Overvoltage protection circuit, overvoltage protection device and electronic equipment

Abstract

The present application discloses an overvoltage protection circuit, an overvoltage protection device, and an electronic device. The voltage detection circuit detects the input voltage, and generates a first control signal according to the voltage difference between the input voltage and the first clamping voltage when the input voltage is greater than the preset voltage; the response circuit outputs a second control signal according to the input voltage when the first control signal is input; the switch circuit stops transferring the input voltage to the electrical device when the second control signal is input; thus, when the input voltage is greater than the preset voltage, the input voltage is stopped from being output to the electrical device, thereby protecting the electrical device. At the same time, there is no need to use a comparator for signal conversion, and the input voltage can be quickly stopped from being transferred to the electrical device according to the changed input voltage, which shortens the action time of the overvoltage protection and improves the timeliness of the overvoltage protection.

Description

Technical Field

[0001] The present application belongs to the technical field of overvoltage protection, and in particular, relates to an overvoltage protection circuit, an overvoltage protection device, and an electronic device. Background Art

[0002] Traditional overvoltage protection circuits generally detect the power supply voltage value through a resistor voltage detection circuit and a comparison circuit. When the power supply voltage value is greater than the preset voltage, the comparison circuit drives the field effect tube to cut off the field effect tube, thereby stopping the output voltage to the electrical equipment, thereby protecting the electrical equipment. However, the time constant and bandwidth limitations of the power supply voltage value detection module composed of the voltage detection circuit and the comparison circuit cause the response time of the power supply voltage value detection module to be too long. Therefore, when the power supply generates a spike voltage, the power supply voltage to the detection module cannot respond in time, and the field effect tube will output the spike voltage to the electrical equipment, causing the electrical equipment to be damaged under the action of the spike voltage. Summary of the invention

[0003] The purpose of the present application is to provide an overvoltage protection circuit, aiming to solve the problem that the response time of the traditional overvoltage protection circuit is too long, resulting in poor overvoltage protection effect.

[0004] A first aspect of an embodiment of the present application provides an overvoltage protection circuit, comprising:

[0005] a voltage detection circuit configured to detect an input voltage, and when the input voltage is greater than a preset voltage, generate a first control signal according to a voltage difference between the input voltage and a first clamping voltage;

[0006] a response circuit connected to the voltage detection circuit and configured to output a second control signal according to the input voltage when the first control signal is input; and

[0007] The switch circuit is connected to the response circuit and is configured to stop transferring the input voltage to the electrical device when the second control signal is input.

[0008] In one embodiment, the voltage detection circuit includes a bias component and a detection component;

[0009] The bias component is configured to output a bias voltage according to the input voltage;

[0010] The detection component is connected to the bias component and is configured to generate the first control signal according to a voltage difference between the input voltage and the first clamping voltage when the bias voltage is input and when the input voltage is greater than the preset voltage.

[0011] In one embodiment, the bias component includes a first Zener diode and a first resistor;

[0012] The cathode of the first Zener diode is connected to the input voltage input terminal of the bias component, the anode of the first Zener diode is connected to the first end of the first resistor and to the bias voltage output terminal of the bias component, and the second end of the first resistor is connected to the power ground.

[0013] In one embodiment, the detection component includes a first field effect transistor, a second resistor and a first diode;

[0014] The first end of the second resistor is connected to the input voltage input terminal of the detection component, the gate of the first field effect transistor is connected to the bias voltage input terminal of the detection component, the source of the first field effect transistor is connected to the second end of the second resistor and to the first control signal output terminal of the detection component, the drain of the first field effect transistor is connected to the anode of the first diode, and the cathode of the first diode is connected to the first clamping voltage input terminal of the detection component.

