An electronic switch short-circuit protection circuit

Abstract

This utility model relates to the field of electronic switch technology, specifically to an electronic switch short-circuit protection circuit. It includes an electronic switch circuit connected in series with the load to perform the switching action of the load, and further includes: a first short-circuit detection circuit, a second short-circuit detection circuit, and a short-circuit triggering and latching circuit connected to the electronic switch circuit. When a short circuit occurs in the load of the electronic switch circuit, a short-circuit voltage is generated on the switching device of the electronic switch circuit and the current detection device of the second short-circuit detection circuit. The first short-circuit detection circuit converts the short-circuit voltage on the switching device of the electronic switch circuit into a first trigger signal for the short-circuit triggering and latching circuit. Besides protecting the electronic switch device from damage by large current surges when a short circuit occurs, this utility model patent, more importantly, improves the anti-interference capability of the short-circuit protection circuit, making it less prone to malfunctions and thus enhancing the stability of the electronic switch.

Description

Technical Field

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

[0002] The common practice for short-circuit protection in existing electronic switches is to connect a fuse in series in the main circuit. When a short circuit occurs in the load, the switching device of the electronic switch will basically be damaged as well. Alternatively, an electronic short-circuit protection circuit can be added. However, these circuits are triggered to shut down the switching device after a short circuit is detected. Since there is only one trigger signal, it is easily interfered with, especially when there is a large signal interference source nearby. The short-circuit circuit may malfunction, affecting the stability of the electronic switch. Utility Model Content

[0003] The main purpose of this utility model is to provide a short-circuit protection circuit for electronic switches, so as to solve the problem that the short-circuit protection of existing electronic switches in related technologies is easily interfered with due to the single condition of only one trigger signal, especially when there is a large signal interference source nearby, the short-circuit circuit will malfunction, affecting the stability of the electronic switch.

[0004] To achieve the above objectives, according to one aspect of the present invention, an electronic switch short-circuit protection circuit is provided, comprising: an electronic switch circuit connected in series with a load and performing the on / off action of the load, characterized in that it further comprises: a first short-circuit detection circuit, a second short-circuit detection circuit, and a short-circuit triggering and latching circuit connected to the electronic switch circuit.

[0005] The electronic switching circuit is configured to generate a first short-circuit voltage on the switching device of the electronic switching circuit in response to a short circuit occurring in the load.

[0006] The short-circuit first detection circuit is configured to convert the first short-circuit voltage on the switching device of the electronic switching circuit into a first trigger signal for the short-circuit trigger and latching circuit.

[0007] The short-circuit second detection circuit is configured to: generate a second short-circuit voltage on the current sensing device of the short-circuit second detection circuit in response to a short circuit in the load, and generate a second trigger signal required for the short-circuit trigger and latching circuit based on the second short-circuit voltage;

[0008] The short-circuit triggering and latching circuit is configured to shut down the electronic switch circuit in response to receiving both the first trigger signal and the second trigger signal, in order to perform short-circuit protection.

[0009] Furthermore, the electronic switching circuit uses a combination of rectifier devices and switching devices or dual switching devices to perform load switching operations, including a reverse freewheeling diode, a decoupling diode, and at least one resistor connected in parallel with the switching device.

[0010] Furthermore, in the method of using a rectifier and a switching device to perform the load switching operation, the second input terminal of the rectifier is connected to one end of the load, the other end of the load is connected to the neutral line of the mains, the first input terminal of the rectifier is connected to the live line of the mains, the first output terminal of the rectifier is connected to the first current terminal of the switching device and is connected to the input terminal of the first short-circuit detection circuit, the control terminal of the switching device is connected to the output terminal of the short-circuit trigger and latch circuit and is connected to the drive circuit through a resistor, the second current terminal of the switching device is connected to the first port of the second short-circuit detection circuit, and the second output terminal of the rectifier is connected to the second port of the second short-circuit detection circuit.

[0011] Furthermore, in the method of using complementary dual switching devices to perform load switching operations, the first current terminal of switching device 1 is connected to the mains live wire, and its second current terminal is connected to the first port of the second short-circuit detection circuit; the first current terminal of switching device 2 is connected to one end of the load, the other end of the load is connected to the mains neutral wire, and the second current terminal of switching device 2 is connected to the second port of the second short-circuit detection circuit; the first current terminals of the two switching devices are respectively connected to the input terminal of the first short-circuit detection circuit through decoupling diodes; the control terminals of the two switching devices are respectively connected to the output terminal of the short-circuit trigger and latch circuit through decoupling diodes, and are respectively connected to the drive circuit through resistors; two reverse freewheeling diodes are respectively connected in parallel to the first and second current terminals of the two switching devices.

[0012] Furthermore, the first short-circuit detection circuit includes a short-circuit voltage sampling circuit and a voltage signal conversion circuit. If the voltage signal obtained by the short-circuit voltage sampling circuit meets the trigger signal requirements of the short-circuit trigger and latch circuit, then the voltage signal conversion circuit is not needed, and it is directly used as the first trigger signal of the short-circuit trigger and latch circuit; if it does not meet the requirements, the voltage signal conversion circuit is needed to convert it into the first trigger signal required by the short-circuit trigger and latch circuit. The input terminal of the first short-circuit detection circuit is connected to the electronic switch circuit, and its output terminal is connected to the short-circuit trigger and latch circuit.

[0013] Furthermore, the short-circuit voltage sampling circuit includes a voltage divider resistor device, a bypass capacitor device, and a voltage limiting device. The short-circuit voltage sampling circuit divides the short-circuit voltage from the electronic switch circuit using the voltage divider resistor device. A bypass capacitor is connected in parallel with the upper voltage divider resistor device to improve the sampling speed; a voltage limiting device is connected in parallel with the lower voltage divider resistor device to protect subsequent circuits.

[0014] Furthermore, the voltage signal conversion circuit includes any one or more of an amplifying device, a comparating device, a filtering device, and a resistive device. The voltage signal conversion circuit is configured to convert the voltage signal obtained from the short-circuit voltage sampling circuit into a first trigger signal required by the short-circuit trigger and latching circuit.

[0015] Furthermore, the second short-circuit detection circuit includes a current detection device and a signal processing circuit, wherein the signal processing circuit includes any one or more of a decoupling diode, a voltage limiting device, an amplifying device, a comparator, a device, and a resistor.

