Overvoltage protection circuit and electronic equipment

Abstract

The overvoltage protection circuit comprises a detection control module and a clamping follow current module which are connected in sequence, the detection control module is used for being connected with a power source, the clamping follow current module is used for being connected with a load, and the detection control module is used for detecting the current voltage value of input power of the power source; the input power supply module is used for receiving a current voltage value and generating a starting control signal under the condition that the current voltage value is greater than a voltage threshold value, and the clamping follow current module is used for receiving the starting control signal and carrying out clamping follow current processing on the input power according to the starting control signal to obtain clamping follow current power so as to supply power to a load by adopting the clamping follow current power; according to the mode, the technical problem that the function of a post-stage circuit is interrupted during overvoltage protection of a traditional overvoltage protection circuit is effectively solved, the comprehensive performance of the whole electronic equipment in the face of power supply voltage fluctuation is remarkably improved, and multiple optimization of safety, continuity and reliability is achieved.

Description

Technical Field

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

[0002] In the operation mechanism of electronic devices, the stability of power supply voltage plays a vital role. However, in actual operation, the power supply voltage is often disturbed by multiple external factors such as power supply fluctuations and load mutations, resulting in an instantaneous increase in voltage, which in turn poses a potential threat to the subsequent circuits.

[0003] Although the traditional overvoltage protection circuit (OVP) can quickly cut off the power supply when the voltage exceeds the limit, effectively preventing the circuit from being damaged, its "one-size-fits-all" power-off strategy undoubtedly sacrifices the continuous operation capability and overall reliability of the electronic equipment, because during the protection action, the subsequent circuit will lose power supply and the function will be interrupted. Summary of the invention

[0004] Based on this, it is necessary to propose an overvoltage protection circuit and electronic equipment to address the above problems. It not only effectively solves the technical problem that the traditional overvoltage protection circuit causes the interruption of the function of the subsequent circuit during overvoltage protection, but also significantly improves the overall performance of the entire electronic equipment when facing power supply voltage fluctuations, and achieves multiple optimizations of safety, continuity and reliability.

[0005] To achieve the above object, the present invention provides an overvoltage protection circuit in a first aspect, the overvoltage protection circuit comprising a detection control module and a clamping freewheeling module connected in sequence;

[0006] The detection control module is used to connect to the power supply, and the clamping freewheeling module is used to connect to the load;

[0007] The detection control module is used to detect the current voltage value of the input power of the power supply, and generate a start control signal when the current voltage value is greater than the voltage threshold;

[0008] The clamped freewheeling module is used to receive the start-up control signal, and perform clamped freewheeling processing on the input power according to the start-up control signal to obtain clamped freewheeling power, so as to use the clamped freewheeling power to power the load.

[0009] Optionally, the detection control module is further configured to generate a shutdown control signal when the current voltage value is less than or equal to the voltage threshold;

[0010] The clamp freewheeling module is further configured to receive the shutdown control signal and use the input power to supply power to the load according to the shutdown control signal.

[0011] Optionally, the clamping freewheeling module comprises a protection switch unit and a clamping freewheeling unit connected in parallel;

[0012] The protection switch unit is connected to the detection control module;

[0013] The clamping freewheeling unit is used to be connected to the load;

[0014] The protection switch unit is used to receive the start control signal and start the clamp freewheeling state of the clamp freewheeling unit according to the start control signal;

[0015] The clamped freewheeling unit is used to perform a clamped freewheeling process on the input power to obtain the clamped freewheeling power, so as to use the clamped freewheeling power to supply power to the load;

[0016] or,

[0017] The protection switch unit is used to receive a shutdown control signal and shut down the clamp freewheeling state of the clamp freewheeling unit according to the shutdown control signal, so as to use the input power to supply power to the load.

[0018] Optionally, the clamping freewheeling unit includes a first diode;

[0019] The cathode terminal and the anode terminal of the first diode are both connected to the protection switch unit;

[0020] An anode terminal of the first diode is used to be connected to the load.

[0021] Optionally, the protection switch unit includes a second diode, a capacitor and a MOS tube;

[0022] The source terminal of the MOS tube is respectively connected to the cathode terminal of the second diode and one end of the capacitor, and the gate terminal of the MOS tube is respectively connected to the anode terminal of the second diode and the other end of the capacitor;

[0023] The drain terminal of the MOS tube is connected to the anode terminal of the first diode, the source terminal of the MOS tube is connected to the cathode terminal of the first diode, and both ends of the capacitor are connected to the detection control module.

[0024] Optionally, the detection control module includes a voltage detection unit and a control unit connected in sequence;

[0025] The control unit is connected to the source terminal and the gate terminal of the MOS tube respectively;

[0026] The voltage detection unit is used to be connected to the power supply;

[0027] The voltage detection unit is used to detect the current voltage value of the input power of the power supply, and generate a high voltage detection signal when the current voltage value is greater than the voltage threshold;

[0028] The control unit is used to generate the start control signal according to the high voltage detection signal;

[0029] or,

[0030] The voltage detection unit is used to detect the current voltage value of the input power of the power supply, and generate a low voltage detection signal when the current voltage value is less than or equal to the voltage threshold;

[0031] The control unit is used to generate the shutdown control signal according to the low voltage detection signal.

