Power supply circuit and electronic device

Abstract

The application discloses a power supply circuit and electronic equipment, the power supply circuit includes overvoltage protection circuit and power supply indication circuit, one end of the overvoltage protection circuit is coupled with a power input end, and the other end is coupled with a power output end; the power supply indication circuit is coupled with the overvoltage protection circuit, and the power supply indication circuit comprises an indicating device and a voltage stabilizing circuit, one end of the voltage stabilizing circuit is coupled with the overvoltage protection circuit, and the other end of the voltage stabilizing circuit is coupled with the indicating device.Above-mentioned, by coupling the overvoltage protection circuit between the power input end and the power supply indication circuit, the overvoltage protection circuit can inhibit the transient overvoltage surge, can clamp the lightning high voltage to a safe value when lightning occurs, reduce the problem of lightning damage to the power supply indication circuit, and the overvoltage protection circuit can also quickly release the electric charge and reduce the static damage.

Description

Technical Field

[0001] This utility model relates to the field of electronic equipment technology, and in particular to a power supply circuit and electronic equipment. Background Technology

[0002] With the development of technology, the types of electronic devices are increasing, such as chargers, power strips, home audio-visual equipment, and small appliances. Power supply circuits are widely used in electronic devices. Power supply circuits with power indicator functions facilitate monitoring their operating status. Related technologies propose a power supply circuit, but in these cases, the power supply circuit is not protected against lightning or static electricity, and the power indicator circuit is easily damaged by lightning strikes and static electricity. Utility Model Content

[0003] The main technical problem this application addresses is to provide a power supply circuit and electronic device that can reduce damage to the power indicator circuit from lightning strikes and electrostatic discharge.

[0004] To address the aforementioned problems, this application provides a power supply circuit, which includes an overvoltage protection circuit and a power indicator circuit. One end of the overvoltage protection circuit is coupled to a power input terminal, and the other end is coupled to a power output terminal. The power indicator circuit is coupled to the overvoltage protection circuit and includes an indicator device and a voltage regulator circuit. One end of the voltage regulator circuit is coupled to the overvoltage protection circuit, and the other end of the voltage regulator circuit is coupled to the indicator device.

[0005] By setting up an overvoltage protection circuit, transient overvoltage surges can be suppressed. In the event of a lightning strike, the high voltage of the lightning strike can be clamped to a safe value, reducing the problem of lightning strikes damaging the power indicator circuit. The overvoltage protection circuit can also quickly release charge, reducing electrostatic damage.

[0006] In one possible implementation, the overvoltage protection circuit includes a varistor coupled to the power input terminal.

[0007] Varistors offer excellent protection against lightning strikes and electrostatic discharge (ESD) damage. In the event of a lightning strike, when the instantaneous voltage exceeds the varistor's voltage regulation, its resistance drops sharply to the ohm level, creating a low-resistance path that guides the current to ground, thus preventing lightning damage. When static electricity is generated, the varistor absorbs energy and quickly clamps the current, reducing the harmful effects of electrostatic discharge.

[0008] In one possible implementation, the power indicator circuit further includes an energy storage filter capacitor, which is connected in parallel with the voltage regulator circuit.

[0009] By using a voltage regulator circuit instead of a transformer to step down the voltage and supply power to the indicator device, the amount of electricity stored in the energy storage filter capacitor can be reduced, and the energy storage and discharge speed of the energy storage filter capacitor can be accelerated, thereby improving the problem of delayed changes in the brightness of the light-emitting diode.

[0010] In one possible implementation, the voltage regulator circuit includes: a Zener diode; a transistor, the input terminal of which is coupled to the overvoltage protection circuit, the output terminal of which is coupled to the indicator device, the control terminal of which is coupled to the cathode of the Zener diode, the anode of which is grounded; and a voltage regulator resistor, one end of which is coupled to the overvoltage protection circuit, and the other end of which is coupled between the control terminal and the cathode of the Zener diode.

[0011] The voltage regulator circuit described above can reduce the amount of electricity stored in the energy storage filter capacitor.

[0012] In one possible implementation, the power indicator circuit further includes a rectifier circuit, and the voltage regulator circuit is coupled to the overvoltage protection circuit through the rectifier circuit.

