Over-voltage and under-voltage detection circuit and electronic equipment

Abstract

The utility model provides an overvoltage and undervoltage detection circuit and electronic equipment, the overvoltage and undervoltage detection circuit comprises at least one group of overvoltage and undervoltage detection units, and each overvoltage and undervoltage detection unit comprises a first voltage division circuit with an input end connected with a first power supply, an output end connected with an inverted input end of the overvoltage detection circuit, and a second voltage division circuit with an output end connected with an inverted input end of the overvoltage detection circuit; the positive phase input end of the overvoltage detection circuit is connected with a to-be-detected voltage; the input end of the second voltage division circuit is connected with the first power supply, the output end of the second voltage division circuit is connected with the normal phase input end of the under-voltage detection circuit, and the normal phase input end of the under-voltage detection circuit is connected with voltage to be detected; wherein the first voltage division circuit is used for performing voltage division on a first input power supply and outputting a first reference voltage, the second voltage division circuit is used for performing voltage division on the first input power supply and outputting a second reference voltage, and the first reference voltage is greater than the second reference voltage. Each overvoltage and undervoltage detection unit is independent, can be expanded according to needs, and has good expandability.

Description

Technical Field

[0001] This utility model relates to the field of circuit technology, specifically to an over / under voltage detection circuit and electronic device. Background Technology

[0002] In the fields of power electronics and power management, voltage stability is crucial for the normal operation and performance of equipment. To enhance equipment protection, more and more devices require voltage monitoring.

[0003] In existing voltage detection circuits, it is common practice to add peripheral circuits to the main control chip and add algorithms to the main control chip to determine the voltage. This increases the complexity of the peripheral circuits and consumes the computing resources of the main control chip. Furthermore, the limited number of ports on the main control chip results in poor circuit scalability. Utility Model Content

[0004] The main purpose of this utility model is to provide an over / under voltage detection circuit and electronic device, which realizes over / under voltage detection through the circuit and has good scalability.

[0005] To solve the above-mentioned technical problems, the first technical solution provided in this application is: to provide an over / under voltage detection circuit, including at least one set of over / under voltage detection units, each over / under voltage detection unit including: a first input power supply, a first voltage divider circuit, a second voltage divider circuit, an overvoltage detection circuit, and an undervoltage detection circuit; the input terminal of the first voltage divider circuit is connected to the first power supply, the output terminal of the first voltage divider circuit is connected to the inverting input terminal of the overvoltage detection circuit, and the non-inverting input terminal of the overvoltage detection circuit is connected to the voltage to be measured; the input terminal of the second voltage divider circuit is connected to the first power supply, the output terminal of the second voltage divider circuit is connected to the non-inverting input terminal of the undervoltage detection circuit, and the non-inverting input terminal of the undervoltage detection circuit is connected to the voltage to be measured; wherein, the first voltage divider circuit is used to divide the first input power supply to output a first reference voltage, the second voltage divider circuit is used to divide the first input power supply to output a second reference voltage, and the first reference voltage is greater than the second reference voltage.

[0006] Preferably, the over / under voltage detection unit further includes a protection circuit, the input terminal of which is connected to the detection voltage, and the voltage output by the output terminal of the protection circuit is used as the voltage to be measured.

[0007] Preferably, the protection circuit includes a first resistor unit, a second resistor, and a first capacitor. One end of the first resistor unit is connected to the detection voltage, the other end of the first resistor unit is connected to one end of the second resistor, the other end of the second resistor is grounded, the first capacitor is connected in parallel with the second resistor, and the other end of the first resistor unit serves as the output terminal of the protection circuit for outputting the voltage to be measured.

[0008] Preferably, the first resistor unit includes a first resistor and a second resistor. One end of the first resistor is connected to the detection voltage, and the other end of the first resistor is connected to one end of the second resistor. The other end of the second resistor is connected to the output terminal of the protection circuit for outputting the voltage to be measured.

