Power supply positive and negative electrode anti-reverse circuit

Abstract

The invention discloses a power supply positive and negative electrode anti-reverse circuit which comprises a power supply loop composed of a power supply positive electrode, a power supply negative electrode, a high-voltage end and a grounding end, the power supply positive electrode and the high-voltage end are conducted to form a positive electrode circuit, and the power supply negative electrode and the grounding end are conducted to form a negative electrode circuit. The first transistor is arranged on the negative electrode circuit to control the conduction of the negative electrode circuit, the first end of the first transistor is electrically connected to the negative electrode of the power supply, the second end of the first transistor is electrically connected to the grounding end, and the control end of the first transistor is electrically connected to the positive electrode circuit; the discharging circuit connected in parallel with the first transistor is used for rapidly reducing the voltage of the control end of the first transistor through discharging when the positive electrode and the negative electrode of the power supply loop are connected reversely, so that the first transistor is turned off, power supply backflow is cut off, and an effective protection effect is achieved.

Description

Technical Field

[0001] The present application relates to the technical field of power supply circuit protection, and in particular to a power supply positive and negative pole anti-reverse circuit. Background Art

[0002] The input of DC power supply usually has fixed polarity. If the positive and negative poles are connected in reverse, it may cause damage to the power supply components and even burn out the key core components of the system, such as MCU (microcontroller unit), FPGA (field programmable gate array) and other high-value chips. This damage will not only cause system failure, but may also trigger a series of chain reactions, resulting in more serious consequences. Therefore, adding an anti-reverse connection protection circuit at the power input is crucial to protect the entire board and its core components.

[0003] The basic function of the reverse connection protection circuit is to prevent the conduction of current when the positive and negative poles of the power supply are reversed, thereby protecting the subsequent circuit from damage. This protection measure can effectively avoid irreversible damage caused by reverse polarity connection. However, the current conventional reverse connection protection circuit has a significant problem when dealing with sudden changes in power polarity: the capacitor voltage connected in parallel to the GS pole of the MOS tube cannot change suddenly, causing the MOS tube to remain in the on state at the moment when the power polarity suddenly changes. This on state may cause a short circuit in the subsequent circuit, thereby burning the key components of the entire system and posing a serious safety hazard. Summary of the invention

[0004] In order to overcome the above shortcomings, the purpose of this application is to provide a power supply positive and negative pole anti-reverse circuit, thereby effectively solving the above technical problems.

[0005] In order to achieve the above objectives, this application adopts the following technical solutions:

[0006] The present application provides a power supply positive and negative electrode anti-reverse circuit, comprising a power supply loop consisting of a positive power supply electrode, a negative power supply electrode, a high voltage terminal and a ground terminal, wherein the positive power supply electrode is connected to the high voltage terminal to form a positive circuit, and the negative power supply electrode is connected to the ground terminal to form a negative circuit.

[0007] The device further comprises a first transistor, which is arranged on the negative electrode circuit to control the conduction of the negative electrode circuit, wherein a first terminal of the first transistor is electrically connected to the negative electrode of the power supply, a second terminal of the first transistor is electrically connected to the ground terminal, and a control terminal of the first transistor is electrically connected to the positive electrode circuit.

[0008] It also includes a discharge circuit composed of a second transistor and a first capacitor, and the discharge circuit is used to reduce the voltage of the control end of the first transistor by discharging when the positive and negative poles of the power supply circuit are connected reversely to turn off the first transistor.

[0009] Further, the first end of the second transistor is electrically connected to the positive circuit, the second end of the second transistor is electrically connected to the first end of the first capacitor, the second end of the first capacitor is electrically connected to the negative circuit, and the control end of the second transistor is electrically connected to the negative circuit.

[0010] Furthermore, the control terminal of the first transistor is electrically connected to the first node on the positive circuit.

[0011] The first end of the second transistor is electrically connected to a second node on the positive circuit, the first node is close to the high voltage end, and the second node is close to the positive electrode of the power supply.

[0012] Furthermore, the second end of the first capacitor is electrically connected to a third node on the negative electrode circuit.

[0013] The control terminal of the second transistor is electrically connected to a fourth node on the negative electrode circuit, the third node is close to the ground terminal, and the fourth node is close to the negative electrode of the power supply.