[0032] Optionally, the control unit includes a first resistor, a second resistor and a transistor;

[0033] The collector of the transistor is connected to one end of the first resistor and one end of the second resistor respectively, and the emitter of the transistor is connected to the other end of the first resistor;

[0034] The other end of the second resistor is grounded;

[0035] The emitter terminal and the base terminal of the transistor are both connected to the voltage detection unit, one end of the first resistor is connected to the other end of the capacitor, and the other end of the first resistor is connected to one end of the capacitor.

[0036] Optionally, the voltage detection unit includes a third resistor, a fourth resistor and a third diode;

[0037] The cathode terminal of the third diode is connected to one end of the third resistor and one end of the fourth resistor respectively;

[0038] The anode terminal of the third diode is grounded;

[0039] The other end of the third resistor is connected to the emitter terminal of the transistor, and the other end of the fourth resistor is connected to the base terminal of the transistor;

[0040] The other end of the third resistor is used to be connected to the power supply.

[0041] Optionally, the first diode, the second diode, and the third diode are all Zener diodes.

[0042] To achieve the above objective, the present invention provides an electronic device in a second aspect, the electronic device comprising the overvoltage protection circuit as described in any one of the first aspects.

[0043] The embodiment of the present invention has the following beneficial effects: the above-mentioned circuit comprises a detection control module and a clamping freewheeling module connected in sequence, the detection control module is used to connect to the power supply, the clamping freewheeling module is used to connect to the load, the detection control module is used to detect the current voltage value of the input power of the power supply, and when the current voltage value is greater than the voltage threshold, generates a start control signal, the clamping freewheeling module is used to receive the start control signal, and clamp the input power according to the start control signal to obtain the clamping freewheeling power, so as to use the clamping freewheeling power to power the load; that is, through the coordinated work of the carefully designed detection control module and the clamping freewheeling module, the current voltage state of the power supply is monitored in real time, and once it is detected that the current voltage exceeds the preset safety threshold, the detection control module is used to detect the current voltage value of the input power of the power supply, and generates a start control signal when the current voltage value is greater than the voltage threshold, and ... generates a start control signal when the current voltage value is greater than the voltage threshold. The full voltage threshold immediately starts the clamping mechanism to safely limit the high voltage of the previous stage to the safe voltage range that the subsequent circuit can withstand. At the same time, the freewheeling function ensures that the subsequent circuit can still obtain a continuous and stable power supply during this process, which not only ensures the circuit safety, but also greatly enhances the adaptability and operation continuity of electronic equipment in complex and changeable environments, and can comprehensively improve the operation reliability and stability of electronic equipment under power supply voltage fluctuations. That is, this method not only effectively solves the technical problem that the traditional overvoltage protection circuit causes the interruption of the subsequent circuit function during overvoltage protection, but also significantly improves the overall performance of the entire electronic equipment when facing power supply voltage fluctuations, and realizes multiple optimizations of safety, continuity and reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0045] in:

[0046] Figure 1 A schematic diagram of an overvoltage protection circuit in an embodiment of the present application Figure 1 ;

[0047] Figure 2 A schematic diagram of an overvoltage protection circuit in an embodiment of the present application Figure 2 ;

[0048] Figure 3 A schematic diagram of an overvoltage protection circuit in an embodiment of the present application Figure 3 ;

[0049] Figure 4 A schematic diagram of an overvoltage protection circuit in an embodiment of the present application Figure 4 ;

[0050] Figure 5 A schematic diagram of an overvoltage protection circuit in an embodiment of the present application Figure 5 ;

[0051] Figure 6 A schematic diagram of an overvoltage protection circuit in an embodiment of the present application Figure 6 ;

[0052] Figure 7 A schematic diagram of an overvoltage protection circuit in an embodiment of the present application Figure 7 . DETAILED DESCRIPTION

[0053] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0054] In the operation mechanism of electronic devices, the stability of power supply voltage plays a vital role. However, in actual operation, the power supply voltage is often disturbed by multiple external factors such as power supply fluctuations and load mutations, resulting in an instantaneous increase in voltage, which in turn poses a potential threat to the subsequent circuits.

[0055] Although the traditional overvoltage protection circuit (OVP) can quickly cut off the power supply when the voltage exceeds the limit, effectively preventing the circuit from being damaged, its "one-size-fits-all" power-off strategy undoubtedly sacrifices the continuous operation capability and overall reliability of the electronic equipment, because during the protection action, the subsequent circuit will lose power supply and the function will be interrupted.

[0056] In response to the above problems, the present application proposes an overvoltage protection circuit and electronic device, which not only effectively solves the technical problem that the traditional overvoltage protection circuit causes the interruption of the function of the subsequent circuit during overvoltage protection, but also significantly improves the comprehensive performance of the entire electronic device when facing power supply voltage fluctuations, and achieves multiple optimizations of safety, continuity and reliability. The specific implementation principle will be described in detail in the following embodiments.

[0057] In a first aspect, the present application provides an overvoltage protection circuit.