[0009] Preferably, the first voltage divider circuit includes a first voltage divider resistor, a second voltage divider resistor, and a second capacitor. One end of the first voltage divider resistor is connected to a first power supply, and the other end of the first voltage divider resistor is connected to the inverting input of an overvoltage detection circuit as the output of the first voltage divider circuit. One end of the second voltage divider resistor is connected to the other end of the first voltage divider resistor, and the other end of the second voltage divider resistor is grounded. The second capacitor is connected in parallel with the second voltage divider resistor. The second voltage divider circuit includes a third voltage divider resistor, a fourth voltage divider resistor, and a third capacitor. One end of the third voltage divider resistor is connected to the first power supply, and the other end of the third voltage divider resistor is connected to the non-inverting input of an undervoltage detection circuit as the output of the second voltage divider circuit. One end of the fourth voltage divider resistor is connected to the other end of the third voltage divider resistor, and the other end of the fourth voltage divider resistor is grounded. The third capacitor is connected in parallel with the fourth voltage divider resistor.

[0010] Preferably, the first voltage divider circuit includes a first adjustable resistor, a second adjustable resistor, and a second capacitor; one end of the first adjustable resistor is connected to a first power supply, and the other end of the first adjustable resistor serves as the output terminal of the first voltage divider circuit and is connected to the inverting input terminal of the overvoltage detection circuit; one end of the second adjustable resistor is connected to the other end of the first adjustable resistor, and the other end of the second adjustable resistor is grounded; the second capacitor is connected in parallel with the second adjustable resistor; the second voltage divider circuit includes a third adjustable resistor, a fourth adjustable resistor, and a third capacitor; one end of the third adjustable resistor is connected to the first power supply, and the other end of the third adjustable resistor serves as the output terminal of the second voltage divider circuit and is connected to the non-inverting input terminal of the undervoltage detection circuit; one end of the fourth adjustable resistor is connected to the other end of the third adjustable resistor, and the other end of the fourth adjustable resistor is grounded; the third capacitor is connected in parallel with the fourth adjustable resistor.

[0011] Preferably, the overvoltage detection circuit includes a first operational amplifier, the inverting input terminal of the first operational amplifier is connected to the output terminal of the first voltage divider circuit through a resistor, the non-inverting input terminal of the first operational amplifier is connected to the output terminal of the protection circuit through a resistor, the power supply terminal of the first operational amplifier is connected to a second power supply, and the output terminal of the first operational amplifier is used to output an overvoltage signal.

[0012] Preferably, the undervoltage detection circuit includes a second operational amplifier. The inverting input terminal of the second operational amplifier is connected to the output terminal of the protection circuit through a resistor, and the non-inverting input terminal of the second operational amplifier is connected to the output terminal of the second voltage divider circuit through a resistor. The output terminal of the second operational amplifier is used to output an undervoltage signal.

[0013] Preferably, the overvoltage detection circuit further includes a fourth capacitor, one end of which is connected to the power supply terminal of the first operational amplifier, and the other end of which is grounded.

[0014] To solve the above-mentioned technical problems, this application also provides an electronic device, including the above-mentioned over / under voltage detection circuit.

[0015] The beneficial effects of this application, unlike existing technologies, are that the over / under voltage detection circuit includes at least one set of over / under voltage detection units. Each over / under voltage detection unit receives power from a first input power supply, divides the first input power supply using a first voltage divider circuit to output a first reference voltage, and divides the first input power supply using a second voltage divider circuit to output a second reference voltage lower than the first reference voltage. The overvoltage detection circuit compares the voltage to be measured with the first reference voltage to determine if an overvoltage condition exists, and the undervoltage detection circuit compares the voltage to be measured with the second reference voltage to determine if an undervoltage condition exists. Each over / under voltage detection unit is independent and can be expanded as needed to add more detection units to monitor more voltage points, exhibiting good scalability. Attached Figure Description

[0016] The present application will be further described below with reference to the accompanying drawings and embodiments. In the drawings:

[0017] Figure 1 This is a schematic diagram of the framework of an embodiment of the over / under voltage detection circuit provided in this application;

[0018] Figure 2 This is a circuit diagram of a protection circuit according to an embodiment of the over / under voltage detection circuit provided in this application;

[0019] Figure 3 This is a circuit diagram of the first voltage divider circuit and the overvoltage detection circuit of an embodiment of the overvoltage and undervoltage detection circuit provided in this application;

