Power supply overcurrent protection circuit, power supply overcurrent protection device and vehicle

Abstract

The invention provides a power supply overcurrent protection circuit, a power supply overcurrent protection device and a vehicle, and relates to the technical field of electronics. The power supply overcurrent protection circuit comprises a current detection unit, a comparison unit, a controllable power supply switch unit and an overcurrent recovery control unit, wherein the overcurrent recovery control unit is configured to generate an overcurrent recovery control instruction; the over-current recovery control unit is used for detecting the output level of the comparison unit, determining over-current recovery time through an over-current recovery control instruction when the output level is a low level, and controlling the comparison unit to output a high level when the over-current recovery time is reached so as to control the controllable power supply switch unit to be closed through the comparison unit. According to the invention, overcurrent protection is carried out after overcurrent occurs in the power supply circuit, and power is supplied to the load again when the overcurrent recovery time is up, so that the power supply safety and stability of the power supply circuit are improved.

Description

Technical Field

[0001] This application relates to the field of electronic technology, and more specifically, to a power supply overcurrent protection circuit, a power supply overcurrent protection device, and a vehicle. Background Technology

[0002] With the rapid advancement of electronic technology, the safety performance of power supply devices has increasingly become a core concern in design and application. Especially in the field of electric vehicles, the safety of the power supply system directly affects the reliability of the entire vehicle and the safety of users; its importance is self-evident. During the power supply process, current limiting technology is a core technology for ensuring safety performance.

[0003] However, traditional overcurrent protection circuits typically only restore the circuit by disconnecting or reducing the load after triggering overcurrent protection, resulting in poor circuit adaptability and affecting the safety and stability of the power supply circuit. Summary of the Invention

[0004] The purpose of this application is to provide a power supply overcurrent protection circuit, a power supply overcurrent protection device, and a vehicle, so as to perform overcurrent protection after an overcurrent occurs in the power supply circuit, and to restore power to the load after the overcurrent recovery time, thereby improving the power supply safety and stability of the power supply circuit.

[0005] In a first aspect, embodiments of this application provide a power supply overcurrent protection circuit, which includes a current detection unit, a comparison unit, a controllable power supply switch unit, and an overcurrent recovery control unit. The overcurrent recovery control unit is configured to generate an overcurrent recovery control command. The current detection unit detects the current signal of the power supply circuit, converts the current signal into a voltage signal, and outputs it to the comparison unit. The comparison unit determines whether the power supply circuit is in an overcurrent state based on the voltage signal. If the power supply circuit is determined to be in an overcurrent state, the comparison unit outputs a low level and controls the controllable power supply switch unit to open. The overcurrent recovery control unit detects the output level of the comparison unit, and if the output level is low, determines the overcurrent recovery time through the overcurrent recovery control command. Upon reaching the overcurrent recovery time, the comparison unit outputs a high level, thereby controlling the controllable power supply switch unit to close.

[0006] In this embodiment, a comparison unit determines whether the power supply circuit is in an overcurrent state. If the power supply circuit is determined to be in an overcurrent state, a low level is output to disconnect the controllable power supply switch unit, putting the power supply circuit into overcurrent protection mode, thereby preventing circuit damage and improving the overall safety of the circuit. Furthermore, by setting an overcurrent recovery control unit, the power supply circuit can resume power supply to the load after overcurrent protection occurs and the overcurrent recovery time is satisfied, improving the power supply safety and stability of the power supply circuit.

[0007] In some embodiments, the current detection unit includes a first resistor R1, a second resistor R2, a third resistor R3, a first capacitor C1, and a current detection chip U1; the positive input terminal of the current detection chip U1 is connected to the first end of the first resistor R1, and the negative input terminal of the current detection chip U1 is connected to the first end of the second resistor R2; the output terminal of the current detection chip U1 is connected to the first end of the third resistor R3; the second end of the first resistor R1 is connected to the second end of the second resistor R2; the first end of the first capacitor C1 is connected to the second end of the third resistor R3, and the second end of the first capacitor C1 is grounded.

[0008] In this embodiment, the voltage across the first resistor R1 and the second resistor R2 is accurately measured by the current detection chip U1, and high-frequency noise is filtered out by the third resistor R3 and the first capacitor C1, making the output voltage smoother and more stable, thereby improving the accuracy of the comparison unit and avoiding false triggering or misjudgment.

