Current control circuit and power supply device

Abstract

The utility model discloses a current control circuit and a power supply device. The current control circuit comprises a switching circuit, a current induction circuit, a backward flowing current detection circuit and a control circuit. One end of the switching circuit is a current input end; the other end of the switching circuit is connected with one end of the current induction circuit, and the other end of the current induction circuit is a current output end; the current induction circuit is also connected with the backward flowing current detection circuit, and the backward flowing current detection circuit is configured to output a voltage signal when detecting that current flows into the current induction circuit from the current input end; one end of the control circuit is connected with the backward flowing current detection circuit, the other end of the control circuit is connected with the switching circuit, and the control circuit is configured to turn off the switching circuit when receiving the voltage signal. The power supply device can respond to the backward flowing current in time and prevent the backward flowing current from damaging the power supply device and the load. Therefore, the power supply device does not need to be provided with a diode to realize reverse current isolation, and the risk of reverse current is avoided while high current output precision is ensured.

Description

Technical Field

[0001] This application relates to the field of circuit control technologies, and particularly to a current control circuit and a power supply device. Background Art

[0002] For a power supply device with multiple outputs, current switches are provided at each output, enabling independent control of the power supply state of each branch, achieving fast circuit switching, power supply on demand, and dynamic adjustment, and adapting to different working modes or load requirements.

[0003] However, in the above circuit, good isolation cannot be achieved between each output, and reverse current injection of the output current may occur. In severe cases, it may even damage the power supply device or the load, causing safety accidents. Summary of the Utility Model

[0004] The main technical problem to be solved by this application is to provide a current control circuit and a power supply device, which can promptly respond to turn off the current when reverse current injection occurs in the power supply device, avoiding safety problems.

[0005] To solve the above technical problem, the technical solution adopted by this application is to provide a current control circuit. The overcurrent control circuit includes a switching circuit, a current sensing circuit, a reverse current injection detection circuit, and a control circuit; one end of the switching circuit is a current input end; the other end of the switching circuit is connected to one end of the current sensing circuit, and the other end of the current sensing circuit is a current output end; the current sensing circuit is further connected to the reverse current injection detection circuit, and the reverse current injection detection circuit is configured to output a voltage signal when detecting that current flows from the current input end into the current sensing circuit; one end of the control circuit is connected to the reverse current injection detection circuit, and the other end of the control circuit is connected to the switching circuit. The control circuit is configured to turn off the switching circuit when receiving the voltage signal.

[0006] In a possible implementation, the current sensing circuit includes a first resistor, a first end of the first resistor is connected to the switching circuit, and a second end of the first resistor is a current output end.

[0007] In a possible implementation, the current sensing circuit further includes: a first filtering circuit, the first filtering circuit includes a first inductor and a first capacitor, a first end of the first inductor is connected to the switching circuit, a second end of the first inductor is connected to a first end of the first capacitor, the second end of the first inductor is further connected to a first end of the first resistor, and a second end of the first capacitor is grounded; a second filtering circuit, the second filtering circuit includes a second inductor and a second capacitor, a first end of the second capacitor is connected to a second end of the first resistor, a second end of the second capacitor is grounded, the first end of the second capacitor is further connected to a first end of the second inductor, and a second end of the second inductor is a current output end.

[0008] In a possible implementation, the current sensing circuit further includes: a first negative clamping circuit, the first negative clamping circuit includes a first diode, a negative electrode of the first diode is connected to a second end of the first resistor, and a positive electrode of the first diode is grounded; a bidirectional clamping circuit, the bidirectional clamping circuit includes a bidirectional transient voltage suppression diode, a first end of the bidirectional transient voltage suppression diode is connected to the current output end, and a second end of the bidirectional transient voltage suppression diode is grounded.

[0009] In a possible implementation, the reverse current detection circuit includes: a current detection amplifier, the current detection amplifier includes a positive input pin, a negative input pin, and an output pin; wherein, the positive input pin is connected to a second end of the first resistor, and the negative input pin is connected to a first end of the first resistor; the output pin is connected to the control circuit.

