Reverse connection prevention protection circuit
By combining a MOSFET and a voltage divider module with a Zener diode in a reverse connection protection circuit, the problem of complex structure in existing technologies is solved, achieving simple and effective reverse connection protection and reducing equipment load.
Patent Information
- Application Number
- CN202422881067.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-25
- Publication Date
- 2025-11-28
- Estimated Expiration
- 2034-11-25
AI Technical Summary
Existing reverse connection protection circuits are complex in structure, which burdens the control circuits of terminal equipment and makes it difficult to effectively prevent input reverse connection problems.
The output is controlled by a MOSFET, and a voltage divider module provides the MOSFET with a conduction voltage. Combined with a Zener diode to protect the MOSFET, and a voltage regulator module to stabilize the output voltage, a simple reverse connection protection circuit is formed.
It effectively prevents input reverse connection with minimal components, protects MOSFETs, reduces the impact of reverse connection voltage, simplifies circuit structure, and reduces the control burden of equipment.
Smart Images
Figure CN223613044U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of low-voltage electrical apparatuses, in particular to a reverse connection protection circuit. BACKGROUND
[0002] In some terminal devices, for example, battery-powered devices, some terminal devices of industrial control type, these devices are designed to have a power supply interface. Since direct current power supply is adopted, the reverse connection of the power supply needs to be considered. In the use process, once the reverse connection occurs, it may cause the internal circuit of the terminal device to be burned out. The existing reverse connection protection circuit uses structures such as diodes, rectifier bridges, and MOS tubes. However, there is still a problem of complex structure, and when applied to specific devices, it still causes a certain burden to the control circuit of the device. CONTENT OF THE UTILITY MODEL
[0003] One of the main purposes of the present application is to provide a reverse connection protection circuit. The MOS tube controls the output, a voltage dividing module is arranged to provide a conduction voltage for the gate of the MOS tube, and the voltage dividing module and the stabilizing diode are used to protect the MOS tube in the reverse connection. With few components, the problem caused by the reverse connection of the input is effectively prevented, and at least one or more problems caused by the limitations and defects of the related art are overcome to some extent.
[0004] To achieve the above application purposes, the present application adopts the following technical solutions:
[0005] According to one aspect of the present application, a reverse connection protection circuit is provided, which includes a voltage dividing module, a MOS tube, a stabilizing diode, and a stabilizing module. The stabilizing module is connected in parallel with the power supply input and the power supply output. The voltage dividing module is connected in parallel with the power supply input and the power supply output. The voltage dividing module includes at least a first voltage dividing and a second voltage dividing connected in series along the current flow direction in the normal working state. The MOS tube is connected in parallel with the stabilizing diode, and the MOS tube is connected in parallel with the second voltage dividing. The gate of the MOS tube is connected to the first voltage dividing. The drain of the MOS tube is connected to the negative electrode of the power supply input. The source of the MOS tube is connected to the negative electrode of the power supply output. The negative electrode of the stabilizing diode is connected to the source of the MOS tube. The positive electrode of the stabilizing diode is connected to the gate of the MOS tube.
[0006] According to one embodiment of the present application, the first voltage dividing includes a first resistor, and the second voltage dividing includes a second resistor.
[0007] According to one embodiment of the present application, the resistance value of the first resistor is 1K ohm, and the resistance value of the second resistor is 10K ohm.
[0008] According to an embodiment of the present application, the input terminal of the three-terminal voltage regulator is connected to an input voltage, the output terminal of the three-terminal voltage regulator is connected to an output voltage, and a plurality of capacitors are connected to the input terminal and the output terminal of the three-terminal voltage regulator respectively.
[0009] According to an embodiment of the present application, the three-terminal voltage regulator is of type 78L05.
[0010] According to an embodiment of the present application, two capacitors are connected in parallel to the input terminal of the three-terminal voltage regulator, and two capacitors are connected in parallel to the output terminal of the three-terminal voltage regulator.
[0011] According to an embodiment of the present application, the capacity of the capacitors is 10UF.
[0012] In the present application, the MOS transistor is provided to control the output of direct current, so that the MOS transistor is turned off to cut off the power output when the input is reversed. The voltage provided by the voltage division module is also beneficial to reduce the input voltage when reversed, and the zener diode is provided to prevent the MOS transistor from being damaged by the breakdown caused by the high input voltage. With few components, the problem caused by the input reverse connection is effectively prevented. The voltage stabilization module is further provided to stabilize the output voltage, which further protects the circuit.
[0013] It should be understood that the foregoing general description and the following detailed description are only exemplary and explanatory, and are not limiting to the present application. BRIEF DESCRIPTION OF DRAWINGS
[0014] The above and other features and advantages of the present application will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which:
[0015] Figure 1 is a schematic diagram of a reverse connection protection circuit according to an exemplary embodiment. DETAILED DESCRIPTION
[0016] Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments, however, can be implemented in many different forms and should not be construed as limited to the implementations set forth herein; rather, these implementations are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. Like reference numerals refer to like elements throughout the specification.