[0058] See also Figure 1 , which is a schematic diagram of an overvoltage protection circuit in an embodiment of the present application Figure 1 The overvoltage protection circuit includes a detection control module 110 and a clamping freewheeling module 120 which are connected in sequence.

[0059] The detection control module 110 is used to connect to the power supply 130 , and the clamping freewheeling module 120 is used to connect to the load 140 .

[0060] In a feasible implementation, the detection control module 110 is used to detect the current voltage value of the input power of the power supply 130, and generate a start control signal when the current voltage value is greater than the voltage threshold; the clamping freewheeling module 120 is used to receive the start control signal, and clamp the input power according to the start control signal to obtain clamped freewheeling power, so as to use the clamped freewheeling power to power the load 140.

[0061] The voltage threshold can be set by the operator according to actual needs.

[0062] It should be noted that the clamping and freewheeling processing includes clamping and freewheeling. In the case of input overvoltage, the overvoltage input power can be clamped to a preset safe voltage range through clamping to obtain a clamped freewheeling power. Through freewheeling, the clamped freewheeling power within the safe voltage range can be used to power the load 140, so as to achieve continuous power supply to the load 140 even in the case of overvoltage.

[0063] In some embodiments, after the input electricity of the power supply 130 is output to the detection control module 110, the detection control module 110 will detect the voltage of the input electricity to obtain the current voltage value, and then compare the current voltage value with the voltage threshold. When the current voltage value is greater than the voltage threshold, an on control signal is generated, and the on control signal is output to the clamping freewheeling module 120. At the same time, the input electricity enters the clamping freewheeling module 120 after passing through the detection control module 110. The clamping freewheeling module 120 will perform clamping freewheeling processing on the input electricity according to the on control signal to obtain clamped freewheeling electricity, and finally use the clamped freewheeling electricity to power the load 140.

[0064] In the embodiment of the present application, through the coordinated work of the carefully designed detection control module 110 and the clamping and freewheeling module 120, the current voltage state of the power supply 130 is monitored in real time. Once it is detected that the current voltage exceeds the preset safe voltage threshold, the clamping mechanism is immediately activated to safely limit the high voltage of the previous stage to a safe voltage range that the subsequent stage circuit can withstand. At the same time, the freewheeling function ensures that the subsequent stage circuit can still obtain a continuous and stable power supply during this process, thereby ensuring circuit safety and greatly enhancing the adaptability and operation continuity of electronic equipment in complex and changeable environments. It can comprehensively improve the operating reliability and stability of electronic equipment under the condition of voltage fluctuations of the power supply 130. That is, this method not only effectively solves the technical problem that the traditional overvoltage protection circuit causes the interruption of the function of the subsequent circuit during overvoltage protection, but also significantly improves the overall performance of the entire electronic device when facing voltage fluctuations of the power supply 130, and achieves multiple optimizations of safety, continuity and reliability.

[0065] In addition, the method of the present application also has the following advantages: since the overvoltage protection circuit can effectively prevent the power supply 130 voltage from being too high to damage the load 140 circuit, the failure rate of the electronic device is reduced and the frequency of repair and replacement of parts is reduced; through continuous and stable power supply and precise voltage control, it helps to extend the service life of the electronic device and its load 140 circuit; the overvoltage protection circuit highly integrates the detection control module 110 and the clamping freewheeling module 120, simplifies the overall design of the electronic device, and reduces the design cost and complexity; the design of the overvoltage protection circuit is flexible and scalable, and can be easily integrated with other electronic components to meet the needs of different applications.

[0066] In a feasible implementation, the detection control module 110 is also used to generate a shutdown control signal when the current voltage value is less than or equal to the voltage threshold; the clamping freewheeling module 120 is also used to receive the shutdown control signal and use the input power to power the load 140 according to the shutdown control signal.

[0067] In some embodiments, after the input electricity of the power supply 130 is output to the detection control module 110, the detection control module 110 will detect the voltage of the input electricity to obtain the current voltage value, and then compare the current voltage value with the voltage threshold. When the current voltage value is less than or equal to the voltage threshold, a shutdown control signal is generated and the shutdown control signal is output to the clamping and freewheeling module 120. At the same time, the input electricity enters the clamping and freewheeling module 120 after flowing through the detection control module 110. The clamping and freewheeling module 120 will not perform clamping and freewheeling processing on the input electricity according to the shutdown control signal, but directly use the input electricity to power the load 140.

[0068] In the embodiment of the present application, when the voltage of the power supply 130 is within the normal range (i.e., less than or equal to the voltage threshold), the detection control module 110 can intelligently generate a shutdown control signal, so that the clamping freewheeling module 120 directly uses the input power to power the load 140, thereby avoiding unnecessary clamping freewheeling processing, thereby improving energy utilization efficiency, and because unnecessary action of the clamping freewheeling module 120 can be avoided, the instability of the electronic device caused by malfunction is reduced, thereby enhancing the overall stability of the electronic device.

[0069] In addition, the detection control module 110 in the above embodiment can quickly detect changes in the voltage of the power supply 130 and generate corresponding control signals, so that the clamping freewheeling module 120 can quickly switch the power supply mode, thereby improving the response speed of the electronic device and ensuring that the stable power supply to the load 140 can be quickly restored when the voltage of the power supply 130 fluctuates.

