CN215221825U

CN215221825U - Camera emergency management circuit and black box

Info

Publication number: CN215221825U
Application number: CN202120271062.1U
Authority: CN
Inventors: 玄先强; 郭雅芳; 陈浩; 程嘉俊; 闫天柱
Original assignee: Shenzhen Huigauss Technology Co ltd
Current assignee: Shenzhen Huigauss Technology Co ltd
Priority date: 2021-01-29
Filing date: 2021-01-29
Publication date: 2021-12-17
Anticipated expiration: 2031-01-29

Abstract

A camera emergency management circuit and a black box are provided, wherein the camera emergency management circuit adopts a camera, a control circuit, a power conversion circuit, an energy storage circuit and a power switching circuit, so that when external alternating current is normally supplied, the power conversion circuit converts the external alternating current into target direct current to supply power to the camera and the control circuit and charge the energy storage circuit; when external alternating current is cut off or cannot be input into the power conversion circuit due to reasons, the control circuit controls the power switching circuit to act, the camera and the control circuit are supplied with power through the energy storage circuit, normal work of the camera and the control circuit is maintained, the camera can be monitored normally, monitoring reliability is provided, and the problems that the traditional camera circuit cannot work normally when power is cut off and the monitoring reliability is poor are solved.

Description

Camera emergency management circuit and black box

Technical Field

The application belongs to the technical field of camera control, and particularly relates to an emergency management circuit of a camera and a black box.

Background

At present, a traditional camera circuit for monitoring is generally directly powered after commercial power is converted into direct current, but after power failure caused by an accident, the camera circuit cannot normally work, so that the field condition after the accident cannot be monitored, and the problems that the camera circuit cannot normally work in power failure and the monitoring reliability is poor exist.

Therefore, the traditional camera circuit has the problems that the normal work can not be realized in power failure and the monitoring reliability is poor.

SUMMERY OF THE UTILITY MODEL

The application aims to provide a camera emergency management circuit and a black box, and aims to solve the problems that a traditional camera circuit cannot work normally when power is cut off and the monitoring reliability is poor.

A first aspect of an embodiment of the present application provides a camera emergency management circuit, including:

the camera is used for acquiring images and converting the images into image signals;

a control circuit connected with the camera, the control circuit being configured to transmit the image signal to an external device;

the power supply conversion circuit is used for accessing external alternating current and converting the external alternating current into target direct current;

the energy storage circuit is connected with the power supply conversion circuit and is used for storing the target direct current; and

and the power supply switching circuit is connected with the power supply conversion circuit, the energy storage circuit, the control circuit and the camera, and is used for outputting the target direct current output by the power supply conversion circuit to the camera and the control circuit under the control of the control circuit and outputting the target direct current stored by the energy storage circuit to the camera and the control circuit when the power supply conversion circuit is powered off.

In one embodiment, the power conversion circuit includes:

the filter circuit is used for accessing the external alternating current and filtering out clutter interference of the external alternating current;

the rectifying circuit is connected with the filter circuit and is used for converting the external alternating current into direct current; and

and the DC-DC voltage conversion circuit is connected with the rectifying circuit, the energy storage circuit and the power supply switching circuit and is used for converting the direct current into target direct current.

In one embodiment, the power switching circuit includes: the input end of the first switch circuit is connected with the power conversion circuit, the input end of the second switch circuit is connected with the energy storage circuit, the output end of the first switch circuit and the output end of the second switch circuit are connected to the power supply end of the control circuit and the power supply end of the camera in a common mode, the control ends of the first switch circuit and the second switch circuit are connected with the control circuit, and the first switch circuit and the second switch circuit are alternately conducted under the control of the control circuit.

In one embodiment, the first switching circuit includes: a first switch tube, a second switch tube, a third switch tube, a first resistor, a second resistor, a third resistor and a first capacitor, the first end of the first resistor is connected with the first output end of the control circuit, the second end of the first resistor is connected with the control end of the first switch tube, the low potential end of the first switch tube is grounded, the high potential end of the first switch tube is connected with the first end of the second resistor, the second end of the second resistor is connected with the second end of the third resistor, the control end of the second switching tube and the control end of the third switching tube, the first end of the third resistor, the first end of the first capacitor, the high potential end of the second switching tube and the high potential end of the third switching tube are connected to the output end of the power conversion circuit in common, the low potential end of the second switching tube and the low potential end of the third switching tube are connected to the output end of the second switching circuit in a sharing mode.

