Power supply positive and negative connection circuit, power supply device and electronic equipment
By using a reverse connection circuit composed of PMOS and NMOS transistors in the power supply reverse connection circuit, the problems of large voltage drop and high loss in the power supply reverse connection protection circuit are solved, achieving low voltage drop and low loss power output and improving battery life.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHENZHEN KAADAS INTELLIGENT TECH CO LTD
- Filing Date
- 2025-08-11
- Publication Date
- 2026-07-21
AI Technical Summary
Existing reverse connection protection circuits suffer from large voltage drop and high losses, which can easily damage electronic products, especially when the battery is connected in either direction.
The power supply adopts a positive and negative connection circuit design, using positive and negative connection circuits composed of PMOS and NMOS transistors. The conduction state of the switching transistor is controlled by connecting the power interface with different polarities. Combined with surge protection circuit, the normal power output is ensured.
It achieves low voltage drop and low loss power output, improves battery life, and reduces the risk of circuit damage, especially with a voltage drop lower than traditional rectifier bridge solutions under low voltage conditions.
Smart Images
Figure CN224538052U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of electronic circuits, and in particular to a power supply positive and negative connection circuit, a power supply device, and an electronic device. Background Technology
[0002] With the increasing number of mobile electronic products such as mobile phones, power banks, electric shavers, and battery cameras, users are particularly concerned about the battery life of battery-powered products. Engineers need to consider multiple dimensions in circuit design and component parameter selection, such as power loss, conversion efficiency, and reverse connection protection. During battery use, it is necessary to distinguish between positive and negative terminals. Incorrect connection of positive and negative terminals can easily damage electronic products, which requires the electronic products to be designed with reverse connection protection.
[0003] Conventional reverse connection protection technology uses a rectifier bridge at the power input, so the circuit board will not be damaged if the battery is connected in either direction. However, this circuit has many drawbacks. The rectifier bridge is composed of four diodes. Because of the voltage drop of the diodes, if the voltage drops below the minimum input requirement of the system, it will cause the system to restart. In addition, the diodes generate a lot of heat and will consume battery power themselves, resulting in losses. Utility Model Content
[0004] In view of the shortcomings of the prior art, the purpose of this utility model is to provide a power supply positive and negative connection circuit, a power supply device and an electronic device to solve the problems of large voltage drop and high loss in the anti-reverse connection circuit.
[0005] The technical solution of this utility model is as follows:
[0006] A power supply reversal circuit, comprising:
[0007] A power interface, including a first end and a second end, is used to connect to a power source.
[0008] System power supply terminal, used to connect to the system power supply;
[0009] A positive connection circuit is provided, which is connected to the power interface. The output terminal of the positive connection circuit is used to connect to the system power terminal. When the first terminal of the power interface is connected to the positive terminal of the power supply, the positive connection circuit is used to output power to the system power terminal and connect the second terminal of the power interface to ground.
[0010] A reverse connection circuit is provided, which is connected to the power interface. The output terminal of the reverse connection circuit is used to connect to the system power terminal. When the second terminal of the power interface is connected to the positive power terminal, the reverse connection circuit outputs power to the system power terminal and connects the first terminal of the power interface to ground.
[0011] Optionally, the positive connection circuit includes a first resistor, a first switch, a second switch, a third switch, and a fourth switch, and the reverse connection circuit includes a second resistor, a fifth switch, a sixth switch, a seventh switch, and an eighth switch.
[0012] The input terminal of the first switch, the first terminal of the second resistor, and the output terminal of the seventh switch are connected to the first terminal of the power interface. The controlled terminals of the first, second, seventh, and eighth switches are interconnected with the first terminal of the first resistor. The output terminal of the first switch is connected to the input terminal of the second switch. The output terminals of the second and fifth switches are connected to the system power supply terminal. The controlled terminals of the third, fourth, fifth, and sixth switches are interconnected with the second terminal of the second resistor. The input terminal of the fifth switch is connected to the output terminal of the sixth switch. The input terminal of the sixth switch, the second terminal of the first resistor, and the output terminal of the fourth switch are connected to the second terminal of the power interface. The input terminal of the third switch is connected to the input terminal of the eighth switch. The output terminal of the third switch is connected to the input terminal of the fourth switch. The output terminal of the eighth switch is connected to the input terminal of the seventh switch.