[0020] Figure 4 This is a circuit diagram of the second voltage divider circuit and the undervoltage detection circuit of an embodiment of the overvoltage and undervoltage detection circuit provided in this application;

[0021] Figure 5 This is a circuit diagram of the first voltage divider circuit and the overvoltage detection circuit of another embodiment of the overvoltage and undervoltage detection circuit provided in this application;

[0022] Figure 6 This is a circuit diagram of the second voltage divider circuit and the undervoltage detection circuit of another embodiment of the overvoltage and undervoltage detection circuit provided in this application;

[0023] Figure 7 This is a schematic diagram of the framework of an embodiment of the electronic device provided in this application. Detailed Implementation

[0024] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It is understood that the specific embodiments described herein are only for explaining this application and not for limiting it. It should also be noted that, for ease of description, only the parts related to this application are shown in the drawings, not all structures. All other embodiments obtained by those skilled in the art based on the embodiments in this application without creative effort are within the scope of protection of this application. The basic principles, main features, and advantages of this utility model have been shown and described above. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are only illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of protection of this utility model as claimed. The scope of protection of this utility model is defined by the appended claims and their equivalents.

[0025] The terms “first,” “second,” and “third” used in this application are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as “first,” “second,” or “third” may explicitly or implicitly include at least one of that feature. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover non-exclusive inclusion.

[0026] The over / under voltage detection circuit of this application is applicable to over / under voltage detection of electronic devices in new energy vehicles. Existing over / under voltage detection technologies often require adding algorithms to the main control chip to determine the voltage. However, main control chips are expensive and require programming and debugging, making them unsuitable for scenarios with programming and debugging difficulties and cost limitations. Furthermore, the limited number of ports on the main control chip results in poor circuit scalability.

[0027] To address the issues of high cost and poor scalability associated with the aforementioned over / under voltage detection circuits, which rely on chips, this application provides an over / under voltage detection circuit. Please refer to... Figure 1 , Figure 1 This is a schematic diagram of the framework of an embodiment of the over / under voltage detection circuit provided in this application.

[0028] The over / under voltage detection circuit 10 provided in this application includes at least one set of over / under voltage detection units 11. Each over / under voltage detection unit 11 includes: a first input power supply, a first voltage divider circuit, a second voltage divider circuit, an overvoltage detection circuit, and an undervoltage detection circuit. The input terminal of the first voltage divider circuit is connected to the first power supply, the output terminal of the first voltage divider circuit is connected to the inverting input terminal of the overvoltage detection circuit, and the non-inverting input terminal of the overvoltage detection circuit is connected to the voltage to be measured. The input terminal of the second voltage divider circuit is connected to the first power supply, the output terminal of the second voltage divider circuit is connected to the non-inverting input terminal of the undervoltage detection circuit, and the non-inverting input terminal of the undervoltage detection circuit is connected to the voltage to be measured. The first voltage divider circuit is used to divide the first input power supply to output a first reference voltage, and the second voltage divider circuit is used to divide the first input power supply to output a second reference voltage. The first reference voltage is greater than the second reference voltage.

[0029] Specifically, the first input power supply provides the power supply voltage. It can be understood that the voltage provided by the first input power supply is not less than the first reference voltage and the second reference voltage. Through the above scheme, the over / under voltage detection circuit includes at least one set of over / under voltage detection units. Each over / under voltage detection unit receives power from the first input power supply for the entire detection circuit. A first voltage divider circuit divides the first input power supply to output the first reference voltage. A second voltage divider circuit divides the first input power supply to output a second reference voltage lower than the first reference voltage. The overvoltage detection circuit compares the voltage to be measured with the first reference voltage to determine if an overvoltage condition exists. The undervoltage detection circuit compares the voltage to be measured with the second reference voltage to determine if an undervoltage condition exists. Each over / under voltage detection unit is independent and can be expanded as needed to add more detection units to monitor more voltage points, exhibiting good scalability.

[0030] In some embodiments, the over / under voltage detection unit 11 further includes a protection circuit. The input terminal of the protection circuit is connected to the detection voltage, and the voltage output by the output terminal of the protection circuit is used as the voltage to be measured. The protection circuit is located after the detection voltage to isolate and buffer the subsequent circuits of the over / under voltage detection unit 11, thereby improving the reliability and safety of the overall circuit.