[0009] In some embodiments, the overcurrent recovery control unit includes a first transistor Q3, a fourth resistor R4, and a control port; the control port is configured to generate an overcurrent recovery control command; the collector of the first transistor Q3 is connected to the first terminal of the first capacitor C1, the emitter of the first transistor Q3 is grounded, and the base of the first transistor Q3 is connected to the first terminal of the fourth resistor R4; the first terminal of the fourth resistor R4 is connected to the control port, and the second terminal of the fourth resistor R4 is grounded.

[0010] This application embodiment generates an overcurrent recovery control command at the control port, so that after overcurrent protection occurs and the overcurrent recovery time is met, power is restored to the load. This provides a logic-controllable overcurrent latching and recovery mechanism, which improves the power supply safety and stability of the power supply circuit without adding complex components.

[0011] In some embodiments, the comparison unit includes a comparator U2 and a voltage divider element; the first end of the voltage divider element is connected to the negative input end of the current detection chip U1; the positive power supply end of the comparator U2 is connected to the positive power supply input end of the power supply circuit, the negative power supply end of the comparator U2 is grounded, the negative input end of the comparator U2 is connected to the first end of the first capacitor C1, the positive input end of the comparator U2 is connected to the reference voltage, and the output end of the comparator U2 is connected to the second end of the voltage divider element; the voltage divider element is used to clamp the voltage at the output end of the current detection chip U1 to a lockout voltage when the output of the comparator U2 is low, wherein the lockout voltage is greater than the reference voltage of the comparator.

[0012] In this embodiment, when the comparator U2 outputs a low level, the voltage at the output of the current detection chip U1 is clamped to a lockout voltage by a voltage divider element, so that the power supply circuit is always in an overcurrent protection state. Even if the load is disconnected, the power supply circuit cannot resume output, thereby improving the safety of the power supply circuit.

[0013] In some embodiments, the voltage divider element includes a fifth resistor R5, a sixth resistor R7, a first diode D1, and a second diode D2; the output terminal of comparator U2 is connected to the cathodes of the first diode D1 and the second diode D2, respectively; the anode of the first diode D1 is connected to the first terminal of the fifth resistor R5; the anode of the second diode D2 is connected to the first terminal of the sixth resistor R7; the second terminal of the fifth resistor R5 is connected to the first terminal of the second resistor R2; and the second terminal of the sixth resistor R7 is connected to the controllable power supply switch unit.

[0014] In this embodiment, a resistor-diode voltage divider network is used to achieve the voltage divider function with very few components, reducing circuit complexity and improving versatility.

[0015] In some embodiments, the controllable power supply switch unit includes a seventh resistor R6, an eighth resistor R8, a ninth resistor R9, a second transistor Q2, and a MOSFET Q1; the source of the MOSFET Q1 is connected to the second terminal of the first resistor R1, the first terminal of the seventh resistor R6, the emitter of the second transistor Q2, and the first terminal of the eighth resistor R8; the gate of the MOSFET Q1 is connected to the collector of the second transistor Q2, the second terminal of the eighth resistor R8, and the first terminal of the ninth resistor R9; the drain of the MOSFET Q1 is connected to the positive output terminal of the power supply circuit; the second terminal of the seventh resistor R6 is connected to the second terminal of the sixth resistor R7 and the base of the second transistor Q2; the second terminal of the ninth resistor R9 is grounded.

[0016] In this embodiment, a high-side, low-power, single-signal controlled electronic switch is constructed using a transistor, a MOSFET, and three resistors. This switch is compatible with the preceding current detection, comparator, and voltage divider network, providing a simple, reliable, and extremely low-cost switch drive circuit for the entire circuit.

[0017] In some embodiments, MOSFET Q1 is a high-side switch.

[0018] This application embodiment, by setting an extremely high-side switch, makes the power supply overcurrent protection circuit suitable for scenarios with high requirements for safety and anti-interference (such as automotive electronics).

[0019] In some embodiments, the power supply overcurrent protection circuit further includes a second capacitor C2; the drain of the MOSFET Q1 is connected to the first terminal of the second capacitor C2, and the second terminal of the second capacitor C2 is grounded.