[0013] A rectifier circuit is used to convert the alternating current input at the source input terminal into direct current to power the indicating device.

[0014] In one possible implementation, the rectifier circuit includes a half-wave rectifier diode, the anode of which is coupled to the overvoltage protection circuit, and the cathode of which is coupled to the voltage regulator circuit.

[0015] The above can convert AC to DC.

[0016] In one possible implementation, the power indicator circuit further includes a current limiting circuit, and the voltage regulator circuit is coupled to the overvoltage protection circuit through the current limiting circuit.

[0017] Current limiting circuits can reduce the problem of excessive current.

[0018] In one possible implementation, the power indicator circuit further includes a high-frequency filter circuit, which is connected in parallel with the voltage regulator circuit.

[0019] It can remove high-frequency signals and serve as a circuit protection function.

[0020] In one possible implementation, the power supply circuit further includes a protection circuit, wherein the overvoltage protection circuit is coupled to the power input terminal.

[0021] It can effectively reduce the problem of short circuits in overvoltage protection circuits caused by multiple surge impacts and continuous overvoltage, thus preventing safety accidents.

[0022] To address the aforementioned problems, this application also provides an electronic device that includes the aforementioned power supply circuit.

[0023] The beneficial effects of this application are: by coupling an overvoltage protection circuit between the power input terminal and the power indicator circuit, the overvoltage protection circuit can suppress transient overvoltage surges, clamp the high voltage of lightning strikes to a safe value in the event of a lightning strike, reduce the problem of lightning strikes damaging the power indicator circuit, and the overvoltage protection circuit can also quickly release charge, reducing electrostatic damage. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure of the power supply circuit of the first embodiment of this application;

[0026] Figure 2 This is a schematic diagram of the structure of the power supply circuit of the second embodiment of this application;

[0027] Figure 3 This is a schematic diagram of the third embodiment of the power supply circuit of this application.

[0028] Figure label:

[0029] 100. Power supply circuit; 10. Power input terminal; 20. Overvoltage protection circuit; 21. Varistor; 30. Power output terminal; 40. Power indicator circuit; 50. Fuse; 41. Rectifier circuit; 411. Half-wave rectifier diode; 42. Current limiting circuit; 43. Voltage regulator circuit; 431. Zener diode; 432. Transistor; 433. Voltage regulator resistor; 44. High-frequency filter circuit; 45. Indicator; 46. Energy storage filter capacitor. Detailed Implementation

[0030] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this patent.

[0031] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to limit the application. The singular forms “a,” “said,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms, unless otherwise clearly indicated above. “Multiple” generally includes at least two, but does not exclude the inclusion of at least one.

[0032] It should be understood that the term "and / or" used herein is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Furthermore, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship. The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0033] It should be understood that the terms "comprising," "including," or any other variations used herein are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0034] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in every place in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0035] The existing power supply circuit is not protected against lightning or static electricity, and the power indicator circuit is easily damaged by lightning strikes and static electricity.

[0036] To address the technical problems, this application provides a power supply circuit and an electronic device. This power supply circuit includes an overvoltage protection circuit, which effectively solves the aforementioned technical problems.

[0037] For ease of explanation, please refer to the following examples. Figures 1 to 3 , Figure 1 This is a schematic diagram of the structure of the power supply circuit of the first embodiment of this application; Figure 2 This is a schematic diagram of the structure of the power supply circuit of the second embodiment of this application; Figure 3This is a schematic diagram of the third embodiment of the power supply circuit of this application.

[0038] In one specific embodiment, the power supply circuit 100 includes an overvoltage protection circuit 20 and a power indicator circuit 40. One end of the overvoltage protection circuit 20 is coupled to the power input terminal 10, and the other end is coupled to the power output terminal 30; the power indicator circuit 40 is coupled to the overvoltage protection circuit 20. The power indicator circuit 40 includes an indicator device 45 and a voltage regulator circuit 43, one end of the voltage regulator circuit 43 is coupled to the overvoltage protection circuit 20, and the other end of the voltage regulator circuit 43 is coupled to the indicator device 45.