[0013] Optionally, the first, second, fifth, and sixth switching transistors are PMOS transistors, and the third, fourth, seventh, and eighth switching transistors are NMOS transistors.
[0014] Optionally, it also includes:
[0015] A surge protection circuit is provided, which is connected in parallel between the power interface and the positive connection circuit and the reverse connection circuit. The surge protection circuit is used to divert surge energy to ground when the power supply connected to the power interface is overvoltage.
[0016] Optionally, the surge protection circuit includes a first surge protection device, a second surge protection device, and a third surge protection device. The first end of the first surge protection device and the first end of the second surge protection device are connected to the first end of the power interface. The second end of the first surge protection device is grounded. The first end of the third surge protection device and the second end of the second surge protection device are connected to the second end of the power interface. The second end of the second surge protection device is grounded.
[0017] Optionally, the first surge protection device, the second surge protection device, and the third surge protection device are transient voltage suppression diodes.
[0018] This utility model also proposes a power supply device, including a system power supply and a power supply positive and negative connection circuit as described above, wherein the output terminal of the power supply positive and negative connection circuit is connected to the input terminal of the system power supply.
[0019] This invention also proposes an electronic device, including the power supply device described above.
[0020] This utility model's technical solution comprises a power supply positive and negative connection circuit using a power interface, a system power terminal, a positive connection circuit, and a reverse connection circuit. The power interface connects to the positive and negative terminals of the power supply via a first terminal and a second terminal. The system power terminal connects to the system power supply. When the positive terminal of the power supply is connected to the first terminal of the power interface, the positive connection circuit outputs power to the system power terminal and connects the second terminal of the power interface to ground. Similarly, when the positive terminal of the power supply is connected to the second terminal of the power supply, the reverse connection circuit outputs power to the system power terminal and connects the first terminal of the power interface to ground. Thus, this power supply positive and negative connection circuit ensures the normal operation of subsequent circuits by outputting power through the positive connection circuit when the power supply and the power interface are connected correctly, and through the reverse connection circuit when the power supply and the power interface are connected incorrectly. Attached Figure Description
[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.
[0022] Figure 1 This is a functional module schematic diagram of an embodiment of the power supply positive and negative connection circuit of this utility model.
[0023] Figure 2 This is a schematic diagram of the circuit structure of one embodiment of the power supply positive and negative connection circuit of this utility model.
[0024] Explanation of reference numerals in the attached diagram: 10, positive connection circuit; 20, reverse connection circuit; J1, power interface; VSYS, system power supply terminal; Q1, first switching transistor; Q2, second switching transistor; Q3, third switching transistor; Q4, fourth switching transistor; Q5, fifth switching transistor; Q6, sixth switching transistor; Q7, seventh switching transistor; Q8, eighth switching transistor; R1, first resistor; R2, second resistor; TVS1, first surge protector; TVS2, second surge protector; TVS3, third surge protector. Detailed Implementation
[0025] To make the objectives, technical solutions, and effects of this utility model clearer and more explicit, the present utility model will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.
[0026] In the implementation methods and claims, unless otherwise specified in the text, the terms "a," "an," "the," and "the" may also include plural forms. If the embodiments of this utility model involve descriptions of "first," "second," etc., such descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features.
[0027] It should be further understood that the term "comprising" as used in this specification means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. It should be understood that when an element is referred to as "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or there may be intermediate elements present. Furthermore, "connected" or "coupled" as used herein can include wireless connections or wireless coupling. The term "and / or" as used herein includes all or any unit and all combinations of one or more associated listed items.
[0028] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless specifically defined as herein.
[0029] Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.
[0030] With the increasing number of mobile electronic products such as mobile phones, power banks, electric shavers, and battery cameras, users are particularly concerned about the battery life of battery-powered products. Engineers need to consider multiple dimensions in circuit design and component parameter selection, such as power loss, conversion efficiency, and reverse connection protection. During battery use, it is necessary to distinguish between positive and negative terminals. Incorrect connection of positive and negative terminals can easily damage electronic products, which requires the electronic products to be designed with reverse connection protection.