[0010] In a possible implementation, the reverse current detection circuit further includes; a third filtering circuit, the third filtering circuit includes a second resistor, a third resistor, a fourth resistor, a third capacitor, a fourth capacitor, and a fifth capacitor; a first end of the second resistor is connected to a first end of the first resistor, and a second end of the second resistor is connected to the negative input pin of the current detection amplifier; a first end of the third resistor is connected to a second end of the first resistor, and a second end of the third resistor is connected to the positive input pin of the current detection amplifier; the current detection amplifier further includes a working current input pin, a first end of the fourth resistor is connected to the working current input pin, and a second end of the fourth resistor is connected to a first end of the first resistor; a first end of the third capacitor is connected to a second end of the second resistor, and a second end of the third capacitor is grounded; a first end of the fourth capacitor is connected to a second end of the third resistor, and a second end of the fourth capacitor is grounded; a first end of the fifth capacitor is connected to a first end of the fourth resistor, and a second end of the fifth capacitor is grounded.

[0011] In a possible implementation, the reverse current detection circuit further includes: a second negative clamping circuit, the second negative clamping circuit includes a second diode, the positive electrode of the second diode is grounded, and the negative electrode of the second diode is connected to the positive input pin of the current detection amplifier.

[0012] In a possible implementation, the control circuit includes: a switching transistor, the switching transistor includes a gate, a source, and a drain; wherein, the gate of the switching transistor is connected to the output pin of the current detection amplifier, one of the source and the drain of the switching transistor is connected to the switching circuit, and the other of the source and the drain of the switching transistor is grounded; preferably, the source of the switching transistor is connected to the switching circuit, and the drain of the switching transistor is grounded.

[0013] In a possible implementation, the control circuit further includes: an isolation circuit, the isolation circuit includes a third diode, the positive electrode of the third diode is connected to the output pin of the current detection amplifier, and the negative electrode of the third diode is connected to the gate of the switching transistor; a fourth filtering circuit, the fourth filtering circuit includes a sixth capacitor, a seventh capacitor, and a fifth resistor; wherein, the first end of the sixth capacitor is connected to the gate of the switching transistor, and the second end of the sixth capacitor is grounded; the first end of the seventh capacitor is connected to the source of the switching transistor, and the second end of the seventh capacitor is connected to the drain of the switching transistor; the first end of the fifth resistor is connected to the gate of the switching transistor, and the second end of the fifth resistor is grounded.

[0014] To solve the above technical problems, another technical solution adopted by this application is to provide a power supply device, and the power supply device includes the current control circuit described in any one of the above.

[0015] The beneficial effects of this application are: Different from the prior art, this application provides a current control circuit and a power supply device. The current control circuit is arranged on each current output branch of the power supply device, and the current control circuit is provided with a switching circuit, a current sensing circuit, a reverse current detection circuit, and a control circuit. Among them. When there is current flowing from the current output end into the current sensing circuit, the reverse current detection circuit can detect the reverse current and respond with an output voltage signal. The control circuit immediately turns off the switching circuit after receiving the voltage signal. The above can respond to the reverse current in a timely manner and avoid damage to the power supply device and the load caused by the reverse current. So that the power supply device does not need to be provided with a diode to achieve isolation of the reverse current, ensuring high current output accuracy while avoiding the risk of reverse current. Description of the Drawings

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

[0017] Figure 1 It is a structural schematic block diagram of an embodiment of the current control circuit of the present application;

[0018] Figure 2 It is Figure 1 a structural schematic diagram of a specific embodiment of the current control circuit;

[0019] Figure 3 It is Figure 2 a structural schematic diagram of the current sensing circuit in;

[0020] Figure 4 It is Figure 2 a structural schematic diagram of the backflow current detection circuit in;

[0021] Figure 5 It is Figure 2 a structural schematic diagram of the control circuit in.

