Dual-power switching circuit capable of preventing reverse connection and electronic equipment thereof

Abstract

The utility model provides a dual power supply switching circuit capable of preventing reverse connection and an electronic device thereof, relating to the technical field of dual power supply, the circuit realizes the selection of power supply of an adapter and a battery through a simple electronic device, and avoids the complexity and risk of traditional judgment depending on a software program. According to the circuit, the reverse connection prevention function is ingeniously achieved by means of the high-level cut-off and low-level conduction characteristics of a PMOS tube and the characteristic that reverse current of a diode cannot pass through. When the adapter is correctly accessed, the circuit preferentially selects the adapter to supply power; and when the adapter is not connected and the battery is correctly connected, the circuit is automatically switched to be powered by the battery. In addition, when the adapter or the battery is reversely connected, the circuit can be effectively prevented from being short-circuited and damaged. The circuit is simple in structure, low in power consumption and rapid in response, can realize automatic switching among different power supplies, and has relatively high practicability and reliability.

Description

TECHNICAL FIELD

[0001] The utility model relates to dual power supply technology field, concretely relates to a dual power supply switching circuit and electronic equipment of preventing reverse connection. BACKGROUND

[0002] At present, in the existing power switching circuit, there are usually some defects and deficiencies. On the one hand, many dual power supply switching circuits lack the function of preventing reverse connection, which may cause short circuit or damage of the circuit when the power polarity is reversed, thereby affecting the normal operation and service life of the equipment. On the other hand, although some circuits have the function of preventing reverse connection, they do not support dual power switching, and cannot flexibly switch between different power sources such as adapters and batteries, which limits the adaptability and flexibility of the equipment in different use scenarios. In addition, when realizing the function of selecting different power sources, the traditional power switching circuit often relies on complex software programs to judge and control the power path, which not only increases the workload of software development, but also has the risk of program bugs, which may cause inaccurate or delayed power switching, affecting the stability and reliability of the equipment. Therefore, the existing technology has obvious deficiencies in the combination of dual power switching and reverse connection prevention function, and there is an urgent need for a circuit scheme that can simultaneously realize reverse connection prevention and dual power switching to meet the higher requirements of modern electronic equipment for power management.

[0003] In view of this, the present application is proposed. UTILITY MODEL CONTENT

[0004] The utility model discloses a dual power supply switching circuit and electronic equipment of preventing reverse connection, aims at solving the deficiency that the existing circuit is combined in dual power switching and reverse connection prevention function.

[0005] The utility model discloses a dual power supply switching circuit of preventing reverse connection, it is characterized by including: adapter, battery piece, switch tube subassembly, first diode, prevent overvoltage diode subassembly and resistance, the adapter is used to be connected with external power, the positive terminal of the adapter passes through first diode and is electrically connected with the power end of external electronic equipment, the positive terminal of the adapter passes through prevent overvoltage diode subassembly and is grounded, the positive terminal of the adapter passes through resistance and is grounded, the positive terminal of battery piece passes through switch tube subassembly and is electrically connected with the power end of external electronic equipment, the positive terminal of battery piece passes through prevent overvoltage diode subassembly and is grounded;

[0006] Among them, the switch tube subassembly is configured to, when only the positive and negative poles of the battery piece are correctly connected, the switch tube subassembly is turned on, and in other cases, the switch tube subassembly is cut off.

[0007] The first diode is configured to be turned on when the positive and negative poles of the adapter are correctly connected, and the first diode is turned off in other cases.

[0008] Preferably, the anti-overvoltage diode assembly comprises a first TVS diode and a second TVS diode, one end of the first TVS diode is electrically connected to the positive pole of the battery piece, the other end of the first TVS diode is grounded, one end of the second TVS diode is electrically connected to the positive pole of the adapter, the other end of the second TVS diode is grounded, and the first TVS diode and the second TVS diode are configured to protect the circuit from overvoltage.