[0031] Conventional reverse connection protection technology uses a rectifier bridge at the power input, so the circuit board will not be damaged if the battery is connected in either direction. However, this circuit has many drawbacks. The rectifier bridge is composed of four diodes. Because of the voltage drop of the diodes, if the voltage drops below the minimum input requirement of the system, it will cause the system to restart. In addition, the diodes generate a lot of heat and will consume battery power themselves, resulting in losses.
[0032] To solve the above problems, this utility model proposes a power supply positive and negative connection circuit 20.
[0033] Reference Figure 1 In one embodiment, the power supply positive and negative circuit 20 includes:
[0034] The power interface J1 includes a first end and a second end, and the power interface J1 is used to connect to a power source.
[0035] The system power supply terminal VSYS is used to connect to the system power supply.
[0036] Positive connection circuit 10, which is connected to the power interface J1, is used to connect the output terminal of the positive connection circuit 10 to the system power terminal VSYS. When the first terminal of the power interface J1 is connected to the positive terminal of the power supply, the positive connection circuit 10 is used to output power to the system power terminal VSYS and connect the second terminal of the power interface J1 to ground.
[0037] A reverse connection circuit 20 is connected to the power interface J1. The output terminal of the reverse connection circuit 20 is used to connect to the system power terminal VSYS. When the second terminal of the power interface J1 is connected to the positive power supply, the reverse connection circuit 20 outputs power to the system power terminal VSYS and connects the first terminal of the power interface J1 to ground.
[0038] In this embodiment, the power source connected to the power interface J1 can be a battery output or other power supply device. The first and second terminals of the power interface J1 are used to connect the positive and negative terminals of the power supply. The system power terminal VSYS is connected to the system's main power supply or to the downstream load. That is, the power reversal circuit 20 in this embodiment connects to the power supply through the power interface J1 and then outputs the power to the system power supply through the system power terminal VSYS. It can be understood that this embodiment sets up a positive connection circuit 10 and a reverse connection circuit 20. The description is based on the case where the first terminal of the power interface J1 is connected to the positive terminal of the power supply. In this case, the positive connection circuit 10 outputs the power to the system power terminal, and then grounds the second terminal of the power interface J1, thus forming a current loop. Conversely, if the second terminal of the power interface J1 is connected to the positive terminal of the power supply, it is a reverse connection. In this case, the reverse connection circuit 20 outputs the power to the system power terminal, and then grounds the first terminal of the power interface J1, thus forming a current loop. In this embodiment, the positive connection circuit 10 and the reverse connection circuit 20 can be composed of switching devices, and the conduction or cutoff of the switching devices in the positive connection circuit 10 and the reverse connection circuit 20 can be controlled by the connection state of the positive and negative terminals of the power supply, thereby controlling the conduction of the circuit and enabling the power supply to be output normally to the system power supply terminal VSYS.
[0039] This utility model's technical solution uses a power interface J1, a system power terminal VSYS, a positive connection circuit 10, and a reverse connection circuit 20 to form a power supply positive and negative connection circuit 20. The power interface J1 is connected to the positive and negative terminals of the power supply via its first and second terminals. The system power terminal VSYS is used to connect to the system power supply. When the first terminal of the power interface J1 is connected to the positive terminal of the power supply, the positive connection circuit 10 outputs power to the system power terminal VSYS and connects the second terminal of the power interface J1 to ground. When the second terminal of the power interface J1 is connected to the positive terminal of the power supply, the reverse connection circuit 20 outputs power to the system power terminal VSYS and connects the first terminal of the power interface J1 to ground. Thus, this power supply positive and negative connection circuit 20 outputs power through the positive connection circuit 10 when the power supply and the power interface J1 are positively connected, and through the reverse connection circuit 20 when the power supply and the power interface J1 are reversely connected, ensuring the normal operation of subsequent circuits.
[0040] Reference Figure 2 In one embodiment, the positive connection circuit 10 includes a first resistor R1, a first switch Q1, a second switch Q2, a third switch Q3 and a fourth switch Q4, and the reverse connection circuit 20 includes a second resistor R2, a fifth switch Q5, a sixth switch Q6, a seventh switch Q7 and an eighth switch Q8.