[0016] Furthermore, the current sensing device is connected in the current path of the electronic switching circuit, and the signal processing circuit is configured to generate the second trigger signal based on the voltage on the current sensing device in response to the current in the current path exceeding a predetermined threshold.

[0017] Furthermore, the short-circuit triggering and latching circuit includes a trigger signal mixing circuit, a latching circuit, and one or more of the following: a power supply filtering device and a decoupling diode. A first trigger signal from the first short-circuit detection circuit and a second trigger signal from the second short-circuit detection circuit are mixed into a valid trigger signal by the trigger signal mixing circuit and transmitted to the latching circuit, causing the latching circuit to activate and shut down the electronic switch circuit. The short-circuit triggering and latching circuit allows external circuitry to reset and enable it, and provides a latched state to external circuitry.

[0018] Furthermore, the trigger signal mixing circuit includes one of an analog switch, an AND gate, and a NOR gate, and includes a resistor and a diode protection device. The trigger signal mixing circuit is configured to mix the received first trigger signal and the second trigger signal into a single valid trigger signal and then send it to the trigger circuit.

[0019] Furthermore, the latching circuit includes one or more of a trigger, an amplifying device, a resistive device, and a bypass capacitor. The latching circuit is configured to perform a latching action to turn off the electronic switching circuit upon receiving a trigger signal from the trigger signal mixing circuit, until the latching circuit is reset.

[0020] Compared with the prior art, the present invention has the following beneficial effects: The present invention not only protects the electronic switching device from damage by large current impact when the load is short-circuited, but also improves the anti-interference capability of the short-circuit protection circuit, making it less prone to malfunction, thereby improving the stability of the electronic switch. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the short-circuit protection circuit for the electronic switch of this utility model.

[0022] Figure 2 This is the overall circuit diagram of Embodiment 1 of this utility model;

[0023] Figure 3 This is the overall circuit diagram of Embodiment 2 of this utility model;

[0024] Figure 4 This is the overall circuit diagram of Embodiment 3 of this utility model;

[0025] Figure 5 This is the overall circuit diagram of Embodiment 4 of this utility model;

[0026] Figure 6 This is the overall circuit diagram of Embodiment 5 of this utility model;

[0027] Figure 7 This is the overall circuit diagram of Embodiment 6 of this utility model;

[0028] Figure 8 This is the overall circuit diagram of Embodiment 7 of this utility model. Detailed Implementation

[0029] To further illustrate the technical means and effects adopted by this utility model in order to achieve the intended utility model purpose, the following detailed description of the specific implementation methods, structure, features and effects of this utility model is provided in conjunction with the accompanying drawings and preferred embodiments.

[0030] Please see Figure 1 This embodiment provides an electronic switch short-circuit protection circuit, such as... Figure 1 As shown, it includes: an electronic switch circuit connected in series with the load to perform the switching action of the load, and also includes: a first short-circuit detection circuit, a second short-circuit detection circuit, and a short-circuit triggering and latching circuit connected to the electronic switch circuit.

[0031] When a short circuit occurs in the load of the electronic switch circuit, a short-circuit voltage is generated on the switching device of the electronic switch circuit and the current detection device of the second short-circuit detection circuit. The first short-circuit detection circuit converts the short-circuit voltage on the switching device of the electronic switch circuit into a first trigger signal for the short-circuit trigger and latching circuit. The second short-circuit detection circuit generates a second trigger signal required by the short-circuit trigger and latching circuit based on the short-circuit voltage on its current detection device, thereby shutting down the electronic switch circuit and performing short-circuit protection.

[0032] Example 1: As Figure 2 As shown, the electronic switch circuit includes a rectifier D9, a switch Q1, and a resistor R4. The AC2 input terminal of the rectifier D9 is connected to one end of the load, and the other end of the load is connected to the neutral line of the mains. The AC1 input terminal of the rectifier D9 is connected to the live line of the mains, realizing the series connection between the electronic switch circuit and the load. The V+ terminal of the rectifier D9 is connected to the drain 1 of the switch Q1, and is connected to the port 9 of the short-circuit first detection circuit through port 4. When a short circuit occurs in the load, the short-circuit voltage generated on the switch Q1 provides a first trigger signal to the short-circuit trigger and latching circuit through the short-circuit first detection circuit.

[0033] The gate 3 of the switching device Q1 is connected to one end of the resistor R4, and is connected to port 13 of the short-circuit trigger and latch circuit through port 5. When a short circuit occurs in the load, port 13 of the short-circuit trigger and latch circuit is pulled low, and the gate 3 of the switching device Q1 is pulled low, thereby turning off the switching device Q1, cutting off the main load circuit, and executing the short-circuit protection. The source 2 of the switching device Q1 is connected to port 6-2 of the second short-circuit detection circuit through port 3-2. The V- terminal of the rectifier D9 is connected to port 6-1 of the second short-circuit detection circuit through port 3-1, so that the current flowing through the switching device Q1 also flows through the second short-circuit detection circuit. When a short circuit occurs, the second short-circuit detection circuit provides a second trigger signal to the short-circuit trigger and latch circuit. The other end of the resistor R4 is connected to an external drive signal to prevent damage to the drive circuit when port 13 of the short-circuit trigger and latch circuit is pulled low, and also to make the turn-off of the switching device Q1 easier and more reliable.

[0034] The first short-circuit detection circuit includes capacitor C1, resistors R1 and R2, and Zener diode D6. One end of capacitor C1 is connected to one end of resistor R1, and is connected to port 4 of the electronic switch circuit through port 9 to obtain the short-circuit voltage generated on the switching device Q1 when a short circuit occurs in the load. The other end of capacitor C1 is connected to the other end of resistor R1, one end of resistor R2, and the cathode of Zener diode D6, and is connected to port 12 of the short-circuit trigger and latch circuit through port 11. The short-circuit voltage obtained from the switching device Q1 of the electronic switch circuit is accelerated by capacitor C1, divided by resistors R1 and R2, and limited by Zener diode D6, and converted into the first trigger signal required by the short-circuit trigger and latch circuit. The other end of resistor R2 is connected to the anode of Zener diode D6 as the common ground of the first short-circuit detection circuit, and is connected to the common ground port 8 of the second short-circuit detection circuit and the common ground port 15 of the short-circuit trigger and latch circuit through port 10.