[0031] Please see Figure 2 , Figure 2 This is a circuit diagram of a protection circuit according to an embodiment of the over / under voltage detection circuit provided in this application. The protection circuit includes a first resistor unit 21, a second resistor R8, and a first capacitor C3. One end of the first resistor unit 21 is connected to the detection voltage, and the other end of the first resistor unit 21 is connected to one end of the second resistor R8. The other end of the second resistor R8 is grounded. The first capacitor C3 is connected in parallel with the second resistor R8. The other end of the first resistor unit 21 serves as the output terminal of the protection circuit for outputting the voltage to be measured.

[0032] Specifically, the first resistor unit 21, the second resistor R8, and the first capacitor C3 constitute a filter circuit, used to filter out high-frequency noise or transient voltage fluctuations in the voltage, maintain the stability and accuracy of the voltage to be measured, and prevent false detections caused by voltage fluctuations. The first resistor unit 21 and the second resistor R8 divide the filtered detection voltage, and the common terminal of the first resistor unit 21 and the second resistor R8 outputs the voltage to be measured to the subsequent circuit to determine whether there is overvoltage or undervoltage.

[0033] In some specific embodiments, the first resistor unit 21 may consist of one or more resistors. In some applications, the first resistor unit 21 includes a first resistor R1 and a second resistor R3. One end of the first resistor R1 is connected to the detection voltage, and the other end of the first resistor R1 is connected to one end of the second resistor R3. The other end of the second resistor R3 is connected to the output terminal of a protection circuit for outputting the voltage to be measured. In other applications, the first resistor unit 21 may consist of at least one adjustable resistor. By adjusting the resistance values ​​of the voltage dividers in the first resistor unit 21, the input detection voltage can be divided, thereby adjusting the voltage value of the voltage to be measured output to subsequent circuits to ensure that the detection circuit can operate within a suitable voltage range.

[0034] Please see Figure 3 and Figure 4 , Figure 3 This is a circuit diagram of the first voltage divider circuit and the overvoltage detection circuit of an embodiment of the overvoltage and undervoltage detection circuit provided in this application. Figure 4 This is a circuit diagram of the second voltage divider circuit and the undervoltage detection circuit of an embodiment of the overvoltage and undervoltage detection circuit provided in this application. The first voltage divider circuit 31 includes a first voltage divider resistor R2, a second voltage divider resistor R6, and a second capacitor C2. One end of the first voltage divider resistor R2 is connected to the first power supply, and the other end of the first voltage divider resistor R2 is connected to the inverting input of the overvoltage detection circuit 32 as the output terminal of the first voltage divider circuit 31. One end of the second voltage divider resistor R6 is connected to the other end of the first voltage divider resistor R2, and the other end of the second voltage divider resistor R6 is grounded. The second capacitor C2 is connected in parallel with the second voltage divider resistor R6. The second voltage divider circuit 41 includes a third voltage divider resistor R10, a fourth voltage divider resistor R14, and a third capacitor C4. One end of the third voltage divider resistor R10 is connected to the first power supply, and the other end of the third voltage divider resistor R10 is connected to the non-inverting input of the undervoltage detection circuit 42 as the output terminal of the second voltage divider circuit 41. One end of the fourth voltage divider resistor R14 is connected to the other end of the third voltage divider resistor R10, and the other end of the fourth voltage divider resistor R14 is grounded. The third capacitor C4 is connected in parallel with the fourth voltage divider resistor R14.

[0035] Specifically, the first power supply is divided by a first voltage divider resistor R2 and a second voltage divider resistor R6. The specific voltage division ratio can be selected according to the first reference voltage value required for the specific implementation. The second capacitor C2 filters out the ripple of the input voltage after the first power supply is divided, providing a stable reference voltage for the subsequent overvoltage detection circuit 32. Similarly, the first power supply is divided by a third voltage divider resistor R10 and a fourth voltage divider resistor R14. The specific voltage division ratio can be selected according to the first reference voltage value required for the specific implementation. The third capacitor C4 filters out the ripple of the input voltage after the first power supply is divided, providing a stable reference voltage for the subsequent undervoltage detection circuit 42.