[0041] The input terminal of the first switch Q1, the first terminal of the second resistor R2, and the output terminal of the seventh switch Q7 are connected to the first terminal of the power interface J1. The controlled terminals of the first switch Q1, the second switch Q2, the seventh switch Q7, and the eighth switch Q8 are interconnected with the first terminal of the first resistor R1. The output terminal of the first switch Q1 is connected to the input terminal of the second switch Q2. The output terminals of the second switch Q2 and the fifth switch Q5 are connected to the system power terminal VSYS. The controlled terminals of the third switch Q3 and the fourth switch Q4 are connected to the first terminal of the power interface J1. The controlled terminal, the controlled terminal of the fifth switch Q5, and the controlled terminal of the sixth switch Q6 are interconnected with the second terminal of the second resistor R2. The input terminal of the fifth switch Q5 is connected to the output terminal of the sixth switch Q6. The input terminal of the sixth switch Q6, the second terminal of the first resistor R1, and the output terminal of the fourth switch Q4 are connected to the second terminal of the power interface J1. The input terminal of the third switch Q3 is connected to the input terminal of the eighth switch Q8. The output terminal of the third switch Q3 is connected to the input terminal of the fourth switch Q4. The output terminal of the eighth switch Q8 is connected to the input terminal of the seventh switch Q7.
[0042] The first switch Q1, the second switch Q2, the fifth switch Q5 and the sixth switch Q6 are PMOS transistors, and the third switch Q3, the fourth switch Q4, the seventh switch Q7 and the eighth switch Q8 are NMOS transistors.
[0043] In this embodiment, when the first terminal of the positive connection circuit 10 is connected to the positive terminal of the power supply and the second terminal is connected to the negative terminal of the power supply, it represents a positive connection of the power supply. Since the gates of the first switch Q1 and the second switch Q2 are connected to the first resistor R1 and grounded through the first resistor R1, and since the first switch Q1 and the second switch Q2 are PMOS transistors in this embodiment, the first switch Q1 and the second switch Q2 are in the on state. The path of the positive current is from the first switch Q1 to the second switch Q2 to the system power supply terminal VSYS and enter the system or subsequent circuit. After passing through the load, it finally loops back to the input terminal of the third switch Q3 through the system ground. Since the gates of the third switch Q3 and the fourth switch Q4 are connected to the second resistor R2, the second resistor R2 is connected to the positive terminal of the power supply, and the third switch Q3 is an NMOS transistor, the third switch Q3 and the fourth switch Q4 are on. The system ground finally returns to the second terminal of the power interface J1 through the third switch Q3 and the fourth switch Q4, forming a current loop.
[0044] When the second terminal of the positive connection circuit 10 is connected to the positive terminal of the power supply and the first terminal is connected to the negative terminal of the power supply, it represents a reverse connection of the power supply. Since the gates of the fifth switch Q5 and the sixth switch Q6 are connected to the second resistor R2, and the current flows to ground through the second resistor R2, and since the fifth switch Q5 and the sixth switch Q6 are PMOS transistors, the fifth switch Q5 and the sixth switch Q6 are conducting at this time. The path of the positive current is from the sixth switch Q6 to the fifth switch Q5 to the system power supply terminal VSYS, entering the system or subsequent circuits. After passing through the load, it finally loops back to the input terminal of the eighth switch Q8 from the system ground. Since the gates of the seventh switch Q7 and the eighth switch Q8 are connected to the first resistor R1, and the current flows to the positive terminal of the power supply through the first resistor R1, and since the seventh switch Q7 and the eighth switch Q8 are NMOS transistors, the seventh switch Q7 and the eighth switch Q8 are conducting. The system ground finally returns to the first terminal of the power interface J1 through the seventh switch Q7 and the eighth switch Q8, forming a current loop.