[0014] Furthermore, a first resistor is provided on the circuit connecting the first transistor control terminal and the positive electrode circuit.

[0015] Furthermore, a second resistor is provided on the circuit connecting the second transistor control terminal and the cathode circuit.

[0016] Furthermore, a diode is also provided on the circuit connecting the second transistor control terminal and the cathode circuit.

[0017] Furthermore, it also includes a second capacitor, a third capacitor and a fourth capacitor, and the second capacitor, the third capacitor and the fourth capacitor are respectively connected in parallel in the power supply circuit.

[0018] Beneficial Effects

[0019] The present application provides a power supply positive and negative pole anti-reverse circuit, which uses a discharge circuit connected in parallel with a first transistor to quickly reduce the voltage at the control end of the first transistor through discharge when the positive and negative poles of the power supply circuit are reversed to shut it down, cut off the power supply reflux, and realize the rapid shutdown of the MOS tube at the moment of sudden change of power polarity, thereby effectively protecting the key components in the subsequent circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide an understanding of the technical solution of the present disclosure and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the technical solution of the present disclosure and do not constitute a limitation on the technical solution of the present disclosure. The shapes and sizes of the components in the accompanying drawings do not reflect the actual proportions and are only intended to illustrate the content of the present application.

[0021] Figure 1 Schematic diagram of the structure of the power supply positive and negative pole anti-reverse circuit in one embodiment of the present application. DETAILED DESCRIPTION

[0022] The above scheme is further described below in conjunction with specific examples. It should be understood that these examples are used to illustrate the present application and are not limited to the scope of the present application. The implementation conditions adopted in the examples can be further adjusted as the conditions of the specific manufacturer, and the unspecified implementation conditions are usually the conditions in conventional experiments.

[0023] Unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present disclosure should be understood by people with ordinary skills in the field to which the present application belongs. The "first", "second" and similar words used in the embodiments of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. "Including" or "comprising" and similar words mean that the elements or objects appearing in front of the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connecting" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. In this article, "electrical connection" includes the situation where the constituent elements are connected together through an element with some electrical function. "Elements with some electrical function" are not particularly limited as long as they can transfer electrical signals between the connected constituent elements. "Elements with some electrical function" can be, for example, electrodes or wiring, or switching elements such as transistors, or other functional elements such as resistors, inductors or capacitors. "Up", "down", "left", "right", etc. are only used to indicate relative position relationships. When the absolute position of the object being described changes, the relative position relationship may also change accordingly.

[0024] In this application, the directions or positional relationships indicated by the terms "upper", "lower", "inner", "middle", etc. are based on the directions or positional relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific direction, or to be constructed and operated in a specific direction.

[0025] As described in the background technology, the conventional reverse connection protection circuit has a significant problem when dealing with sudden changes in power polarity: the voltage of the capacitor connected in parallel to the GS pole of the MOS tube cannot change suddenly, causing the MOS tube to remain in the on state at the moment of sudden change in power polarity. This on state may cause a short circuit in the subsequent circuit, thereby burning key components of the entire system and posing serious safety hazards.

[0026] By optimizing the GS pole voltage drop mechanism, the reverse polarity protection circuit can cut off the current in a shorter time and protect the subsequent circuit from damage caused by reverse polarity. This improvement is crucial for modern electronic systems, especially those automotive electronic systems that rely on precision control and efficient computing. Through this reverse polarity protection measure, it can ensure that the system can still operate safely and stably under the most extreme electrical conditions, protect key core components, extend the service life of the system, and ultimately improve the overall reliability of the system.

[0027] Therefore, the inventor provides a power supply positive and negative pole anti-reverse circuit, which includes a power supply loop consisting of a positive power supply, a negative power supply, a high voltage terminal and a ground terminal, wherein the positive power supply and the high voltage terminal are connected to form a positive circuit, and the negative power supply and the ground terminal are connected to form a negative circuit. It also includes a first transistor, which is arranged on the negative circuit to control the conduction of the negative circuit. The first end of the first transistor is electrically connected to the negative power supply, the second end of the first transistor is electrically connected to the ground terminal, and the control end of the first transistor is electrically connected to the positive circuit. It also includes a discharge circuit consisting of a second transistor and a first capacitor, and the discharge circuit is used to reduce the voltage of the control end of the first transistor by discharging when the positive and negative poles of the power supply loop are reversed to turn off the first transistor.