[0036] In some applications, there is a need to adjust different power supply voltage ranges and detection thresholds. To increase the flexibility of the circuit, at least one voltage divider resistor in the first voltage divider circuit 31 and the second voltage divider circuit 41 can be replaced with an adjustable resistor to meet different power management requirements.

[0037] Please see Figure 5 and Figure 6 , Figure 5 This is a circuit diagram of the first voltage divider circuit and the overvoltage detection circuit of another embodiment of the overvoltage and undervoltage detection circuit provided in this application; Figure 6 This is a circuit diagram of the second voltage divider circuit and the undervoltage detection circuit of another embodiment of the overvoltage and undervoltage detection circuit provided in this application. The first voltage divider circuit 51 includes a first adjustable resistor R2', a second adjustable resistor R6', and a second capacitor C2; one end of the first adjustable resistor R2' is connected to a first power supply, and the other end of the first adjustable resistor R2' serves as the output terminal of the first voltage divider circuit 51 and is connected to the inverting input terminal of the overvoltage detection circuit 32; one end of the second adjustable resistor R6' is connected to the other end of the first adjustable resistor R2', and the other end of the second adjustable resistor R6' is grounded; the second capacitor C2 is connected in parallel with the second adjustable resistor R6'; The voltage divider circuit 41 includes a third adjustable resistor R10', a fourth adjustable resistor R14', and a third capacitor C4. One end of the third adjustable resistor R10' is connected to the first power supply, and the other end of the third adjustable resistor R10' serves as the output terminal of the second voltage divider circuit 41 and is connected to the non-inverting input terminal of the undervoltage detection circuit. One end of the fourth adjustable resistor R14' is connected to the other end of the third adjustable resistor R10', and the other end of the fourth adjustable resistor R14' is grounded. The third capacitor C4 is connected in parallel with the fourth adjustable resistor R14'.

[0038] Specifically, the first voltage divider circuit 51 can change the voltage value after voltage division by adjusting the resistance values ​​of the first adjustable resistor and the second adjustable resistor R6'. For situations where it is necessary to change the power supply voltage or the detection voltage, the resistance value of the voltage divider resistor can be directly adjusted without re-layouting the detection circuit, thereby improving the adaptability of the over- and under-voltage detection circuit 10.

[0039] In some specific embodiments, the overvoltage detection circuit 32 includes a first operational amplifier IC1A. The inverting input terminal of the first operational amplifier IC1A is connected to the output terminal of the first voltage divider circuit 51 through a resistor R4. The non-inverting input terminal of the first operational amplifier IC1A is connected to the output terminal of the protection circuit through a resistor R7. The power supply terminal of the first operational amplifier IC1A is connected to a second power supply. The output terminal of the first operational amplifier IC1A is used to output an overvoltage signal.

[0040] Specifically, in some application scenarios, the output of the first operational amplifier IC1A outputs an undervoltage signal through a resistor R5. The first operational amplifier IC1A is used to compare the voltage to be measured with a first reference voltage. The inverting input of the first operational amplifier IC1A receives the first reference voltage output by the first voltage divider circuit 51, while the non-inverting input receives the voltage to be measured output by the protection circuit. When the voltage to be measured is higher than the first reference voltage, the output of the first operational amplifier IC1A will output a high-level signal, indicating an overvoltage condition. The power supply of the first operational amplifier IC1A is connected to a second power supply to ensure its normal operation. In some applications, both the first and second power supplies can be 5V; the specific settings can be configured according to actual needs, and this application does not impose any restrictions.

[0041] In some embodiments, the undervoltage detection circuit includes a second operational amplifier IC1B. The inverting input terminal of the second operational amplifier IC1B is connected to the output terminal of the protection circuit through a resistor R11, and the non-inverting input terminal of the second operational amplifier IC1B is connected to the output terminal of the second voltage divider circuit 41 through a resistor R13. The output terminal of the second operational amplifier IC1B is used to output an undervoltage signal.