[0045] It is understandable that this embodiment utilizes the low on-voltage characteristic of MOSFETs. In the circuit design, four NMOS transistors, four PMOS transistors, and two resistors are used to form the power supply reversal circuit 20. The power supply circuit 20 meets the power circuit requirements by controlling the on-state of different MOSFETs through the positive and negative terminals of the battery. This embodiment of the power supply reversal circuit 20 solves the drawbacks of the rectifier bridge and achieves the advantages of low voltage drop, low internal resistance, high current, and low damage. In particular, the ultra-low voltage drop technology improves the battery life. For example, if a 9V battery passes through a traditional diode solution to the system terminal, it will only have 7.6V, and the line will consume 1.4V. However, the power supply reversal circuit 20 in this embodiment only generates a voltage drop of 0.1 to 0.4V in the circuit. The internal resistance of a conventional MOSFET is 50mΩ, and the voltage drop V = 4 * 50 * 2A = 0.4V (where 4 represents the number of MOSFETs and the current in the circuit I = 2A), which is much smaller than the voltage drop generated by the rectifier bridge circuit. Therefore, the power supply reversal circuit 20 in this embodiment has a small voltage drop and low loss.
[0046] It should be noted that in this embodiment, the controlled terminals of the switching transistors are all gates of MOS transistors. The input terminals of the first switch Q1 and the sixth switch Q6 are the drains of PMOS transistors, and the output terminals of the first switch Q1 and the sixth switch Q6 are the sources of PMOS transistors. The input terminals of the second switch Q2 and the fifth switch Q5 are the sources of PMOS transistors, and the output terminals of the second switch Q2 and the fifth switch Q5 are the drains of PMOS transistors. The input terminals of the third switch Q3 and the eighth switch Q8 are the sources of NMOS transistors, and the output terminals of the third switch Q3 and the eighth switch Q8 are the drains of NMOS transistors. The input terminals of the fourth switch Q4 and the seventh switch Q7 are the drains of NMOS transistors, and the output terminals of the fourth switch Q4 and the seventh switch Q7 are the sources of NMOS transistors. Furthermore, the MOS transistors used in this embodiment are enhancement-mode MOS transistors.
[0047] In one embodiment, the power supply positive and negative circuit 20 further includes:
[0048] A surge protection circuit is provided, which is connected in parallel between the power interface J1 and the positive connection circuit 10 and the reverse connection circuit 20. The surge protection circuit is used to divert surge energy to ground when the power supply connected to the power interface J1 is overvoltage.
[0049] In this embodiment, a surge protection circuit is installed between the power interface J1 and the positive connection circuit 10 and the reverse connection circuit 20, which can protect the power positive and reverse connection circuits 20 from damage caused by power surge voltage. The surge protection circuit can quickly cut off or limit the current when the voltage of the power interface J1 exceeds a set threshold, thereby protecting the downstream circuits. The specific threshold can be set according to the actual situation and user needs.
[0050] Furthermore, referring to Figure 2 In one embodiment, the surge protection circuit includes a first surge protection device TVS1, a second surge protection device TVS2, and a third surge protection device TVS3. The first end of the first surge protection device TVS1 and the first end of the second surge protection device TVS2 are connected to the first end of the power interface J1. The second end of the first surge protection device TVS1 is grounded. The first end of the third surge protection device TVS3 and the second end of the second surge protection device TVS2 are connected to the second end of the power interface J1. The second end of the second surge protection device TVS2 is grounded.
[0051] The first surge protection device TVS1, the second surge protection device TVS2, and the third surge protection device TVS3 are transient voltage suppression diodes.
[0052] In this embodiment, surge protection devices are connected to both the first and second ends of the power interface J1, providing surge protection in both positive and negative power connections. Furthermore, in this embodiment, the first surge protection device TVS1, the second surge protection device TVS2, and the third surge protection device TVS3 can be transient voltage suppressor diodes (TVS diodes). TVS diodes can respond to transient voltages within nanoseconds, rapidly suppressing surges and protecting downstream circuits. Moreover, the clamping voltage of TVS diodes is typically low, effectively limiting voltage peaks and reducing damage to sensitive components. Alternatively, the first surge protection device TVS1, the second surge protection device TVS2, and the third surge protection device TVS3 can also be varistors, gas discharge tubes, or other similar devices.
[0053] This utility model also proposes a power supply device.
