Switching circuits and electric devices

Abstract

The present application discloses a switching circuit, including a control unit, a driving unit, a voltage mutation unit and a connecting unit. The connecting unit is electrically connected between a power supply device and a load device, and is used to conduct or disconnect the electrical connection between the power supply device and the load device. The control unit is electrically connected to the driving unit, and the driving unit is electrically connected to the connecting unit. The control unit is used to control the driving unit to output or stop outputting a driving signal for conducting the connecting unit to the connecting unit. The voltage mutation unit is electrically connected to a driving node between the driving unit and the connecting unit, and the control unit is electrically connected to the voltage mutation unit. The control unit is also used to control the voltage mutation unit to output a voltage mutation signal to the driving node, and the voltage mutation signal is used to quickly switch the connecting unit from conducting to cutting off when the driving unit stops outputting the driving signal. The present application also discloses an electric device, including a power supply device, a load device and the aforementioned switching circuit.

Description

Technical Field

[0001] The present application relates to the field of circuits, and in particular to a switch circuit and an electric device. Background Art

[0002] In the circuit design of electronic devices, a switch element is generally provided between the power supply end and the load end, and the electrical connection between the power supply end and the load end is achieved by turning on and off the switch element.

[0003] Common switching elements include transistors, such as MOS tubes. However, due to the instantaneous impact of the load current, the time it takes for the transistor to switch between the on and off states becomes longer, causing the transistor to operate in the linear region or burn out, thereby reducing the reliability of the entire electronic device. Summary of the invention

[0004] To solve the aforementioned problem, an embodiment of the present application provides a switching circuit, comprising a control unit, a driving unit, a voltage mutation unit and a connecting unit, wherein the connecting unit is electrically connected between a power supply device and a load device, and is used to conduct or disconnect the electrical connection between the power supply device and the load device; the control unit is electrically connected to the driving unit, and the driving unit is also electrically connected to the connecting unit, and the control unit is used to output an enable signal to the driving unit to control the driving unit to output or stop outputting a driving signal to the connecting unit, wherein the driving signal is used to conduct the connecting unit; the voltage mutation unit is electrically connected to a driving node between the driving unit and the connecting unit, and the control unit is also electrically connected to the voltage mutation unit, and the control unit is also used to output the enable signal to the voltage mutation unit to control the voltage mutation unit to generate and output a voltage mutation signal to the driving node, and the voltage mutation signal is used to control the potential of the driving node to mutate when the driving unit stops outputting the driving signal, so that the connecting unit quickly switches from an on state to an off state when no driving signal is received.

[0005] An embodiment of the present application provides an electric device, comprising a power supply device, a load device and the aforementioned switch circuit. The power supply device is electrically connected to the load device via the switch circuit, and is used to output a power signal to the load device when the switch circuit is in an on state. The load device is used to receive the power signal when the switch circuit is in an on state, and perform work according to the power signal.

[0006] Compared with the prior art, the voltage mutation unit used in the switch circuit disclosed in the embodiment of the present application can generate a voltage mutation signal to control the potential of the driving node to mutate when the driving unit stops outputting the driving signal that can turn on the connecting unit, so that the parasitic capacitance in the power MOS tube used by the connecting unit is quickly discharged to zero and the power MOS tube is quickly switched to the cut-off state, thereby preventing the power MOS tube from falling into the linear working area and being burned, thereby improving the reliability of the switch circuit during operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0008] Figure 1 A schematic diagram of the structure of an electric device disclosed in an embodiment of the present application;

[0009] Figure 2 for Figure 1 A schematic diagram of the structure of a switch circuit in the electric device shown;

[0010] Figure 3 for Figure 2 A structural schematic diagram of a specific circuit of the switching circuit shown. DETAILED DESCRIPTION