[0020] In this embodiment, a second capacitor C2 is connected between the drain of the MOSFET Q1 and ground for filtering, preventing noise from being transmitted to the load and improving the quality of the output signal.

[0021] Secondly, embodiments of this application provide a power supply overcurrent protection device, which includes the power supply overcurrent protection circuit of any embodiment of the first aspect.

[0022] Thirdly, embodiments of this application provide a vehicle that includes a power supply overcurrent protection circuit according to any embodiment of the first aspect.

[0023] Other features and advantages of this application will be set forth in the following description and will be apparent in part from the description or may be learned by practicing embodiments of this application. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of a power supply overcurrent protection circuit provided in an embodiment of this application; Figure 2 A schematic diagram of an overcurrent recovery control provided in an embodiment of this application; Figure 3 A circuit diagram of a power supply overcurrent protection circuit provided in an embodiment of this application.

[0026] icon: 10-Power supply overcurrent protection circuit, 101-Current detection unit, 102-Comparison unit, 103-Controllable power supply switch unit, 104-Overcurrent recovery control unit, R1-First resistor, R2-Second resistor, R3-Third resistor, C1-First capacitor, U1-Current detection chip, Q3-First transistor, R4-Fourth resistor, U2-Comparator, R5-Fifth resistor, R7-Sixth resistor, D1-First diode, D2-Second diode, R6-Seventh resistor, R8-Eighth resistor, R9-Ninth resistor, Q2-Second transistor, Q1-MOS transistor, C2-Second capacitor. Detailed Implementation

[0027] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0028] It should be noted that all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0029] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0030] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0031] Figure 1 This is a schematic diagram of a power supply overcurrent protection circuit provided in an embodiment of this application, as shown below. Figure 1 As shown, the power supply overcurrent protection circuit 10 includes a current detection unit 101, a comparison unit 102, a controllable power supply switch unit 103, and an overcurrent recovery control unit 104. The overcurrent recovery control unit 104 is configured to generate an overcurrent recovery control command. The current detection unit 101 detects the current signal of the power supply circuit, converts the current signal into a voltage signal, and outputs it to the comparison unit 102. The comparison unit 102 determines whether the power supply circuit is in an overcurrent state based on the voltage signal. If the power supply circuit is determined to be in an overcurrent state, it outputs a low level and controls the controllable power supply switch unit 103 to open. The overcurrent recovery control unit 104 detects the output level of the comparison unit 102, and if the output level is low, it determines the overcurrent recovery time through the overcurrent recovery control command. Upon reaching the overcurrent recovery time, it controls the comparison unit 102 to output a high level, thereby controlling the controllable power supply switch unit 103 to close.

[0032] In practice, the positive input terminal of the power supply circuit is connected to ground with voltage, and the positive output terminal is connected to ground with the load.

[0033] When the power supply circuit is working normally, the current detection unit 101 maintains current detection of the power supply circuit, converts the detected current signal into a voltage signal, and outputs the voltage signal to the comparison unit 102.

[0034] After receiving the voltage signal, the comparison unit 102 compares the voltage signal with the reference voltage stored in the comparison unit to determine whether the power supply circuit is in an overcurrent state.

[0035] If the voltage value of the voltage signal is greater than the reference voltage, the comparison unit 102 determines that the power supply circuit is in an overcurrent state and controls the controllable power supply switch unit 103 to open, so as to cut off the power supply to the load, that is, disconnect the power supply output, and realize timely overcurrent protection.

[0036] The overcurrent recovery control unit 104 is equipped with a timer or a microcontroller, wherein the timer or microcontroller integrates a timing program, which generates overcurrent recovery control instructions.

[0037] Figure 2 This is a schematic diagram of an overcurrent recovery control provided in an embodiment of this application, as shown below. Figure 2 As shown, the overcurrent recovery control unit 104 is used to detect the output level of the comparison unit 102 in real time. When the overcurrent recovery control unit 104 detects that the output level of the comparison unit 102 is low, the timer module or the microcontroller program counts the time, and after the overcurrent recovery time is reached, an overcurrent recovery control command is generated. At this time, the control port outputs a high level, thereby controlling the comparison unit 102 to output a high level, so as to control the controllable power supply switch unit 103 to close through the comparison unit 102.