In one embodiment, the power supply further comprises a voltage acquisition circuit, the voltage acquisition circuit is connected with the power conversion circuit and the control circuit, the voltage acquisition circuit is used for acquiring the voltage of the power conversion circuit and converting the voltage into a voltage detection signal to be output to the control circuit, and the control circuit is used for controlling the on-off of the first switch circuit and the second switch circuit according to the voltage detection signal.

In one embodiment, the direct current power supply further comprises a voltage stabilizing circuit, wherein the voltage stabilizing circuit is connected with the output end of the power supply switching circuit and is used for stabilizing the target direct current output by the power supply switching circuit into a target voltage and then outputting the target voltage.

In one embodiment, the camera further comprises an image storage circuit, wherein the image storage circuit is connected with the camera, the control circuit and the power supply switching circuit, and is used for starting when the power supply switching circuit is powered off so as to store image signals output by the camera.

In one embodiment, the display device further comprises a wireless communication circuit connected with the control circuit, the wireless communication circuit being used for transmitting the image signal to the external device.

In one embodiment, further comprising:

the driving circuit is connected with the control circuit and the power switching circuit and is used for outputting a driving signal when the power switching circuit is powered off; and

and the lighting circuit is connected with the driving circuit and is used for emitting light under the driving of the driving signal so as to provide emergency lighting.

A second aspect of an embodiment of the present application provides a black box, including the camera emergency management circuit according to the first aspect of an embodiment of the present application.

According to the camera emergency management circuit, the camera, the control circuit, the power conversion circuit, the energy storage circuit and the power switching circuit are adopted, so that when external alternating current is normally supplied, the power conversion circuit converts the external alternating current into target direct current to supply power to the camera and the control circuit and charge the energy storage circuit; when external alternating current is cut off or cannot be input into the power conversion circuit due to reasons, the control circuit controls the power switching circuit to act, the camera and the control circuit are supplied with power through the energy storage circuit, normal work of the camera and the control circuit is maintained, the camera can be monitored normally, monitoring reliability is provided, and the problems that the traditional camera circuit cannot work normally when power is cut off and the monitoring reliability is poor are solved.

Drawings

Fig. 1 is a schematic circuit diagram of a camera emergency management circuit according to an embodiment of the present disclosure;

FIG. 2 is a schematic circuit diagram of a power conversion circuit in the emergency management circuit of the camera shown in FIG. 1;

FIG. 3 is an exemplary circuit schematic of the power conversion circuit shown in FIG. 2;

fig. 4 is a schematic circuit diagram of a power switching circuit in the emergency management circuit of the camera shown in fig. 1;

FIG. 5 is an exemplary circuit schematic of the power switching circuit shown in FIG. 3;

FIG. 6 is another circuit schematic of the camera emergency management circuit of FIG. 4;

FIG. 7 is another circuit schematic of the camera emergency management circuit of FIG. 1;

FIG. 8 is another circuit schematic of the camera emergency management circuit of FIG. 1;

FIG. 9 is another circuit schematic of the camera emergency management circuit of FIG. 1;

fig. 10 is an exemplary circuit schematic of the drive circuit shown in fig. 9.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present application clearer, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.