[0011] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0012] The following descriptions of the embodiments are with reference to the attached diagrams to illustrate specific embodiments in which the present invention can be implemented. The directional terms mentioned in the present invention, such as "upper", "lower", "front", "back", "left", "right", "inner", "outer", "side", etc., are only with reference to the directions of the attached diagrams. Therefore, the directional terms used are for better and clearer description and understanding of the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, or it can be detachably connected, or connected in one piece; it can be a mechanical connection; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0013] In this application, "of", "corresponding", "relevant" and "corresponding" can sometimes be used interchangeably. It should be noted that when the distinction is not emphasized, the meanings to be expressed are consistent. In addition, in order to facilitate the clear description of the technical solutions of the embodiments of the present application, in the embodiments of the present application, the words "first", "second" and the like are used to distinguish between identical or similar items with substantially the same functions and effects. Those skilled in the art will appreciate that the words "first", "second" and the like do not limit the quantity and order of execution, and the words "first", "second" and the like do not necessarily limit them to be different. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

[0014] See also Figure 1 , which is a schematic diagram of the structure of an electric device 10 disclosed in an embodiment of the present application. Figure 1 As shown, the electric device 10 includes a power supply device 100 , a switch circuit 200 and a load device 300 .

[0015] The power supply device 100 is electrically connected to the load device 300 via the switch circuit 200 , and is used to transmit the power signal to the load device 300 when the switch circuit 200 is in the on state.

[0016] In the embodiment of the present application, the power supply device 100 can be composed of a battery, which is a nickel-cadmium battery or a lithium polymer battery or other battery types that can provide a power signal to the load device 300, and the embodiment of the present application does not make specific limitations on this.

[0017] In the embodiment of the present application, the power supply device 100 can also be composed of a generator, which is supported by a combustible energy source. The combustible energy source includes natural or artificial fuels such as hydrogen, gasoline, and natural gas. The embodiment of the present application does not make any specific limitations on this.

[0018] In the embodiment of the present application, the power supply device 100 may also be composed of a battery and a generator at the same time, and the battery and the generator are used to provide a power signal to the load device 300.

[0019] The load device 300 is used to receive the power signal output by the power supply device, so as to drive the internal components to perform work according to the power signal.

[0020] In the embodiment of the present application, the load device 300 is a device that can perform work under the action of an electrical signal, and can be an electric ignition device or a drive motor or other electric drive device, which is not specifically limited in the embodiment of the present application.

[0021] The switch circuit 200 is electrically connected between the power supply device 100 and the load device 300, and is used to transmit the power signal output by the power supply device 100 to the load device 300 when in the on state, and is also used to stop transmitting the power signal output by the power supply device 100 to the load device 300 when in the off state.

[0022] In the embodiment of the present application, the electric device 10 provides a power signal to the load device 300 through the power supply device 100, and the load device 300 drives the electronic components inside it to work according to the power signal. At the same time, the switch circuit 200 provided between the power supply device 100 and the load device 300 can control the transmission of the power signal output by the power supply device 100 to realize power supply or power off to the load device 300.

[0023] See also Figure 2 , which is Figure 1 The schematic diagram of a switch circuit in an electric device is shown in FIG. Figure 2 As shown, the switch circuit 200 includes a control unit 201 , a driving unit 202 , a voltage mutation unit 203 and a connecting unit 204 .

[0024] The connection unit 204 is electrically connected between the power supply device 100 and the load device 300 , and is used to connect or disconnect the electrical connection between the power supply device 100 and the load device 300 .

[0025] The control unit 201 is electrically connected to the driving unit 202, and the driving unit 202 is also electrically connected to the connecting unit 204. The control unit 201 is used to output an enable signal to the driving unit 202 to control the driving unit 202 to output or stop outputting the driving signal to the connecting unit 204. The driving signal is used to turn on the connecting unit 204. The connecting unit 204 is in a conducting state when receiving the driving signal, and is in a cut-off state when not receiving the driving signal.

[0026] A driving node B is formed between the driving unit 202 and the connecting unit 204 , and the voltage mutation unit 203 is electrically connected to the driving node B.

[0027] The control unit 201 is also electrically connected to the voltage mutation unit 203, and is used to output the enable signal to the voltage mutation unit 203, so as to control the voltage mutation unit 203 to generate and output a voltage mutation signal to the driving node B. The voltage mutation signal is used to control the potential of the driving node B to mutate when the driving unit 202 stops outputting the driving signal, so that the connecting unit 204 can quickly switch from the on state to the off state when no driving signal is received.