[0009] Preferably, the switch tube assembly comprises a first switch tube and a second switch tube, the control end of the first switch tube and the control end of the second switch tube are electrically connected to the positive pole of the adapter, the first end of the first switch tube is electrically connected to the positive pole of the battery piece, the second end of the first switch tube is electrically connected to the second end of the second switch tube, and the first end of the second switch tube is electrically connected to the power supply end of the external electronic equipment.

[0010] Preferably, the first switch tube and the second switch tube are PMOS tubes.

[0011] Preferably, the control end of the first switch tube is the gate of the PMOS tube, the first end of the first switch tube is the drain of the PMOS tube, and the second end of the first switch tube is the source of the PMOS tube.

[0012] Preferably, the control end of the second switch tube is the gate of the PMOS tube, the first end of the second switch tube is the drain of the PMOS tube, and the second end of the second switch tube is the source of the PMOS tube.

[0013] Preferably, the resistance is 100KΩ.

[0014] Preferably, the positive pole of the first diode is electrically connected to the positive pole of the adapter, and the negative pole of the first diode is electrically connected to the power supply end of the external electronic equipment.

[0015] The utility model discloses still a kind of electronic equipment, it includes equipment body, and the double power supply switching circuit of anti-reverse connection as any one described above, the double power supply switching circuit of anti-reverse connection is configured in the inside of the equipment body.

[0016] In summary, the anti-reverse connection dual power supply switching circuit combines the anti-reverse connection function with the dual power supply switching function, overcoming many shortcomings in the prior art. Specifically, the anti-reverse connection dual power supply switching circuit uses the characteristics of PMOS tubes and diodes to achieve automatic selection of adapter and battery power supply, and can preferentially select adapter power supply when the adapter and the battery are connected at the same time, and automatically switch to battery power supply when the adapter is not connected. In addition, the circuit fully considers the need for anti-reverse connection in design, and can effectively prevent circuit short circuit and damage when the adapter or battery is reverse connected, thereby improving the safety and reliability of the circuit. Compared with traditional circuits relying on software program control, the circuit has simple structure, low power consumption, and rapid response, without the need for complex software programming, reducing development and maintenance costs. Overall, the circuit provides an efficient and reliable power management solution, suitable for various electronic devices that require flexible power switching and anti-reverse connection protection, and has wide application prospects and important practical value. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a circuit schematic diagram of the anti-reverse connection dual power supply switching circuit provided by the embodiments of the present application. DETAILED DESCRIPTION

[0018] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0019] The specific embodiments of the present application will be described in detail below in conjunction with the drawings.

[0020] Please refer to Figure 1The utility model discloses a first embodiment discloses a kind of anti-reverse connection dual power supply switching circuit, it is characterized by comprising: adapter, battery piece, switch tube component, first diode D1, overvoltage protection diode component and resistance R4, the adapter is used to connect with external power supply, the positive terminal of the adapter is electrically connected with the power supply end of external electronic equipment through the first diode D1, the positive terminal of the adapter is grounded through the overvoltage protection diode component, the positive terminal of the adapter is grounded through the resistance R4, the positive terminal of the battery piece is electrically connected with the power supply end of external electronic equipment through the switch tube component, the positive terminal of the battery piece is grounded through the overvoltage protection diode component;

[0021] Wherein, the switch tube component is configured as, only when the positive and negative pole of the battery piece is correctly accessed, the switch tube component is turned on, and in other cases, the switch tube component is all cut off.

[0022] Wherein, the first diode D1 is configured as, when the positive and negative pole of the adapter is correctly accessed, the first diode is turned on, and in other cases, the first diode is all cut off.

[0023] Preferably, the size of the resistance R4 is 100KΩ.

[0024] Preferably, the positive pole of the first diode D1 is electrically connected with the positive terminal of the adapter, and the negative pole of the first diode D1 is electrically connected with the power supply end of external electronic equipment.