[0035] The second short-circuit detection circuit includes a current-sensing resistor R6, a resistor R7, and a transistor Q4. One end of the current-sensing resistor R6 is connected to one end of the resistor R7, and then connected to port 3-2 of the electronic switch circuit via port 6-2, allowing the current flowing through the switching device Q1 to flow through the current-sensing resistor R6. When a short circuit occurs in the load, a short-circuit voltage is generated across the current-sensing resistor R6. The other end of the resistor R7 is connected to the base of the transistor Q4. The short-circuit voltage generated across the current-sensing resistor R6 drives the transistor Q4 to conduct through R7, thus turning on the collector of the transistor Q4. Port 7 is connected to port 14 of the short-circuit trigger and latch circuit. After the transistor Q4 is driven to conduct by the short-circuit voltage, it pulls port 7 low, generating the second trigger signal required by the short-circuit trigger and latch circuit. The other end of the current sensing resistor R6 is connected to the emitter of the transistor Q4 as the common ground of the second short-circuit detection circuit. It is connected to port 10 of the first short-circuit detection circuit and port 15 of the short-circuit trigger and latch circuit through port 8, and to port 3-1 of the electronic switch circuit through port 6-1, thus turning on the current sensing loop.

[0036] The short-circuit triggering and latching circuit includes an analog switch U1, a D flip-flop U2, a protection diode D3, a pull-up resistor R8, a capacitor C2, a resistor R9, and a transistor Q5.

[0037] The normally closed pin NC of analog switch U1 is connected to the anode of the input protection diode D3 as the input terminal of the first trigger signal, and is connected to port 11 of the short-circuit first detection circuit through port 12 to obtain the first trigger signal. The control input pin IN of analog switch U1 is connected to one end of the pull-up resistor R8, and is connected to port 7 of the short-circuit second detection circuit through port 14. When the load is short-circuited, the second trigger signal generated by the short-circuit second detection circuit pulls port 7 low, and the control input pin IN of analog switch U1 is pulled low. The switch common pin COM of analog switch U1 changes from a low-level state connected to the normally open pin NO to a state connected to the normally closed pin NC. If there is a high-level first trigger signal on the normally closed pin NC, the switch common pin COM outputs a high level, generating a trigger signal that changes from low level to high level on the switch common pin.

[0038] The common pin COM of analog switch U1 is connected to the trigger pin CP of D flip-flop U2. A trigger signal from low to high on the common pin COM triggers D flip-flop U2 through the trigger pin CP. The data input pin D of D flip-flop U2 is connected to the power supply pin Vcc of D flip-flop U2, the power supply pin V+ of analog switch U1, the other end of pull-up resistor R8, and the cathode of protection diode D3, and is also connected to an external power supply input. When D flip-flop U2 is triggered, its output pin Q outputs a high level. The output pin Q of D flip-flop U2 is connected to resistor R8. One end of resistor R9 is connected to one end of capacitor C2, and serves as a short-circuit signal output to indicate the short-circuit state to the external circuit. The other end of resistor R9 is connected to the other end of capacitor C2 and the base of transistor Q5. The high level output by pin Q of D flip-flop U2 drives transistor Q5 to conduct through resistor R9 and capacitor C2. The collector of transistor Q5 pulls port 13 low, turning off the switching device Q1 of the electronic switch circuit and performing short-circuit protection. The data clear pin MR of D flip-flop U2 is connected to an external short-circuit reset input, and the working state of the short-circuit trigger and latching circuit can be controlled by an external circuit.

[0039] The normally closed pin of analog switch U1 is connected to its ground pin GND, the ground pin GND of D flip-flop U2, and the emitter of transistor Q5 as the common ground of the short-circuit trigger and latching circuit. It is also connected to the common ground port 10 of the first short-circuit detection circuit and the common ground port 8 of the second short-circuit detection circuit through port 15.

[0040] Example 2: As Figure 3 As shown, the difference from Example 1 is that:

[0041] The electronic switching circuit includes a complementary switch composed of switching devices Q1 and Q2, power-collecting diodes D1 and D2, driving resistors R3 and R4, and diodes D4, D5, D7, and D8. The complementary switch composed of Q1 and Q2 replaces the rectifier Q9 and switching device Q1 in Example 1. The load is connected in series with Q1 and Q2 in the same circuit, and the driving signal drives Q2 and Q1 respectively through R3 and R4. Diodes D1 and D2 are connected to the drains of switching devices Q1 and Q2, respectively. When a short circuit occurs in the load, the short-circuit voltage generated on the drains of switching devices Q1 and Q2 is sent to the input port 9 of the first short-circuit detection circuit through port 4 via D1 and D2, causing the first short-circuit detection circuit to generate a first trigger signal. Switching devices Q1 and Q2 are three-terminal devices (drain 1, source 2, gate 3). The gate 3 of Q1 is connected to one end of resistor R4 and the anode of diode D4, and the gate 3 of Q2 is connected to one end of resistor R3 and the anode of diode D5. Diodes D4 and D5 are connected to their cathodes and are connected to port 13 of the short-circuit trigger and latch circuit through port 5. When a short circuit occurs in the load, port 13 of the short-circuit trigger and latch circuit is pulled low, causing the voltage at the gate 3 of switching devices Q1 and Q2 to drop, turning off Q1 and Q2, thereby disconnecting the main load circuit and achieving short-circuit protection. The source 2 of switching device Q1 is connected to port 6-2 of the second short-circuit detection circuit through port 3-2, and the source 2 of switching device Q2 is connected to port 6-1 of the second short-circuit detection circuit through port 3-1, ensuring that the current flowing through switching devices Q1 and Q2 flows through the second short-circuit detection circuit at the same time. When a short circuit occurs, the second short-circuit detection circuit detects the abnormal current and provides a second trigger signal to the short-circuit trigger and latching circuit. The cathodes of diodes D7 and D8 are connected to the drain 1 of switching devices Q1 and Q2, respectively, and the anodes of diodes D7 and D8 are connected to the source 2 of switching devices Q1 and Q2, respectively, so that alternating current can flow through the electronic switching circuit.

[0042] The other ends of resistors R3 and R4 are connected to an external drive signal to provide normal operation control signals for switching devices Q1 and Q2. When port 13 of the short-circuit trigger and latch circuit is pulled low, R3 and R4 protect the drive circuit and prevent damage to the drive signal. At the same time, due to the current limiting effect, the turn-off process of Q1 and Q2 is faster and more reliable.