[0015] In one embodiment, the response circuit includes a second field effect transistor, a second Zener diode and a third resistor;

[0016] The gate of the second field effect transistor is connected to the first control signal input terminal of the response circuit, the source of the second field effect transistor is connected to the cathode of the second Zener diode and is connected to the input voltage input terminal of the response circuit, the drain of the second field effect transistor, the first end of the third resistor and the anode of the second Zener diode are connected in common and connected to the second control signal output terminal of the response circuit, and the second end of the third resistor is connected to the power ground.

[0017] In one embodiment, the switch circuit includes a third field effect transistor;

[0018] The gate of the third field effect transistor is connected to the second control signal input terminal of the switch circuit, the source of the third field effect transistor is connected to the input voltage input terminal of the switch circuit, and the drain of the third field effect transistor is connected to the input voltage output terminal of the switch circuit.

[0019] In one embodiment, the overvoltage protection circuit further includes a current detection circuit and a logic control circuit;

[0020] The current detection circuit is configured to detect the operating current of the electrical device and output a third control signal when the operating current is greater than a preset current;

[0021] The logic control circuit is connected to the current detection circuit, the voltage detection circuit and the response circuit respectively, and is configured to output a pull-down voltage and a second clamping voltage when the third control signal is input;

[0022] The voltage detection circuit is further configured to output the first control signal when the pull-down voltage is input;

[0023] The response circuit is further configured to reduce the freewheeling current generated by the input voltage to zero when the second clamping voltage is input.

[0024] In one embodiment, the logic control circuit includes a fourth field effect transistor, an inverter, a fifth field effect transistor and a second diode;

[0025] The gate of the fourth field effect transistor is connected to the output end of the inverter, the drain of the fourth field effect transistor is connected to the pull-down voltage output end of the logic control circuit, the source of the fourth field effect transistor and the source of the fifth field effect transistor are both connected to the power ground, the input end of the inverter and the gate of the fifth field effect transistor are both connected to the third control signal input end of the logic control circuit, the drain of the fifth field effect transistor is connected to the anode of the second diode and to the second clamping voltage output end of the logic control circuit, and the cathode of the second diode is used to connect to a reference voltage source.

[0026] A second aspect of an embodiment of the present application provides an overvoltage protection device, comprising an overvoltage protection circuit as described in any one of the first aspects.

[0027] A third aspect of an embodiment of the present application provides an electronic device, comprising an overvoltage protection device as described in any one of the first aspects.

[0028] Compared with the prior art, the embodiments of the present invention have the following beneficial effects: the input voltage is detected by the voltage detection circuit, and when the input voltage is greater than the preset voltage, a first control signal is generated according to the voltage difference between the input voltage and the first clamping voltage; when the first control signal is input, the response circuit outputs a second control signal according to the input voltage; when the second control signal is input, the switch circuit stops transferring the input voltage to the electrical device; thus, when the input voltage is greater than the preset voltage, the input voltage is stopped from being output to the electrical device, thereby protecting the electrical device. At the same time, there is no need to use a comparator for signal conversion, and the input voltage can be quickly stopped from being transferred to the electrical device according to the changed input voltage, which shortens the action time of the overvoltage protection and improves the timeliness of the overvoltage protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A first exemplary principle block diagram of an overvoltage protection circuit provided in an embodiment of the present application;

[0030] Figure 2 A second exemplary principle block diagram of an overvoltage protection circuit provided in an embodiment of the present application;

[0031] Figure 3A first exemplary circuit schematic diagram of an overvoltage protection circuit provided in an embodiment of the present application;

[0032] Figure 4 A third exemplary principle block diagram of an overvoltage protection circuit provided in an embodiment of the present application;

[0033] Figure 5 A second exemplary circuit schematic diagram of the overvoltage protection circuit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0034] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0035] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0036] See also Figure 1 An embodiment of the present application provides an overvoltage protection circuit, which includes a voltage detection circuit 100, a response circuit 200 and a switch circuit 300.

[0037] The voltage detection circuit 100 is configured to detect an input voltage, and when it is detected that the input voltage is greater than a preset voltage, generate a first control signal according to a voltage difference between the input voltage and a first clamping voltage.