[0070] based on Figure 1 , see Figure 2 , which is a schematic diagram of an overvoltage protection circuit in an embodiment of the present application Figure 2 The clamping freewheeling module 120 includes a protection switch unit 121 and a clamping freewheeling unit 122 connected in parallel.

[0071] The protection switch unit 121 is connected to the detection control module 110 ; and the clamping freewheeling unit 122 is used to be connected to the load 140 .

[0072] In a feasible implementation, the protection switch unit 121 is used to receive an on control signal, and to start the clamped freewheeling state of the clamped freewheeling unit 122 according to the on control signal; the clamped freewheeling unit 122 is used to perform clamped freewheeling processing on the input power to obtain the clamped freewheeling power, so as to use the clamped freewheeling power to power the load 140; or, the protection switch unit 121 is used to receive a off control signal, and to close the clamped freewheeling state of the clamped freewheeling unit 122 according to the off control signal, so as to use the input power to power the load 140.

[0073] In some embodiments, the start control signal output by the detection control module 110 enters the clamping freewheeling module 120. At the same time, the input electricity enters the clamping freewheeling module 120 after passing through the detection control module 110. The protection switch unit 121 will turn on the clamping freewheeling state of the clamping freewheeling unit 122 according to the start control signal, that is, close its own input electricity channel, so that the input electricity enters the clamping freewheeling unit 122, and then the clamping freewheeling unit 122 performs clamping freewheeling processing on the input electricity to obtain clamping freewheeling electricity, and finally the clamping freewheeling electricity is used to power the load 140.

[0074] In other embodiments, the shutdown control signal output by the detection control module 110 enters the clamping freewheeling module 120. At the same time, the input electricity enters the clamping freewheeling module 120 after flowing through the detection control module 110. The protection switch unit 121 will close the clamping freewheeling state of the clamping freewheeling unit 122 according to the shutdown control signal, that is, open its own input electricity channel so that the input electricity does not enter the clamping freewheeling unit 122. Then, the clamping freewheeling unit 122 does not perform clamping freewheeling processing on the input electricity, but the protection switch unit 121 directly uses the input electricity to power the load 140.

[0075] In the embodiment of the present application, by subdividing the clamping freewheeling module 120 into a protection switch unit 121 and a clamping freewheeling unit 122, the protection switch unit 121 can quickly respond to the on or off control signal issued by the detection control module 110, and promptly turn on or off the clamping freewheeling state. This fast response mechanism ensures that protective measures can be taken quickly when the voltage of the power supply 130 fluctuates, effectively preventing damage to the subsequent circuit of the load 140 caused by excessive voltage of the power supply 130.

[0076] In addition, through the coordinated work of the carefully designed protection switch unit 121 and the clamping freewheeling unit 122, a stable power supply can be maintained when the voltage of the power supply 130 fluctuates. This stability is crucial for the normal operation of electronic equipment and helps to extend the service life of electronic equipment and improve its overall performance.

[0077] based on Figure 2 , see Figure 3 , which is a schematic diagram of an overvoltage protection circuit in an embodiment of the present application Figure 3 , the clamping freewheeling unit 122 includes a first diode D1.

[0078] In a feasible implementation, both the cathode terminal and the anode terminal of the first diode D1 are connected to the protection switch unit 121 ; and the anode terminal of the first diode D1 is used to be connected to the load 140 .

[0079] In some embodiments, when the protection switch unit 121 turns on the clamping freewheeling state of the clamping freewheeling unit 122 according to the start control signal, that is, closes its own input power channel, the input power enters the clamping freewheeling unit 122 and flows in from the cathode end of the first diode D1, and then the first diode D1 clamps the input power to obtain clamped freewheeling power, and the clamped freewheeling power flows out from the anode end of the first diode D1 to power the load 140.

[0080] In the embodiment of the present application, by adopting the first diode D1 as the core component of the clamping freewheeling unit 122, the overvoltage protection circuit of the present application shows significant advantages in simplifying circuit design, reducing costs, improving circuit response speed, enhancing circuit stability, facilitating integration and maintenance, and improving energy utilization efficiency.

[0081] It can be understood that the circuit design is simplified and the cost is reduced: by adopting the first diode D1 as the core component of the clamping freewheeling unit 122, the design of the overvoltage protection circuit is greatly simplified. As a basic device in electronic components, the first diode D1 has a relatively low cost and is easy to purchase and integrate, which helps to reduce the manufacturing cost of the entire electronic device; improve the circuit response speed: the first diode D1 has a fast turn-on and turn-off characteristic, and can respond quickly after receiving the control signal of the protection switch unit 121 to turn on or off the clamping freewheeling state. This fast response mechanism ensures that measures can be taken quickly when the power supply 130 voltage fluctuates, effectively preventing damage to the load 140 subsequent circuit caused by the excessive voltage of the power supply 130; enhance circuit stability: the clamping freewheeling function of the first diode D1 can stabilize the power supply 13 0 voltage, limiting it within a safe range. Even if the voltage of the power supply 130 increases instantaneously, the first diode D1 can reduce the voltage to a level that the subsequent circuit of the load 140 can withstand through its clamping effect, thereby ensuring the stable operation of the electronic equipment; easy integration and maintenance: since the first diode D1 is a standard electronic component, it is small in size and light in weight, and is easy to integrate with other electronic components. At the same time, the first diode D1 has high reliability and stability and is not prone to failure, thereby reducing the maintenance cost of the electronic equipment; improving energy utilization efficiency: when the voltage of the power supply 130 is within a normal range, the first diode D1 does not participate in the clamping freewheeling process, but the protection switch unit 121 directly uses the input power to power the load 140. This design avoids unnecessary energy consumption and improves energy utilization efficiency.