[0038] In this embodiment, a comparison unit determines whether the power supply circuit is in an overcurrent state. If the power supply circuit is determined to be in an overcurrent state, a low level is output to disconnect the controllable power supply switch unit, putting the power supply circuit into overcurrent protection mode, thereby preventing circuit damage and improving the overall safety of the circuit. Furthermore, by setting an overcurrent recovery control unit, the power supply circuit can resume power supply to the load after overcurrent protection occurs and the overcurrent recovery time is satisfied, improving the power supply safety and stability of the power supply circuit.

[0039] Figure 3 A circuit diagram of a power supply overcurrent protection circuit provided in an embodiment of this application is shown below. Figure 3 As shown, the current detection unit includes a first resistor R1, a second resistor R2, a third resistor R3, a first capacitor C1, and a current detection chip U1.

[0040] The positive input terminal of the current detection chip U1 is connected to the first end of the first resistor R1, and the negative input terminal of the current detection chip U1 is connected to the first end of the second resistor R2. The output terminal of the current detection chip U1 is connected to the first end of the third resistor R3. The second end of the first resistor R1 is connected to the second end of the second resistor R2. The first end of the first capacitor C1 is connected to the second end of the third resistor R3, and the second end of the first capacitor C1 is grounded.

[0041] In the specific implementation process, the first resistor R1 and the second resistor R2 are used together to generate voltage at the positive and negative input terminals of the current detection chip U1, so as to convert the current signal in the power supply circuit into a voltage signal.

[0042] The current detection chip U1 amplifies the voltage signals from the positive and negative input terminals proportionally and outputs them from its output terminal to the third resistor R3. The current flowing through the third resistor R3 charges the first capacitor C1. Then, the voltage of the first capacitor is output to the comparison unit 102 for overcurrent detection.

[0043] In this embodiment, the voltage across the first resistor R1 and the second resistor R2 is accurately measured by the current detection chip U1, and high-frequency noise is filtered out by the third resistor R3 and the first capacitor C1, making the output voltage smoother and more stable, thereby improving the accuracy of the comparison unit and avoiding false triggering or misjudgment.

[0044] Please continue reading Figure 3 The overcurrent recovery control unit includes a first transistor Q3, a fourth resistor R4, and a control port; the control port is configured to generate overcurrent recovery control commands. In this configuration, the collector of the first transistor Q3 is connected to the first terminal of the first capacitor C1, the emitter of the first transistor Q3 is grounded, and the base of the first transistor Q3 is connected to the first terminal of the fourth resistor R4. The first terminal of the fourth resistor R4 is connected to the control port, and the second terminal of the fourth resistor R4 is grounded.

[0045] In the actual implementation process, a timer or microcontroller is set in the control port to generate overcurrent recovery control instructions through the timer program in the timer or microcontroller.

[0046] After the overcurrent recovery time is reached, the control port outputs a high level, turning on the first transistor Q3. The first capacitor C1 discharges through the first transistor Q3, causing the voltage output to the comparator unit 102 to be less than the reference voltage, thus causing the comparator unit 102 to output a high level. After the comparator unit 102 outputs a high level, it controls the controllable power supply switch unit 103 to close, continuing to supply power to the load. The first transistor Q3 is an NPN transistor.

[0047] This application embodiment generates an overcurrent recovery control command at the control port, so that after overcurrent protection occurs and the overcurrent recovery time is met, power is restored to the load. This provides a logic-controllable overcurrent latching and recovery mechanism, which improves the power supply safety and stability of the power supply circuit without adding complex components.

[0048] Please continue reading Figure 3 The comparison unit includes comparator U2 and voltage divider elements.

[0049] The voltage divider element has its first terminal connected to the negative input terminal of the current detection chip U1; the positive power supply terminal of the comparator U2 is connected to the positive power supply input terminal of the power supply circuit, the negative power supply terminal of the comparator U2 is grounded, the negative input terminal of the comparator U2 is connected to the first terminal of the first capacitor C1, the positive input terminal of the comparator U2 is connected to the reference voltage, and the output terminal of the comparator U2 is connected to the second terminal of the voltage divider element. The voltage divider element is used to clamp the voltage at the output terminal of the current detection chip U1 to the lockout voltage when the output of the comparator U2 is low, wherein the lockout voltage is greater than the reference voltage of the comparator.