[0039] The power input terminal 10 is used to connect to the mains high voltage. The overvoltage protection circuit 20 can provide overvoltage protection, such as lightning strike and surge protection, interruption of continuous high voltage, and electrostatic discharge. In this embodiment, the power output terminal 30 is coupled to the overvoltage protection circuit 20 and is used to couple to electrical devices or external equipment to supply power to them. The power indicator circuit 40 is coupled to the overvoltage protection circuit 20 and may include an indicator device 45, which may specifically be a light-emitting diode (LED) (not shown). By setting the power indicator circuit 40, the energization status of the power supply circuit 100 can be quickly obtained. For example, when the LED is emitting light, the power supply circuit 100 is in an energized state; when the LED is not emitting light, the power supply circuit 100 is in an de-energized state.

[0040] Unlike existing technologies, this application proposes a power supply circuit 100, which couples an overvoltage protection circuit 20 between the power input terminal 10 and the power indicator circuit 40. The overvoltage protection circuit 20 can suppress transient overvoltage surges and clamp the high voltage of a lightning strike to a safe value in the event of a lightning strike, reducing the problem of lightning damage to the power indicator circuit 40. The overvoltage protection circuit 20 can also quickly release charge, reducing electrostatic damage.

[0041] In some embodiments, the overvoltage protection circuit 20 includes a varistor 21, which is coupled to the power input terminal 10.

[0042] In this embodiment, the overvoltage protection circuit 20 uses a varistor 21 for overvoltage protection. The varistor 21 is an electronic component with nonlinear voltage-current characteristics; its resistance changes with the voltage across it. The varistor 21 exhibits nonlinear volt-ampere characteristics and transient response capability. It provides excellent protection against lightning strikes and electrostatic discharge (ESD). When an overvoltage occurs at the power input terminal 10, such as during a lightning strike, a momentary voltage is generated, causing the voltage across the varistor 21 to exceed its varistor voltage. The varistor 21 then conducts, diverting the abnormal current to ground or dissipating energy, thereby limiting the voltage peak and achieving lightning protection. When static electricity is generated, the varistor 21 absorbs energy and clamps quickly, reducing the hazards of static electricity. In this embodiment, the varistor 21 is a zinc oxide varistor; in some other embodiments, it can also be a silicon carbide varistor. Furthermore, the varistor 21 can be directly connected in parallel between the positive and negative terminals of the power input terminal 10. In this embodiment, the overvoltage protection circuit 20 provides overvoltage protection by setting a varistor 21. In some other embodiments, the overvoltage protection circuit 20 can also provide overvoltage protection by setting other structures such as transient suppression diodes, overvoltage protection chips, and gas discharge tubes. Furthermore, in some preferred embodiments, a fuse 50 is also provided between the power input terminal 10 and the varistor 21. Setting the fuse 50 can effectively prevent the varistor 21 from short-circuiting under repeated surge impacts and continuous overvoltage, thus avoiding safety accidents.

[0043] In some embodiments, the power indicator circuit 40 further includes an energy storage filter capacitor 46, which is connected in parallel with the voltage regulator circuit 43.

[0044] The indicator 45 can be a light-emitting diode (LED), a liquid crystal display module, etc. By setting the indicator 45, the power-on status of the power supply circuit 100 can be quickly obtained. For example, when the LED is emitting light, the power supply circuit 100 is in a powered-on state; when the LED is not emitting light, the power supply circuit 100 is in a powered-off state. The voltage regulator circuit 43 is coupled to the overvoltage protection circuit 20. The voltage regulator circuit 43 is used to stabilize the high voltage input to the power input terminal 10 to a low voltage. The voltage regulator circuit 43 also plays a role in stabilizing the voltage, effectively reducing indication abnormalities caused by input voltage fluctuations, and improving the reliability of the power indicator. The energy storage filter capacitor 46 can play the roles of energy storage, voltage stabilization, and filtering. The parallel setting of the energy storage filter capacitor 46 can reduce voltage ripple, improve the power supply quality of the circuit, and extend the service life of the indicator 45. Related technologies propose a power indicator circuit 40. In these technologies, a transformer is used to step down the high voltage input to the power input terminal 10 to power the indicator device 45. In existing technologies, the energy storage filter capacitor 46 is coupled to the transformer. The transformer's voltage reduction circuit has greater ripple and a longer energy replenishment cycle, requiring the energy storage filter capacitor 46 to provide greater energy loss. Therefore, in existing technologies, the energy storage filter capacitor 46 needs to store a large amount of energy when charging, and discharges slowly when power is off, resulting in a delay in the brightness change of the LED. For example, when the power supply circuit 100 is disconnected, the LED does not immediately turn off but turns off after a certain delay, which can easily lead users to misjudge the state of the power supply circuit 100. In this embodiment, a voltage regulator circuit 43 is used instead of a transformer to step down the voltage to power the indicator device 45. This reduces the amount of energy stored in the energy storage filter capacitor 46, accelerates the energy storage and discharge speed of the energy storage filter capacitor 46, and thus improves the problem of delayed brightness change of the LED.