[0043] The second short-circuit detection circuit includes current sensing resistors R6, R5, and R7, and transistors Q3 and Q4. Current sensing resistor R6 is connected in series in the electronic switching circuit to convert the load current into a voltage signal. The current flowing through current sensing resistor R6 is alternating current (AC), therefore, a short-circuit voltage detection circuit is configured at each end of current sensing resistor R6 to ensure that short-circuit currents in both directions can be detected. One short-circuit voltage detection circuit consists of resistor R7 and transistor Q4. When a short circuit occurs in the load and current flows in from port 6-2, the short-circuit voltage generated across current sensing resistor R6 drives transistor Q4 to conduct through R7, generating a second trigger signal. The other short-circuit voltage detection circuit consists of resistor R5 and transistor Q3. When a short circuit occurs in the load and current flows in from port 6-1, the short-circuit voltage generated across current sensing resistor R6 drives transistor Q3 to conduct through R3, generating a second trigger signal. The trigger signals generated by both short-circuit voltage detection circuits are transmitted through port 7 to the second trigger signal input port 14 of the short-circuit trigger and latch circuit.

[0044] Example 3: As Figure 4 As shown, the difference from Example 1 is that:

[0045] The second short-circuit detection circuit includes a fast comparator U3 (model TLV3201), a current sensing resistor R6, resistors (R10, R11, R16, R17), a Zener diode D10, and capacitors (C3, C5). Operational amplifier U3 is a fast comparator used for current signal comparison and triggering. Its non-inverting input (+) is connected to the voltage divider signal from resistors R10 and R11, its inverting input (-) is connected to a reference voltage, and its output is connected to port 7. The current sensing resistor R6 is connected in series between ports 6-1 and 6-2 for current sampling. When the load current flows through R6, a voltage signal is generated. After being divided by resistors R10 and R11 and limited by the Zener diode, the signal is input to the non-inverting input (+) of U3. Capacitor C3 is connected in parallel across the upper voltage divider resistor R10 to accelerate the transmission of the voltage signal across the current sensing resistor R6 to the non-inverting input (+) of the fast comparator U3. The reference voltage at the inverting input (-) of the fast comparator is obtained from the power supply through a voltage divider between resistors R16 and R17. Capacitor C5 is connected in parallel across the lower voltage divider resistor R17 to ensure a clean and stable reference voltage. When no short circuit occurs, the voltage at the non-inverting input (+) of the fast comparator U3 is lower than the voltage at the inverting input (-), resulting in a low output for the fast comparator U3 and a low output for port 7. When a short circuit occurs, the voltage at the non-inverting input (+) of the fast comparator U3 is higher than the voltage at the inverting input (-), resulting in a high output for the fast comparator U3 and a high-level second trigger signal output from port 7.

[0046] The first short-circuit detection circuit includes capacitors (C1, C6), resistors (R1, R2, R18, R19), a Zener diode D6, and a fast comparator U4 (model TLV3201). One end of capacitor C1 is connected to one end of resistor R1, and then connected to port 4 of the electronic switching circuit via port 9, used to acquire the short-circuit voltage generated on the switching devices (Q1, Q2) when a short circuit occurs in the load. The other ends of resistor R1, resistor R2, capacitor C1, and the cathode of Zener diode D6 are connected, and simultaneously connected to the positive input terminal (+) of fast comparator U4. One end of resistor R18 is connected to the positive power supply of fast comparator U4, and the other end is connected to one end of R19 and one end of capacitor C6, forming a voltage reference, which is connected to the negative input terminal (-) of fast comparator U4. The output terminal of fast comparator U4 is connected to port 12 of the short-circuit trigger and latch circuit via port 11. The above circuit converts the detected short-circuit voltage signal into the first trigger signal required by the short-circuit trigger and latch circuit. Capacitor C1 is connected in parallel across resistor R1 to accelerate the transmission of the short-circuit voltage signal to the positive input (+) of the fast comparator (U4). A Zener diode is connected in parallel across the positive input (+) of the fast comparator (U4) to limit the voltage signal input to the positive input (+) of the fast comparator (U4), preventing excessive short-circuit voltage from damaging the operational amplifier U4 and ensuring the reliability of the input signal. When no short circuit occurs, the voltage at the non-inverting input (+) of the fast comparator U4 is lower than the voltage at the inverting input (-), and the output of the fast comparator U4 is low, as is port 11. When a short circuit occurs, the voltage at the non-inverting input (+) of the fast comparator U4 is higher than the voltage at the inverting input (-), and the output of the fast comparator U4 is high, with port 11 outputting a high-level second trigger signal. The other end of resistor R2, the anode of Zener diode D6, the negative terminal of the power supply of fast comparator U4, the other end of capacitor C6, and the other end of resistor R19 are connected, and are connected to the common ground port 8 of the short-circuit second detection circuit and the common ground port 15 of the short-circuit trigger and latch circuit through port 10, forming the common ground of the short-circuit first detection circuit.

[0047] In the short-circuit triggering and latching circuit, an AND gate U1 (74LVC1G08Q) is used to replace the analog switch U1 in Example 1. After the electronic switch circuit is turned on, if no short circuit occurs, the trigger signals output by the first short-circuit detection circuit and the second short-circuit detection circuit through port 11 and port 7 respectively are both low level, making the input terminals A and B of the AND gate U1 both low level, and the output terminal Y of the AND gate U1 outputs a low level. When a short circuit occurs, the trigger signals output by the first short-circuit detection circuit and the second short-circuit detection circuit through port 11 and port 7 respectively become high level, making the input terminals A and B of the AND gate U1 both high level, and its output terminal changes from low level to high level, thereby obtaining a trigger signal that changes from low level to high level to trigger the D flip-flop to turn off the electronic switch circuit and latch the closed state.