[0028] In the prior art, the connection unit 204 is in the on state when receiving the driving signal, and is in the off state when not receiving the driving signal. However, the power MOS tube used by the connection unit 204 usually has parasitic capacitance. When the power MOS tube does not receive the driving signal, the residual charge in its parasitic capacitance causes the power MOS tube to remain in the on state until the residual charge is discharged to the point where the power MOS tube cannot be turned on. Therefore, when the driving unit 202 stops outputting the driving signal, the slow discharge of the parasitic capacitance causes the power MOS tube to operate in the linear region, which puts the power MOS tube at risk of burning out, and makes the connection unit 204 unable to switch to the off state, thereby making the switch circuit 200 unsafe and unreliable.

[0029] The voltage mutation unit 203 used in the switch circuit 200 of the present application can generate a voltage mutation signal to control the potential of the driving node B to mutate when the driving unit 202 stops outputting the driving signal, so that the parasitic capacitance in the power MOS tube used by the connecting unit 204 is quickly discharged to zero and the power MOS tube is quickly switched to the cut-off state, thereby preventing the power MOS tube from falling into the linear working area and being burned, thereby improving the reliability of the switch circuit 200 during operation.

[0030] In the embodiment of the present application, the control unit 201 can be a microcontroller unit (MCU) or a field programmable gate array (FPGA) or other integrated circuits that can control subsequent units, and the embodiment of the present application does not make specific limitations on this.

[0031] In an embodiment of the present application, the enable signal output by the control unit 201 includes a first voltage signal and a second voltage signal, wherein the first voltage signal is used to control the driving unit 202 to output a driving signal so that the connecting unit 204 enters an on state. At this time, the switching circuit 200 is in an on state, and the power supply device 100 and the load device 300 can be electrically connected via the switching circuit 200.

[0032] The second voltage signal is used to control the driving unit 202 to stop outputting the driving signal so that the connecting unit 204 enters the cut-off state, and at the same time controls the voltage mutation unit 203 to generate and output the voltage mutation signal, so as to control the potential of the driving node B to suddenly change when the driving unit 202 stops outputting the driving signal, so that the connecting unit 204 quickly switches from the on state to the off state. At this time, the switching circuit 200 is in the cut-off state, and the power supply device 100 and the load device 300 cannot be electrically connected through the switching circuit.

[0033] It is understandable that before the driving unit 202 stops outputting the driving signal, the potential of the driving node B is in a high level state due to receiving the driving signal. The control of the potential of the driving node B to change suddenly in the embodiment of the present application means that when the driving unit 202 stops outputting the driving signal, the voltage mutation unit 203 quickly pulls down the potential of the driving node B, that is, suddenly changes from a high level to a low level, so that the parasitic capacitance in the power MOS tube in the connecting unit 204 is quickly discharged to zero and the power MOS tube is quickly switched to the cut-off state, so that the connecting unit 204 can quickly enter the cut-off state.

[0034] See also Figure 3 , which is Figure 2 The schematic diagram of the specific circuit structure of the switch circuit is shown in FIG. Figure 3 As shown, the control unit 201 is electrically connected to the control node A, and is used to output an enable signal to the control node A, and then the control node A transmits the enable signal to the driving unit 202 and the voltage mutation unit 203.

[0035] Specifically, in this embodiment, the driving unit 202 includes a first input terminal IN1 , a first transistor Q1 , and a second transistor Q2 .

[0036] The first transistor Q1 is a P-type MOS transistor, and the second transistor Q2 is an NPN transistor.

[0037] The first input terminal IN1 is used to receive an input driving signal, the source of the first transistor Q1 is electrically connected to the first input terminal IN1, and the drain of the first transistor Q1 is electrically connected to the driving node B. The gate of the first transistor Q1 is electrically connected to the source of the first transistor Q1 through the first resistor R1, and is electrically connected to the collector of the second transistor Q2 through the second resistor R2.