[0082] based on Figure 3 , see Figure 4 , which is a schematic diagram of an overvoltage protection circuit in an embodiment of the present application Figure 4 The protection switch unit 121 includes a second diode D2, a capacitor C1 and a MOS tube Q1.

[0083] In a feasible implementation, the source terminal of the MOS tube Q1 is respectively connected to the cathode terminal of the second diode D2 and one end of the capacitor C1, and the gate terminal of the MOS tube Q1 is respectively connected to the anode terminal of the second diode D2 and the other end of the capacitor C1; the drain terminal of the MOS tube Q1 is connected to the anode terminal of the first diode D1, the source terminal of the MOS tube Q1 is connected to the cathode terminal of the first diode D1, and both ends of the capacitor C1 are connected to the detection control module 110.

[0084] In some embodiments, after the protection switch unit 121 receives the start control signal, the MOS tube Q1 is turned off to close its own input power channel, so that the input power enters the clamping freewheeling unit 122 and flows in from the cathode end of the first diode D1. Then the first diode D1 clamps the input power to obtain clamped freewheeling power. The clamped freewheeling power flows out from the anode end of the first diode D1 to power the load 140.

[0085] In other embodiments, after the protection switch unit 121 receives the shutdown control signal, the MOS tube Q1 is turned on to open its own input power channel so that the input power does not enter the clamping freewheeling unit 122, and then the first diode D1 does not clamp the input power (i.e., the first diode D1 is short-circuited), but the input power is output from the drain end of the MOS tube to directly use the input power to power the load 140.

[0086] In the embodiment of the present application, by adopting the protection switch unit 121 composed of the second diode D2, the capacitor C1 and the MOS tube Q1, the overvoltage protection circuit of the present application shows significant advantages in terms of fast response, precise control, circuit stability, energy utilization efficiency, integration and maintenance convenience, and circuit reliability.

[0087] It can be understood that fast response and precise control: by combining the second diode D2, the capacitor C1 and the MOS tube Q1, the protection switch unit 121 can quickly respond to the on or off control signal issued by the detection control module 110, and the capacitor C1 plays a role in stabilizing the signal, which helps to reduce signal fluctuations and ensure that the MOS tube Q1 can be accurately and quickly turned on or off, thereby achieving precise control of the clamping freewheeling state; the coordinated work of the second diode D2 and the capacitor C1 helps to suppress the fluctuation of the power supply 130 voltage and provide a more stable control environment for the MOS tube Q1, which helps to reduce the malfunction caused by the unstable voltage of the power supply 130, and further improves the stability of the entire overvoltage protection circuit; improve energy utilization efficiency: when receiving the shutdown control signal, the MOS tube Q1 can be quickly turned on to make the input The input power is directly supplied to the load 140 through the protection switch unit 121, avoiding unnecessary clamping and freewheeling processing. This design helps to reduce energy consumption and improve energy utilization efficiency; easy integration and maintenance: the second diode D2, capacitor C1 and MOS tube Q1 are standard electronic components with small size and light weight, which are easy to integrate with other electronic components. At the same time, these components have high reliability and stability and are not prone to failure, thereby reducing the maintenance cost of electronic equipment; improving circuit reliability: through reasonable circuit design and component selection, the protection switch unit 121 can maintain stable performance in the harsh power supply 130 environment. Even if the power supply 130 voltage increases instantly, the protection switch unit 121 can respond quickly and reduce the voltage to a safe range, thereby ensuring the stable operation of the electronic equipment.

[0088] based on Figure 4 , see Figure 5 , which is a schematic diagram of an overvoltage protection circuit in an embodiment of the present application Figure 5 The detection control module 110 includes a voltage detection unit 111 and a control unit 112 which are connected in sequence.

[0089] The control unit 112 is connected to the source terminal and the gate terminal of the MOS tube Q1 respectively; the voltage detection unit 111 is used to connect to the power supply 130.

[0090] In a feasible implementation, the voltage detection unit 111 is used to detect the current voltage value of the input electricity of the power supply 130, and generate a high voltage detection signal when the current voltage value is greater than the voltage threshold; the control unit 112 is used to generate a start control signal based on the high voltage detection signal; or, the voltage detection unit 111 is used to detect the current voltage value of the input electricity of the power supply 130, and generate a low voltage detection signal when the current voltage value is less than or equal to the voltage threshold; the control unit 112 is used to generate a shutdown control signal based on the low voltage detection signal.