[0028] The present application uses a discharge circuit connected in parallel with the first transistor to quickly reduce the voltage at the control end of the first transistor through discharge when the positive and negative poles of the power supply circuit are reversed to turn it off, cut off the power supply reflux, and realize the rapid shutdown of the MOS tube at the moment of sudden change in power polarity, thereby effectively protecting the key components in the subsequent circuit.

[0029] Next, combine the attached Figure 1 The present application is described exemplarily.

[0030] An embodiment of the present application provides a power supply positive and negative polarity anti-reverse circuit, the circuit comprising:

[0031] The power supply circuit consists of the positive electrode VBAT+, the negative electrode VBAT-, the high voltage terminal VGH and the ground terminal GND. The positive electrode VBAT+ and the high voltage terminal GND are connected to form a positive circuit V+, and the negative electrode VBAT- and the ground terminal GND are connected to form a negative circuit V-.

[0032] The first transistor M1 is also included. The first transistor is a MOS tube. The first transistor M1 is arranged on the negative circuit V- to control the conduction of the negative circuit V-. The first end 1 of the first transistor M1 is electrically connected to the negative power supply VBAT-, the second end 2 of the first transistor M1 is electrically connected to the ground end GND, and the control end 3 of the first transistor M1 is electrically connected to the positive circuit V+.

[0033] It also includes a discharge circuit composed of a second transistor Q1 and a first capacitor C1, and the discharge circuit is used to reduce the voltage of the control end of the first transistor by discharging when the positive and negative poles of the power supply circuit are reversed to turn off the first transistor, wherein the first end 1 of the second transistor Q1 is electrically connected to the positive circuit V+, the second end 2 of the second transistor Q1 is electrically connected to the first end of the first capacitor C1, the second end of the first capacitor C1 is electrically connected to the negative circuit V-, and the control end 3 of the second transistor Q1 is electrically connected to the negative circuit V-, wherein:

[0034] The control terminal 3 of the first transistor M1 is electrically connected to the first node A on the positive circuit V+, the first terminal 1 of the second transistor Q1 is electrically connected to the second node B on the positive circuit V+, the first node A is close to the high voltage terminal VGH, and the second node B is close to the positive power supply VBAT+;

[0035] The second end of the first capacitor C1 is electrically connected to a third node C on the negative circuit V-, the control end 3 of the second transistor Q1 is electrically connected to a fourth node D on the negative circuit V-, the third node C is close to the ground end GND, and the fourth node D is close to the negative power supply VBAT-.

[0036] The principle of the power supply positive and negative pole anti-reverse circuit provided in this embodiment is:

[0037] When the circuit is operating normally, there is a voltage in the positive circuit V+ formed by the power supply positive electrode VBAT+ and the high-voltage terminal VGH being connected, and the voltage generates a voltage at the control terminal 3 of the first transistor M1 through the first node A, and the first transistor M1 is turned on, thereby turning on the entire power supply loop. At the same time, there is no voltage in the negative circuit V- formed by the power supply negative electrode VBAT- and the ground terminal GND being connected. Since the control terminal of the second transistor Q1 is connected to the fourth node D on the negative circuit V-, there is no voltage at the control terminal 3 of the second transistor Q1, and the second transistor Q1 is turned off;

[0038] When the positive and negative poles of the circuit are connected in reverse, there is no voltage in the circuit between the negative pole of the power supply VBAT- and the high voltage terminal VGH. Theoretically, there is no voltage at the control terminal 3 of the first transistor M1, and the first transistor M1 is turned off. However, at the moment when the polarity of the circuit suddenly changes, there is still voltage at the control terminal 3 of the first transistor M1. At this time, the first transistor M1 is still turned on, resulting in damage to key components in the subsequent circuit. At this time, since there is voltage in the circuit between the positive pole of the power supply VBAT+ and the ground terminal GND, there is voltage at the control terminal 3 of the second transistor Q1. The discharge circuit composed of the second transistor Q1 and the first capacitor C1 can quickly pull down the voltage at the control terminal of the first transistor M1, so that the first transistor M1 is quickly turned off, cutting off the power supply circuit, and playing an effective protective role.