[0050] The voltage divider includes a fifth resistor R5, a sixth resistor R7, a first diode D1, and a second diode D2. The output of comparator U2 is connected to the cathodes of the first diode D1 and the second diode D2, respectively. The anode of the first diode D1 is connected to the first terminal of the fifth resistor R5. The anode of the second diode D2 is connected to the first terminal of the sixth resistor R7. The second terminal of the fifth resistor R5 is connected to the first terminal of the second resistor R2. The second terminal of the sixth resistor R7 is connected to the controllable power supply switch unit.

[0051] In the specific implementation process, the voltage of the first capacitor C1 is the voltage of the negative input terminal of comparator U2 (V-), and the reference voltage is the voltage of the positive input terminal of comparator U2 (Vref).

[0052] Comparator U2 compares the voltage of the first capacitor C1 with the reference voltage. When the voltage of the first capacitor C1 is greater than the reference voltage, comparator U2 outputs a low level; when the voltage of the first capacitor C1 is less than the reference voltage Vref, comparator U2 outputs a high level.

[0053] When comparator U2 outputs a low level, a voltage divider is used to clamp the voltage at the output of current sensing chip U1 to a lockout voltage, which is greater than the comparator's reference voltage. Specifically, when comparator U2 outputs a low level, the first resistor R1, the second resistor R2, the fifth resistor R5, and the first diode D1 form a voltage divider, so that the negative input terminal of current sensing chip U1 receives the voltage of the fifth resistor R5 and the first diode D1, and the voltage at the positive input terminal of current sensing chip U1 is equal to the voltage of the first resistor R1 and the second resistor R2. This makes the voltage at the negative input terminal of comparator U2 greater than the voltage at the positive input terminal of comparator U2. Until the overcurrent recovery time is reached, comparator U2 continues to output a low level, so that even after the power supply circuit disconnects the load after overcurrent protection, the output cannot be restored, thus achieving the overcurrent protection function.

[0054] When comparator U2 outputs a high level, the controllable power supply switch unit 103 is turned on, continuing to supply power to the load, and the power supply output is turned on.

[0055] In this embodiment, when the comparator U2 outputs a low level, the voltage at the output of the current detection chip U1 is clamped to a lockout voltage by a voltage divider element, so that the power supply circuit is always in an overcurrent protection state. Even if the load is disconnected, the power supply circuit cannot resume output, thereby improving the safety of the power supply circuit.

[0056] Please continue reading Figure 3 The controllable power supply switch unit includes a seventh resistor R6, an eighth resistor R8, a ninth resistor R9, a second transistor Q2, and a MOSFET Q1.

[0057] In this circuit, the source of MOSFET Q1 is connected to the second terminal of the first resistor R1, the first terminal of the seventh resistor R6, the emitter of the second transistor Q2, and the first terminal of the eighth resistor R8; the gate of MOSFET Q1 is connected to the collector of the second transistor Q2, the second terminal of the eighth resistor R8, and the first terminal of the ninth resistor R9; the drain of MOSFET Q1 is connected to the positive output terminal of the power supply circuit; the second terminal of the seventh resistor R6 is connected to the second terminal of the sixth resistor R7 and the base of the second transistor Q2; and the second terminal of the ninth resistor R9 is grounded.

[0058] In the specific implementation process, when the voltage at the negative input terminal of comparator U2 is greater than the voltage at the negative positive input terminal of comparator U2, comparator U2 outputs a low level. At this time, the second transistor Q2 is turned on, making the voltage across the eighth resistor R8 0, that is, the voltage difference between the gate and source of MOSFET Q1 is 0, and MOSFET Q1 is turned off, realizing the function of disconnecting the power supply output.

[0059] When the voltage at the negative input terminal of comparator U2 is less than the voltage at the positive input terminal of comparator U2, comparator U2 outputs a high level. At this time, the second transistor Q2 is not turned on, while the MOSFET Q1 is turned on normally, supplying power to the load. The second transistor Q2 is a PNP transistor, and the MOSFET Q1 is a P-MOS transistor.