[0038] The response circuit 200 is connected to the voltage detection circuit 100 and is configured to output a second control signal according to the input voltage when the first control signal is input.

[0039] The switch circuit 300 is connected to the response circuit 200 and is configured to stop transferring the input voltage to the power-consuming device 400 when the second control signal is input.

[0040] In this embodiment, the voltage detection circuit 100 detects the input voltage output by the power supply 500, and when the input voltage is greater than the preset voltage, the voltage difference between the input voltage and the first clamping voltage is output as the first control signal to the response circuit 200. When the response circuit 200 receives the first control signal, it outputs the second control signal to the switch circuit 300 according to the input voltage. When the switch circuit 300 receives the second control signal, it stops transferring the input voltage to the power-consuming device 400. When the input voltage output by the power supply 500 is greater than the preset voltage, the switch circuit 300 will not output the input voltage to the power-consuming device 400, so the power-consuming device 400 will not be damaged due to the application of the abnormally increased input voltage. At the same time, because the voltage detection circuit 100 generates the first control signal based on the voltage difference between the input voltage and the first clamping voltage, the essence of the first control signal is a part of the input voltage. In other words, the first control signal can be obtained directly through the input voltage. Therefore, the first control signal does not need to be converted by a comparator, and there will be no problem of poor overvoltage protection due to the long response time when using a comparator. Therefore, when the input voltage suddenly rises (greater than the preset voltage), the voltage detection circuit 100 can quickly output the first control signal according to the changed input voltage to stop the switch circuit 300 from transferring the input voltage to the electrical device 400, thereby shortening the action time of the overvoltage protection and improving the timeliness of the overvoltage protection.

[0041] The preset voltage is greater than the rated voltage of the electric device 400, and is a preset voltage that the electric device 400 is to avoid. The voltage that the electric device 400 is to avoid is a voltage that may damage the electric device 400, or a voltage that is artificially set and is not allowed to be applied to the electric device 400. The specific value of the preset voltage is set by those skilled in the art according to the actual needs of the electric device 400.

[0042] Wherein, without considering the on-state voltage drop of the internal components of the response circuit 200, the first control signal is equal to the voltage difference between the input voltage and the first clamping voltage. Under the premise of considering the voltage drop of the internal components of the response circuit 200, the first control signal is equal to the difference between the input voltage minus the first clamping voltage and the on-state voltage drop of the internal components of the response circuit 200; for example, when the response circuit 200 includes a diode, the first control signal is equal to the difference between the input voltage minus the first clamping voltage and the on-state threshold voltage of the diode.

[0043] See also Figure 2 In one embodiment, the voltage detection circuit 100 includes a bias component 110 and a detection component 120 .

[0044] The bias component 110 is configured to output a bias voltage according to an input voltage.

[0045] The detection component 120 is connected to the bias component 110 and is configured to generate a first control signal according to a voltage difference between the input voltage and the first clamping voltage when a bias voltage is input and when the input voltage is greater than a preset voltage.

[0046] In this embodiment, when the bias component 110 detects an input voltage, the bias component 110 outputs the bias voltage to the detection component 120. The detection component 120 works when the bias voltage is input, and when the input voltage is greater than the preset voltage, the voltage difference between the input voltage and the first clamping voltage is output as the first control signal. When the input voltage is detected, the bias component 110 outputs the bias voltage to the detection component 120 to make the detection component 120 work to detect the input voltage, and then when the input voltage is greater than the preset voltage, the detection component 120 can react quickly and output the first control signal.

[0047] In this embodiment, in one implementation, the bias component 110 is configured to output a bias voltage when the input voltage is greater than the rated voltage of the power-consuming device 400. When the input voltage is equal to the rated voltage of the power-consuming device 400, the bias component 110 outputs the bias voltage to the detection component 120, so that the detection component 120 can work only after the power-consuming device 400 works normally, thereby reducing the unnecessary use time of the detection component 120. The normal operation of the power-consuming device 400 means that the input voltage applied to the power-consuming device 400 is equal to the rated voltage.