[0022] Among them, 100, current control circuit; 10, switch circuit; 20, current sensing circuit; 30, control circuit; 40, backflow current detection circuit; 50, current input terminal; 60, current output terminal; L1, first inductor; L2, second inductor; C1, first capacitor; C2, second capacitor; C3, third capacitor; C4, fourth capacitor; C5, fifth capacitor; C6, sixth capacitor; C7, seventh capacitor; D1, first diode; D2, second diode; D3, third diode; Q, switching transistor; R1, first resistor; R2, second resistor; R3, third resistor; R4, fourth resistor; R5, fifth resistor; M, bidirectional transient voltage suppression diode; U1, current detection amplifier; U2, current switch management chip; IN-, negative input pin; IN+, positive input pin; V+, working current input pin; REF, reference potential pin; EN, enable terminal; R6, parameter resistor. Specific Embodiment

[0023] The following will clearly and completely describe the technical solutions in the embodiments of the present application in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, rather than all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0024] The terms used in the embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit the present application. The singular forms "a", "said", and "the" used in the embodiments of the present application and the appended claims are also intended to include the plural forms unless clearly indicated otherwise in the context. The term "plural" generally includes at least two, but does not exclude the case of including at least one.

[0025] It should be understood that the term "and / or" used herein is only a relational expression describing associated objects, indicating that three relationships may exist. For example, A and / or B may represent three cases: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " herein generally represents an "or" relationship between the associated objects before and after.

[0026] It should be understood that the terms "include", "comprise" or any other variant used herein are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, the elements defined by the statement "including..." do not exclude the existence of additional identical elements in the process, method, article or device including the said elements.

[0027] For a power supply device with multiple outputs, good isolation cannot be achieved between the outputs, and the situation of reverse current injection may occur. In severe cases, it may even damage the power supply device or the load, causing safety accidents.

[0028] Based on the above problems, the present application proposes a current control circuit and a power supply device, which are provided with a reverse current detection circuit. When the reverse current detection circuit detects reverse current, the control circuit turns off the switch circuit, which can respond to the reverse current in a timely manner and avoid damage to the power supply device and the load caused by the reverse current.

[0029] The following describes in detail a current control circuit and a power supply device provided by the present application with reference to the accompanying drawings and embodiments.

[0030] The present application provides a current control circuit. Please refer to Figure 1 And Figure 2 , Figure 1 is a schematic block diagram of the structure of an embodiment of the current control circuit of the present application; Figure 2 is Figure 1 a schematic structural diagram of a specific embodiment of the current control circuit. In some embodiments, the current control circuit 100 includes a switch circuit 10, a current sensing circuit 20, a reverse current detection circuit 40, and a control circuit 30.

[0031] Among them, the current control circuit 100 provided in this application can specifically be used to be set in a power supply device. The power supply device can be a power supply device for supplying power to medical devices or a welding machine power supply device, etc. Additionally, the power supply device can be a multi-output power supply device or a single-output power supply device, so as to promptly respond to turn off the current when current backflow occurs in the power supply device and avoid safety problems. Of course, in other embodiments, the current control circuit 100 can specifically also be set in any other reasonable electronic device that needs to supply current to a load, and this embodiment does not limit this.

[0032] One end of the switch circuit 10 is a current input terminal 50. The other end of the switch circuit 10 is connected to one end of the current sensing circuit 20, and the other end of the current sensing circuit 20 is a current output terminal 60. The current sensing circuit 20 is also connected to the backflow current detection circuit 40, and the backflow current detection circuit 40 is configured to output a voltage signal when detecting that current flows from the current input terminal 50 into the current sensing circuit 20. One end of the control circuit 30 is connected to the backflow current detection circuit 40, and the other end of the control circuit 30 is connected to the switch circuit 10. The control circuit 30 is configured to turn off the switch circuit 10 when receiving the voltage signal.

[0033] The switch circuit 10 can control the magnitude of the current to ensure the accuracy of the voltage output of the current control circuit 100. In this embodiment, the switch circuit 10 is specifically a current switch management chip U2. The current switch management chip U2 has an ISET (Current Sense Setting) pin, and a parameter resistor R6 is externally connected to the ISET pin of the current switch management chip U2. The maximum output current of the current switch management chip U2 can be set by adjusting the resistance value of the parameter resistor R6, thereby realizing the control of the output accuracy of the current control circuit 100. In some other embodiments, the switch circuit 10 can also be other types of switch circuits 10 such as a bipolar transistor switch. The bipolar transistor switch can control the current from the collector to the emitter by adjusting the current from the base to the emitter, thereby realizing the adjustment of the current magnitude.