[0045] In some embodiments, the voltage regulator circuit 43 includes: a Zener diode 431; a transistor 432, the input terminal of which is coupled to an overvoltage protection circuit 20, the output terminal of which is coupled to an indicator device 45, the control terminal of which is coupled to the cathode of the Zener diode 431, the anode of which is grounded, and a voltage regulator resistor 433, one end of which is coupled to the overvoltage protection circuit 20, and the other end of which is coupled between the control terminal and the cathode of the Zener diode 431.

[0046] In this embodiment, a voltage regulator circuit 43, consisting of a Zener diode 431, a transistor 432, and a Zener resistor 433, reduces the voltage to a reasonable range to power the indicator device 45. The Zener resistor 433 is coupled to the overvoltage protection circuit 20 and acts as a current limiter. The anode of the Zener diode 431 is grounded, and the cathode is connected to the Zener resistor 433. After the power input is current-limited by the Zener resistor 433, the Zener diode 431 provides a reference voltage through its reverse breakdown characteristic. The control terminal of the transistor 432 is coupled to the cathode of the Zener diode 431. The reference voltage is applied to the control terminal of the transistor 432, causing the transistor 432 to output a stable voltage value after the voltage drop to power the indicator device 45. In summary, the transistor 432 stabilizes the voltage value after the voltage drop, and its output terminal outputs a stable voltage to drive the indicator device 45. Alternatively, the transistor 432 can be an NPN type transistor or a PNP type transistor. The 433 voltage regulator resistor can be either a carbon film resistor or a metal film resistor. The resistance value of the voltage regulator resistor is selected according to the circuit's operating current.

[0047] In this embodiment, a voltage regulator circuit 43 is formed by a Zener diode 431, a transistor 432, and a Zener resistor 433. In some other embodiments, the function of the voltage regulator circuit 43 can also be achieved by a standard NPN regulator, a low-dropout regulator, or the like.

[0048] In some embodiments, the power indicator circuit 40 further includes a rectifier circuit 41, and the voltage regulator circuit 43 is coupled to the overvoltage protection circuit 20 through the rectifier circuit 41.

[0049] The rectifier circuit 41 converts the AC power input at the power input terminal 10 into DC power. The rectifier circuit 41 can be constructed using a diode bridge or a single diode combined with capacitor filtering to achieve the rectification function. In this embodiment, the rectifier circuit 41 is a half-wave rectifier circuit 41, which includes a half-wave rectifier diode 411. The anode of the half-wave rectifier diode 411 is coupled to an overvoltage protection circuit 20, and the cathode of the half-wave rectifier diode 411 is coupled to a voltage regulator circuit 43. The half-wave rectifier diode 411 is an electronic component that converts AC power into pulsating DC power through its unidirectional conductivity. In some other embodiments, the rectifier circuit 41 can also be a full-wave rectifier circuit 41. For example, the rectifier circuit 41 can also use a bridge circuit composed of four diodes for rectification. Additionally, the rectifier circuit 41 can also be a synchronous rectifier circuit 41. The type of rectifier circuit 41 is not specifically limited. In some embodiments, the power indicator circuit 40 further includes a current limiting circuit 42, and the voltage regulator circuit 43 is coupled to the overvoltage protection circuit 20 through the current limiting circuit 42.