[0048] Example 4: Figure 5 As shown, its difference from Example 1 is that:

[0049] The electronic switching circuit includes a complementary switch composed of switching devices Q1 and Q2, power-collecting diodes D1 and D2, driving resistors R3 and R4, and diodes D4, D5, D7, and D8. The complementary switch composed of Q1 and Q2 replaces the rectifier Q9 and switching device Q1 in Example 1. The load is connected in series with Q1 and Q2 in the same circuit, and the driving signal drives Q2 and Q1 respectively through R3 and R4. Diodes D1 and D2 are connected to the drains of switching devices Q1 and Q2, respectively. When a short circuit occurs in the load, the short-circuit voltage generated on the drains of switching devices Q1 and Q2 is sent to the input port 9 of the first short-circuit detection circuit through port 4 via D1 and D2, causing the first short-circuit detection circuit to generate a first trigger signal. Switching devices Q1 and Q2 are three-terminal devices (drain 1, source 2, gate 3). The gate 3 of Q1 is connected to one end of resistor R4 and the anode of diode D4, and the gate 3 of Q2 is connected to one end of resistor R3 and the anode of diode D5. Diodes D4 and D5 are connected to their cathodes and are connected to port 13 of the short-circuit trigger and latch circuit through port 5. When a short circuit occurs in the load, port 13 of the short-circuit trigger and latch circuit is pulled low, causing the voltage at the gate 3 of switching devices Q1 and Q2 to drop, turning off Q1 and Q2, thereby disconnecting the main load circuit and achieving short-circuit protection. The source 2 of switching device Q1 is connected to port 6-2 of the second short-circuit detection circuit through port 3-2, and the source 2 of switching device Q2 is connected to port 6-1 of the second short-circuit detection circuit through port 3-1, ensuring that the current flowing through switching devices Q1 and Q2 flows through the second short-circuit detection circuit at the same time; when a short circuit occurs, the second short-circuit detection circuit detects the abnormal current and provides a second trigger signal to the short-circuit trigger and latching circuit.

[0050] The other ends of resistors R3 and R4 are connected to an external drive signal to provide normal operation control signals for switching devices Q1 and Q2. When port 13 of the short-circuit trigger and latch circuit is pulled low, R3 and R4 protect the drive circuit and prevent damage to the drive signal. At the same time, due to the current limiting effect, the turn-off process of Q1 and Q2 is faster and more reliable.

[0051] The second short-circuit detection circuit uses dual current-sensing resistors (R6, R6-1) to detect bidirectional short-circuit current. It includes diodes (D11, D12), resistors (R10, R11), a capacitor (C3), and a Zener diode D10. One end of the current-sensing resistor R6 is connected to the anode of diode D11 and then to port 6-2 to detect the load circuit current flowing from port 6-2. One end of the current-sensing resistor R6-1 is connected to the anode of diode D12 and then to port 6-1 to detect the load circuit current flowing from port 6-1. The cathodes of diodes D11 and D12, one end of resistor R10, and one end of circuit C3 are connected. Regardless of which port the load circuit current flows from, its voltage across the two resistors is constant. When the voltage generated across the current sensing resistors (R6, R6-1) exceeds the forward voltage drop of the diodes (D11, D12), it is applied to one end of resistor R10 and one end of capacitor C3. The other end of resistor R10 is connected to the other end of capacitor C3, one end of resistor R11, and the cathode of Zener diode D0. The voltage applied to one end of resistor R10 and one end of capacitor C3 is accelerated by capacitor C3, divided by resistors R10 and R11, and limited by Zener diode D10, thus converting it into the second trigger signal required by the short-circuit trigger and latching circuit. The other end of current sensing resistor R6 is connected to the other end of current sensing resistor R6-1, the other end of resistor R11, and the anode of Zener diode D10 as the common ground of the second short-circuit detection circuit. It is connected to the common ground port 10 of the first short-circuit detection circuit and the common ground port 15 of the short-circuit trigger and latching circuit through port 8.

[0052] In the short-circuit triggering and latching circuit, an AND gate U1 (74LVC1G08Q) is used to replace the analog switch U1 in Example 1. After the electronic switch circuit is turned on, when no short circuit occurs, the trigger signals output by the first short-circuit detection circuit and the second short-circuit detection circuit through port 11 and port 7 respectively are both low level, making the input terminals A and B of the AND gate U1 both low level, and the output terminal Y of the AND gate U1 outputs a low level. When a short circuit occurs, the trigger signals output by the first short-circuit detection circuit and the second short-circuit detection circuit through port 11 and port 7 respectively become high level, making the input terminals A and B of the AND gate U1 both high level, and its output terminal changes from low level to high level, thereby obtaining a trigger signal that changes from low level to high level to trigger the D flip-flop to turn off the electronic switch circuit and latch the closed state.

[0053] Example 5: Figure 6As shown, its difference from Example 1 is that,

[0054] The electronic switching circuit includes a complementary switch composed of switching devices Q1 and Q2, power-collecting diodes D1 and D2, driving resistors R3 and R4, and diodes D4, D5, D7, and D8. The complementary switch composed of Q1 and Q2 replaces the rectifier Q9 and switching device Q1 in Example 1. The load is connected in series with Q1 and Q2 in the same circuit, and the driving signal drives Q2 and Q1 respectively through R3 and R4. Diodes D1 and D2 are connected to the drains of switching devices Q1 and Q2, respectively. When a short circuit occurs in the load, the short-circuit voltage generated on the drains of switching devices Q1 and Q2 is sent to the input port 9 of the first short-circuit detection circuit through port 4 via D1 and D2, causing the first short-circuit detection circuit to generate a first trigger signal. Switching devices Q1 and Q2 are three-terminal devices (drain 1, source 2, gate 3). The gate 3 of Q1 is connected to one end of resistor R4 and the anode of diode D4, and the gate 3 of Q2 is connected to one end of resistor R3 and the anode of diode D5. Diodes D4 and D5 are connected to their cathodes and are connected to port 13 of the short-circuit trigger and latch circuit through port 5. When a short circuit occurs in the load, port 13 of the short-circuit trigger and latch circuit is pulled low, causing the voltage at the gate 3 of switching devices Q1 and Q2 to drop, turning off Q1 and Q2, thereby disconnecting the main load circuit and achieving short-circuit protection. The source 2 of switching device Q1 is connected to port 6-2 of the second short-circuit detection circuit through port 3-2, and the source 2 of switching device Q2 is connected to port 6-1 of the second short-circuit detection circuit through port 3-1, ensuring that the current flowing through switching devices Q1 and Q2 flows through the second short-circuit detection circuit at the same time; when a short circuit occurs, the second short-circuit detection circuit detects the abnormal current and provides a second trigger signal to the short-circuit trigger and latching circuit.

[0055] The other ends of resistors R3 and R4 are connected to an external drive signal to provide normal operation control signals for switching devices Q1 and Q2. When port 13 of the short-circuit trigger and latch circuit is pulled low, R3 and R4 protect the drive circuit and prevent damage to the drive signal. At the same time, due to the current limiting effect, the turn-off process of Q1 and Q2 is faster and more reliable.