[0034] The current sensing circuit 20 can specifically sense current by setting a sensing resistor (not labeled). In some other embodiments, the current sensing circuit 20 can also sense current by setting other components such as a current transformer, a Hall effect sensor, and a magnetoresistive sensor. When the reverse current detection circuit 40 detects that current flows into the current sensing circuit 20 from the current input terminal 50, it outputs a voltage signal. In this embodiment, the reverse current detection circuit 40 can specifically include a current detection amplifier U1. In some other embodiments, the reverse current detection circuit 40 can also detect the reverse current by setting an operational amplifier. Among them, the reverse current detection circuit 40 has a positive input pin IN+ and a negative input pin IN-. The positive input pin IN+ is connected to the current output terminal 60 of the current sensing circuit 20, and the negative input pin IN- is connected to the other end of the current sensing circuit 20. When there is a reverse current flowing into the current sensing circuit 20 from the current output terminal 60, the potential of the current output terminal 60 of the current sensing circuit 20 is higher than the potential of the other end. The reverse current detection circuit 40 has a differential voltage with the potential of the positive input pin IN+ higher than the potential of the negative input pin IN-. When this differential voltage exists, the reverse current detection circuit 40 detects the reverse current and can calculate the magnitude of the reverse current in combination with the resistance value of the sensing resistor in the current sensing circuit 20. After detecting the reverse current, the reverse current detection circuit 40 outputs a voltage signal to the control circuit 30. The function of the control circuit 30 is to turn off the switch circuit 10 after receiving the voltage signal. In this embodiment, the control circuit 30 specifically includes a switching transistor. In some other embodiments, the control circuit 30 can also achieve the function by setting a relay and a gate circuit chip.

[0035] The above current control circuit 100 is arranged on each current output branch of the power supply device. The current control circuit 100 is provided with a switch circuit 10, a current sensing circuit 20, a reverse current detection circuit 40, and a control circuit 30. Among them. When there is current flowing into the current sensing circuit 20 from the current output terminal 60, the reverse current detection circuit 40 can detect the reverse current and respond by outputting a voltage signal. The control circuit 30 immediately turns off the switch circuit 10 after receiving the voltage signal, can respond to the reverse current in a timely manner, and avoid damage to the power supply device and the load caused by the reverse current. The above enables the power supply device not to need to set a diode to achieve isolation of the reverse current, ensuring high current output accuracy while avoiding the risk of reverse current.

[0036] Please refer to Figure 3 , Figure 3 for Figure 2Schematic diagram of the structure of the in - current sensing circuit. In this embodiment, the current sensing circuit 20 includes a first resistor R1. The first end of the first resistor R1 is connected to the switch circuit 10, and the second end of the first resistor R1 is the current output terminal 60. Specifically, in this embodiment, the reverse - flowing current is sensed through a resistor. When the reverse - flowing current passes through the first resistor R1, a voltage drop will be generated across the first resistor R1. The potential of the second end of the first resistor R1 is greater than the potential of the first end of the first resistor R1. The reverse - flowing current detection circuit 40 detects the presence of the reverse - flowing current based on this voltage drop. In some other embodiments, the current sensing circuit 20 can also sense the current by setting other components such as current transformers, Hall - effect sensors, magnetoresistive sensors, etc.