It will be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like, refer to an orientation or positional relationship illustrated in the drawings for convenience in describing the present application and to simplify description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present application.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

Fig. 1 shows a circuit schematic diagram of a camera emergency management circuit 10 provided in a first aspect of an embodiment of the present application, and for convenience of description, only parts related to the embodiment are shown, which are detailed as follows:

the emergency management circuit 10 of the camera in this embodiment includes: the camera 100, the control circuit 200, the power conversion circuit 300, the tank circuit 400, and the power switching circuit 500. The data output terminal of the camera 100 is connected to the first input terminal of the control circuit 200, the first input terminal of the power switching circuit 500 is connected to the output terminal of the power conversion circuit 300, the second input terminal of the power switching circuit 500 is connected to the tank circuit 400, the output terminal of the power conversion circuit 300 is further connected to the tank circuit 400, the output terminal of the power switching circuit 500 is connected to the power source terminal of the control circuit 200 and the power source terminal of the camera 100, and the control terminal of the power switching circuit 500 is connected to the second output terminal of the control circuit 200. The camera 100 is used to capture images and convert the images into image signals. The control circuit 200 serves to transmit the image signal to the external device 20. The power conversion circuit 300 is used for receiving external alternating current and converting the external alternating current into target direct current. The tank circuit 400 is used to store the target dc power. The power supply switching circuit 500 is used for outputting the target direct current output from the power supply conversion circuit 300 to the video camera 100 and the control circuit 200 under the control of the control circuit 200, and for outputting the target direct current stored in the tank circuit 400 to the video camera 100 and the control circuit 200 when the power supply conversion circuit 300 is powered off.

It can be understood that the control circuit 200 may be formed by a microprocessor such as an image sensing chip, a single chip, or the like. The power conversion circuit 300 may be composed of a rectifier bridge, a voltage conversion chip, and the like. The energy storage circuit 400 may be formed by a device having an electric energy storage, such as an energy storage battery, an energy storage capacitor, and the like. The power switching circuit 500 may be formed by a plurality of controllable switching devices or a multiplexer. The external alternating current can be commercial power or alternating current output by an external alternating current power supply.

It is understood that, in the emergency management circuit 10 of the camera in this embodiment, when the power conversion circuit 300 is powered, i.e. when the external ac power is normally input to the power conversion circuit 300, the target dc power output by the power conversion circuit 300 charges the energy storage circuit 400 and supplies power to the camera 100 and the control circuit 200 through the power switching circuit 500. When the film conversion circuit is powered off, i.e. when the external ac power is off, the power switching circuit 500 switches the connection with the power conversion circuit 300 to the connection with the energy storage circuit 400, and the energy storage circuit 400 supplies power to the camera 100 and the control circuit 200.

In the emergency management circuit 10 of the camera in this embodiment, by using the camera 100, the control circuit 200, the power conversion circuit 300, the energy storage circuit 400 and the power switching circuit 500, when the external alternating current is normally supplied, the power conversion circuit 300 converts the external alternating current into the target direct current to supply power to the camera 100 and the control circuit 200, and charges the energy storage circuit 400; when the external ac power is cut off or cannot be input to the power conversion circuit 300 due to reasons, the control circuit 200 controls the power switching circuit 500 to operate, so that the energy storage circuit 400 supplies power to the camera 100 and the control circuit 200, thereby maintaining the normal operation of the camera 100 and the control circuit 200, enabling the camera 100 to monitor normally, providing monitoring reliability, and solving the problems that the conventional camera 100 cannot work normally when power is cut off and the monitoring reliability is poor.

Referring to fig. 2, in one embodiment, the power conversion circuit 300 includes: a filter circuit 310, a rectifier circuit 320, and a DC-DC voltage conversion circuit 330. The input end of the filter circuit 310 is used for receiving external alternating current, the output end of the filter circuit 310 is connected with the input end of the rectifying circuit 320, the output end of the rectifying circuit 320 is connected with the input end of the DC-DC voltage conversion circuit 330, and the output end of the DC-DC voltage conversion circuit 330 is connected with the power supply switching circuit 500 and the energy storage circuit 400. The filter circuit 310 is used for filtering out noise interference of the external alternating current. The rectifying circuit 320 is used to convert an external alternating current into a direct current. The DC-DC voltage conversion circuit 330 is used to convert the direct current into a target direct current.

It is understood that, referring to fig. 3, the filter circuit 310 may be formed by a filter capacitor, a resistor, a common mode inductor, and the like. The rectifying circuit 320 may be formed of a rectifying bridge or a rectifying chip or the like. The DC-DC voltage conversion circuit 330 may be constituted by a transformer.