[0091] In some embodiments, after the input electricity of the power supply 130 is output to the detection control module 110, the voltage detection unit 111 detects the voltage of the input electricity to obtain a current voltage value, and then compares the current voltage value with a voltage threshold. When the current voltage value is greater than the voltage threshold, a high voltage detection signal is generated, and the high voltage detection signal is output to the control unit 112. The control unit 112 generates a start control signal according to the high voltage detection signal, and outputs the start control signal to the MOS tube Q1. At the same time, the input electricity enters the first diode D1 after flowing through the voltage detection unit 111 and the control unit 112.

[0092] In other embodiments, after the input electricity of the power supply 130 is output to the detection control module 110, the voltage detection unit 111 detects the voltage of the input electricity to obtain a current voltage value, and then compares the current voltage value with the voltage threshold. When the current voltage value is less than or equal to the voltage threshold, a low voltage detection signal is generated, and the low voltage detection signal is output to the control unit 112. The control unit 112 generates a shutdown control signal based on the low voltage detection signal, and outputs the shutdown control signal to the MOS tube Q1. At the same time, the input electricity enters the MOS tube Q1 after flowing through the voltage detection unit 111 and the control unit 112.

[0093] In the embodiment of the present application, by subdividing the detection control module 110 into a voltage detection unit 111 and a control unit 112, the voltage detection unit 111 can detect the input voltage of the power supply 130 in real time and accurately. Once it is detected that the voltage exceeds the preset safety range (that is, greater than the voltage threshold), a high voltage detection signal is immediately generated, and the control unit 112 quickly generates an open control signal based on this signal to trigger the protection mechanism. This ability of accurate detection and rapid response ensures that the electronic device can quickly take protective measures when the voltage of the power supply 130 fluctuates, effectively preventing damage to the subsequent circuit of the load 140 caused by overvoltage, and when the voltage of the power supply 130 is within the normal range (that is, less than or equal to the voltage threshold), the voltage detection unit 111 generates a low voltage detection signal, and the control unit 112 generates a close control signal based on this signal, so that the protection switch unit 121 directly uses the input power to power the load 140, avoiding unnecessary clamping and freewheeling processing. This intelligent control strategy not only improves energy utilization efficiency, but also reduces circuit complexity and energy consumption.

[0094] In addition, through the coordinated work of the carefully designed voltage detection unit 111 and the control unit 112, a stable power supply can be maintained when the voltage of the power supply 130 fluctuates. This stability is essential for the normal operation of electronic devices and helps to extend the service life of electronic devices and improve their overall performance.

[0095] based on Figure 5, see Figure 6 , which is a schematic diagram of an overvoltage protection circuit in an embodiment of the present application Figure 6 The control unit 112 includes a first resistor R1, a second resistor R2 and a transistor Q2.

[0096] In a feasible implementation, the collector of the transistor Q2 is respectively connected to one end of the first resistor R1 and one end of the second resistor R2, and the emitter end of the transistor Q2 is connected to the other end of the first resistor R1; the other end of the second resistor R2 is grounded; the emitter end and the base end of the transistor Q2 are both connected to the voltage detection unit 111, one end of the first resistor R1 is connected to the other end of the capacitor C1, and the other end of the first resistor R1 is connected to one end of the capacitor C1.

[0097] In some embodiments, after the voltage detection unit 111 outputs the high voltage detection signal to the control unit 112, the transistor Q2 is turned on, so that the start-up control signal output by the collector end of the transistor Q2 is a high-level signal, so as to output the high-level signal to the MOS tube Q1, thereby turning off the MOS tube Q1.

[0098] In other embodiments, after the voltage detection unit 111 outputs the low voltage detection signal to the control unit 112, the transistor Q2 is turned off, so that the shutdown control signal output by the collector end of the transistor Q2 is a low-level signal, so as to output the low-level signal to the MOS tube Q1, thereby turning on the MOS tube Q1.

[0099] In the embodiment of the present application, by adopting a control unit 112 composed of a first resistor R1, a second resistor R2 and a transistor Q2, the overvoltage protection circuit of the present application shows significant advantages in terms of fast response, stability, precise control and circuit simplicity, which helps to improve the overall performance and reliability of electronic equipment.

[0100] It can be understood that fast response: the transistor Q2, as an electronic switch, has fast turn-on and turn-off characteristics, and can respond quickly after receiving the high voltage detection signal or the low voltage detection signal of the voltage detection unit 111, and realizes fast control of the MOS tube Q1 by changing the output level (high level or low level) of its collector, so as to quickly turn on or off the clamping freewheeling state. This fast response mechanism helps to take measures quickly when the voltage of the power supply 130 fluctuates to protect the subsequent circuit of the load 140 from damage; stability and precise control: by reasonably designing the resistance values ​​of the first resistor R1 and the second resistor R2, as well as the selection of the transistor Q2, the turn-on and turn-off conditions of the transistor Q2 can be accurately controlled to ensure that when the voltage of the power supply 130 exceeds The protection mechanism can be accurately triggered within the preset safety range. At the same time, the collector output level of the transistor Q2 is stable, which helps to reduce signal fluctuations and improve the stability of the entire overvoltage protection circuit; circuit simplicity: the control unit 112 composed of the first resistor R1, the second resistor R2 and the transistor Q2 has higher circuit simplicity than other complex control circuits. This simplicity not only helps to reduce manufacturing costs, but also facilitates circuit design, debugging and maintenance; strong adaptability: since components such as the transistor Q2, the first resistor R1 and the second resistor R2 are standard electronic components, they are easy to purchase and integrate. Therefore, the control unit 112 of the present application has strong adaptability and can be easily integrated with other electronic components to meet the needs of different applications.