[0037] Further, in some preferred embodiments, the current sensing circuit 20 further includes a first filtering circuit (not labeled) and a second filtering circuit (not labeled). The first filtering circuit includes a first inductor L1 and a first capacitor C1. The first end of the first inductor L1 is connected to the switch circuit 10, the second end of the first inductor L1 is connected to the first end of the first capacitor C1, the second end of the first inductor L1 is also connected to the first end of the first resistor R1, and the second end of the first capacitor C1 is grounded; the second filtering circuit includes a second inductor L2 and a second capacitor C2. The first end of the second capacitor C2 is connected to the second end of the first resistor R1, the second end of the second capacitor C2 is grounded, the first end of the second capacitor C2 is also connected to the first end of the second inductor L2, and the second end of the second inductor L2 is the current output terminal 60. Specifically, the first filtering circuit and the second filtering circuit are specifically inductance - capacitance filtering circuits, which are used to filter out the ripple voltage and high - frequency noise, so as to enable the current control circuit 100 to provide a more stable and smooth current output. In some other embodiments, the current sensing circuit 20 further includes a first negative - clamping circuit (not labeled) and a bidirectional clamping circuit (not labeled). The first negative - clamping circuit includes a first diode D1. The cathode of the first diode D1 is connected to the second end of the first resistor R1, and the anode of the first diode D1 is grounded; the bidirectional clamping circuit includes a bidirectional transient voltage suppression diode M. The first end of the bidirectional transient voltage suppression diode M is connected to the current output terminal 60, and the second end of the bidirectional transient voltage suppression diode M is grounded. Among them, the first negative - clamping circuit is arranged at the current output terminal 60 of the first resistor R1. The first negative - clamping circuit clamps the negative voltage to the ground, which is used to protect the components in the circuit from the influence of reverse - voltage spikes or negative voltages. The bidirectional clamping circuit clamps the current output terminal 60, which is used to ensure the stability of the current output and protect the subsequent circuit from the influence of over - voltage shocks.

[0038] Please refer to Figure 4 , Figure 4 for Figure 2Schematic diagram of the reverse injection current detection circuit. In this embodiment, the reverse injection current detection circuit 40 includes a current detection amplifier U1, and the current detection amplifier U1 includes a positive input pin IN+, a negative input pin IN−, and an output pin (not labeled); among them, the positive input pin IN+ is connected to the second end of the first resistor R1, and the negative input pin IN− is connected to the first end of the first resistor R1; the output pin is connected to the control circuit 30. Specifically, the current detection amplifier U1 detects the reverse injection current through the potential difference across the first resistor R1. In some other embodiments, the reverse injection current detection circuit 40 can also detect the reverse injection current by setting an operational amplifier.

[0039] In some embodiments, the reverse injection current detection circuit 40 further includes a third filter circuit (not labeled), and the third filter circuit includes a second resistor R2, a third resistor R3, a fourth resistor R4, a third capacitor C3, a fourth capacitor C4, and a fifth capacitor C5; the first end of the second resistor R2 is connected to the first end of the first resistor R1, and the second end of the second resistor R2 is connected to the negative input pin IN− of the current detection amplifier U1; the first end of the third resistor R3 is connected to the second end of the first resistor R1, and the second end of the third resistor R3 is connected to the positive input pin IN+ of the current detection amplifier U1; the current detection amplifier U1 further includes a working current input pin V+, the first end of the fourth resistor R4 is connected to the working current input pin V+, and the second end of the fourth resistor R4 is connected to the first end of the first resistor R1; the first end of the third capacitor C3 is connected to the second end of the second resistor R2, and the second end of the third capacitor C3 is grounded; the first end of the fourth capacitor C4 is connected to the second end of the third resistor R3, and the second end of the fourth capacitor C4 is grounded; the first end of the fifth capacitor C5 is connected to the first end of the fourth resistor R4, and the second end of the fifth capacitor C5 is grounded. Specifically, the third filter circuit is a resistor-capacitor filter circuit, and the third filter circuit is provided at the input end of the current detection amplifier U1. The current detection amplifier U1 is used to detect the reverse injection current according to the potential difference across the first resistor R1. The potential signals across the first resistor R1 are respectively input to the positive input pin IN+ and the negative input pin IN− of the current detection amplifier U1. The third filter circuit is used to filter out high-frequency noise in the potential signal to ensure the accuracy of the potential signal and ensure that the current detection amplifier U1 can accurately detect the reverse injection current. Among them, the current detection amplifier U1 further includes a reference potential pin REF and a ground pin, and both the reference potential pin REF and the ground pin are grounded.

[0040] Further, in some embodiments, the reverse injection current detection circuit 40 further includes a second negative clamping circuit (not labeled). The second negative clamping circuit includes a second diode D2. The positive electrode of the second diode D2 is grounded, and the negative electrode of the second diode D2 is connected to the positive input pin IN+ of the current detection amplifier U1. Specifically, the second negative clamping circuit is disposed at the input end of the current detection amplifier U1, and the second negative clamping circuit is used to avoid the influence of negative voltage spikes or overvoltage at the input end.