[0060] In this embodiment, a high-side, low-power, single-signal controlled electronic switch is constructed using a transistor, a MOSFET, and three resistors. This switch is compatible with the preceding current detection, comparator, and voltage divider network, providing a simple, reliable, and extremely low-cost switch drive circuit for the entire circuit.

[0061] In some embodiments, MOSFET Q1 is a high-side switch.

[0062] This application embodiment, by setting a high-side switch, makes the power supply overcurrent protection circuit suitable for scenarios with high requirements for safety and anti-interference (such as automotive electronics).

[0063] Please continue reading Figure 3 The power supply overcurrent protection circuit also includes a second capacitor C2; the drain of the MOSFET Q1 is connected to the first terminal of the second capacitor C2, and the second terminal of the second capacitor C2 is grounded.

[0064] In this embodiment, a second capacitor C2 is connected between the drain of the MOSFET Q1 and ground for filtering, preventing noise from being transmitted to the load and improving the quality of the output signal.

[0065] In summary, the implementation principle of this application is as follows: The positive input terminal of the power supply overcurrent protection circuit is connected to ground with voltage, and the positive output terminal is connected to ground with the load.

[0066] The current flowing through the first resistor R1 and the second resistor R2 is converted into a voltage signal, which is then amplified proportionally by the current detection chip U1 and output from the output terminal of the current detection chip U1 to the third resistor R3. After flowing through the third resistor R3, the first capacitor C1 is charged.

[0067] Then, the voltage of the first capacitor C1 is output to the negative input terminal of comparator U2. If the voltage at the negative input terminal of comparator U2 is less than the voltage at the positive input terminal of comparator U2, comparator U2 outputs a high level, PNP transistor Q2 is turned on or off, and P-MOS transistor Q1 is turned on, which normally supplies power to the load.

[0068] If the voltage at the negative input terminal of comparator U2 is greater than the voltage at the positive input terminal of comparator U2, comparator U2 outputs a low level, PNP transistor Q2 is turned on, making the voltage across the eighth resistor R8 0, that is, the voltage difference between the gate and source of P-MOS transistor Q1 is 0, P-MOS transistor Q1 is turned off, realizing the function of disconnecting the power supply output.

[0069] After overcurrent protection occurs, an overcurrent recovery control command is generated through a timing program in the control port. Upon reaching the overcurrent recovery time, the control port outputs a high level, turning on the first transistor Q3. The first capacitor C1 discharges through the first transistor Q3, causing the voltage output to the comparator unit 102 to be less than the reference voltage, thus causing the comparator unit 102 to output a high level. After the comparator unit 102 outputs a high level, it controls the controllable power supply switch unit 103 to close, continuing to supply power to the load.

[0070] The timing program in the control port can be modified to adjust the overcurrent recovery time. The overcurrent protection value can be adjusted by adjusting the first resistor R1 or the reference voltage value.

[0071] In some embodiments, this application provides a power supply overcurrent protection device, which includes the power supply overcurrent protection circuit of any of the above embodiments.

[0072] In some embodiments, this application provides a vehicle that includes a power supply overcurrent protection circuit according to any of the above embodiments.

[0073] In the embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the displayed or discussed mutual couplings, direct couplings, or communication connections may be through some communication interfaces; indirect couplings or communication connections between devices or units may be electrical, mechanical, or other forms.

[0074] Furthermore, the units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0075] Furthermore, the functional modules in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0076] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A power supply overcurrent protection circuit, characterized in that, The power supply overcurrent protection circuit includes a current detection unit, a comparison unit, a controllable power supply switch unit, and an overcurrent recovery control unit; wherein, the overcurrent recovery control unit is configured to generate overcurrent recovery control commands; The current detection unit is used to detect the current signal of the power supply circuit, convert the current signal into a voltage signal, and output it to the comparison unit. The comparison unit is used to determine whether the power supply circuit is in an overcurrent state based on the voltage signal; and when it is determined that the power supply circuit is in the overcurrent state, it outputs a low level and controls the controllable power supply switch unit to open. The overcurrent recovery control unit is used to detect the output level of the comparison unit, and when the output level is low, it determines the overcurrent recovery time through the overcurrent recovery control command, and controls the comparison unit to output a high level when the overcurrent recovery time is reached, so as to control the controllable power supply switch unit to close through the comparison unit.