In the power conversion circuit 300 in this embodiment, the filtering circuit 310, the rectifying circuit 320, and the DC-DC voltage conversion circuit 330 are used to implement filtering, rectifying, and voltage conversion on the external alternating current, so as to obtain the target direct current without clutter interference.

Referring to fig. 4, in one embodiment, the power switching circuit 500 includes: the input end of the first switch circuit 510 is connected with the power conversion circuit 300, the input end of the second switch circuit 520 is connected with the energy storage circuit 400, the output end of the first switch circuit 510 and the output end of the second switch circuit 520 are connected with the power supply end of the control circuit 200 and the power supply end of the camera 100, the control ends of the first switch circuit 510 and the second switch circuit 520 are connected with the control circuit 200, and the first switch circuit 510 and the second switch circuit 520 are alternately conducted under the control of the control circuit 200.

It is understood that the first switch circuit 510 and the second switch circuit 520 may be respectively formed by controllable electronic switches, such as transistors, MOS transistors, and the like.

It can be understood that when the power conversion circuit 300 has an output, i.e. when the power conversion circuit 300 normally accesses the external ac power, the control circuit 200 controls the first switch circuit 510 to be turned on, and at this time, only the power conversion circuit 300 supplies power to the video camera 100 and the control circuit 200 by the external ac power; when the power conversion circuit 300 has no output, i.e. when the power conversion circuit 300 cannot access external ac power or the voltage of the external ac power is zero, the control circuit 200 controls the second switch circuit 520 to be turned on, and at this time, only the power conversion circuit 300 is powered by the external ac power to the video camera 100 and the control circuit 200.

In the power switching circuit 500 in this embodiment, the first switch circuit 510 and the second switch circuit 520 are adopted, and the control circuit 200 is used to control the first switch circuit 510 and the second switch circuit 520 to be alternately turned on, so that the camera 100 and the control circuit 200 are supplied with power uninterruptedly, and power failure caused by accidents or other reasons is avoided, so that the camera 100 and the control circuit 200 do not have power supply and cannot work normally.

Referring to fig. 5, in one embodiment, the first switch circuit 510 includes: a first switch tube Q1, a second switch tube Q2, a third switch tube Q3, a first resistor R1, a second resistor R2, a third resistor R3 and a first capacitor C1, wherein a first terminal of the first resistor R1 is connected to the first output terminal of the control circuit 200, a second terminal of the first resistor R1 is connected to the control terminal of the first switch transistor Q1, a low potential terminal of the first switch transistor Q1 is grounded, a high potential terminal of the first switch transistor Q1 is connected to the first terminal of the second resistor R2, a second terminal of the second resistor R2 is connected to the second terminal of the third resistor R3, a control terminal of the second switch transistor Q2 and a control terminal of the third switch transistor Q3, a first terminal of the third resistor R3, a first terminal of the first capacitor C1, a high potential terminal of the second switch transistor Q2 and a high potential terminal of the third switch transistor Q3 are connected to the output terminal of the power conversion circuit 300, and a low potential terminal of the second switch transistor Q2 and a low potential terminal of the third switch transistor Q3 are connected to the output terminal of the second switch circuit 520.

It can be understood that the first switching tube Q1, the second switching tube Q2, and the third switching tube Q3 in this embodiment may be switching tubes such as a triode, a MOS tube, and the like. In this embodiment, the second switching tube Q2 and the third switching tube Q3 are connected in parallel, and are used as a redundant structure of power output, so as to avoid the situation that normal output cannot be performed due to the damage of the switching tubes.

Optionally, in this embodiment, the first switching tube Q1 is an NMOS tube, the second switching tube Q2 is a PMOS tube, and the third switching tube Q3 is a PMOS tube; the grid electrode of the NMOS tube is a control end, the drain electrode of the NMOS tube is a high potential end, and the source electrode of the NMOS tube is a low potential end; the grid electrode of the PMOS tube is a control end, the drain electrode of the PMOS tube is a low potential end, and the source electrode of the PMOS tube is a high potential end. When the control circuit 200 outputs a high level to the first switch transistor Q1, the first switch transistor Q1 is turned on, the second switch transistor Q2 is a PMOS transistor, the third switch transistor Q3 is a PMOS transistor, and the first switch circuit 510 is turned off. When the control circuit 200 outputs a low level to the first switch Q1, the first switch Q1 is turned off, the second switch Q2 is a PMOS transistor, the third switch Q3 is a PMOS transistor, and the first switch circuit 510 is turned on. In other embodiments, other switch tube combinations may be used.