[0041] Please refer to Figure 5 , Figure 5 for Figure 2 a schematic structural diagram of the control circuit in. In some embodiments, the control circuit 30 includes a switching transistor Q. The switching transistor Q includes a gate (not labeled), a source (not labeled), and a drain (not labeled); wherein, the gate of the switching transistor Q is connected to the output pin of the current detection amplifier U1, one of the source and the drain of the switching transistor Q is connected to the switching circuit 10, and the other of the source and the drain of the switching transistor Q is grounded. Specifically, in this embodiment, the source of the switching transistor Q is connected to the switching circuit 10, and the drain of the switching transistor Q is grounded. In some other embodiments, it is also possible that the source of the switching transistor Q is grounded and the drain of the switching transistor Q is grounded. In this embodiment, the switching circuit 10 is a current switch management chip U2. The current switch management chip U2 also has an enable terminal EN. The source of the switching transistor Q is connected to the enable terminal EN of the current switch management chip U2. The gate of the switching transistor Q is the control terminal. As described above, after the gate of the switching transistor Q receives the voltage signal of the reverse injection current detection circuit 40, the source outputs a signal to the enable terminal EN of the switching circuit 10, and the switching circuit 10 is turned off accordingly to avoid the influence of the reverse injection current.

[0042] In some embodiments, the control circuit 30 further includes an isolation circuit (not labeled) and a fourth filtering circuit (not labeled). The isolation circuit includes a third diode D3. The positive electrode of the third diode D3 is connected to the output pin of the current detection amplifier U1, and the negative electrode of the third diode D3 is connected to the gate of the switching transistor Q; the fourth filtering circuit includes a sixth capacitor C6, a seventh capacitor C7, and a fifth resistor R5; wherein, the first end of the sixth capacitor C6 is connected to the gate of the switching transistor Q, and the second end of the sixth capacitor C6 is grounded; the first end of the seventh capacitor C7 is connected to the source of the switching transistor Q, and the second end of the seventh capacitor C7 is connected to the drain of the switching transistor Q; the first end of the fifth resistor R5 is connected to the gate of the switching transistor Q, and the second end of the fifth resistor R5 is grounded. Specifically, the fourth filtering circuit is a resistor-capacitor filtering circuit, and the fourth filtering circuit is used to filter out high-frequency noise in the signal.

[0043] Different from the prior art, the present application provides a current control circuit 100, which is provided with a switching circuit 10, a current sensing circuit 20, a backflow current detection circuit 40 and a control circuit 30. Among them. When there is a current flowing from the current output terminal 60 into the current sensing circuit 20, the backflow current detection circuit 40 can detect the backflow current and respond with an output voltage signal. The control circuit 30 immediately turns off the switching circuit 10 after receiving the voltage signal, can respond to the backflow current in a timely manner, and avoid damage to the power supply device and the load caused by the backflow current, so that the power supply device does not need to set a diode to achieve isolation of the backflow current, ensuring high current output accuracy while avoiding the risk of backflow current.

[0044] Correspondingly, the present application also proposes a power supply device, which includes the power supply control circuit described in any of the above embodiments.

[0045] The above are only the embodiments of the present application, and do not limit the patent scope of the present application. Any equivalent structure or equivalent principle transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied in other related technical fields, are similarly included in the patent protection scope of the present application.

Claims

1. A current control circuit, characterized in that, The current control circuit includes: A switching circuit, one end of the switching circuit being a current input terminal; A current sensing circuit, the other end of the switching circuit being connected to one end of the current sensing circuit, and the other end of the current sensing circuit being a current output terminal; A backflow current detection circuit, the current sensing circuit is also connected to the backflow current detection circuit, and the backflow current detection circuit is configured to output a voltage signal when it detects that current flows from the current input terminal into the current sensing circuit; A control circuit, one end of the control circuit is connected to the backflow current detection circuit, and the other end of the control circuit is connected to the switching circuit, and the control circuit is configured to turn off the switching circuit when it receives the voltage signal.

