Low-voltage power supply input protection circuit

Abstract

The utility model discloses a low-voltage power supply input protection circuit, which comprises a power supply input end, a voltage stabilizing diode, a resettable fuse, a filter capacitor and a Schottky diode, the voltage stabilizing diode is connected between the power supply input ends and is used for overvoltage protection; the resettable fuse is connected in series with the positive electrode of a power supply and is used for overcurrent protection; the filter capacitor is connected in parallel with a power supply input end and is used for filtering high-frequency noise and stabilizing power supply input voltage; and the Schottky diode is connected in series with the power supply input end and is used for polarity protection. The low-voltage power supply input protection circuit can effectively improve the reliability and stability of power supply input, protect circuit elements from being influenced by overvoltage, overcurrent and reverse connection, and ensure the stable operation of a system.

Description

Technical Field

[0001] The utility model relates to the technical field of protection circuits, and more specifically, to a low-voltage power input protection circuit. Background Art

[0002] In electronic devices, the stability and reliability of low-voltage power inputs are crucial. However, power inputs can be susceptible to issues such as overvoltage, overcurrent, and reverse connection, which can damage circuit components and affect system operation. Therefore, an effective power input protection circuit is needed to address these issues. Utility Model Content

[0003] In order to overcome the above-mentioned defects of the prior art, an embodiment of the present invention provides a low-voltage power input protection circuit. The technical problem to be solved by the present invention is: the low-voltage power input protection circuit can effectively improve the reliability and stability of the power input, protect circuit components from overvoltage, overcurrent and reverse connection, and ensure the stable operation of the system.

[0004] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0005] A low voltage power input protection circuit includes a power input terminal, a voltage stabilizing diode, a self-recovery fuse, a filter capacitor and a Schottky diode;

[0006] The voltage stabilizing diode is connected between the power input terminals for overvoltage protection; the self-recovery fuse is connected in series to the positive electrode of the power supply for overcurrent protection;

[0007] The filter capacitor is connected in parallel to the power input terminal to filter out high-frequency noise and stabilize the power input voltage;

[0008] The Schottky diode is connected in series to the power input end for polarity protection.

[0009] like Figure 1 As shown, the specific implementation is: the voltage stabilizing diode is turned on when the power supply voltage exceeds its clamping voltage, absorbing the overvoltage to protect the circuit.

[0010] In a preferred embodiment, the resettable fuse increases resistance to limit the current when the current is too large, and returns to the initial state after the overcurrent disappears.

[0011] In a preferred embodiment, the filter capacitor can effectively filter out high-frequency noise, stabilize the power input voltage, and ensure the normal operation of the circuit.

[0012] In a preferred embodiment, the Schottky diode ensures that the positive and negative poles of the power supply are correctly connected to prevent circuit damage caused by reverse connection.

[0013] Compared with the prior art, the beneficial effects of the present invention are:

[0014] Overvoltage protection: The power supply input voltage is limited by the Zener diode. When the voltage exceeds the regulated value, the Zener diode turns on and discharges the excess voltage energy to the ground, effectively protecting the subsequent circuits from overvoltage damage.

[0015] Overcurrent protection: A self-resetting fuse is used. When the current exceeds the set value, the fuse increases resistance to limit the current, which plays a protective role. After the overcurrent phenomenon disappears, it can return to the initial state and can be reused.

[0016] Filtering function: The capacitor installed at the power input end can filter out high-frequency noise, stabilize the power input voltage, and ensure the normal operation of the circuit.

[0017] Polarity protection: Schottky diodes provide polarity protection to prevent damage to the circuit caused by reverse power connection and ensure that the positive and negative poles of the power supply are connected correctly.

[0018] Combining the above measures, the low-voltage power input protection circuit can effectively improve the reliability and stability of the power input, protect circuit components from overvoltage, overcurrent and reverse connection, and ensure the stable operation of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a circuit diagram of a low-voltage power input protection circuit proposed by the utility model. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0021] Reference Figure 1 , a low voltage power input protection circuit, including a power input terminal, a voltage regulator diode, a self-recovery fuse, a filter capacitor and a Schottky diode;

[0022] The voltage regulator diode is connected between the power input terminals for overvoltage protection; the self-recovery fuse is connected in series with the positive pole of the power supply for overcurrent protection;

[0023] The filter capacitor is connected in parallel at the power input to filter out high-frequency noise and stabilize the power input voltage;

[0024] A Schottky diode is connected in series at the power input for polarity protection.

[0025] like Figure 1 As shown, the specific implementation is as follows: the voltage regulator diode is turned on when the power supply voltage exceeds its clamping voltage, absorbing the overvoltage to protect the circuit.

[0026] In a preferred embodiment, the resettable fuse increases resistance to limit the current when the current is too large, and returns to the initial state after the overcurrent disappears.

[0027] In a preferred embodiment, the filter capacitor can effectively filter out high-frequency noise, stabilize the power input voltage, and ensure normal operation of the circuit.

[0028] In a preferred embodiment, the Schottky diode ensures that the positive and negative poles of the power supply are correctly connected to prevent reverse connection from causing circuit damage.

[0029] Compared with the prior art, the beneficial effects of the present invention are:

[0030] Overvoltage protection: The power supply input voltage is limited by the Zener diode. When the voltage exceeds the regulated value, the Zener diode turns on and discharges the excess voltage energy to the ground, effectively protecting the subsequent circuits from overvoltage damage.

[0031] Overcurrent protection: A self-resetting fuse is used. When the current exceeds the set value, the fuse increases resistance to limit the current, which plays a protective role. After the overcurrent phenomenon disappears, it can return to the initial state and can be reused.

[0032] Filtering function: The capacitor installed at the power input end can filter out high-frequency noise, stabilize the power input voltage, and ensure the normal operation of the circuit.

[0033] Polarity protection: Schottky diodes provide polarity protection to prevent damage to the circuit caused by reverse power connection and ensure that the positive and negative poles of the power supply are connected correctly.

[0034] Combining the above measures, the low-voltage power input protection circuit can effectively improve the reliability and stability of the power input, protect circuit components from overvoltage, overcurrent and reverse connection, and ensure the stable operation of the system.

[0035] The above description is merely illustrative of certain exemplary embodiments of the present invention. It goes without saying that those skilled in the art will be able to modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and description are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A low voltage power input protection circuit, characterized in that: Including power input terminal, voltage regulator diode, self-recovery fuse, filter capacitor and Schottky diode; The voltage stabilizing diode is connected between the power input terminals for overvoltage protection; the self-recovery fuse is connected in series to the positive electrode of the power supply for overcurrent protection; The filter capacitor is connected in parallel to the power input terminal to filter out high-frequency noise and stabilize the power input voltage; The Schottky diode is connected in series to the power input end for polarity protection.

2. The low voltage power input protection circuit according to claim 1, wherein: The voltage stabilizing diode is turned on when the power supply voltage exceeds its clamping voltage, absorbing the overvoltage to protect the circuit.

3. The low voltage power input protection circuit according to claim 2, wherein: The resettable fuse increases resistance to limit the current when the current is too large, and returns to its initial state after the overcurrent disappears.

4. The low voltage power input protection circuit according to claim 3, wherein: The filter capacitor can effectively filter out high-frequency noise, stabilize the power input voltage, and ensure the normal operation of the circuit.

5. The low voltage power input protection circuit according to claim 4, characterized in that: The Schottky diode ensures that the positive and negative poles of the power supply are correctly connected to prevent reverse connection from causing circuit damage.

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