[0101] based on Figure 6 , see Figure 7 , which is a schematic diagram of an overvoltage protection circuit in an embodiment of the present application Figure 7 The voltage detection unit 111 includes a third resistor R3, a fourth resistor R4 and a third diode D3.

[0102] In a feasible implementation, the cathode end of the third diode D3 is respectively connected to one end of the third resistor R3 and one end of the fourth resistor R4; the anode end of the third diode D3 is grounded; the other end of the third resistor R3 is connected to the emitter end of the transistor Q2, and the other end of the fourth resistor R4 is connected to the base end of the transistor Q2; the other end of the third resistor R3 is used to connect to the power supply 130.

[0103] In some embodiments, after the input electricity of the power supply 130 is output to the detection control module 110, that is, after the input electricity enters the voltage detection unit 111, the third diode D3 is reversely conducted, and the high voltage detection signal output by the fourth resistor R4 is a high-level signal, so as to output the high-level signal to the transistor Q2, thereby turning on the transistor Q2, thereby turning off the MOS tube Q1.

[0104] In other embodiments, after the input electricity of the power supply 130 is output to the detection control module 110, that is, after the input electricity enters the voltage detection unit 111, the third diode D3 is reversely cut off, and the low voltage detection signal output by the fourth resistor R4 is a low-level signal, so as to output the low-level signal to the transistor Q2, thereby cutting off the transistor Q2, thereby turning on the MOS tube Q1.

[0105] In the embodiment of the present application, by adopting the voltage detection unit 111 composed of the third resistor R3, the fourth resistor R4 and the third diode D3, the overvoltage protection circuit of the present application shows significant advantages in terms of accurate voltage detection, fast response, high stability, circuit simplicity and strong adaptability.

[0106] It can be understood that, accurate voltage detection: through the combination of the third resistor R3 and the third diode D3, the input voltage of the power supply 130 can be accurately detected. When the input voltage rises to a certain level, the third diode D3 is reversely conducted, and a high-level high-voltage detection signal can be output through the fourth resistor R4. This signal can accurately reflect that the input voltage has exceeded the preset safety range; fast response: the third diode D3, as an electronic component, has a fast response characteristic. When the input voltage changes, the third diode D3 can quickly change its conduction state, thereby outputting a corresponding detection signal through the fourth resistor R4. This fast response capability helps to quickly trigger the protection mechanism when the voltage of the power supply 130 fluctuates, thereby protecting the subsequent circuit of the load 140 from damage; high stability: by reasonably designing the third resistor R3 and the third diode D3, the third diode D3 can quickly change its conduction state, thereby outputting a corresponding detection signal through the fourth resistor R4. The resistance values ​​of the four resistors R4 and the selection of the third diode D3 can ensure that the voltage detection unit 111 maintains stable performance when the voltage of the power supply 130 fluctuates. This stability helps to reduce false operations and improve the reliability of the entire overvoltage protection circuit; circuit simplicity: the voltage detection unit 111 composed of the third resistor R3, the fourth resistor R4 and the third diode D3 has higher circuit simplicity than other complex detection circuits. This simplicity not only helps to reduce manufacturing costs, but also facilitates circuit design, debugging and maintenance; strong adaptability: since components such as the third resistor R3, the fourth resistor R4 and the third diode D3 are standard electronic components, they are easy to purchase and integrate. Therefore, the voltage detection unit 111 of the present application has strong adaptability and can be easily integrated with other electronic components to meet the needs of different applications.

[0107] In a feasible implementation, the first diode D1 , the second diode D2 , and the third diode D3 are all Zener diodes.

[0108] In the embodiment of the present application, by selecting the first diode D1, the second diode D2, and the third diode D3 as Zener diodes, it not only helps to improve the stability and response speed of the overvoltage protection circuit, but also helps to reduce the manufacturing cost and maintenance cost of the electronic device. This implementation method has broad application prospects in electronic devices.

[0109] It can be understood that stable voltage clamping characteristics: Zener diodes have significant voltage clamping characteristics, that is, in the reverse breakdown voltage region, their voltage remains basically unchanged, which means that when the voltage of the power supply 130 increases and exceeds the breakdown voltage of the Zener diode, the Zener diode can limit the voltage to near its breakdown voltage, thereby protecting the subsequent circuit from overvoltage damage. This stable voltage clamping characteristic is essential to ensure the stable operation of electronic equipment; fast response speed: Zener diodes have a fast response speed and can change from the off state to the on state, or from the on state to the off state in a very short time. The fast response speed helps to take quick measures when the voltage of the power supply 130 fluctuates, so as to protect the subsequent circuits of the load 140 from damage; easy integration and maintenance: as a standard electronic component, the Zener diode is small in size and light in weight, and is easy to integrate with other electronic components. At the same time, the Zener diode has high reliability and stability and is not prone to failure, thereby reducing the maintenance cost of the electronic equipment; cost-effectiveness: as a commonly used electronic component, the Zener diode has a relatively low production cost and is easy to purchase and integrate. Selecting the Zener diode as the implementation method of the diode type in this application helps to reduce the manufacturing cost of the entire electronic equipment.

