CN219107283U - Input power failure alarm circuit and switching power supply - Google Patents

Abstract

The embodiment of the utility model discloses an input power failure alarm circuit and a switching power supply, wherein the circuit comprises: diode D1, sampling resistor R1, capacitor CD1, rectifier bridge BR1, diode D2, capacitor CD2, current limiting resistor R2, sampling resistor R3, diode DZ1, optocoupler PC1 and voltage stabilizing reference chip A1; the optocoupler PC1 consists of an optocoupler input end PC1A and an optocoupler output end PC 1B. The utility model can rapidly alarm the terminal when the input of the switching power supply is lost, so that the terminal can rapidly judge which power supply system generates the input lost according to the alarm signal, thereby timely taking the solving measures. The utility model has simple structure and low cost, can reliably realize the input power failure alarm, and is suitable for popularization and application.

Description

Input power failure alarm circuit and switching power supply

Technical Field

The embodiment of the utility model relates to the technical field of power supplies, in particular to an input power failure alarm circuit and a switching power supply.

Background

In many modern application terminals, the power supply is generally provided with two or more sets, so that the application terminal can reliably work or turn off in a delayed manner under the condition that one input source is in a problem. However, the existing switch power supply used in the application terminal does not have a set of reliable input power failure alarm function, when the input power of the switch power supply is lost, the application terminal cannot quickly identify which set of power supply system is lost, and which set of power supply system is currently supplying power to the application terminal, so that the specific condition of the input voltage cannot be judged.

The above problems are to be solved.

Disclosure of Invention

In order to solve the related technical problems, the utility model provides an input power failure alarm circuit and a switching power supply, which are used for solving the problems mentioned in the background art section.

In order to achieve the above purpose, the embodiment of the present utility model adopts the following technical scheme:

in a first aspect, an embodiment of the present utility model provides an input power loss alarm circuit, including: diode D1, sampling resistor R1, capacitor CD1, rectifier bridge BR1, diode D2, capacitor CD2, current limiting resistor R2, sampling resistor R3, diode DZ1, optocoupler PC1 and voltage stabilizing reference chip A1; the optical coupler PC1 consists of an optical coupler input end PC1A and an optical coupler output end PC 1B; the positive pole of diode D1 connects the mains supply input zero line end with rectifier bridge BR 1's first alternating current pin back, diode D2's positive pole is connected with mains supply input fire line end, rectifier bridge BR 1's second alternating current pin, rectifier bridge BR 1's positive pole pin is connected with electric capacity CD 1's one end, and electric capacity CD 1's the other end is connected with rectifier bridge BR 1's negative pole pin back ground, diode D1's negative pole is connected with diode D2's negative pole, electric capacity CD 2's one end, sampling resistor R1's one end, current limiting resistor R2's one end, electric capacity CD 2's the other end is connected with sampling resistor R3's one end, voltage stabilizing reference chip A1's positive pole, voltage stabilizing reference chip A1's the other end is connected with sampling resistor R3's the other end, voltage stabilizing reference chip A1's control electrode, current limiting resistor R2's the other end is connected with light coupling input end PC 1A's positive pole, diode DZ 1's negative pole, light coupling input end PC1A 1's negative pole is connected with the output of reference voltage stabilizing reference chip A1, and the output of warning POWER source POR and the voltage stabilizing electrode is connected with the output of warning POWER source POR and the voltage stabilizing electrode of the warning POWER bridge PC, respectively.

As an alternative embodiment, the diode D1 and the diode D2 are each, but not limited to, a low frequency rectifier diode.

As an alternative embodiment, the diode DZ1 is, but not limited to, a regulator tube; the capacitor CD1 and the capacitor CD2 are electrolytic capacitors, but are not limited thereto.

In a second aspect, an embodiment of the present utility model provides a switching power supply, where the switching power supply uses the input power loss alarm circuit according to any one of the first aspects.

The input power failure alarm circuit and the switching power supply provided by the utility model can quickly alarm the terminal when the switching power supply is input and powered down, so that the terminal can quickly judge which power supply system generates input and powered down according to the alarm signal, and thus, a solving measure can be timely taken. The utility model has simple structure and low cost, can reliably realize the input power failure alarm, and is suitable for popularization and application.