[0038] The emitter of the second transistor Q2 is electrically connected to the ground terminal GND, and the base of the second transistor Q2 is electrically connected to the control node A.

[0039] In the embodiment of the present application, the second transistor Q2 in the driving unit 202 receives the enable signal transmitted by the control node A to achieve conduction or cutoff. Specifically, if the enable signal at the control node A is at a high level, the second transistor Q2 is turned on by the enable signal. At this time, the gate of the first transistor Q1 is electrically connected to the ground terminal GND through the second resistor R2 and the turned-on second transistor Q2, so that the gate level of the first transistor Q1 is pulled down, so that the first transistor Q1 is turned on, and the driving signal received by the first input terminal IN1 can be transmitted to the driving node B, thereby making the connection unit 204 in a conducting state; if the enable signal at the control node A is at a low level, the second transistor Q2 is cut off by the enable signal. At this time, the gate of the first transistor Q1 is connected to the first input terminal IN1 through the first resistor R1, so that the gate level of the first transistor Q1 is pulled up, so that the first transistor Q1 is cut off, so that the driving signal can no longer be transmitted to the driving node B through the second transistor Q2, and then the connection unit 204 is in a disconnected state.

[0040] The voltage mutation unit 203 includes a second input terminal IN2, a third transistor Q3, a first capacitor C1, a first voltage regulator diode D1 and a fourth transistor Q4.

[0041] The third transistor Q3 is an NPN transistor, and the fourth transistor Q4 is an N-type MOS transistor.

[0042] The second input terminal IN2 is electrically connected to the collector of the third transistor Q3 and the first capacitor node C of the first capacitor C1 through the third resistor R3. The second input terminal IN2 is used to receive an input charging voltage.

[0043] The second capacitor node D of the first capacitor C1 is electrically connected to the ground terminal GND through the fourth resistor R4.

[0044] The base of the third transistor Q3 is electrically connected to the control node A, the emitter of the third transistor Q3 is electrically connected to the ground terminal GND, and the collector of the third transistor Q3 is electrically connected to the first capacitor node C of the first capacitor C1.

[0045] An anode of the first diode D1 is electrically connected to the driving node B, and a cathode of the first diode D1 is electrically connected to a drain of the fourth transistor Q4 via a fifth resistor R5.

[0046] The gate of the fourth transistor Q4 is electrically connected to the second capacitor node D, and the source of the fourth transistor Q4 is electrically connected to the ground terminal GND. The gate of the fourth transistor Q4 is also electrically connected to the source of the fourth transistor Q4 through a fourth resistor R4.

[0047] In the embodiment of the present application, the third transistor Q3 in the voltage mutation unit 203 receives an enable signal transmitted by the control node A to achieve on or off. The fourth transistor Q4 is switched between on and off states by the potential of the second capacitor node D.

[0048] When in use, in the initial state, the control unit 201 outputs a low-level enable signal, the third transistor Q3 is turned off by the enable signal, the second input terminal IN2, the third resistor R3, the first capacitor C1, the fourth resistor R4 and the ground terminal GND form a current loop, so that the first capacitor C1 receives the charging voltage of the second input terminal IN2 and charges, at this time, the first capacitor node C is connected to the second input terminal IN2 through the third resistor R3, so that the potential at the first capacitor node C is in a high-level state due to the high-level signal input by the second input terminal IN2 and the maintenance of the first capacitor C1, and the second capacitor node D is electrically connected to the ground terminal GND through the fourth resistor R4, so that the second capacitor node D is in a low-level state, and the fourth transistor Q4 is turned off. It can be understood that after charging, the voltage difference between the two ends of the first capacitor C1 is relatively high.