2. The power supply overcurrent protection circuit according to claim 1, characterized in that, in, The current detection unit includes a first resistor R1, a second resistor R2, a third resistor R3, a first capacitor C1, and a current detection chip U1; The positive input terminal of the current detection chip U1 is connected to the first terminal of the first resistor R1, and the negative input terminal of the current detection chip U1 is connected to the first terminal of the second resistor R2; the output terminal of the current detection chip U1 is connected to the first terminal of the third resistor R3. The second end of the first resistor R1 is connected to the second end of the second resistor R2; The first terminal of the first capacitor C1 is connected to the second terminal of the third resistor R3, and the second terminal of the first capacitor C1 is grounded.

3. The power supply overcurrent protection circuit according to claim 2, characterized in that, in, The overcurrent recovery control unit includes a first transistor Q3, a fourth resistor R4, and a control port; the control port is configured to generate the overcurrent recovery control command. The collector of the first transistor Q3 is connected to the first terminal of the first capacitor C1, the emitter of the first transistor Q3 is grounded, and the base of the first transistor Q3 is connected to the first terminal of the fourth resistor R4. The first end of the fourth resistor R4 is connected to the control port, and the second end of the fourth resistor R4 is grounded.

4. The power supply overcurrent protection circuit according to claim 2, characterized in that, in, The comparison unit includes a comparator U2 and a voltage divider element; The first end of the voltage divider element is connected to the negative input end of the current detection chip U1; The positive power supply terminal of the comparator U2 is connected to the positive input terminal of the power supply circuit, the negative power supply terminal of the comparator U2 is grounded, the negative input terminal of the comparator U2 is connected to the first terminal of the first capacitor C1, the positive input terminal of the comparator U2 is connected to the reference voltage, and the output terminal of the comparator U2 is connected to the second terminal of the voltage divider element. The voltage divider element is used to clamp the voltage at the output terminal of the current detection chip U1 to a lockout voltage when the comparator U2 outputs a low level, wherein the lockout voltage is greater than the reference voltage of the comparator.

5. The power supply overcurrent protection circuit according to claim 4, characterized in that, in, The voltage divider element includes a fifth resistor R5, a sixth resistor R7, a first diode D1, and a second diode D2; The output terminal of the comparator U2 is connected to the cathodes of the first diode D1 and the second diode D2, respectively. The anode of the first diode D1 is connected to the first terminal of the fifth resistor R5; the anode of the second diode D2 is connected to the first terminal of the sixth resistor R7. The second end of the fifth resistor R5 is connected to the first end of the second resistor R2; The second end of the sixth resistor R7 is connected to the controllable power supply switch unit.

6. The power supply overcurrent protection circuit according to claim 5, characterized in that, in, The controllable power supply switch unit includes a seventh resistor R6, an eighth resistor R8, a ninth resistor R9, a second transistor Q2, and a MOSFET Q1; The source of the MOSFET Q1 is connected to the second terminal of the first resistor R1, the first terminal of the seventh resistor R6, the emitter of the second transistor Q2, and the first terminal of the eighth resistor R8, respectively; the gate of the MOSFET Q1 is connected to the collector of the second transistor Q2, the second terminal of the eighth resistor R8, and the first terminal of the ninth resistor R9, respectively; the drain of the MOSFET Q1 is connected to the positive output terminal of the power supply circuit. The second terminal of the seventh resistor R6 is connected to the second terminal of the sixth resistor R7 and the base of the second transistor Q2, respectively. The second terminal of the ninth resistor R9 is grounded.

7. The power supply overcurrent protection circuit according to claim 6, characterized in that, in, The MOSFET Q1 is a high-side switch.

8. The power supply overcurrent protection circuit according to any one of claims 6-7, characterized in that, in, The power supply overcurrent protection circuit also includes a second capacitor C2; The drain of the MOS transistor Q1 is connected to the first terminal of the second capacitor C2, and the second terminal of the second capacitor C2 is grounded.

9. A power supply overcurrent protection device, characterized in that, The device includes the power supply overcurrent protection circuit as described in any one of claims 1-8.

10. A vehicle, characterized in that, The vehicle includes the power supply overcurrent protection circuit as described in any one of claims 1-8.

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