[0048] See also Figure 3 In one embodiment, the biasing element 110 includes a first Zener diode Z1 and a first resistor R1.

[0049] The cathode of the first Zener diode Z1 is connected to the input voltage VIN input terminal of the bias component 110, the anode of the first Zener diode Z1 is connected to the first end of the first resistor R1 and to the bias voltage output terminal of the bias component 110, and the second end of the first resistor R1 is connected to the power ground.

[0050] See also Figure 3 In one embodiment, the detection component 120 includes a first field effect transistor Q1, a second resistor R2 and a first diode D1.

[0051] The first end of the second resistor R2 is connected to the input voltage VIN input terminal of the detection component 120, the gate of the first field effect transistor Q1 is connected to the bias voltage input terminal of the detection component 120, the source of the first field effect transistor Q1 is connected to the second end of the second resistor R2 and to the first control signal output terminal of the detection component 120, the drain of the first field effect transistor Q1 is connected to the anode of the first diode D1, and the cathode of the first diode D1 is connected to the first clamping voltage input terminal of the detection component.

[0052] The first clamping voltage is provided by a reference voltage source, and the first clamping voltage is equal to the reference voltage.

[0053] See also Figure 3 In one embodiment, the response circuit 200 includes a second field effect transistor Q2, a second Zener diode Z2 and a third resistor R3.

[0054] The gate of the second field effect transistor Q2 is connected to the first control signal input terminal of the response circuit 200, the source of the second field effect transistor Q2 is connected to the cathode of the second Zener diode Z2 and connected to the input voltage VIN input terminal of the response circuit 200, the drain of the second field effect transistor Q2, the first end of the third resistor R3 and the anode of the second Zener diode Z2 are connected in common and connected to the second control signal output terminal of the response circuit 200, and the second end of the third resistor R3 is connected to the power ground.

[0055] See also Figure 3 In one embodiment, the switch circuit 300 includes a third field effect transistor Q3.

[0056] The gate of the third field effect transistor Q3 is connected to the second control signal input terminal of the switch circuit 300, the source of the third field effect transistor Q3 is connected to the input voltage VIN input terminal of the switch circuit 300, and the drain of the third field effect transistor Q3 is connected to the input voltage VIN output terminal of the switch circuit 300.

[0057] The following is combined with the working principle Figure 3 The overvoltage protection circuit shown is explained:

[0058] When the input voltage VIN is normal, that is, when the input voltage VIN is the rated voltage of the electrical device 400, the first Zener diode Z1 is turned on, the gate voltage of the first field effect transistor Q1 reaches the turn-on voltage, and the first field effect transistor Q1 is turned on. The input voltage VIN acts on the source of the first field effect transistor Q1 through the second resistor R2. At this time, the first clamping voltage VDD clamps the drain of the first field effect transistor Q1 through the first diode D1. The voltage of the drain of the first field effect transistor Q1 is the sum of the reference voltage VDD and the threshold voltage of the first diode D1. Because the source voltage of the first field effect transistor Q1 is not greater than the drain voltage of the first field effect transistor Q1, no current flows through the first field effect transistor Q1. The voltage of the gate of the second field effect transistor Q2 is equal to the input voltage VIN, which is a high level, so the second field effect transistor Q2 is turned off. When the second FET Q2 is turned off and the second Zener diode Z2 is turned on, the gate voltage of the third FET Q3 reaches the turn-on voltage, the third FET Q3 is turned on and transfers the input voltage VIN to the electrical device 400, so that the electrical device 400 works.