[0049] At the beginning of the operation, when the control unit 201 outputs a high-level enable signal, as described above, the drive signal input by the first input terminal IN1 can be transmitted to the drive node B, that is, the drive node B is in a high-level state, and the connection unit 204 is in a conducting state. The third transistor Q3 is turned on by the enable signal, and the first capacitor node C is electrically connected to the ground terminal GND through the turned-on third transistor Q3, so that the potential of the first capacitor node C is suddenly changed from a high-level state to a low-level state. At this time, since the voltage difference between the two ends of the first capacitor C1 is relatively high, and the capacitance characteristics of the first capacitor C1 do not allow the voltage difference between its two ends to suddenly change, so that the potential at the second capacitor node D is suddenly changed from a low level to a high level state, so as to keep the voltage difference between the two ends of the first capacitor C1 unchanged, and the fourth transistor Q4 is turned on. Since the first capacitor C1 is electrically connected to the ground terminal GND through the fourth resistor R4 and gradually discharges, the potential at the second capacitor node D is gradually reduced. When the voltage at the second capacitor node D discharged from the first capacitor C1 is lower than the turn-on voltage Vgs (th) of the fourth transistor Q4, the fourth transistor Q4 is turned off.

[0050] It can be understood that after discharging, the voltage difference across the first capacitor C1 is relatively low.

[0051] It can be understood that during the period when the fourth transistor Q4 is turned on and off, the driving node B receives the driving voltage, and the connecting unit 204 remains in the on state.

[0052] When the control unit 201 outputs a low-level enable signal, as described above, the drive signal input by the first input terminal IN1 cannot be transmitted to the drive node B. The third transistor Q3 is cut off by the enable signal, the first capacitor node C is disconnected from the ground terminal GND, and the first capacitor node C is electrically connected to the second input terminal IN2 through the third resistor R3, so that the potential at the first capacitor node C suddenly changes from a low level to a high level state. At this time, since the voltage difference across the first capacitor C1 is low, and the capacitance characteristics of the first capacitor C1 do not allow the voltage difference across the first capacitor C1 to suddenly change, the potential at the second capacitor node D suddenly changes from a low level to a high level state, so as to keep the voltage difference across the first capacitor C1 unchanged, and the fourth transistor Q4 is turned on. The residual charge in the parasitic capacitance of the MOS tube in the connecting unit 204 is rapidly discharged through a loop formed by the driving node B, the first diode D1, the fifth resistor R5, the fourth transistor Q4 and the ground terminal GND, so that the residual charge of the MOS tube in the connecting unit 204 is rapidly returned to zero, so that the MOS tube in the connecting unit 204 is rapidly turned off, and the connecting unit 204 is rapidly switched from the on state to the off state.

[0053] It can be understood that, since the first capacitor C1 is electrically connected to the ground terminal GND through the fourth resistor R4 and gradually discharges, the potential at the second capacitor node D gradually decreases. When the voltage at the second capacitor node D discharged by the first capacitor C1 is lower than the turn-on voltage Vgs(th) of the fourth transistor Q4, the fourth transistor Q4 is turned off. After the fourth transistor Q4 is turned off, the driving node B does not receive the driving voltage, and the connecting unit 204 remains in the disconnected state.

[0054] The connection unit 204 includes a first connection terminal J1, a second connection terminal J2, a second diode D2, a third diode D3, and a plurality of connection sub-units.

[0055] The anode of the second diode D2 is electrically connected to the driving node B, and the cathode of the second diode D2 is electrically connected to the first connection terminal J1 through the sixth resistor R6. The first connection terminal J1 is used to connect one of the power supply device 100 and the load device 300.

[0056] An anode of the third diode D3 is electrically connected to the driving node B, and a cathode of the third diode D3 is electrically connected to the second connection terminal J2 through the seventh resistor R7. The second connection terminal J2 is used to connect the load device 300 and another device in the power supply device 100.

[0057] The structures of the multiple connecting subunits are similar. In the present application, one of the connecting subunits is taken as an example to introduce the structure of each connecting subunit in detail.

[0058] The connecting subunit includes a fifth transistor Q5 and a sixth transistor Q6, wherein the fifth transistor Q5 and the sixth transistor Q6 are both N-type transistors.

[0059] The gate of the fifth transistor Q5 is electrically connected to the driving node B through the eighth resistor R8, the source of the fifth transistor Q5 is electrically connected to the first connection terminal J1, and the drain of the fifth transistor Q5 is electrically connected to the transmission node E, and the transmission node E is used to transmit the electrical signal between the first connection terminal J1 and the second connection terminal J2.