[0056] In the first short-circuit detection circuit, diode D6 is replaced with transistor Q6, and resistors R1 and R2 change from voltage divider to current limiter and shunt. When a short circuit occurs, the short-circuit voltage generated on the switching devices (Q1, Q2) is applied to the base of transistor Q6 through the current-limiting resistor R1, causing it to conduct and pull port 11 low. Resistor R2 shunts the current flowing into the base of transistor Q6, adjusting the input impedance of the base to improve stability and reliability, and also adjusting the detection sensitivity. Transistor Q6 can amplify small currents, resulting in higher sensitivity and making it suitable for weak signal detection.

[0057] A reverse current detection circuit is added to the second short-circuit detection circuit to ensure that both forward and reverse currents in the load circuit can be detected. This circuit includes resistor R5 and transistor Q3. One end of resistor R5 is connected to common ground; the emitter of transistor Q3 is connected to one end of current-sensing resistor R6 and port 6-2; the other end of resistor R5 is connected to the base of transistor Q3; and the collector of transistor Q3 is connected to port 7. When current flows into port 6-1, a voltage is generated at the common ground terminal of current-sensing resistor R6. This voltage drives transistor Q3 to conduct through resistor R5, pulling port 7 low and outputting the second trigger signal.

[0058] In the short-circuit triggering and latching circuit, a NOR gate U1 (74LVC1G02) is used to replace the analog switch U1 in Example 1. After the electronic switch circuit is turned on, when no short circuit occurs, ports 11 and 7 of the first short-circuit detection circuit and the second short-circuit detection circuit are in the released state. The two input terminals A and B of the NOR gate U1 are respectively set to a high level by the two pull-up resistors R12 and R8, and the output terminal Y of the NOR gate U1 outputs a low level. When a short circuit occurs, the first short-circuit detection circuit and the second short-circuit detection circuit pull down ports 11 and 7 respectively. The two input terminals A and B of the NOR gate U1 both become low level, and its output terminal changes from low level to high level, thereby obtaining a trigger signal that changes from low level to high level to trigger the D flip-flop to turn off the electronic switch circuit and latch the closed state.

[0059] Example 6: As Figure 7 As shown, the difference from Example 1 is that:

[0060] The electronic switching circuit includes a complementary switch composed of switching devices Q1 and Q2, power-collecting diodes D1 and D2, driving resistors R3 and R4, and diodes D4, D5, D7, and D8. The complementary switch composed of Q1 and Q2 replaces the rectifier Q9 and switching device Q1 in Example 1. The load is connected in series with Q1 and Q2 in the same circuit, and the driving signal drives Q2 and Q1 respectively through R3 and R4. Diodes D1 and D2 are connected to the drains of switching devices Q1 and Q2, respectively. When a short circuit occurs in the load, the short-circuit voltage generated on the drains of switching devices Q1 and Q2 is sent to the input port 9 of the first short-circuit detection circuit through port 4 via D1 and D2, causing the first short-circuit detection circuit to generate a first trigger signal. Switching devices Q1 and Q2 are three-terminal devices (drain 1, source 2, gate 3). The gate 3 of Q1 is connected to one end of resistor R4 and the anode of diode D4, and the gate 3 of Q2 is connected to one end of resistor R3 and the anode of diode D5. Diodes D4 and D5 are connected to their cathodes and are connected to port 13 of the short-circuit trigger and latch circuit through port 5. When a short circuit occurs in the load, port 13 of the short-circuit trigger and latch circuit is pulled low, causing the voltage at the gate 3 of switching devices Q1 and Q2 to drop, turning off Q1 and Q2, thereby disconnecting the main load circuit and achieving short-circuit protection. The source 2 of switching device Q1 is connected to port 6-2 of the second short-circuit detection circuit through port 3-2, and the source 2 of switching device Q2 is connected to port 6-1 of the second short-circuit detection circuit through port 3-1, ensuring that the current flowing through switching devices Q1 and Q2 flows through the second short-circuit detection circuit at the same time. When a short circuit occurs, the second short-circuit detection circuit detects the abnormal current and provides a second trigger signal to the short-circuit trigger and latching circuit. The cathodes of diodes D7 and D8 are connected to the drain 1 of switching devices Q1 and Q2, respectively, and the anodes of diodes D7 and D8 are connected to the source 2 of switching devices Q1 and Q2, respectively, so that alternating current can flow through the electronic switching circuit.

[0061] The other ends of resistors R3 and R4 are connected to an external drive signal to provide normal operation control signals for switching devices Q1 and Q2. When port 13 of the short-circuit trigger and latch circuit is pulled low, R3 and R4 protect the drive circuit and prevent damage to the drive signal. At the same time, due to the current limiting effect, the turn-off process of Q1 and Q2 is faster and more reliable.

[0062] In the first short-circuit detection circuit, diode D6 is replaced with transistor Q6, and resistors R1 and R2 change from voltage divider to current limiter and shunt. When a short circuit occurs, the short-circuit voltage generated on the switching devices (Q1, Q2) is applied to the base of transistor Q6 through the current-limiting resistor R1, causing it to conduct and pull port 11 low. Resistor R2 shunts the current flowing into the base of transistor Q6, adjusting the input impedance of the base to improve stability and reliability, and also adjusting the detection sensitivity. Transistor Q6 can amplify small currents, resulting in higher sensitivity and making it suitable for weak signal detection.

[0063] A reverse current detection circuit is added to the second short-circuit detection circuit to ensure that both forward and reverse currents in the load circuit can be detected. This circuit includes resistor R5 and transistor Q3. One end of resistor R5 is connected to common ground, and the other end is connected to the base of transistor Q3. The emitter of transistor Q3 is connected to one end of current-sensing resistor R6 and port 6-2; the other end of resistor R5 is connected to the base of transistor Q3; and the collector of transistor Q3 is connected to port 7. When current flows into port 6-1, a voltage is generated at the common ground terminal of current-sensing resistor R6. This voltage drives transistor Q3 to conduct through resistor R5, pulling port 7 low and outputting the second trigger signal.