[0017] Reference will now be made to Figure 1In an embodiment, the reverse connection protection circuit comprises a voltage division module, a MOS tube Q1, a voltage stabilizing diode ZD1 and a voltage stabilizing module. The voltage division module is connected in parallel with the power input and the power output, and the voltage stabilizing module is also connected in parallel with the power input and the power output. The voltage division module comprises at least a first voltage division and a second voltage division connected in series along the current flow direction in a normal working state. The MOS tube Q1 is connected in parallel with the voltage stabilizing diode ZD1, and the MOS tube Q1 is connected in parallel with the second voltage division. The gate of the MOS tube Q1 is connected with the first voltage division, the drain of the MOS tube Q1 is connected with the negative pole of the power input, the source of the MOS tube Q1 is connected with the negative pole of the power output, the negative pole of the voltage stabilizing diode ZD1 is connected with the source of the MOS tube Q1, and the positive pole of the voltage stabilizing diode ZD1 is connected with the gate of the MOS tube Q1.
[0018] In a specific embodiment, the power input comprises an input positive pole VIN+ and an input negative pole VIN-, the power output comprises an output positive pole VOUT+ and an output negative pole VOUT-, and the protection circuit is arranged between the power input and the power output.
[0019] In a specific embodiment, the first voltage division comprises a first resistor R1, and the second voltage division comprises a second resistor R2. The resistance of the first resistor R1 is 1K ohm, and the resistance of the second resistor R2 is 10K ohm.
[0020] In a normal connection, the first resistor R1 and the second resistor R2 provide a turn-on voltage for the gate of the MOS tube after voltage division, the source and the drain of the MOS tube are turned on, and the power output can be normally output. In a reverse connection, the diode in the MOS tube is reverse blocked, i.e. the source and the drain of the MOS tube are not turned on, the voltage division module cannot provide a turn-on voltage for the gate of the MOS tube, the MOS tube is cut off, and the power output is turned off.
[0021] In a specific embodiment, the voltage stabilizing module comprises a three-terminal voltage regulator U1 and a plurality of capacitors. The input end of the three-terminal voltage regulator U1 is connected with an input voltage, the output end of the three-terminal voltage regulator U1 is connected with an output voltage, and the input end and the output end of the three-terminal voltage regulator U1 are respectively connected with a plurality of capacitors.
[0022] Preferably, the voltage stabilizing module comprises four capacitors, such as a capacitor C1, a capacitor C2, a capacitor C3 and a capacitor C4, and the three-terminal voltage regulator is selected to be a type 78L05. The input end of the three-terminal voltage regulator U1 is connected in parallel with the capacitor C1 and the capacitor C2, and the output end of the three-terminal voltage regulator U2 is connected in parallel with the capacitor C3 and the capacitor C4. The capacitances of the capacitor C1, the capacitor C2, the capacitor C3 and the capacitor C4 can all be selected to be 10UF.
[0023] The above merely provides preferred embodiments of the application, and is not intended to limit the application. The application can be variously changed and modified by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the application shall fall within the protection scope of the application.
Claims
1. A reverse connection protection circuit, characterized by comprising: The voltage stabilizing module includes a voltage dividing module, a MOS tube, a voltage stabilizing diode and a voltage stabilizing module, the voltage stabilizing module is connected with the power input and the power output in parallel, the voltage dividing module is connected with the power input and the power output in parallel, the voltage dividing module includes a first voltage divider and a second voltage divider connected in series along the current flow direction in the normal working state, the MOS tube is connected with the voltage stabilizing diode in parallel, and the MOS tube is connected with the second voltage divider in parallel, the gate of the MOS tube is connected with the first voltage divider, the drain of the MOS tube is connected with the negative pole of the power input, the source of the MOS tube is connected with the negative pole of the power output, the negative pole of the voltage stabilizing diode is connected with the source of the MOS tube, and the positive pole of the voltage stabilizing diode is connected with the gate of the MOS tube.
2. The reverse-connection protection circuit according to claim 1, wherein The first voltage divider includes a first resistor, and the second voltage divider includes a second resistor.
3. The reverse-connection protection circuit according to claim 2, wherein The resistance of the first resistor is 1K ohm, and the resistance of the second resistor is 10K ohm.
4. The reverse-connection protection circuit according to claim 1, wherein The voltage stabilizing module includes a three-terminal voltage stabilizer and a plurality of capacitors, the input end of the three-terminal voltage stabilizer is connected with the input voltage, the output end of the three-terminal voltage stabilizer is connected with the output voltage, and the input end and the output end of the three-terminal voltage stabilizer are respectively connected with a plurality of capacitors.
5. The reverse-connection protection circuit according to claim 4, wherein The three-terminal voltage stabilizer is selected from a type 78L05.
6. The reverse-connection protection circuit according to claim 4, wherein The input end of the three-terminal voltage stabilizer is connected with two parallel capacitors, and the output end of the three-terminal voltage stabilizer is connected with two parallel capacitors.
7. The reverse-connection protection circuit according to claim 6, wherein The capacity of the capacitor is 10UF.