[0060] The gate of the sixth transistor Q6 is electrically connected to the driving node B through the ninth resistor R9 , the source of the sixth transistor Q6 is electrically connected to the second connection terminal J2 , and the drain of the sixth transistor Q6 is electrically connected to the transmission node E.

[0061] In the embodiment of the present application, the connection unit 204 includes four connection subunits, and the four connection subunits work in parallel, that is, after one of the connection subunits is damaged, the other connection subunits can continue to work, and the current transmission capacity of the connection unit 204 can also be improved. It can be understood that the number of connection subunits in the connection unit 204 can be increased or decreased according to actual needs, and the embodiment of the present application does not specifically limit this.

[0062] In the embodiment of the present application, the MOS transistor in the connection unit 204 is switched between the on state and the off state by the potential signal at the driving node B. That is, in the initial state, the control unit 201 outputs a low-level enable signal, the first transistor Q1 is turned off by the enable signal, and the drive signal input by the first input terminal IN1 cannot be output to the MOS transistor in the connection unit 204 through the first transistor Q1, and the MOS transistor in the connection unit 204 is therefore in the off state. When starting to work, the control unit 201 outputs a high-level enable signal, the drive signal input by the first input terminal IN1 can be transmitted to the driving node B so that the driving node B is in a high-level state, the MOS transistor in the connection unit 204 is in the on state, and the power supply device 100 and the load device 300 electrically connected to the first connection terminal J1 and the second connection terminal J2 are electrically connected. When the work is finished, the control unit outputs a low-level enable signal, and the driving signal input by the first input terminal IN1 cannot be transmitted to the driving node B. The residual charge in the parasitic capacitance of the MOS tube in the connecting unit 204 is discharged to zero through the voltage mutation unit 203 electrically connected to the driving node B, so that the MOS tube in the output connecting unit 204 is quickly turned off, and the connecting unit 204 is quickly switched from the on state to the off state, and the power supply device 100 is electrically disconnected from the load device 300.

[0063] Compared with the prior art, the voltage mutation unit 203 used in the switch circuit 200 disclosed in the embodiment of the present application can generate a voltage mutation signal to control the potential of the driving node B to mutate when the driving unit 202 stops outputting the driving signal that can turn on the connecting unit 204, so that the parasitic capacitance in the power MOS tube used by the connecting unit 204 is quickly discharged to zero and the power MOS tube is quickly switched to the cut-off state, thereby preventing the power MOS tube from falling into the linear working area and being burned, thereby improving the reliability of the switch circuit 200 during operation.

[0064] A switching circuit and an electric device disclosed in an embodiment of the present application are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for a person skilled in the art, according to the idea of ​​the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A switching circuit, characterized in that: It includes a control unit, a driving unit, a voltage mutation unit and a connection unit, wherein: The connecting unit is electrically connected between the power supply device and the load device, and is used to conduct or disconnect the electrical connection between the power supply device and the load device, wherein the power supply device is composed of a battery and / or a generator; The control unit is electrically connected to the driving unit, and the driving unit is also electrically connected to the connecting unit. The control unit is used to output an enable signal to the driving unit to control the driving unit to output or stop outputting a driving signal to the connecting unit, wherein the driving signal is used to turn on the connecting unit; The voltage mutation unit is electrically connected to a driving node between the driving unit and the connecting unit, and the control unit is also electrically connected to the voltage mutation unit. The control unit is also used to output the enable signal to the voltage mutation unit to control the voltage mutation unit to generate and output a voltage mutation signal to the driving node. The voltage mutation signal is used to control the potential of the driving node to mutate when the driving unit stops outputting the driving signal, so that the connecting unit quickly switches from an on state to an off state when no driving signal is received.

2. The switch circuit according to claim 1, characterized in that: The enable signal includes a first voltage signal and a second voltage signal, wherein: The first voltage signal is used to control the driving unit to output the driving signal to the connecting unit, so that the connecting unit enters a conducting state; The second voltage signal is used to control the driving unit to stop outputting the driving signal, and is also used to control the voltage mutation unit to output a voltage mutation signal so that the potential of the driving node suddenly changes and the connecting unit enters a cut-off state.