[0110] In a second aspect, the present application provides an electronic device, which includes an overvoltage protection circuit as described in any one of the first aspects.

[0111] It should be noted that the electronic device of the present application includes not only the overvoltage protection circuit in the above-mentioned embodiment, but also, in practical applications, the electronic device may also include other circuits, elements, devices, components and other structures of existing electronic devices, which will not be described in detail here.

[0112] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0113] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. An overvoltage protection circuit, characterized in that: The overvoltage protection circuit comprises a detection control module and a clamping freewheeling module connected in sequence; The detection control module is used to connect to the power supply, and the clamping freewheeling module is used to connect to the load; The detection control module is used to detect the current voltage value of the input power of the power supply, and generate a start control signal when the current voltage value is greater than the voltage threshold; The clamped freewheeling module is used to receive the start-up control signal, and perform clamped freewheeling processing on the input power according to the start-up control signal to obtain clamped freewheeling power, so as to use the clamped freewheeling power to power the load.

2. The overvoltage protection circuit according to claim 1, characterized in that: The detection control module is further configured to generate a shutdown control signal when the current voltage value is less than or equal to the voltage threshold; The clamp freewheeling module is further configured to receive the shutdown control signal and use the input power to supply power to the load according to the shutdown control signal.

3. The overvoltage protection circuit according to claim 1 or 2, characterized in that: The clamping freewheeling module comprises a protection switch unit and a clamping freewheeling unit connected in parallel; The protection switch unit is connected to the detection control module; The clamping freewheeling unit is used to be connected to the load; The protection switch unit is used to receive the start control signal and start the clamp freewheeling state of the clamp freewheeling unit according to the start control signal; The clamped freewheeling unit is used to perform a clamped freewheeling process on the input power to obtain the clamped freewheeling power, so as to use the clamped freewheeling power to supply power to the load; or, The protection switch unit is used to receive a shutdown control signal and shut down the clamp freewheeling state of the clamp freewheeling unit according to the shutdown control signal, so as to use the input power to supply power to the load.

4. The overvoltage protection circuit according to claim 3, characterized in that: The clamping freewheeling unit comprises a first diode; The cathode terminal and the anode terminal of the first diode are both connected to the protection switch unit; An anode terminal of the first diode is used to be connected to the load.

5. The overvoltage protection circuit according to claim 4, characterized in that: The protection switch unit includes a second diode, a capacitor and a MOS tube; The source terminal of the MOS tube is respectively connected to the cathode terminal of the second diode and one end of the capacitor, and the gate terminal of the MOS tube is respectively connected to the anode terminal of the second diode and the other end of the capacitor; The drain terminal of the MOS tube is connected to the anode terminal of the first diode, the source terminal of the MOS tube is connected to the cathode terminal of the first diode, and both ends of the capacitor are connected to the detection control module.

6. The overvoltage protection circuit according to claim 5, characterized in that: The detection control module includes a voltage detection unit and a control unit connected in sequence; The control unit is connected to the source terminal and the gate terminal of the MOS tube respectively; The voltage detection unit is used to be connected to the power supply; The voltage detection unit is used to detect the current voltage value of the input power of the power supply, and generate a high voltage detection signal when the current voltage value is greater than the voltage threshold; The control unit is used to generate the start control signal according to the high voltage detection signal; or, The voltage detection unit is used to detect the current voltage value of the input power of the power supply, and generate a low voltage detection signal when the current voltage value is less than or equal to the voltage threshold; The control unit is used to generate the shutdown control signal according to the low voltage detection signal.

7. The overvoltage protection circuit according to claim 6, characterized in that: The control unit includes a first resistor, a second resistor and a triode; The collector of the transistor is connected to one end of the first resistor and one end of the second resistor respectively, and the emitter of the transistor is connected to the other end of the first resistor; The other end of the second resistor is grounded; The emitter terminal and the base terminal of the transistor are both connected to the voltage detection unit, one end of the first resistor is connected to the other end of the capacitor, and the other end of the first resistor is connected to one end of the capacitor.

8. The overvoltage protection circuit according to claim 7, characterized in that: The voltage detection unit includes a third resistor, a fourth resistor and a third diode; The cathode terminal of the third diode is connected to one end of the third resistor and one end of the fourth resistor respectively; The anode terminal of the third diode is grounded; The other end of the third resistor is connected to the emitter terminal of the transistor, and the other end of the fourth resistor is connected to the base terminal of the transistor; The other end of the third resistor is used to be connected to the power supply.

9. The overvoltage protection circuit according to claim 8, characterized in that: The first diode, the second diode and the third diode are all Zener diodes.

10. An electronic device, characterized in that: The electronic device comprises the overvoltage protection circuit according to any one of claims 1 to 9.

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