2. The current control circuit according to claim 1, wherein: The current sensing circuit includes a first resistor, a first end of the first resistor being connected to the switching circuit, and a second end of the first resistor being the current output terminal.

3. The current control circuit according to claim 2, wherein The current sensing circuit further includes: A first filter circuit, the first filter circuit includes a first inductor and a first capacitor, a first end of the first inductor is connected to the switching circuit, a second end of the first inductor is connected to a first end of the first capacitor, the second end of the first inductor is also connected to the first end of the first resistor, and a second end of the first capacitor is grounded; A second filter circuit, the second filter circuit includes a second inductor and a second capacitor, a first end of the second capacitor is connected to the second end of the first resistor, a second end of the second capacitor is grounded, the first end of the second capacitor is also connected to a first end of the second inductor, and a second end of the second inductor is the current output terminal.

4. The current control circuit according to claim 3, characterized in that, The current sensing circuit further includes: A first negative clamping circuit, the first negative clamping circuit includes a first diode, a negative electrode of the first diode is connected to the second end of the first resistor, and a positive electrode of the first diode is grounded; A bidirectional clamping circuit, the bidirectional clamping circuit includes a bidirectional transient voltage suppression diode, a first end of the bidirectional transient voltage suppression diode is connected to the current output terminal, and a second end of the bidirectional transient voltage suppression diode is grounded.

5. The current control circuit according to claim 2, wherein The backflow current detection circuit includes: A current detection amplifier, the current detection amplifier includes a positive input pin, a negative input pin, and an output pin; wherein, the positive input pin is connected to the second end of the first resistor, and the negative input pin is connected to the first end of the first resistor; the output pin is connected to the control circuit.

6. The current control circuit according to claim 5, wherein The backflow current detection circuit further includes; A third filter circuit, the third filter circuit includes a second resistor, a third resistor, a fourth resistor, a third capacitor, a fourth capacitor, and a fifth capacitor; A first end of the second resistor is connected to the first end of the first resistor, and a second end of the second resistor is connected to the negative input pin of the current detection amplifier; a first end of the third resistor is connected to the second end of the first resistor, and a second end of the third resistor is connected to the positive input pin of the current detection amplifier; The current detection amplifier further includes a working current input pin. The first end of the fourth resistor is connected to the working current input pin, and the second end of the fourth resistor is connected to the first end of the first resistor. The first end of the third capacitor is connected to the second end of the second resistor, and the second end of the third capacitor is grounded. The first end of the fourth capacitor is connected to the second end of the third resistor, and the second end of the fourth capacitor is grounded. The first end of the fifth capacitor is connected to the first end of the fourth resistor, and the second end of the fifth capacitor is grounded.

7. The current control circuit according to claim 6, characterized in that The reverse injection current detection circuit further includes: A second negative clamping circuit, which includes a second diode. The positive electrode of the second diode is grounded, and the negative electrode of the second diode is connected to the positive input pin of the current detection amplifier.

8. The current control circuit according to claim 5, wherein The control circuit includes: A switching transistor, which includes a gate, a source, and a drain. Wherein, the gate of the switching transistor is connected to the output pin of the current detection amplifier. One of the source and the drain of the switching transistor is connected to the switching circuit, and the other of the source and the drain of the switching transistor is grounded. The source of the switching transistor is connected to the switching circuit, and the drain of the switching transistor is grounded.

9. The current control circuit according to claim 8, wherein The control circuit further includes: An isolation circuit, which includes a third diode. The positive electrode of the third diode is connected to the output pin of the current detection amplifier, and the negative electrode of the third diode is connected to the gate of the switching transistor. A fourth filtering circuit, which includes a sixth capacitor, a seventh capacitor, and a fifth resistor. Wherein, the first end of the sixth capacitor is connected to the gate of the switching transistor, and the second end of the sixth capacitor is grounded. The first end of the seventh capacitor is connected to the source of the switching transistor, and the second end of the seventh capacitor is connected to the drain of the switching transistor. The first end of the fifth resistor is connected to the gate of the switching transistor, and the second end of the fifth resistor is grounded.

10. A power supply device, characterized in that, The power supply device includes the current control circuit according to any one of claims 1-9.

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