[0042] Specifically, in some applications, the output of the second operational amplifier IC1B outputs an undervoltage signal through a resistor R12. The second operational amplifier IC1B is also used to compare the voltage to be measured with a second reference voltage. The non-inverting input of the second operational amplifier IC1B receives the second reference voltage output from the second voltage divider circuit 41, while the inverting input receives the voltage to be measured output from the protection circuit. When the voltage to be measured is lower than the second reference voltage, the output of the second operational amplifier IC1B will output a high-level signal, indicating an undervoltage condition. The undervoltage detection circuit can accurately and quickly respond to voltage drops, thereby protecting the circuit from undervoltage damage.

[0043] In some specific embodiments, the overvoltage detection circuit 32 further includes a fourth capacitor C1, one end of which is connected to the power supply terminal of the first operational amplifier IC1A, and the other end of which is grounded.

[0044] Specifically, the main function of the fourth capacitor C1 is to filter out noise and interference at the power supply end, ensuring that the first operational amplifier IC1A can operate in a stable power supply environment. This, in turn, improves the accuracy and reliability of the overvoltage detection circuit 32. Simultaneously, since power supply noise may affect the comparator's threshold voltage, adding the fourth capacitor C1 can reduce this effect, making the comparator's threshold voltage more stable.

[0045] The above scheme incorporates at least one set of over / under voltage detection units in the over / under voltage detection circuit. Each detection unit receives power from a first input power supply. A first voltage divider circuit divides the first input power supply to output a first reference voltage, and a second voltage divider circuit divides the first input power supply to output a second reference voltage lower than the first reference voltage. The overvoltage detection circuit compares the voltage to be measured with the first reference voltage to determine if an overvoltage condition exists, and the undervoltage detection circuit compares the voltage to be measured with the second reference voltage to determine if an undervoltage condition exists. Each over / under voltage detection unit is independent and can be expanded as needed to monitor more voltage points, exhibiting good scalability.

[0046] This application also provides an electronic device, please refer to [link to application]. Figure 7 , Figure 7 This is a schematic diagram of a framework of an embodiment of the electronic device provided in this application. The electronic device 70 of this embodiment includes the over / under voltage detection circuit 10 of the above embodiment. Optionally, the electronic device 70 includes devices such as power supply units in new energy vehicles that contain the over / under voltage detection circuit 10.

[0047] The above scheme incorporates at least one set of over / under voltage detection units in the over / under voltage detection circuit. Each detection unit receives power from a first input power supply. A first voltage divider circuit divides the first input power supply to output a first reference voltage, and a second voltage divider circuit divides the first input power supply to output a second reference voltage lower than the first reference voltage. The overvoltage detection circuit compares the voltage to be measured with the first reference voltage to determine if an overvoltage condition exists, and the undervoltage detection circuit compares the voltage to be measured with the second reference voltage to determine if an undervoltage condition exists. Each over / under voltage detection unit is independent and can be expanded as needed to monitor more voltage points, exhibiting good scalability.

[0048] It is understood that those skilled in the art can make equivalent substitutions or changes based on the technical solution and inventive concept of this utility model, and all such substitutions or changes should fall within the protection scope of the appended claims of this utility model.

Claims

1. An over / under voltage detection circuit, characterized in that, It includes at least one set of over-voltage and under-voltage detection units, wherein the over-voltage and under-voltage detection units include: a first input power supply, a first voltage divider circuit, a second voltage divider circuit, an over-voltage detection circuit, and an under-voltage detection circuit; The input terminal of the first voltage divider circuit is connected to the first input power supply, the output terminal of the first voltage divider circuit is connected to the inverting input terminal of the overvoltage detection circuit, and the non-inverting input terminal of the overvoltage detection circuit is connected to the voltage to be measured. The input terminal of the second voltage divider circuit is connected to the first input power supply, the output terminal of the second voltage divider circuit is connected to the non-inverting input terminal of the undervoltage detection circuit, and the non-inverting input terminal of the undervoltage detection circuit is connected to the voltage to be measured. The first voltage divider circuit is used to divide the first input power supply and output a first reference voltage, and the second voltage divider circuit is used to divide the first input power supply and output a second reference voltage, wherein the first reference voltage is greater than the second reference voltage.

2. The over / under voltage detection circuit according to claim 1, characterized in that, The over / under voltage detection unit also includes a protection circuit. The input terminal of the protection circuit is connected to the detection voltage, and the voltage output by the output terminal of the protection circuit is used as the voltage to be measured.