[0059] When the power supply is unstable or the voltage is abnormal during the power supply process, the input voltage VIN will continue to increase from the rated voltage of the power-consuming device 400. At this time, the input voltage VIN is greater than the sum of the first clamping voltage VDD and the threshold voltage of the first diode D1, and the current starts to flow through the branch where the first field effect transistor Q1 and the second resistor R2 are located. When the input voltage VIN continues to increase and increases to a voltage greater than the preset voltage, the voltage difference across the second resistor R2 is equal to the difference between the input voltage minus the first clamping voltage VDD and the threshold voltage of the first diode D1. At this time, the voltage difference across the second resistor R2 acts on the gate and source of the second field effect transistor Q2 and turns on the second field effect transistor Q2 (equivalent to the second end of the second resistor R2 outputting a low-level first control signal to the gate of the second field effect transistor Q2 to turn on the second field effect transistor Q2). The input voltage VIN acts on the gate of the third field effect transistor Q3 through the second field effect transistor Q2, and the third field effect transistor Q3 is turned off, so the third field effect transistor Q3 stops transferring the input voltage VIN to the power-consuming device 400.

[0060] When the input voltage VIN returns to normal voltage, because the input voltage VIN is less than the preset voltage, the current of the branch where the second resistor R2 and the first field effect transistor Q1 are located is 0. At this time, the input voltage VIN directly acts on the second field effect transistor Q2 through the second resistor R2 to cut off the second field effect transistor Q2. The third field effect transistor Q3 is turned on by the second Zener diode Z2, and the input voltage VIN is re-transferred to the electrical device 400, so that the electrical device 400 resumes working.

[0061] The overvoltage protection circuit of this embodiment does not use a comparator to compare the input voltage VIN with the preset voltage. Therefore, there is no problem of poor overvoltage protection effect caused by the long response time when using a comparator. Therefore, when the input voltage VIN suddenly increases and exceeds the preset voltage, it can quickly stop transferring the input voltage VIN to the electrical equipment 400, thereby shortening the action time of the overvoltage protection and improving the timeliness of the overvoltage protection.

[0062] See also Figure 4 In one embodiment, the overvoltage protection circuit further includes a current detection circuit 600 and a logic control circuit 700 .

[0063] The current detection circuit 600 is configured to detect the operating current of the electrical device 400, and output a third control signal when the operating current is greater than a preset current.

[0064] The logic control circuit 700 is connected to the current detection circuit 600 , the voltage detection circuit 100 and the response circuit 200 , respectively, and is configured to output a pull-down voltage and a second clamping voltage when a third control signal is input.

[0065] The voltage detection circuit 100 is further configured to output a first control signal when a pull-down voltage is input.

[0066] The response circuit 200 is further configured to reduce the freewheeling current generated by the input voltage to zero when the second clamping voltage is input.

[0067] In this embodiment, the current detection circuit 600 detects the operating current of the electric device 400, and outputs a third control signal to the logic control circuit 700 when the operating current is greater than the preset current. The logic control circuit 700 outputs a pull-down voltage to the voltage detection circuit 100 when the third control signal is input, and outputs a second clamping voltage to the response circuit 200. The voltage detection circuit 100 outputs a first control signal when the pull-down voltage is input, so that the response circuit 200 outputs a second control signal to the switch circuit 300 according to the input voltage, and then the switch circuit 300 stops transferring the input voltage to the electric device 400. By cutting off the power supply to the electric device 400 when an overcurrent occurs in the electric device 400, the electric device 400 is protected. In addition, the response circuit will work according to the input voltage when the first control signal is input, and the inside of the response circuit will generate a freewheeling current due to the work during operation; therefore, the response circuit 200 of this embodiment also offsets the input voltage through the second clamping voltage, so that the voltage difference generated by the input voltage acting on the response circuit 200 is 0, so that the freewheeling current of the response circuit 200 is reduced to 0, thereby reducing the energy consumption of the response circuit 200. When the electrical device 400 has an overcurrent, the temperature of the electrical device 400 will rise, and the temperature rise of the electrical device 400 will cause the electrical device 400 to continue to maintain the overcurrent phenomenon, which will cause the overcurrent time of the electrical device 400 to be relatively long. In other words, the freewheeling current of the response circuit 200 will exist for a relatively long time, so by reducing the freewheeling current to 0, a lot of energy consumption can be saved, effectively improving economic benefits.