[0039] In some embodiments, a first resistor R1 is provided on a circuit connecting the control terminal 3 of the first transistor M1 and the positive circuit V+, and a second resistor R2 is provided on a circuit connecting the control terminal 3 of the second transistor Q1 and the negative circuit V-. The first resistor R1 and the second resistor R2 are current limiting resistors, which can effectively protect the first transistor M1 and the second transistor Q1.

[0040] In some embodiments, a diode D1 is further provided on the circuit connecting the control terminal of the second transistor Q1 and the negative circuit V-. The diode D1 is an anti-reverse diode, which can effectively prevent current backflow, thereby protecting components in the circuit.

[0041] In some embodiments, the circuit also includes a second capacitor C2, a third capacitor C3 and a fourth capacitor C4, which are respectively connected in parallel in the power supply circuit, and the second capacitor C2, the third capacitor C3 and the fourth capacitor C4 play a role in circuit filtering.

[0042] The above embodiments are only for illustrating the technical concept and features of the present application, and their purpose is to enable people familiar with the technology to understand the content of the present application and implement it accordingly, and they cannot be used to limit the protection scope of the present application. Any equivalent transformation or modification made according to the spirit of the present application shall be included in the protection scope of the present application.

Claims

1. A power supply positive and negative pole anti-reverse circuit, characterized in that: A power supply circuit comprising a positive power supply, a negative power supply, a high voltage terminal and a ground terminal, wherein the positive power supply is connected to the high voltage terminal to form a positive circuit, and the negative power supply is connected to the ground terminal to form a negative circuit. The device further comprises a first transistor, which is arranged on the negative electrode circuit to control the conduction of the negative electrode circuit, wherein a first terminal of the first transistor is electrically connected to the negative electrode of the power supply, a second terminal of the first transistor is electrically connected to the ground terminal, and a control terminal of the first transistor is electrically connected to the positive electrode circuit. It also includes a discharge circuit composed of a second transistor and a first capacitor, and the discharge circuit is used to reduce the voltage of the control end of the first transistor by discharging when the positive and negative poles of the power supply circuit are connected reversely to turn off the first transistor.

2. The power supply positive and negative pole anti-reverse circuit according to claim 1, characterized in that: The first end of the second transistor is electrically connected to the positive circuit, the second end of the second transistor is electrically connected to the first end of the first capacitor, the second end of the first capacitor is electrically connected to the negative circuit, and the control end of the second transistor is electrically connected to the negative circuit.

3. The power supply positive and negative pole anti-reverse circuit as claimed in claim 2, characterized in that: The control terminal of the first transistor is electrically connected to a first node on the positive circuit. The first end of the second transistor is electrically connected to a second node on the positive circuit, the first node is close to the high voltage end, and the second node is close to the positive electrode of the power supply.

4. The power supply positive and negative pole anti-reverse circuit as claimed in claim 3, characterized in that: The second end of the first capacitor is electrically connected to a third node on the negative electrode circuit. The control terminal of the second transistor is electrically connected to a fourth node on the negative electrode circuit, the third node is close to the ground terminal, and the fourth node is close to the negative electrode of the power supply.

5. The power supply positive and negative pole anti-reverse circuit according to claim 1, characterized in that: A first resistor is provided on the circuit connecting the first transistor control terminal and the positive electrode circuit.

6. The power supply positive and negative pole anti-reverse circuit as claimed in claim 2, characterized in that: A second resistor is provided on the circuit connecting the second transistor control terminal and the cathode circuit.

7. The power supply positive and negative pole anti-reverse circuit according to claim 6, characterized in that: A diode is also provided on the circuit connecting the second transistor control terminal and the cathode circuit.

8. The power supply positive and negative pole anti-reverse circuit according to claim 1, characterized in that: It also includes a second capacitor, a third capacitor and a fourth capacitor, and the second capacitor, the third capacitor and the fourth capacitor are respectively connected in parallel in the power supply circuit.

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