3. The over / under voltage detection circuit according to claim 2, characterized in that, The protection circuit includes a first resistor unit, a second resistor, and a first capacitor. One end of the first resistor unit is connected to the detected voltage, and the other end of the first resistor unit is connected to one end of the second resistor. The other end of the second resistor is grounded. The first capacitor is connected in parallel with the second resistor. The other end of the first resistor unit serves as the output terminal of the protection circuit for outputting the voltage to be measured.

4. The over / under voltage detection circuit according to claim 3, characterized in that, The first resistor unit includes a first resistor and a second resistor. One end of the first resistor is connected to the detected voltage, and the other end of the first resistor is connected to one end of the second resistor. The other end of the second resistor is connected to the output terminal of the protection circuit for outputting the voltage to be measured.

5. The over / under voltage detection circuit according to claim 2, characterized in that, The first voltage divider circuit includes a first voltage divider resistor, a second voltage divider resistor, and a second capacitor. One end of the first voltage divider resistor is connected to the first input power supply, and the other end of the first voltage divider resistor is connected to the inverting input terminal of the overvoltage detection circuit through serving as the output terminal of the first voltage divider circuit. One end of the second voltage divider resistor is connected to the other end of the first voltage divider resistor, and the other end of the second voltage divider resistor is grounded. The second capacitor is connected in parallel with the second voltage divider resistor. The second voltage divider circuit includes a third voltage divider resistor, a fourth voltage divider resistor, and a third capacitor. One end of the third voltage divider resistor is connected to the first input power supply, and the other end of the third voltage divider resistor serves as the output terminal of the second voltage divider circuit and is connected to the non-inverting input terminal of the undervoltage detection circuit. One end of the fourth voltage divider resistor is connected to the other end of the third voltage divider resistor, and the other end of the fourth voltage divider resistor is grounded. The third capacitor is connected in parallel with the fourth voltage divider resistor.

6. The over / under voltage detection circuit according to claim 2, characterized in that, The first voltage divider circuit includes a first adjustable resistor, a second adjustable resistor, and a second capacitor; one end of the first adjustable resistor is connected to the first input power supply, the other end of the first adjustable resistor serves as the output terminal of the first voltage divider circuit and is connected to the inverting input terminal of the overvoltage detection circuit, one end of the second adjustable resistor is connected to the other end of the first adjustable resistor, the other end of the second adjustable resistor is grounded, and the second capacitor is connected in parallel with the second adjustable resistor. The second voltage divider circuit includes a third adjustable resistor, a fourth adjustable resistor, and a third capacitor. One end of the third adjustable resistor is connected to the first input power supply, and the other end of the third adjustable resistor serves as the output terminal of the second voltage divider circuit and is connected to the non-inverting input terminal of the undervoltage detection circuit. One end of the fourth adjustable resistor is connected to the other end of the third adjustable resistor, and the other end of the fourth adjustable resistor is grounded. The third capacitor is connected in parallel with the fourth adjustable resistor.

7. The over / under voltage detection circuit according to claim 5 or 6, characterized in that, The overvoltage detection circuit includes a first operational amplifier. The inverting input terminal of the first operational amplifier is connected to the output terminal of the first voltage divider circuit through a resistor. The non-inverting input terminal of the first operational amplifier is connected to the output terminal of the protection circuit through a resistor. The power supply terminal of the first operational amplifier is connected to a second power supply. The output terminal of the first operational amplifier is used to output an overvoltage signal.

8. The over / under voltage detection circuit according to claim 5 or 6, characterized in that, The undervoltage detection circuit includes a second operational amplifier. The inverting input of the second operational amplifier is connected to the output of the protection circuit through a resistor, and the non-inverting input of the second operational amplifier is connected to the output of the second voltage divider circuit through a resistor. The output of the second operational amplifier is used to output an undervoltage signal.

9. The over / under voltage detection circuit according to claim 7, characterized in that, The overvoltage detection circuit also includes a fourth capacitor, one end of which is connected to the power supply terminal of the first operational amplifier, and the other end of which is grounded.

10. An electronic device, characterized in that, Includes the over / under voltage detection circuit described in any one of claims 1-9.

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