[0064] The short-circuit triggering and latching circuit includes a NOR gate U1 (74LVC1G02), transistors (Q7, Q8), resistors (R8, R9, R12, R13, R14, R15), capacitors (C2, C4), diode D14, and Zener diode D13. One end of resistor R8 is connected to input terminal B of NOR gate U1, port 14, and one end of resistor R12 is connected to input terminal A of NOR gate U1, port 12. The other end of resistor R8 is connected to the other end of resistor R12 and the power supply terminal VCC of NOR gate U1. Resistors R8 and R12 provide pull-up functionality for the two input terminals of NOR gate U1, ensuring that the output terminal Y of NOR gate U1 outputs a low level under normal conditions. When the electronic switch circuit is turned on and no short circuit occurs, ports 11 and 7 of the first and second short circuit detection circuits are in the released state. The two input terminals A and B of the NOR gate U1 are respectively pulled up by the two pull-up resistors R12 and R8, and the output terminal Y of the NOR gate U1 outputs a low level. When a short circuit occurs, the first and second short circuit detection circuits pull ports 11 and 7 low, respectively. The two input terminals A and B of the NOR gate U1 both become low, and its output terminal changes from low to high, thus obtaining a trigger signal that changes from low to high. Transistor Q7 is PNP type, and transistor Q8 is NPN type. The collector of transistor Q7 is connected to the base of transistor Q8, one end of resistor R9, and one end of capacitor C2, and is connected to an external short-circuit reset input. The short-circuit reset input is normally in a high-impedance state and must be pulled low during reset. The base of transistor Q7 is connected to the collector of transistor Q8, one end of resistor R15, the cathode of diode D14, and port 13. The emitter of transistor Q7 is connected to one end of resistor R14. The other end of resistor R9 is connected to the other end of capacitor C2 and the output of NOR gate U1. Resistor R14... The other end is connected to the other end of resistor R15 and one end of resistor R13, and is connected to the external power supply input; the other end of resistor R13 is connected to one end of capacitor C4 and the cathode of Zener diode D13, and is connected to the power supply terminal Vcc of NOR gate U1; the power supply ground terminal GND of NOR gate U1 is connected to the transmitter of transistor Q8 to form the common ground of the short-circuit trigger and latch circuit, and is connected to the common ground port 10 of the first short-circuit detection circuit and the common ground port 8 of the second short-circuit detection circuit through port 15. The anode of diode D14 serves as the short-circuit signal output terminal. Under normal conditions, if the external circuit pulls up this short-circuit signal output terminal, it is in a high-level state. Under short-circuit latching state, it is pulled down by the forward voltage drop of transistor Q8 plus the forward voltage drop of diode D14.Transistors Q7 and Q8 form a self-latching circuit. When the output Y of the NOR gate U1 changes from low to high, the high-level signal drives transistor Q8 to conduct through resistor R9. When transistor Q8 conducts, it pulls down the base of transistor Q7, causing Q7 to conduct. The conduction of transistor Q7 provides a bias current to the base of transistor Q8, maintaining Q8's conduction. This latches the conduction state of the two transistors (Q7 and Q8). Even if the output Y of the NOR gate U1 changes from high to low, the two transistors (Q7 and Q8) remain in the conducting state until they are reset by the short-circuit reset input signal, at which point they turn off and exit the conduction latching state. After transistor Q8 conducts, it pulls port 13 low and maintains it, thereby turning off the switching devices (Q1 and Q2) of the electronic switching circuit to achieve short-circuit protection. Capacitor C2 is connected in parallel across resistor R9. Its function is to accelerate the transmission of the high-level signal output from the Y terminal of NOR gate U1 to the base of transistor Q8, shortening the short-circuit latching response time and improving the reliability of short-circuit protection. Resistor R13, capacitor C4, and Zener diode D13 constitute a resistor-stepped secondary power supply to power NOR gate U1.

[0065] Example 7: Figure 8 As shown, the difference from Example 1 is that:

[0066] The second short-circuit detection circuit includes a current-sensing resistor R6, voltage divider resistors R10 and R11, capacitor C3, and Zener diode D10. The current-sensing resistor R6 is connected in series between ports 6-1 and 6-2, directly detecting the load circuit current. One end of the voltage divider resistor R10 is connected to one end of R6, one end of capacitor C3, and port 6-2; the other end is connected to the cathode of Zener diode D10, one end of voltage divider resistor R11, the other end of capacitor C3, and port 7. The other end of the current-sensing resistor R6, the other end of voltage divider resistor R11, and the anode of Zener diode form the common ground of the second short-circuit detection circuit. This ground is connected to the common ground port 10 of the first short-circuit detection circuit and the common ground port 15 of the short-circuit trigger and latch circuit via port 8, and to port 3-1 of the electronic switch circuit via port 6-1, thus activating the current-sensing circuit. The current flowing into port 6-2 generates a voltage across the sensing resistor R6. This voltage signal is divided by voltage divider resistors R10 and R11 and used as the second trigger signal, provided to the short-circuit trigger and latch circuit via port 7. Capacitor C3 is connected in parallel across the upper voltage divider resistor R10 to accelerate the transmission of the voltage signal to port 7, thereby improving the response speed to the voltage signal. Zener diode is connected in parallel across the lower voltage divider resistor R11 to limit the voltage at port 7, preventing voltage overshoot from damaging the short-circuit trigger and latching circuit.

[0067] In the short-circuit triggering and latching circuit, an AND gate U1 (74LVC1G08Q) is used to replace the analog switch U1 in Example 1. After the electronic switch circuit is turned on, if no short circuit occurs, the trigger signals output by the first short-circuit detection circuit and the second short-circuit detection circuit through port 11 and port 7 respectively are both low level, making the input terminals A and B of the AND gate U1 both low level, and the output terminal Y of the AND gate U1 outputs a low level. When a short circuit occurs, the trigger signals output by the first short-circuit detection circuit and the second short-circuit detection circuit through port 11 and port 7 respectively become high level, making the input terminals A and B of the AND gate U1 both high level, and its output terminal changes from low level to high level, thereby obtaining a trigger signal that changes from low level to high level to trigger the D flip-flop to turn off the electronic switch circuit and latch the closed state.

[0068] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Although the present utility model has been disclosed above with reference to a preferred embodiment, it is not intended to limit the present utility model. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present utility model. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the scope of the present utility model shall still fall within the scope of the present utility model.

Claims

1. An electronic switch short-circuit protection circuit, comprising: An electronic switching circuit connected in series with a load and performing the switching action of the load, characterized in that it further includes: a first short-circuit detection circuit, a second short-circuit detection circuit, and a short-circuit triggering and latching circuit connected to the electronic switching circuit. The electronic switching circuit is configured to generate a first short-circuit voltage on the switching device of the electronic switching circuit in response to a short circuit occurring in the load. The short-circuit first detection circuit is configured to convert the first short-circuit voltage on the switching device of the electronic switching circuit into a first trigger signal for the short-circuit trigger and latching circuit. The short-circuit second detection circuit is configured to: generate a second short-circuit voltage on the current sensing device of the short-circuit second detection circuit in response to a short circuit in the load, and generate a second trigger signal required for the short-circuit trigger and latching circuit based on the second short-circuit voltage; The short-circuit triggering and latching circuit is configured to shut down the electronic switch circuit in response to receiving both the first trigger signal and the second trigger signal, in order to perform short-circuit protection.