[0025] Specifically, in the embodiment, the circuit includes adapter, battery piece, switch tube component, first diode D1, overvoltage protection diode component and resistance R4. The adapter is used to connect with external power supply, and the positive terminal thereof is electrically connected with the power supply end of external electronic equipment through the first diode D1. The configuration of the first diode D1 enables the first diode D1 to be turned on when the positive and negative pole of the adapter is correctly accessed, thereby allowing current to flow from the adapter to the electronic equipment and achieving adapter power supply. When the polarity of the adapter is reversed, the first diode D1 is cut off, preventing reverse current flow and thereby effectively preventing circuit short circuit and damage, thereby embodying the anti-reverse connection function of the circuit. The positive terminal of the adapter is also grounded through the overvoltage protection diode component, and the overvoltage protection diode component functions to effectively clamp voltage when overvoltage occurs in the circuit, thereby protecting subsequent circuits from overvoltage damage and improving the stability and reliability of the circuit. At the same time, the positive terminal of the adapter is grounded through a 100KΩ resistance R4, and the setting of the resistance plays a role in limiting current when the adapter is reversed. The high resistance value of the resistance R4 can limit the size of the current, thereby avoiding damage to the adapter and further enhancing the anti-reverse connection protection capability of the circuit.

[0026] The positive terminal of the battery piece is electrically connected with the power terminal of the external electronic device through the switch tube assembly. The switch tube assembly is composed of two PMOS tubes. When the positive and negative terminals of the battery piece are correctly connected and the adapter is not connected, the switch tube assembly is turned on, allowing the battery current to flow to the electronic device, realizing battery power supply. When the adapter is connected or the battery piece is reversed, the switch tube assembly is turned off, preventing reverse current flow or battery current and adapter current conflict, ensuring the normal operation and safety of the circuit. The positive terminal of the battery piece is also connected to the ground through the overvoltage protection diode assembly, which has the same effect as the overvoltage protection diode assembly at the adapter end, protecting the circuit from overvoltage damage. Through the above design, the circuit realizes automatic switching between the adapter and the battery. When the adapter and the battery are connected at the same time, due to the characteristics of the first diode D1 and the switch tube assembly, the adapter power supply has priority, and the battery current cannot flow out, thereby ensuring the priority of the adapter power supply.

[0027] In short, the anti-reverse connection dual power supply switching circuit has a simple structure, which only needs a diode D1, two switch tubes and a resistor R4 to realize the function, reducing the complexity and cost of the circuit. In terms of power consumption, only the power consumption of the 100KΩ resistor is generated when the adapter is powered, and there is no excess power consumption when the battery is powered, effectively reducing the energy consumption of the circuit. The automatic switching between different power supplies is realized by pure hardware circuit, without the need for complex software control, improving the response speed and reliability of the circuit, so that it can quickly adapt to the connection of different power supplies and meet the power supply requirements of electronic devices in different use scenarios.

[0028] Preferably, the overvoltage protection diode assembly includes a first TVS diode D2 and a second TVS diode D3. One end of the first TVS diode D2 is electrically connected with the positive terminal of the battery piece, and the other end of the first TVS diode D2 is grounded. One end of the second TVS diode D3 is electrically connected with the positive terminal of the adapter, and the other end of the second TVS diode D3 is grounded. The first TVS diode D2 and the second TVS diode D3 are both configured to protect the circuit from overvoltage.

[0029] In this embodiment, the overvoltage protection diode assembly plays a crucial role in protecting the circuit. The assembly includes a first TVS diode D2 and a second TVS diode D3. One end of the first TVS diode D2 is electrically connected to the positive terminal of the battery piece, and the other end is grounded; one end of the second TVS diode D3 is electrically connected to the positive terminal of the adapter, and the other end is grounded. Both TVS diodes are configured to effectively clamp the voltage when overvoltage occurs in the circuit, protecting the subsequent circuit from overvoltage damage. For example, when the voltage of the adapter or battery suddenly rises, the TVS diode will quickly conduct, directing the excess voltage to ground, thereby maintaining a stable voltage in the circuit and preventing circuit components from being damaged by overvoltage. This overvoltage protection design greatly improves the reliability and durability of the circuit, extending the service life of the electronic device.

