0038] Optionally, the voltage stabilizing circuit 200 includes a controllable precision voltage stabilizing source U1. The processing circuit 310 is coupled to a control terminal of the controllable precision voltage stabilizing source U1. The controllable precision voltage stabilizing source U1 adjusts the current of the voltage stabilizing circuit 200 in response to the feedback signal.

[0039] Among them, the controllable precision voltage regulator U1 can adopt the common TL431, and the feedback signal can be used as the input of the controllable precision voltage regulator U1. When the input voltage (the voltage of the feedback signal) increases, the current flowing through the controllable precision voltage regulator U1 will also increase accordingly.

[0040] Optionally, the voltage stabilizing circuit 200 further includes a photoelectric coupling element OC1. The photoelectric coupling element OC1 is coupled to the controllable precision voltage stabilizing source U1 to synchronously adjust the bus voltage when the current of the voltage stabilizing circuit 200 changes.

[0041] The photoelectric coupling element OC1 generally includes a light source and a photosensitive element. The light source can be connected in series with the controllable precision voltage regulator U1, and the photosensitive element can be connected to the power supply circuit 100. When the current increases, the light intensity emitted by the light source increases, thereby changing the resistance value of the photoresistor, thereby enabling the power supply circuit 100 to adaptively adjust its voltage. The power supply circuit 100 can adjust its voltage in a way that can be used in an existing AC-DC circuit or DC-DC circuit to adjust its output bus voltage, which is not specifically limited here.

[0042] Specifically, the voltage stabilizing circuit 200 may further include a first voltage-dividing resistor and a second voltage-dividing resistor coupled in series between the power supply terminal Vin and the ground voltage. The control terminal of the controllable precision voltage-stabilizing source U1 may be coupled to a node between the first voltage-dividing resistor and the second voltage-dividing resistor. In addition, the voltage stabilizing circuit may further include an overcurrent protection resistor coupled in series with the controllable precision voltage-stabilizing source U1 and the optocoupler element OC1.

[0043] Optionally, at least two output circuits 300 include two output circuits, the processing circuits 310 of the two output circuits respectively obtain the charging voltages of their respective charging ports 330, the processing circuits 310 of the two output circuits are communicatively connected, and one of the processing circuits 310 is coupled to the voltage stabilizing circuit 200 to generate a feedback signal according to the larger of the charging voltages of the two charging ports 330.

[0044] In this case, the charging circuit 10 can charge two electrical devices. In addition, as described above, each charging circuit 10 has a separate regulating circuit 320, and the two regulating circuits 320 can be in different working states. For example, the first switch circuit 321 of one remains on, and the first switch circuit 321 and the second switch circuit 322 of the other are periodically turned on and off, respectively, so that the two charging ports 330 can simultaneously meet the requirements of electrical devices with different powers.

[0045] In other words, when two electrical devices with different charging voltages are connected to two charging ports 330 respectively, the corresponding processing circuits 310 can obtain the required charging voltages respectively, and the processing circuits 310 can compare the two charging voltages, thereby determining the higher one, and output a feedback signal according to the higher one. After receiving the feedback signal, the voltage stabilizing circuit 200 causes the power supply circuit 100 to adjust the bus voltage outputted by the power supply circuit 100 to be equal to the higher one of the two charging voltages. At this time, for the charging port 330 outputting the higher charging voltage, the corresponding first switch circuit 321 can remain turned on, and for the charging port 330 outputting the lower charging voltage, the corresponding first switch circuit 321 and the second switch circuit 322 are periodically turned on and off under the control of the processing circuit 310.

[0046] In addition, when the charging voltages required by the two charging ports 330 are equal, the two first switch circuits 321 only need to remain in the on state.

[0047] At least two output circuits 300 include three output circuits, and the processing circuits 310 of the three output circuits respectively obtain the charging voltage of the respective charging ports 330. The processing circuits 310 of the output circuits are connected in communication. The three processing circuits 310 in the three output circuits can be connected in series in sequence. One of the processing circuits 310 is coupled to the voltage stabilizing circuit 200, and is used to generate a feedback signal according to the larger of the charging voltages of the three charging ports 330.

[0048] In this case, the charging circuit 10 can charge one electric device, two electric devices, or three electric devices.

[0049] When only one power-consuming device is coupled to one of the charging ports 330, the processing circuit 310 corresponding to the charging port 330 can obtain the required charging voltage, and then output a feedback signal according to the feedback voltage. After receiving the feedback signal, the voltage stabilizing circuit 200 can adjust the bus voltage output by the power supply circuit to be equal to the charging voltage. The processing circuit 310 controls the first switch circuit 321 corresponding to the charging port 330 to remain in the on state.

