Electronic switch output short circuit protection device

Abstract

The utility model relates to electronic switch technical field especially relates to an electronic switch output short circuit protection device, including electronic switch module, detection module, comparison module and enable control module, electronic switch module is connected with detection module through output pin, and the output of detection module is connected with the input of comparison module, and the output of comparison module is connected with the input of enable control module, and enable control module is connected with electronic switch module through control pin. Compared with traditional fuse or overcurrent protection circuit, the utility model improves the response speed of short circuit protection, has the advantages such as high robustness, low power consumption.

Description

Technical Field

[0001] This utility model relates to the field of electronic switch technology, and in particular to an electronic switch output short-circuit protection device. Background Technology

[0002] In modern power electronic systems, high-power DC power distribution systems are widely used in communication base stations, data centers, industrial automation, and new energy fields. These systems typically require stable and reliable DC power output for multiple loads, making high-power DC distribution boxes with multiple outputs critical equipment. Currently, these distribution boxes mostly use electronic switches as output control devices to achieve independent on / off control of each output, thereby improving the system's flexibility and manageability.

[0003] Traditional electronic switch control schemes have significant drawbacks when faced with a short circuit in one of the output circuits. When a short circuit fault occurs in a load circuit, the short-circuit current increases rapidly, causing the on-state voltage drop of the electronic switch to rise, which in turn pulls down the input bus voltage. Since multiple outputs typically share the same input power supply, the input voltage drop directly affects other normally operating output circuits, causing output voltage fluctuations or even system instability. This phenomenon is particularly prominent in applications requiring high reliability and low interference, such as precision instruments and critical communication equipment, and can potentially trigger cascading failures or system downtime.

[0004] To address this issue, existing technologies typically employ solutions such as fast-acting fuses and overcurrent protection circuits, but these still have certain limitations. For example, fuses require manual replacement after tripping, reducing system maintainability; and the response speed of overcurrent protection circuits may not be sufficient to completely prevent instantaneous drops in input voltage.

[0005] Therefore, designing a novel electronic switch output short-circuit protection circuit that can quickly shut down the faulty circuit when a short circuit is detected in one output circuit, while ensuring that the output voltage of other circuits is not affected, thereby improving the reliability and robustness of the system, is of great significance. Utility Model Content

[0006] The purpose of this invention is to address the shortcomings of existing technologies by proposing an electronic switch output short-circuit protection device.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] An electronic switch output short-circuit protection device includes an electronic switch module, a detection module, a comparison module, and an enable control module;

[0009] The electronic switch module includes an electronic switch, input pins, output pins, and control pins;

[0010] The detection module includes detection resistors RS1, R2, R3, R4, and R5, and an amplifier;

[0011] The comparison module includes a comparator and a resistor R0;

[0012] The enable control module includes a MOSFET, a unidirectional thyristor, an enable signal, and a resistor R1.

[0013] The electronic switch module is connected to the detection module via an output pin; the output of the detection module is connected to the input of the comparison module; the output of the comparison module is connected to the input of the enable control module; and the enable control module is connected to the electronic switch module via a control pin.

[0014] Furthermore, in the detection module, the first terminal of the detection resistor RS1 is connected to an electronic switch via an output pin; the non-inverting input of the amplifier is connected in sequence to the resistor R2 and the first terminal of the detection resistor RS1, and the inverting input is connected in sequence to the resistor R3 and the second terminal of the detection resistor RS1; one end of the resistor R4 is connected between the resistor R2 and the non-inverting input of the amplifier, and the other end is grounded; one end of the resistor R5 is connected between the resistor R3 and the inverting input of the amplifier, and the other end is connected to the output terminal of the amplifier; the output terminal of the amplifier is connected to the input terminal of the comparator module.

[0015] Furthermore, in the comparison module, the non-inverting input of the comparator is connected to the output of the detection module and receives the detection voltage; the inverting input receives the reference voltage; and the output is connected in sequence to the resistor R0 and the input of the enable control module.

[0016] Furthermore, in the enable control module, the MOS transistor is a small-signal MOS transistor with its source grounded, its drain connected to an electronic switch via a control pin, and its gate connected to the anode of the unidirectional thyristor; the cathode of the unidirectional thyristor is connected to the source of the MOS transistor and the output terminal of the comparator module, respectively; the enable signal is used to drive the MOS transistor and release the unidirectional thyristor; the resistor R1 is connected in parallel with the unidirectional thyristor.

[0017] Furthermore, the electronic switch turns on the output when the control pin goes low and turns off the output when the control pin is left floating.

[0018] Furthermore, the comparator outputs a high level when the detected voltage is greater than the reference voltage; otherwise, it outputs a low level.