[0030] Preferably, the switch tube assembly includes a first switch tube Q1 and a second switch tube Q2, the control end of the first switch tube Q1 and the control end of the second switch tube Q2 are electrically connected to the positive terminal of the adapter, the first end of the first switch tube Q1 is electrically connected to the positive terminal of the battery piece, the second end of the first switch tube Q1 is electrically connected to the second end of the second switch tube Q2, and the first end of the second switch tube Q2 is electrically connected to the power supply end of the external electronic device.

[0031] Preferably, the first switch tube Q1 and the second switch tube Q2 are both PMOS tubes.

[0032] Preferably, the control end of the first switch tube Q1 is the gate of the PMOS tube, the first end of the first switch tube Q1 is the drain of the PMOS tube, and the second end of the first switch tube Q1 is the source of the PMOS tube.

[0033] Preferably, the control end of the second switch tube Q2 is the gate of the PMOS tube, the first end of the second switch tube Q2 is the drain of the PMOS tube, and the second end of the second switch tube Q2 is the source of the PMOS tube.

[0034] In this embodiment, by combining the high-level cutoff, low-level conduction characteristics of the PMOS tube with the characteristic that the diode reverse current cannot pass, and by the presence of the body diode inside the PMOS tube, the problem of the body diode is solved by adding a PMOS tube in the opposite direction.

[0035] Specifically, the anti-reverse dual power supply switching circuit has multiple situations in actual use, such as adapter reverse connection, battery piece reverse connection, and correct adapter connection, which are described in detail as follows:

[0036] The first case, when the adapter is correctly connected, the battery piece is not connected, the first TVS diode D2 and the second TVS diode D3 adopt the TVS diode, the first TVS diode D2 and the second TVS diode D3 are turned on, the purpose is to protect the subsequent circuit and prevent overvoltage. Then, the first diode D1 is turned on, the second switch tube Q2 is cut off but the current flows through the body diode inside the second switch tube Q2 to the first switch tube Q1, the first switch tube Q1 is cut off and the current cannot pass through the internal body diode, so the power supply voltage is the adapter voltage.

[0037] The second case, when the adapter is not connected, the battery piece is correctly connected, the first TVS diode D2 and the second TVS diode D3 are turned on to protect the subsequent circuit and prevent overvoltage; the first switch tube Q1 and the second switch tube Q2 are turned on, the first diode D1 is cut off, and the current cannot flow through the first diode D1, so the power supply voltage is the battery voltage.

[0038] The third case, when the adapter is correctly connected, the battery piece is also correctly connected, the first TVS diode D2 and the second TVS diode D3 are turned on to protect the subsequent circuit and prevent overvoltage; the first diode D1 is turned on, the second switch tube Q2 is cut off but the current flows through the body diode inside the second switch tube Q2 to the first switch tube Q1, the first switch tube Q1 is cut off and the current cannot pass through the internal body diode, the battery current cannot flow out, so the power supply voltage is the adapter voltage.

[0039] The fourth case, when the adapter is reversed, the current flows through the resistor R4, the resistance value of the resistor R4 is 100KΩ, which will not cause damage to the adapter; the current of the rear-end circuit is cut off by the first diode D1 and cannot be short-circuited.

[0040] The fifth case, when the battery piece is reversed, the first switch tube Q1, the second switch tube Q2 and the first diode D1 are cut off, and the current of the rear-end circuit cannot be short-circuited through the first switch tube Q1, the second switch tube Q2 and the first diode D1.

[0041] In summary, the anti-reverse connection double power supply switching circuit uses simple electronic devices to achieve automatic switching between the adapter and the battery, replaces the need for program judgment in the past, avoids the risk of program bugs, and reduces the workload of software; and reacts quickly, compared with the traditional program control path scheme, there is no large delay, basically no delay. When the adapter and the battery are connected at the same time, due to the characteristics of the first diode and the switch tube assembly, the adapter power supply is preferred, and the battery current cannot flow out, thereby ensuring the priority of the adapter power supply. Specifically, in terms of structure, the circuit structure is simple, only one diode, two PMOS tubes, two TVS diodes and one resistor are needed to realize the function, which reduces the complexity and cost of the circuit. In terms of power consumption, only the power consumption of the 100KΩ resistor is generated when the adapter is powered, and there is no excess power consumption when the battery is powered, effectively reducing the energy consumption of the circuit. And when the adapter or the battery is inserted reversely, the circuit can effectively protect the circuit to prevent the circuit board from being damaged. In addition, the automatic switching between different power supplies is realized by a pure hardware circuit, without the need for complex software control, which improves the response speed and reliability of the circuit, so that it can quickly adapt to the connection of different power supplies, and meet the power supply requirements of electronic devices in different use scenarios.