[0050] The current limiting circuit 42 prevents excessive current. In this embodiment, the current limiting circuit 42 includes two resistors (not shown) connected in series. In some other embodiments, the current limiting circuit 42 can be composed of any number of resistors connected in series and parallel. In some other embodiments, the current limiting circuit 42 can also be a buck converter circuit, an inductor current limiting circuit 42, etc., and the specific type of the current limiting circuit 42 is not limited. In still other embodiments, a combination of resistors and transistors can be used to achieve the purpose of current limiting, for example, a current limiting resistor is connected in series at the output of the voltage regulator circuit 43 and a control transistor is connected in parallel. This embodiment provides dual protection for the power supply circuit 100 against both current and voltage by simultaneously setting up the overvoltage protection circuit 20 and the current limiting circuit 42.

[0051] In some embodiments, the power indicator circuit 40 further includes a high-frequency filter circuit 44, which is connected in parallel with the voltage regulator circuit 43.

[0052] In this embodiment, the high-frequency filter circuit 44 includes a capacitor (not shown). Filtering through the capacitor removes high-frequency signals and provides circuit protection. Specifically, the high-frequency filter circuit 44 can be an RC circuit (resistor-capacitor circuit), an LCπ-type filter circuit (inductor-capacitor π-type filter circuit), etc. In some embodiments, the LCπ-type filter circuit can be composed of a capacitor and an inductor. Furthermore, the function of the high-frequency filter circuit 44 can also be achieved by using electronic components such as ceramic filters. In other embodiments, a multilayer ceramic capacitor combined with a common-mode choke can be used to form a filter module. Alternatively, an integrated filter chip can be used to replace the high-frequency filter circuit 44 to reduce the number of components.

[0053] In some embodiments, the power supply circuit 100 further includes a protection circuit, and the overvoltage protection circuit 20 is coupled to the power input terminal 10 through the protection circuit.

[0054] In this embodiment, the overvoltage protection circuit 20 is a fuse 50. Setting a fuse 50 can effectively prevent the overvoltage protection circuit 20 from short-circuiting under multiple surge impacts and continuous overvoltage, thus avoiding the problem of safety accidents.

[0055] In some embodiments, the energy storage filter capacitor 46 is connected in parallel to the output terminal of the voltage regulator circuit 43. Specifically, the energy storage filter capacitor 46 can be an electrolytic capacitor or a ceramic capacitor. In some other embodiments, the energy storage filter capacitor 46 can be replaced by an integrated voltage regulator chip, which can also store energy and absorb transient voltage fluctuations in the circuit. Furthermore, the voltage regulator circuit 43 can be constructed using discrete components, or an integrated voltage regulator chip can be used instead of the voltage regulator circuit 43. Additionally, the capacitance parameter of the energy storage filter capacitor 46 can be selected according to the actual operating frequency. For example, the size of the energy storage filter capacitor can be from 100 farads to 470 farads, and specifically, the energy storage filter capacitor 46 can be 100 farads, 150 farads, 250 farads, 300 farads, 470 farads, etc. The connection between the voltage regulator circuit 43 and the indicator device 45 can be direct power supply. Alternatively, in some embodiments, the indicator device 45 can be powered by adjusting the current through a current-limiting resistor (not shown).

[0056] Unlike existing technologies, this application provides a power supply circuit 100. This power supply circuit 100 couples an overvoltage protection circuit 20 between the power input terminal 10 and the power indicator circuit 40. The overvoltage protection circuit 20 can suppress transient overvoltage surges and clamp the high voltage of a lightning strike to a safe value during a lightning strike, reducing the risk of damage to the power indicator circuit 40. The overvoltage protection circuit 20 can also quickly release charge, reducing electrostatic discharge damage. Furthermore, by using a voltage regulator circuit 43 instead of a transformer to step down the voltage for powering the indicator device 45, the amount of charge stored in the energy storage filter capacitor 46 can be reduced, accelerating the storage and discharge speed of the energy storage filter capacitor 46, thereby improving the problem of delayed brightness changes in the light-emitting diode.

[0057] Correspondingly, this application also proposes an electronic device that includes the power supply circuit 100 of any of the above embodiments. Specifically, the electronic device can be any reasonable type of electronic device such as a charger, power strip, home audio-visual equipment, or small household appliances.