[0050] When three electrical devices with different charging voltages are coupled to different charging ports 330 respectively, the processing circuits 310 corresponding to the three charging ports 330 can obtain the required charging voltages respectively, and the processing circuits 310 can compare the three charging voltages to determine the highest one, and output a feedback signal according to the highest one. After receiving the feedback signal, the voltage stabilizing circuit 200 causes the power supply circuit 100 to adjust the bus voltage outputted by it to be equal to the highest one of the three charging voltages. At this time, for the charging port 330 outputting the highest charging voltage, the corresponding first switch circuit 321 can remain turned on. The first switch circuits 321 and the second switch circuits 322 corresponding to the other two charging ports 330 are periodically turned on and off under the control of their respective processing circuits 310. The two processing circuits 310 can respectively control the on-off frequency and duty cycle of the corresponding first switch circuits 321 and the second switch circuits 322 so that the two output ports output different charging voltages.

[0051] The above description is only an implementation method of the present utility model, and does not limit the patent scope of the present utility model. Any equivalent structure or equivalent process transformation made by using the contents of the specification and drawings of the present utility model, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present utility model.

Claims

1. A charging circuit, applied to a charger including at least two charging ports, characterized in that: include: A power supply circuit having a power supply terminal for outputting a bus voltage; A voltage stabilizing circuit, coupled to the power supply circuit; at least two output circuits, coupled to the power supply end, receiving the bus voltage output by the power supply end, and connected to the charging port, for obtaining the charging voltage of the charging port; wherein the number of the output circuits is the same as the number of the charging ports, and each of the output circuits is connected to one of the charging ports; The at least two output circuits are communicatively connected, wherein one of the output circuits is coupled to the voltage stabilizing circuit to control the voltage stabilizing circuit to adjust the output bus voltage of the power supply circuit to be equal to a larger value of the charging voltage.

2. The charging circuit according to claim 1, characterized in that: Each of the output circuits comprises a processing circuit and a regulating circuit, wherein a first end of the processing circuit is connected to the voltage stabilizing circuit, a second end of the processing circuit is connected to a first end of the regulating circuit, a second end of the regulating circuit is connected to the charging port, and the first end and the second end of the regulating circuit are connected to the power supply circuit; The processing circuit is used to generate a feedback signal according to the charging voltage obtained from the charging port, so as to control the voltage stabilizing circuit to adjust the bus voltage output by the power supply circuit to be equal to the larger value of the charging voltage through the feedback signal.

3. The charging circuit according to claim 2, characterized in that: The regulating circuit includes a first switch circuit, a second switch circuit and an energy storage circuit. The first switch circuit is coupled to the power supply end, the second switch circuit and the energy storage circuit are connected in parallel and coupled between the first switch circuit and the ground voltage, and the charging port is coupled to the energy storage circuit; The processing circuit is coupled between the first switch circuit and the second switch circuit, and is used to control the on and off of the first switch circuit and the second switch circuit.

4. The charging circuit according to claim 3, characterized in that: The energy storage circuit includes an energy storage inductor and an energy storage capacitor. The energy storage capacitor is grounded. One end of the charging port is coupled to a node between the energy storage capacitor and the energy storage inductor, and the other end is grounded.

5. The charging circuit according to claim 3 or 4, characterized in that: The first switch circuit includes a first switch tube, a first resistor and a first capacitor, and the second switch circuit includes a second switch tube, a second resistor and a second capacitor. The first end of the first switch tube is coupled to the power supply end, the second end of the first switch tube is coupled to the first end of the second switch tube, the second end of the second switch tube is grounded, the first resistor and the first capacitor are connected in series and coupled to the two ends of the first switch tube, the second resistor and the second capacitor are connected in series and coupled to the two ends of the second switch tube, The processing circuit is coupled to the control ends of the first switch tube and the second switch tube to control the on and off of the first switch tube and the second switch tube.

6. The charging circuit according to claim 2, characterized in that: The charging circuit also includes a third switch tube coupled between the charging port and the regulating circuit, and the processing circuit is coupled to a control end of the third switch tube to control the on and off of the third switch tube.

7. The charging circuit according to claim 2, characterized in that: The at least two output circuits include three output circuits, and the processing circuits of the three output circuits respectively obtain the charging voltage of the respective charging ports. The processing circuits of the three output circuits are communicatively connected, and one of the processing circuits of the three output circuits is coupled to the voltage stabilizing circuit. The three processing circuits of the three output circuits are connected in series in sequence, and the processing circuit connected to the voltage stabilizing circuit is used to generate the feedback signal according to the larger of the charging voltages of the three charging ports.

8. The charging circuit according to claim 2, characterized in that: The voltage stabilizing circuit includes a controllable precision voltage stabilizing source. The processing circuit is coupled to a control terminal of the controllable precision voltage stabilizing source. The controllable precision voltage stabilizing source adjusts the current of the voltage stabilizing circuit in response to the feedback signal.

9. The charging circuit according to claim 8, characterized in that: The voltage stabilizing circuit further includes a photoelectric coupling element, which is coupled to the controllable precision voltage stabilizing source to synchronously adjust the bus voltage when the current of the voltage stabilizing circuit changes.

10. A charger, characterized in that: The charging circuit comprises the charging circuit according to any one of claims 1 to 9.

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