[0054] In one embodiment, the power supply device includes a system power supply and a power reversal circuit 20 as described above, wherein the output terminal of the power reversal circuit 20 is connected to the input terminal of the system power supply. It is understood that since the power reversal circuit 20 described above is used in the power supply device of this utility model, the embodiments of the power supply device of this utility model include all the technical solutions of all embodiments of the power reversal circuit 20, and the achieved technical effects are exactly the same, and will not be repeated here.
[0055] This utility model also proposes an electronic device.
[0056] In one embodiment, the electronic device includes the power supply device as described above. It is understood that since the electronic device of this invention uses the aforementioned power supply device, the embodiments of the electronic device of this invention include all the technical solutions of all embodiments of the aforementioned power supply device, and the achieved technical effects are completely identical, and will not be repeated here.
[0057] It should be understood that the application of this utility model is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.
Claims
1. A power supply positive and negative connection circuit, characterized in that, include: A power interface, including a first end and a second end, is used to connect to a power source. System power supply terminal, used to connect to the system power supply; A positive connection circuit is provided, which is connected to the power interface. The output terminal of the positive connection circuit is used to connect to the system power terminal. When the first terminal of the power interface is connected to the positive terminal of the power supply, the positive connection circuit is used to output power to the system power terminal and connect the second terminal of the power interface to ground. A reverse connection circuit is provided, which is connected to the power interface. The output terminal of the reverse connection circuit is used to connect to the system power terminal. When the second terminal of the power interface is connected to the positive power terminal, the reverse connection circuit outputs power to the system power terminal and connects the first terminal of the power interface to ground.
2. The power supply positive and negative connection circuit as described in claim 1, characterized in that, The positive connection circuit includes a first resistor, a first switch, a second switch, a third switch, and a fourth switch; the reverse connection circuit includes a second resistor, a fifth switch, a sixth switch, a seventh switch, and an eighth switch. The input terminal of the first switch, the first terminal of the second resistor, and the output terminal of the seventh switch are connected to the first terminal of the power interface. The controlled terminals of the first, second, seventh, and eighth switches are interconnected with the first terminal of the first resistor. The output terminal of the first switch is connected to the input terminal of the second switch. The output terminals of the second and fifth switches are connected to the system power supply terminal. The controlled terminals of the third, fourth, fifth, and sixth switches are interconnected with the second terminal of the second resistor. The input terminal of the fifth switch is connected to the output terminal of the sixth switch. The input terminal of the sixth switch, the second terminal of the first resistor, and the output terminal of the fourth switch are connected to the second terminal of the power interface. The input terminal of the third switch is connected to the input terminal of the eighth switch. The output terminal of the third switch is connected to the input terminal of the fourth switch. The output terminal of the eighth switch is connected to the input terminal of the seventh switch.
3. The power supply positive and negative connection circuit as described in claim 2, characterized in that, The first, second, fifth, and sixth switching transistors are PMOS transistors, while the third, fourth, seventh, and eighth switching transistors are NMOS transistors.
4. The power supply positive and negative connection circuit as described in claim 1, characterized in that, Also includes: A surge protection circuit is provided, which is connected in parallel between the power interface and the positive connection circuit and the reverse connection circuit. The surge protection circuit is used to divert surge energy to ground when the power supply connected to the power interface is overvoltage.
5. The power supply positive and negative connection circuit as described in claim 4, characterized in that, The surge protection circuit includes a first surge protection device, a second surge protection device, and a third surge protection device. The first end of the first surge protection device and the first end of the second surge protection device are connected to the first end of the power interface. The second end of the first surge protection device is grounded. The first end of the third surge protection device and the second end of the second surge protection device are connected to the second end of the power interface. The second end of the second surge protection device is grounded.
6. The power supply positive and negative connection circuit as described in claim 5, characterized in that, The first surge protection device, the second surge protection device, and the third surge protection device are transient voltage suppression diodes.
7. A power supply device, characterized in that, It includes a system power supply and a power supply reversing circuit as described in any one of claims 1-6, wherein the output terminal of the power supply reversing circuit is connected to the input terminal of the system power supply.
8. An electronic device, characterized in that, Includes the power supply device as described in claim 7.