Drawings

For a clearer description and understanding of the technical solutions of the embodiments of the present utility model, the following description will make a brief introduction to the drawings required for the description of the embodiments of the present utility model, and it is obvious that the drawings in the following description are only some embodiments of the present utility model, and other drawings may be obtained according to the contents of the embodiments of the present utility model and the drawings without inventive effort for those skilled in the art.

Fig. 1 is a diagram of an input power failure alarm circuit according to an embodiment of the present utility model.

Detailed Description

In order to make the technical problems solved by the present utility model, the technical solutions adopted and the technical effects achieved more clear, the technical solutions of the embodiments of the present utility model will be described in further detail below with reference to the accompanying drawings, and it is obvious that the described embodiments are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to fall within the scope of the utility model.

Example 1

Referring to fig. 1, fig. 1 is a diagram illustrating an input power loss alarm circuit according to an embodiment of the present utility model.

The input power failure alarm circuit in this embodiment includes: diode D1, sampling resistor R1, capacitor CD1, rectifier bridge BR1, diode D2, capacitor CD2, current limiting resistor R2, sampling resistor R3, diode DZ1, optocoupler PC1 and voltage stabilizing reference chip A1; the optical coupler PC1 consists of an optical coupler input end PC1A and an optical coupler output end PC 1B; the positive pole of diode D1 connects the mains supply input zero line end with rectifier bridge BR 1's first alternating current pin back, diode D2's positive pole is connected with mains supply input fire line end, rectifier bridge BR 1's second alternating current pin, rectifier bridge BR 1's positive pole pin is connected with electric capacity CD 1's one end, and electric capacity CD 1's the other end is connected with rectifier bridge BR 1's negative pole pin back ground, diode D1's negative pole is connected with diode D2's negative pole, electric capacity CD 2's one end, sampling resistor R1's one end, current limiting resistor R2's one end, electric capacity CD 2's the other end is connected with sampling resistor R3's one end, voltage stabilizing reference chip A1's positive pole, voltage stabilizing reference chip A1's the other end is connected with sampling resistor R3's the other end, voltage stabilizing reference chip A1's control electrode, current limiting resistor R2's the other end is connected with light coupling input end PC 1A's positive pole, diode DZ 1's negative pole, light coupling input end PC1A 1's negative pole is connected with the output of reference voltage stabilizing reference chip A1, and the output of warning POWER source POR and the voltage stabilizing electrode is connected with the output of warning POWER source POR and the voltage stabilizing electrode of the warning POWER bridge PC, respectively.

Illustratively, the diode D1 and the diode D2 in this embodiment are each, but not limited to, a low frequency rectifier diode. Illustratively, the diode DZ1 in the present embodiment is, but not limited to, a regulator tube; the capacitor CD1 and the capacitor CD2 are electrolytic capacitors, but are not limited thereto.

Specifically, when the input power failure alarm circuit works in this embodiment, the input LN mains supply is rectified by the rectifier bridge BR1 and filtered by the capacitor CD1 to obtain high-voltage direct current, and the high-voltage direct current is used for supplying power to the high-frequency transformer of the switching power supply through direct current conversion. The input LN mains supply is connected to a diode D1 and a diode D2, respectively, which are preferably low-frequency rectifying diodes, the diode D1 and the diode D2 rectify the alternating current input by L N into direct current, and the capacitor CD2 converts the direct current rectified by the diode D1 and the diode D2 into stable direct current. The sampling resistor R1 and the sampling resistor R3 are voltage sampling resistors, the voltage-stabilizing reference chip A1 can select a voltage-stabilizing reference chip TL431, the reference voltage end of the voltage-stabilizing reference chip A1 is connected with the sampling resistor R1 and the sampling resistor R3, when the voltage sampled by the sampling resistor R3 end is smaller than the reference voltage of the voltage-stabilizing reference chip A1, the voltage of the output end of the voltage-stabilizing reference chip A1 becomes high, the output end of the voltage-stabilizing reference chip A1 is connected with the optocoupler input end PC1A, and no current flows through the optocoupler input end PC1A due to the high level of the output end of the voltage-stabilizing reference chip A1, so that the optocoupler output end PC1B is not conducted; when the voltage sampled by the sampling resistor R3 is larger than the reference voltage of the voltage stabilizing reference chip A1, the voltage of the output end of the voltage stabilizing reference chip A1 becomes lower, the voltage of the optocoupler input end PC1A passes through, one end of the current limiting resistor R2 is connected with the positive electrode of the light emitting diode of the optocoupler input end PC1A, the other end of the current limiting resistor R2 is connected with a positive voltage, when the current passes through the optocoupler input end PC1A, the sampling resistor R3 limits the current passing through the optocoupler input end PC1A to be not too large, otherwise, the optocoupler input light emitting diode is burnt out, and the diode DZ1 serves as a voltage stabilizing tube to limit the voltage of the optocoupler input end PC1A to be below a set range, otherwise, the input light emitting diode of the optocoupler is burnt out. When the light emitting diode of the optocoupler input end PC1A passes through the current, the output triode of the optocoupler output end PC1B is conducted, the POWER failure warning output ends POWER FAIL connected with the two ends of the optocoupler output triode are conducted respectively, otherwise, the two POWER failure warning output ends POWER FAIL are not conducted, and in specific application, the two POWER failure warning output ends POWER FAIL can be connected with the CPU monitoring end of the terminal, so that the CPU can rapidly judge whether the input voltage of the POWER supply is in failure or not according to the connection and disconnection logic relation of the two POWER failure warning output ends POWER FAIL.