[0068] See also Figure 5 In one embodiment, the logic control circuit 700 includes a fourth field effect transistor Q4, an inverter U1, a fifth field effect transistor Q5 and a second diode D2.

[0069] The gate of the fourth field effect transistor Q4 is connected to the output end of the inverter U1, the drain of the fourth field effect transistor Q4 is connected to the pull-down voltage output end of the logic control circuit 700, the source of the fourth field effect transistor Q4 and the source of the fifth field effect transistor Q5 are both connected to the power ground, the input end of the inverter U1 and the gate of the fifth field effect transistor Q5 are both connected to the third control signal input end of the logic control circuit 700, the drain of the fifth field effect transistor Q5 is connected to the anode of the second diode D2 and to the second clamping voltage output end of the logic control circuit 700, and the cathode of the second diode D2 is used to connect to the reference voltage source.

[0070] The reference voltage source may be provided by an external power source, which may be a battery, etc. The voltage of the reference voltage source is designed by those skilled in the art according to the description of this embodiment and actual needs.

[0071] In this embodiment, when the current detection module detects that the working current of the electric device 400 is greater than the preset current, the current detection module outputs a low level to the input end of the inverter U1 and the gate of the fifth field effect transistor Q5, and the fifth field effect transistor Q5 is turned off. The inverter U1 outputs a high level to the gate of the fourth field effect transistor Q4, and the fourth field effect transistor Q4 is turned on. The drain of the first field effect transistor Q1 is connected to the power ground through the fourth field effect transistor Q4, so when the input voltage VIN is a normal voltage, the first field effect transistor Q1 is turned on, the gate of the second field effect transistor Q2 is connected to the power ground through the first field effect transistor Q1 and the fourth field effect transistor Q4, the gate voltage of the second field effect transistor Q2 is pulled down to the ground potential, and the second field effect transistor Q2 is turned on. The input voltage VIN acts on the gate of the third field effect transistor Q3 through the second field effect transistor Q2, so that the third field effect transistor Q3 is turned off and stops transferring the input voltage VIN to the electric device 400. The fifth field effect transistor Q5 is turned off, so that the freewheeling current of the branch where the third resistor R3 is located is reduced to 0. The second diode D2 outputs a second clamping voltage under the action of the reference voltage VDD, and acts on the drain of the fifth field effect transistor Q5 and the gate of the third field effect transistor Q3 to protect the drain of the fifth field effect transistor Q5 and the gate of the third field effect transistor Q3 from being damaged by the high voltage impact of the power supply.

[0072] An embodiment of the present application also provides an overvoltage protection device, including the overvoltage protection circuit of any of the above embodiments. Therefore, the overvoltage protection device of this embodiment includes the overvoltage protection circuit of any of the above embodiments. Therefore, the overvoltage protection device of this embodiment at least includes the beneficial effects corresponding to the overvoltage protection circuit of any of the above embodiments.

[0073] An embodiment of the present application also provides an electronic device, including the overvoltage protection circuit of any of the above embodiments. Therefore, the electronic device of this embodiment includes the overvoltage protection circuit of any of the above embodiments. Therefore, the electronic device of this embodiment at least includes the beneficial effects corresponding to the overvoltage protection circuit of any of the above embodiments.

[0074] In some of the embodiments, the electronic device may be a power supply device, a Bluetooth headset, or other device that requires overvoltage protection.