[0019] Furthermore, the MOSFET is turned off when the enable signal becomes high, and the control pin becomes low.

[0020] Furthermore, the unidirectional thyristor is turned on when the comparator outputs a high level, and the control pin is left floating.

[0021] The beneficial effects of this utility model are as follows:

[0022] (1) This utility model monitors the output current through a comparison module and, in conjunction with the fast triggering characteristics of a unidirectional thyristor, can shut off the short circuit circuit in a very short time, effectively preventing the short circuit current from impacting the voltage of the input bus. Compared with traditional fuses or overcurrent protection circuits, it improves the response speed of short circuit protection.

[0023] (2) This utility model utilizes the characteristic that a unidirectional thyristor will continue to conduct once it is turned on, so that the fault circuit is kept in a forced shutdown state. Even if the short circuit current disappears, it will not be falsely restored. Moreover, it is maintained by a very small current provided by the enable signal, without the need for external continuous power supply, and has the advantages of high robustness and low power consumption. Attached Figure Description

[0024] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0025] Figure 1 This is a schematic diagram of the module structure of this utility model.

[0026] In the diagram: 01. Electronic switch module, 02. Detection module, 03. Comparison module, 04. Enable control module, S. Electronic switch, S1. Input pin, S2. Output pin, S3. Control pin, RS11. First terminal of detection resistor RS1, RS12. Second terminal of detection resistor RS1, U1. Amplifier, U2. Comparator, V0. Reference voltage, V1. Detection voltage, Q1. MOSFET, Q2. Thyristor, EN. Enable signal. Detailed Implementation

[0027] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. It should be noted that, unless otherwise explicitly specified and limited, the terms "installation", "fixing", and "connection" should be interpreted broadly. For those skilled in the art, the specific meaning of the above terms in this patent can be understood according to the specific circumstances.

[0028] like Figure 1 As shown, an electronic switch output short-circuit protection device includes an electronic switch module 01, a detection module 02, a comparison module 03, and an enable control module 04.

[0029] In this invention, the electronic switch module 01 consists of an electronic switch S, an input pin S1, an output pin S2, and a control pin S3. Specifically, the electronic switch S is a switch that controls the power output. Voltage is input to the electronic switch S through the input pin S1 and output to the detection module 02 through the output pin S2. When the control pin S3 goes low, the electronic switch S turns on and outputs power; when the control pin S3 is floating, the electronic switch S turns off and outputs power.

[0030] In this invention, the detection module 02 consists of detection resistors RS1, R2, R3, R4, and R5, and amplifier U1, used to detect the magnitude of the output current. Specifically, the first terminal RS11 of resistor RS1 is connected to electronic switch S via output pin S2; the non-inverting terminal of amplifier U1 is connected in sequence to resistor R2 and the first terminal RS11 of detection resistor RS1, and the inverting terminal is connected in sequence to resistor R3 and the second terminal RS12 of detection resistor RS1; one end of resistor R4 is connected between resistor R2 and the non-inverting terminal of amplifier U1, and the other end is grounded; one end of resistor R5 is connected between resistor R3 and the inverting terminal of amplifier U1, and the other end is connected to the output terminal of amplifier U1; the output terminal of amplifier U1 is connected to the non-inverting terminal of comparator U2, thereby connecting to comparator module 03.

[0031] It should be noted that the sensing resistors RS1, R2, and R3, along with amplifier U1, constitute a differential amplifier circuit. This circuit amplifies the small voltage drop across the sensing resistor RS1 to a manageable range and outputs the amplified voltage, i.e., the sensing voltage V1. Resistors R2 and R3, connected to the sensing module 02, ensure consistent input impedance between the non-inverting and inverting inputs of amplifier U1. Furthermore, they limit the current input to amplifier U1 when transient high voltages occur across the sensing resistor RS1 due to factors such as sudden changes in inductive load. Additionally, resistors R4 and R5, connected to the sensing module 02 in the aforementioned manner, form a hysteresis window, ensuring that amplifier U1 does not frequently trigger falsely in noisy environments.

[0032] In this invention, the comparison module 03 consists of a comparator U2 and a resistor R0. Specifically, the non-inverting input of the comparator U2 is the detection voltage V1 obtained by the detection module 02; the inverting input is the reference voltage V0; and the output is connected in sequence to the resistor R0 and the cathode of the unidirectional thyristor Q2, thereby connecting to the enable control module 04.

[0033] It should be noted that comparator U2 outputs a high level when the detected voltage V1 is greater than the reference voltage V0; otherwise, it outputs a low level.