The input power failure alarm circuit provided by the utility model can rapidly alarm the terminal when the input power of the switching power supply is lost, so that the terminal can rapidly judge which power supply system generates the input power failure according to the alarm signal, and automatically identify and judge the condition of the input voltage so as to take solving measures in time. The utility model has simple structure and low cost, can reliably realize the input power failure alarm, and is suitable for popularization and application.

Example two

The embodiment of the utility model provides a switching power supply, which adopts the input power failure alarm circuit in the first embodiment. The switch power supply provided by the utility model can rapidly alarm the terminal when the input power fails, so that the terminal can rapidly judge which power supply system generates the input power failure according to the alarm signal, and thus, a solution can be timely adopted.

Note that the above is only a preferred embodiment of the present utility model and the technical principle applied. The present utility model is not limited to the specific embodiments described herein, but is capable of numerous modifications, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the utility model. Therefore, while the utility model has been described in connection with the above embodiments, the utility model is not limited to the embodiments, but may be embodied in many other equivalent forms without departing from the spirit or scope of the utility model, which is set forth in the following claims.

Claims (4)

1. An input power loss alarm circuit, comprising: diode D1, sampling resistor R1, capacitor CD1, rectifier bridge BR1, diode D2, capacitor CD2, current limiting resistor R2, sampling resistor R3, diode DZ1, optocoupler PC1 and voltage stabilizing reference chip A1; the optical coupler PC1 consists of an optical coupler input end PC1A and an optical coupler output end PC 1B; the positive pole of diode D1 connects the mains supply input zero line end with rectifier bridge BR 1's first alternating current pin back, diode D2's positive pole is connected with mains supply input fire line end, rectifier bridge BR 1's second alternating current pin, rectifier bridge BR 1's positive pole pin is connected with electric capacity CD 1's one end, and electric capacity CD 1's the other end is connected with rectifier bridge BR 1's negative pole pin back ground, diode D1's negative pole is connected with diode D2's negative pole, electric capacity CD 2's one end, sampling resistor R1's one end, current limiting resistor R2's one end, electric capacity CD 2's the other end is connected with sampling resistor R3's one end, voltage stabilizing reference chip A1's positive pole, voltage stabilizing reference chip A1's the other end is connected with sampling resistor R3's the other end, voltage stabilizing reference chip A1's control electrode, current limiting resistor R2's the other end is connected with light coupling input end PC 1A's positive pole, diode DZ 1's negative pole, light coupling input end PC1A 1's negative pole is connected with the output of reference voltage stabilizing reference chip A1, and the output of warning POWER source POR and the voltage stabilizing electrode is connected with the output of warning POWER source POR and the voltage stabilizing electrode of the warning POWER bridge PC, respectively.

2. The input power loss warning circuit according to claim 1, wherein the diode D1 and the diode D2 are each, but not limited to, a low frequency rectifier diode.

3. The input power loss alarm circuit according to claim 2, wherein the diode DZ1 adopts a voltage stabilizing tube; the capacitor CD1 and the capacitor CD2 are electrolytic capacitors, but are not limited thereto.

4. A switching power supply, characterized in that it adopts the input power loss warning circuit according to any one of claims 1 to 3.

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