[0058] Finally, in a specific application scenario, existing power supply circuits lack lightning and electrostatic protection, making the power indicator circuit susceptible to damage from lightning strikes and electrostatic discharge. The power supply circuit 100 of this application includes an overvoltage protection circuit 20 and a power indicator circuit 40. One end of the overvoltage protection circuit 20 is coupled to the power input terminal 10, and the other end is coupled to the power output terminal 30; the power indicator circuit 40 is coupled to the overvoltage protection circuit 20. The overvoltage protection circuit 20 includes a varistor 21, which is coupled to the power input terminal 10. The power indicator circuit 40 also includes an indicator device 45, a voltage regulator circuit 43, and an energy storage filter capacitor 46. One end of the voltage regulator circuit 43 is coupled to the overvoltage protection circuit 20, and the other end is coupled to the indicator device 45; the energy storage filter capacitor 46 is connected in parallel with the voltage regulator circuit 43. The voltage regulator circuit 43 includes: a Zener diode 431; a transistor 432, the input terminal of which is coupled to an overvoltage protection circuit 20, the output terminal of which is coupled to an indicator 45, the control terminal of which is coupled to the cathode of the Zener diode 431, the anode of which is grounded; and a voltage regulator resistor 433, one end of which is coupled to the overvoltage protection circuit 20, and the other end of which is coupled between the control terminal and the cathode of the Zener diode 431. The power indicator circuit 40 also includes a rectifier circuit 41, through which the voltage regulator circuit 43 is coupled to the overvoltage protection circuit 20. The power indicator circuit 40 also includes a current limiting circuit 42, through which the voltage regulator circuit 43 is coupled to the overvoltage protection circuit 20. The power indicator circuit 40 further includes a high-frequency filter circuit 44, which is connected in parallel with the voltage regulator circuit 43. The power supply circuit 100 also includes a protection circuit, and the overvoltage protection circuit 20 is coupled to the power input terminal 10 through the protection circuit.

[0059] The above are merely embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A power supply circuit, characterized in that, The power supply circuit includes: An overvoltage protection circuit, wherein one end of the overvoltage protection circuit is coupled to the power input terminal and the other end is coupled to the power output terminal; A power indicator circuit is coupled to the overvoltage protection circuit. The power indicator circuit includes an indicator device and a voltage regulator circuit. One end of the voltage regulator circuit is coupled to the overvoltage protection circuit, and the other end of the voltage regulator circuit is coupled to the indicator device.

2. The power supply circuit according to claim 1, characterized in that, The overvoltage protection circuit includes a varistor, which is coupled to the power input terminal.

3. The power supply circuit according to claim 1, characterized in that, The power indicator circuit also includes: An energy storage filter capacitor is provided, which is connected in parallel with the voltage regulator circuit.

4. The power supply circuit according to claim 3, characterized in that, The voltage regulator circuit includes: Zener diode; A transistor, wherein the input terminal of the transistor is coupled to the overvoltage protection circuit, the output terminal of the transistor is coupled to the indicator device, the control terminal of the transistor is coupled to the cathode of the Zener diode, and the anode of the Zener diode is grounded. A voltage regulator resistor, one end of which is coupled to the overvoltage protection circuit, and the other end of which is coupled between the control terminal and the cathode of the Zener diode.

5. The power supply circuit according to claim 3, characterized in that, The power indicator circuit also includes: A rectifier circuit, wherein the voltage regulator circuit is coupled to the overvoltage protection circuit through the rectifier circuit.

6. The power supply circuit according to claim 5, characterized in that, The rectifier circuit includes a half-wave rectifier diode, the anode of which is coupled to the overvoltage protection circuit, and the cathode of which is coupled to the voltage regulator circuit.

7. The power supply circuit according to claim 3, characterized in that, The power indicator circuit also includes: A current limiting circuit is provided, and the voltage regulating circuit is coupled to the overvoltage protection circuit through the current limiting circuit.

8. The power supply circuit according to claim 3, characterized in that, The power indicator circuit also includes: A high-frequency filter circuit is provided, which is connected in parallel with the voltage regulator circuit.

9. The power supply circuit according to claim 1, characterized in that, The power supply circuit also includes: The overvoltage protection circuit is coupled to the power input terminal.

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

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