It is understood that the composition of the second switching circuit 520 may refer to the first switching circuit 510.

Referring to fig. 6, in an embodiment, the camera emergency management circuit 10 further includes a voltage acquisition circuit 610, the voltage acquisition circuit 610 is connected to the power conversion circuit 300 and the control circuit 200, the voltage acquisition circuit 610 is configured to acquire a voltage of the power conversion circuit 300 and convert the voltage into a voltage detection signal to output to the control circuit 200, and the control circuit 200 is configured to control the on/off of the first switch circuit 510 and the second switch circuit 520 according to the voltage detection signal.

It is understood that the voltage acquisition circuit 610 may be comprised of a sampling resistor or a voltage sensor. The control circuit 200 determines whether the power conversion circuit 300 normally outputs the target dc power according to the magnitude of the voltage detection signal, and accordingly controls the on/off of the first switch circuit 510 and the second switch circuit 520. For example, when the voltage detection signal indicates that the output of the power conversion circuit 300 is normal, the control circuit 200 controls the first switch circuit 510 to be closed and the second switch circuit 520 to be opened. When the voltage detection signal indicates that the power conversion circuit 300 outputs an abnormal or no output, the control circuit 200 controls the first switch circuit 510 to be opened and the second switch circuit 520 to be closed. Thereby ensuring uninterrupted power supply to the camera 100 and the control circuit 200 and avoiding the occurrence of short circuit of the camera 100 and the control circuit 200 due to abnormal power supply voltage.

Referring to fig. 7, in an embodiment, the camera emergency management circuit 10 further includes a voltage stabilizing circuit 620, where the voltage stabilizing circuit 620 is connected to the output end of the power switching circuit 500, and is configured to stabilize the target dc output by the power switching circuit 500 to a target voltage and output the target dc.

It will be appreciated that the voltage regulation circuit 620 may be formed of a voltage regulation device or chip, such as a forward LDO model AMS 117. The voltage regulator circuit 620 may employ a plurality of voltage regulators with different voltage output values, so as to satisfy different power supply voltage requirements of the camera 100 and the control circuit 200.

Referring to fig. 7, in an embodiment, the camera emergency management circuit 10 further includes an image storage circuit 700, the image storage circuit 700 is connected to the camera 100, the control circuit 200 and the power switching circuit 500, and the image storage circuit 700 is configured to be activated when the power switching circuit 300 is powered off to store the image signal output by the camera 100.

It is understood that the image storage circuit 700 is used to store the image signal in the power-off state, and the image signal stored in the image storage circuit 700 can be output to the external device 20 through the control circuit 200. The image storage circuit 700 may also be used to store full-time image signals, including image signals in the non-powered-off condition. The camera emergency management circuit 10 in this embodiment protects the image signal acquired by the camera 100, prevents the image signal acquired by the camera 100 from being lost, and ensures the integrity of the image pickup data after special conditions such as an accident.

Referring to fig. 8, in one embodiment, the camera emergency management circuit 10 further includes a wireless communication circuit 800, the wireless communication circuit 800 is connected to the control circuit 200, and the wireless communication circuit 800 is configured to transmit the image signal to the external device 20.

It is understood that the external device 20 includes a cloud, or a user terminal such as a computer or a mobile phone. The wireless communication circuit 800 may be formed of a WIFI chip, a bluetooth chip, a radio frequency chip, and the like. If the image data needs to be retrieved, the data stored in the control circuit 200 or the image storage circuit 700 can be retrieved through the one-to-one connection of the wireless communication circuit 800. The situation that the image signal acquired by the camera 100 cannot be normally called due to the fact that the equipment for accommodating the camera emergency management circuit 10 cannot be opened by the traditional process under special conditions such as accidents is avoided.