2. The electronic switch short-circuit protection circuit according to claim 1, characterized in that, The electronic switching circuit uses a rectifier device (D9) plus a switching device (Q1) or a dual switching device (Q1, Q2) to perform the load switching operation. It includes a reverse freewheeling diode (D7, D8), a decoupling diode (D1, D2, D4, D5) connected in parallel to the switching device (Q1, Q2), and at least one resistor device (R3, R4).

3. The electronic switch short-circuit protection circuit according to claim 2, characterized in that, The second input terminal of the rectifier (D9) is connected to one end of the load, and the other end of the load is connected to the neutral line of the mains power. The first input terminal of the rectifier (D9) is connected to the live line of the mains power. The first output terminal of the rectifier (D9) is connected to the first current terminal of the switching device and to the input terminal of the first short-circuit detection circuit. The control terminal of the switching device is connected to the output terminal of the short-circuit trigger and latch circuit and is connected to the drive circuit through a resistor (R4). The second current terminal of the switching device is connected to the first port of the second short-circuit detection circuit, and the second output terminal of the rectifier is connected to the second port of the second short-circuit detection circuit.

4. The electronic switch short-circuit protection circuit according to claim 2, characterized in that, The dual switching devices (Q1, Q2) include switching device 1 and switching device 2. The first current terminal of switching device 1 is connected to the mains live wire, and its second current terminal is connected to the first port of the second short-circuit detection circuit. The first current terminal of switching device 2 is connected to one end of the load, and the other end of the load is connected to the mains neutral wire. The second current terminal of switching device 2 is connected to the second port of the second short-circuit detection circuit. The first current terminals of the dual switching devices (Q1, Q2) are respectively connected to the input terminal of the first short-circuit detection circuit through decoupling diodes (D2, D1). The control terminals of the dual switching devices (Q1, Q2) are respectively connected to the output terminal of the short-circuit trigger and latch circuit through decoupling diodes (D4, D5), and are respectively connected to the drive circuit through resistors (R4, R3). Two reverse freewheeling diodes (D7, D8) are respectively connected in parallel on the first and second current terminals of the dual switching devices (Q1, Q2).

5. The electronic switch short-circuit protection circuit according to claim 1, characterized in that, The short-circuit first detection circuit includes a short-circuit voltage sampling circuit and a voltage signal conversion circuit. When the voltage signal obtained by the short-circuit voltage sampling circuit meets the trigger signal requirements of the short-circuit trigger and latch circuit, the voltage signal conversion circuit is not needed, and it is directly used as the first trigger signal of the short-circuit trigger and latch circuit. If it does not meet the requirements, the voltage signal conversion circuit is needed to convert it into the first trigger signal required by the short-circuit trigger and latch circuit. The input terminal of the short-circuit first detection circuit is connected to the electronic switch circuit, and its output terminal is connected to the short-circuit trigger and latch circuit.

6. The electronic switch short-circuit protection circuit according to claim 5, characterized in that, The short-circuit voltage sampling circuit includes voltage divider resistors (R1, R2), a bypass capacitor (C2), and a voltage limiting device (D6). The short-circuit voltage sampling circuit divides the short-circuit voltage from the electronic switch circuit through the voltage divider resistors (R1, R2). A bypass capacitor (C1) is connected in parallel with the upper voltage divider resistor (R1) to improve the sampling speed; and a voltage limiting device (D6) is connected in parallel with the lower voltage divider resistor (R2) to protect the subsequent circuits.

7. The electronic switch short-circuit protection circuit according to claim 5, characterized in that, The voltage signal conversion circuit includes any one or more of an amplifier (Q6), a comparator (U4), a capacitor (C6), and resistors (R18, R19), and is configured to convert the voltage signal obtained by the short-circuit voltage sampling circuit into a first trigger signal required by the short-circuit trigger and latch circuit.

8. The electronic switch short-circuit protection circuit according to claim 1, characterized in that, The second short-circuit detection circuit includes a current detection device (R6) and a signal processing circuit. The signal processing circuit includes any one or more of the following: decoupling diodes (D11, D12), voltage limiting device (D10), amplifying device (Q3, Q4), comparator device (U3), capacitor device (C3, C5), and resistive device (R5, R7, R10, R11, R16, R17).

9. The electronic switch short-circuit protection circuit according to claim 8, characterized in that, The current sensing device (R6) is connected in the current path of the electronic switch circuit, and the signal processing circuit is configured to generate the second trigger signal based on the voltage on the current sensing device (R6) in response to the current in the current path exceeding a predetermined threshold.

10. The electronic switch short-circuit protection circuit according to claim 1, characterized in that, The short-circuit triggering and latching circuit includes a trigger signal mixing circuit, a latching circuit, and one or more of the following: power supply filtering devices (R13, C4, D13) and decoupling diode (D14). The first trigger signal from the first short-circuit detection circuit and the second trigger signal from the second short-circuit detection circuit are mixed into a valid trigger signal by the trigger signal mixing circuit and transmitted to the latching circuit, causing the latching circuit to operate and turn off the electronic switch circuit. The short-circuit triggering and latching circuit allows external circuits to reset and enable it, and provides a latched state to external circuits.

11. The electronic switch short-circuit protection circuit according to claim 10, characterized in that, The trigger signal mixing circuit includes one of an analog switch, an AND gate, or a NOR gate, and includes resistors (R8, R12) and diode protection devices (D3). The trigger signal mixing circuit is configured to mix the received first trigger signal and the second trigger signal into a valid trigger signal and send it to the latch circuit.

12. The electronic switch short-circuit protection circuit according to claim 10, characterized in that, The latching circuit includes one or more of a trigger (U2), an amplifier (Q5, Q7, Q8), a resistor (R9, R14, R15), and a bypass capacitor (C2). The latching circuit is configured to perform a latching action to turn off the electronic switch circuit after receiving a trigger signal from the trigger signal mixing circuit, until the latching circuit is reset.

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