[0042] The second embodiment of the utility model discloses an electronic equipment, it includes equipment body and the anti-reverse connection double power supply switching circuit of any one described above, the anti-reverse connection double power supply switching circuit is configured in the equipment body inside.

[0043] The above is only the preferred embodiment of the utility model, the protection scope of the utility model is not only limited to the above-mentioned embodiment, all technical solutions under the idea of the utility model belong to the protection scope of the utility model.

Claims

1. A dual power supply switching circuit with reverse connection protection, characterized in that, include: The device comprises an adapter, a battery cell, a switching transistor assembly, a first diode, an overvoltage protection diode assembly, and a resistor. The adapter is used to connect to an external power source. The positive terminal of the adapter is electrically connected to the power supply terminal of an external electronic device through the first diode. The positive terminal of the adapter is grounded through the overvoltage protection diode assembly and the resistor. The positive terminal of the battery cell is electrically connected to the power supply terminal of the external electronic device through the switching transistor assembly and the positive terminal of the battery cell is grounded through the overvoltage protection diode assembly. The switching transistor assembly is configured such that it is turned on only when the positive and negative terminals of the battery cell are correctly connected, and is turned off in all other cases. The first diode is configured such that it conducts when the positive and negative terminals of the adapter are correctly connected, and is cut off in all other cases.

2. The reverse-connection-protected dual power supply switching circuit according to claim 1, characterized in that, The overvoltage protection diode assembly includes a first TVS diode and a second TVS diode. One end of the first TVS diode is electrically connected to the positive terminal of the battery cell, and the other end of the first TVS diode is grounded. One end of the second TVS diode is electrically connected to the positive terminal of the adapter, and the other end of the second TVS diode is grounded. Both the first TVS diode and the second TVS diode are configured as protection circuits to prevent overvoltage.

3. The reverse-connection-protected dual power supply switching circuit according to claim 1, characterized in that, The switching transistor assembly includes a first switching transistor and a second switching transistor. The control terminals of the first switching transistor and the second switching transistor are electrically connected to the positive terminal of the adapter. The first terminal of the first switching transistor is electrically connected to the positive terminal of the battery cell. The second terminal of the first switching transistor is electrically connected to the second terminal of the second switching transistor. The first terminal of the second switching transistor is electrically connected to the power supply terminal of an external electronic device.

4. The reverse-connection-protected dual power supply switching circuit according to claim 3, characterized in that, Both the first and second switching transistors are PMOS transistors.

5. The reverse-connection-protected dual power supply switching circuit according to claim 4, characterized in that, The control terminal of the first switch is the gate of the PMOS transistor, the first terminal of the first switch is the drain of the PMOS transistor, and the second terminal of the first switch is the source of the PMOS transistor.

6. The reverse-connection-protected dual power supply switching circuit according to claim 4, characterized in that, The control terminal of the second switch is the gate of the PMOS transistor, the first terminal of the second switch is the drain of the PMOS transistor, and the second terminal of the second switch is the source of the PMOS transistor.

7. The reverse-connection-protected dual power supply switching circuit according to claim 1, characterized in that, The resistor has a value of 100KΩ.

8. The reverse-connection-protected dual power supply switching circuit according to claim 1, characterized in that, The positive terminal of the first diode is electrically connected to the positive terminal of the adapter, and the negative terminal of the first diode is electrically connected to the power supply terminal of the external electronic device.

9. An electronic device, characterized in that, It includes a device body and a reverse-connection-proof dual power supply switching circuit as described in any one of claims 1 to 8, wherein the reverse-connection-proof dual power supply switching circuit is disposed inside the device body.

Images