[0075] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. An overvoltage protection circuit, characterized in that: include: a voltage detection circuit configured to detect an input voltage, and when the input voltage is greater than a preset voltage, generate a first control signal according to a voltage difference between the input voltage and a first clamping voltage; a response circuit connected to the voltage detection circuit and configured to output a second control signal according to the input voltage when the first control signal is input; as well as a switch circuit connected to the response circuit and configured to stop transferring the input voltage to the power-consuming device when the second control signal is input; The overvoltage protection circuit also includes a current detection circuit and a logic control circuit; The current detection circuit is configured to detect the operating current of the electrical device and output a third control signal when the operating current is greater than a preset current; The logic control circuit is connected to the current detection circuit, the voltage detection circuit and the response circuit respectively, and is configured to output a pull-down voltage and a second clamping voltage when the third control signal is input; The voltage detection circuit is further configured to output the first control signal when the pull-down voltage is input; The response circuit is further configured to reduce the freewheeling current generated by the input voltage to zero when the second clamping voltage is input.

2. The overvoltage protection circuit according to claim 1, characterized in that: The voltage detection circuit includes a bias component and a detection component; The bias component is configured to output a bias voltage according to the input voltage; The detection component is connected to the bias component and is configured to generate the first control signal according to a voltage difference between the input voltage and the first clamping voltage when the bias voltage is input and when the input voltage is greater than the preset voltage.

3. The overvoltage protection circuit according to claim 2, characterized in that: The biasing component includes a first Zener diode and a first resistor; The cathode of the first Zener diode is connected to the input voltage input terminal of the bias component, the anode of the first Zener diode is connected to the first end of the first resistor and to the bias voltage output terminal of the bias component, and the second end of the first resistor is connected to the power ground.

4. The overvoltage protection circuit according to claim 2, characterized in that: The detection component includes a first field effect transistor, a second resistor and a first diode; The first end of the second resistor is connected to the input voltage input terminal of the detection component, the gate of the first field effect transistor is connected to the bias voltage input terminal of the detection component, the source of the first field effect transistor is connected to the second end of the second resistor and to the first control signal output terminal of the detection component, the drain of the first field effect transistor is connected to the anode of the first diode, and the cathode of the first diode is connected to the first clamping voltage input terminal of the detection component.

5. The overvoltage protection circuit according to claim 1, characterized in that: The response circuit includes a second field effect transistor, a second Zener diode and a third resistor; The gate of the second field effect transistor is connected to the first control signal input terminal of the response circuit, the source of the second field effect transistor is connected to the cathode of the second Zener diode and is connected to the input voltage input terminal of the response circuit, the drain of the second field effect transistor, the first end of the third resistor and the anode of the second Zener diode are connected in common and connected to the second control signal output terminal of the response circuit, and the second end of the third resistor is connected to the power ground.

6. The overvoltage protection circuit according to claim 1, characterized in that: The switch circuit includes a third field effect transistor; The gate of the third field effect transistor is connected to the second control signal input terminal of the switch circuit, the source of the third field effect transistor is connected to the input voltage input terminal of the switch circuit, and the drain of the third field effect transistor is connected to the input voltage output terminal of the switch circuit.

7. The overvoltage protection circuit according to claim 1, characterized in that: The logic control circuit includes a fourth field effect transistor, an inverter, a fifth field effect transistor and a second diode; The gate of the fourth field effect transistor is connected to the output end of the inverter, the drain of the fourth field effect transistor is connected to the pull-down voltage output end of the logic control circuit, the source of the fourth field effect transistor and the source of the fifth field effect transistor are both connected to the power ground, the input end of the inverter and the gate of the fifth field effect transistor are both connected to the third control signal input end of the logic control circuit, the drain of the fifth field effect transistor is connected to the anode of the second diode and to the second clamping voltage output end of the logic control circuit, and the cathode of the second diode is used to connect to a reference voltage source.

8. An overvoltage protection device, characterized in that: The invention comprises an overvoltage protection circuit as claimed in any one of claims 1 to 7.

9. An electronic device, characterized in that: The invention comprises an overvoltage protection circuit as claimed in any one of claims 1 to 7.

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