3. The switch circuit according to claim 2, characterized in that: The driving unit includes a first input terminal, a first transistor and a second transistor, wherein: The gate of the first transistor is electrically connected to the source of the first transistor through a first resistor; The gate of the first transistor is also electrically connected to the collector of the second transistor through a second resistor, the source of the first transistor is also electrically connected to the first input terminal, the drain of the first transistor is electrically connected to the driving node, and the first input terminal is used to input a driving signal; The emitter of the second transistor is electrically connected to the ground terminal, the base of the second transistor is electrically connected to a control node, and the control node is electrically connected to the control unit for receiving an enable signal output by the control unit.

4. The switch circuit according to claim 3, characterized in that: The voltage mutation unit includes a second input terminal, a third transistor and a first capacitor, wherein: The second input terminal is electrically connected to the first capacitor node through a third resistor, and the first capacitor node is used to receive the charging voltage input by the second input terminal; The base of the third transistor is electrically connected to the control node, the emitter of the third transistor is electrically connected to the ground terminal, and the collector of the third transistor is electrically connected to the first capacitor node; The first capacitor is electrically connected between the first capacitor node and a second capacitor node, and a potential signal at the second capacitor node serves as a pull-down control signal.

5. The switch circuit according to claim 4, characterized in that: The voltage mutation unit further includes a first diode and a fourth transistor, wherein: The gate of the fourth transistor is electrically connected to the source of the fourth transistor through a fourth resistor; An anode of the first diode is electrically connected to the driving node, and a cathode of the first diode is electrically connected to a drain of the fourth transistor via a fifth resistor; The gate of the fourth transistor is electrically connected to the second capacitor node, and the source of the fourth transistor is electrically connected to the ground terminal.

6. The switch circuit according to claim 5, characterized in that: The connection unit includes a first connection terminal, a second connection terminal, a second diode, a third diode and at least one connection sub-unit, wherein: The anode of the second diode is electrically connected to the driving node, the cathode of the second diode is electrically connected to the first connection end through a sixth resistor, the first connection end is used to be electrically connected to a power supply device, and the power supply device is used to output a power signal; The anode of the third diode is electrically connected to the driving node, the cathode of the third diode is electrically connected to the second connection end through a seventh resistor, the second connection end is used to be electrically connected to a load device, and the load device is used to receive the power signal to perform work; The at least one connecting subunit is electrically connected between the first connecting end and the second connecting end.

7. The switch circuit according to claim 6, characterized in that: The at least one connecting subunit is switched between an on state and an off state under the action of the potential signal at the driving node.

8. The switch circuit according to claim 7, characterized in that: If the enable signal output by the control unit is the first voltage signal, the drive signal can be transmitted to the drive node to put the connection unit in an on state, the third transistor is turned on by the first voltage signal, the first capacitor node is electrically connected to the ground terminal through the turned-on third transistor, the potential at the second capacitor node suddenly changes to turn on the fourth transistor, and when the second capacitor node is discharged to the ground terminal through the fourth resistor to a voltage lower than the turn-on voltage of the fourth transistor, the fourth transistor is turned off.

9. The switch circuit according to claim 7, characterized in that: If the enable signal output by the control unit is the second voltage signal, the drive signal cannot be transmitted to the drive node, the third transistor is cut off by the second voltage signal, the first capacitor node is disconnected from the ground terminal, the second capacitor node is suddenly changed to turn on the fourth transistor, and the residual charge in the parasitic capacitance of the transistor in the connection unit is discharged to zero through the loop formed by the drive node, the first diode, the fifth resistor, the fourth transistor and the ground terminal, and the transistor in the connection unit is cut off.

10. An electric device, characterized in that: The invention comprises a power supply device, a load device and a switch circuit according to any one of claims 1 to 9, wherein: The power supply device is electrically connected to the load device via the switch circuit, and is used to output a power signal to the load device when the switch circuit is in an on state; The load device is used to receive the power signal when the switch circuit is in the on state, and perform work according to the power signal.

Images