[0034] In this invention, the enable control module 04 consists of a MOSFET Q1, a unidirectional thyristor Q2, an enable signal EN, and a resistor R1. Specifically, the MOSFET Q1 is a small-signal MOSFET with its source grounded, its drain connected to the electronic switch S via the control pin S3, and its gate connected to the anode of the unidirectional thyristor Q2. The cathode of the unidirectional thyristor Q2 is connected to the source of the MOSFET Q1. The enable signal EN is used to drive the MOSFET Q1 and release the unidirectional thyristor Q2. The resistor R1 is connected in parallel with the unidirectional thyristor Q2.

[0035] It should be noted that the state of control pin S3 is jointly controlled by the enable signal EN, MOSFET Q1, and unidirectional thyristor Q2. Specifically, when the enable signal EN goes high, MOSFET Q1 is turned off, and control pin S3 goes low; when comparator U2 outputs a high level, unidirectional thyristor U2 is turned on, and control pin S3 is left floating.

[0036] The principle of this invention is as follows: When the electronic switch S is short-circuited, the current flowing to the detection module O2 through the output pin S2 increases sharply. This causes the detection voltage V1 obtained through amplifier U1 to exceed the set reference voltage V0. Comparator U2 then outputs a high level, triggering the unidirectional thyristor Q2 to conduct rapidly. The enable signal EN is pulled low, and the control pin S3 is left floating, causing the electronic switch S to turn off. During the period when the electronic switch S is off, because the unidirectional thyristor Q2 has the characteristic of maintaining its conduction once turned on, the enable signal EN remains low. The sustaining current of the unidirectional thyristor Q2 is provided by the enable signal EN. When it is necessary to restore the output of the electronic switch S, the enable signal EN is further lowered to reduce the sustaining current, releasing the unidirectional thyristor Q2 until it becomes cut off. Then, the enable signal EN is pulled high, causing the MOSFET Q1 to become low and cut off. The control pin S3 then becomes low, allowing the electronic switch S to resume output.

[0037] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A short-circuit protection device for the output of an electronic switch, characterized in that, It includes an electronic switch module, a detection module, a comparison module, and an enable control module; The electronic switch module includes an electronic switch, input pins, output pins, and control pins; The detection module includes detection resistors RS1, R2, R3, R4, and R5, and an amplifier; The comparison module includes a comparator and a resistor R0; The enable control module includes a MOSFET, a unidirectional thyristor, an enable signal, and a resistor R1. The electronic switch module is connected to the detection module via an output pin; the output of the detection module is connected to the input of the comparison module; the output of the comparison module is connected to the input of the enable control module; and the enable control module is connected to the electronic switch module via a control pin.

2. The electronic switch output short-circuit protection device according to claim 1, characterized in that, In the detection module, the first terminal of the detection resistor RS1 is connected to an electronic switch via an output pin; the non-inverting input of the amplifier is connected in sequence to the first terminal of the resistor R2 and the detection resistor RS1, and the inverting input is connected in sequence to the second terminal of the resistor R3 and the detection resistor RS1; one end of the resistor R4 is connected between the resistor R2 and the non-inverting input of the amplifier, and the other end is grounded; one end of the resistor R5 is connected between the resistor R3 and the inverting input of the amplifier, and the other end is connected to the output terminal of the amplifier; the output terminal of the amplifier is connected to the input terminal of the comparator module.

3. The electronic switch output short-circuit protection device according to claim 1, characterized in that, In the comparison module, the non-inverting input of the comparator is connected to the output of the detection module, and the detection voltage is input. The inverting input is the reference voltage; the output is connected in sequence to resistor R0 and the input of the enable control module.

4. The electronic switch output short-circuit protection device according to claim 1, characterized in that, In the enable control module, the MOSFET is a small-signal MOSFET with its source grounded, its drain connected to an electronic switch via a control pin, and its gate connected to the anode of a unidirectional thyristor. The cathode of the unidirectional thyristor is connected to the source of the MOSFET and the output of the comparator module, respectively. The enable signal is used to drive the MOSFET and release the unidirectional thyristor. The resistor R1 is connected in parallel with the unidirectional thyristor.

5. The electronic switch output short-circuit protection device according to claim 1, characterized in that, The electronic switch turns on the output when the control pin goes low and turns off the output when the control pin is left floating.

6. The electronic switch output short-circuit protection device according to claim 3, characterized in that, The comparator outputs a high level when the detected voltage is greater than the reference voltage; otherwise, it outputs a low level.

7. The electronic switch output short-circuit protection device according to claim 4, characterized in that, The MOSFET is turned off when the enable signal goes high, and the control pin goes low.

8. An electronic switch output short-circuit protection device according to claim 4 or 6, characterized in that, The unidirectional thyristor is turned on when the comparator outputs a high level, and the control pin is left floating.

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