Referring to fig. 9, in an embodiment, the camera emergency management circuit 10 further includes: the driving circuit 910 and the lighting circuit 920, wherein the input terminal of the driving circuit 910 is connected to the output terminal of the power switching circuit 500, the control terminal of the driving circuit 910 is connected to the control circuit 200, and the output terminal of the driving circuit 910 is connected to the lighting circuit 920. The driving circuit 910 is configured to output a driving signal when the power conversion circuit 300 is powered off. The lighting circuit 920 is used to emit light under the driving of the driving signal to provide emergency lighting.

It is understood that the driving circuit 910 may be formed by a switching circuit or an LED driving chip, for example, as shown in fig. 10, the driving circuit 910 is formed by a plurality of switching tubes, resistors, capacitors, and the like. The illumination circuit 920 is composed of a plurality of light emitting diodes.

The emergency management circuit 10 of the camera in this embodiment adopts the lighting circuit 920 as emergency lighting for indicating light for alarming an accident, and the light emitting devices in the lighting circuit 920 can be arranged at intervals from the position of the camera 100 to the exit position of the safe passage, so as to conveniently guide a route for people to escape in an emergency.

A second aspect of an embodiment of the present application provides a black box, including the camera emergency management circuit 10 according to the first aspect of an embodiment of the present application.

It can be understood that, in the black box of the present embodiment, when the external ac power is normally supplied, the external ac power is relied on to supply the power conversion circuit 300, on one hand, to charge the energy storage circuit 400, and on the other hand, to supply the power switching circuit 500, so as to supply power to the whole black box. When the power is suddenly cut off due to special conditions, the power supply switching circuit 500 automatically switches to the energy storage circuit 400 to start supplying power to the system. The image storage circuit 700 is used to store the video data under the power-off condition, and if the data needs to be retrieved, the stored data can be retrieved through one-to-one connection of the wireless communication circuit. The lighting circuit 920 may be used as emergency lighting, to provide alarm indications and to facilitate routing of personnel for escape in case of an emergency. The black box in the embodiment gives consideration to fire emergency escape guidance and investigation and evidence obtaining of sudden accidents. The device can still stably work in the middle of accidents such as fire and the like, and can ensure the integrity of data in the black box after fire fighting. The storage of the video data reserves sufficient evidence for the reason of the accident after the accident, and can provide necessary help for the follow-up accident investigation.

It will be apparent to those skilled in the art that, for convenience and brevity of description, only the above-mentioned division of the functional units and modules is illustrated, and in practical applications, the above-mentioned function distribution may be performed by different functional units and modules according to needs, that is, the internal structure of the apparatus is divided into different functional units or modules to perform all or part of the above-mentioned functions. Each functional unit and module in the embodiments may be integrated in one processing unit, or each unit may exist alone physically, or two or more units are integrated in one unit, and the integrated unit may be implemented in a form of hardware, or in a form of software functional unit. In addition, specific names of the functional units and modules are only for convenience of distinguishing from each other, and are not used for limiting the protection scope of the present application.

In the above embodiments, the descriptions of the respective embodiments have respective emphasis, and reference may be made to the related descriptions of other embodiments for parts that are not described or illustrated in a certain embodiment.

The above-mentioned embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.

Claims

1. A camera emergency management circuit, comprising:

2. The camera emergency management circuit of claim 1, wherein the power conversion circuit comprises:

3. The camera emergency management circuit of claim 1, wherein the power switching circuit comprises: the input end of the first switch circuit is connected with the power conversion circuit, the input end of the second switch circuit is connected with the energy storage circuit, the output end of the first switch circuit and the output end of the second switch circuit are connected to the power supply end of the control circuit and the power supply end of the camera in a common mode, the control ends of the first switch circuit and the second switch circuit are connected with the control circuit, and the first switch circuit and the second switch circuit are alternately conducted under the control of the control circuit.

4. The camera emergency management circuit of claim 3, wherein the first switching circuit comprises: a first switch tube, a second switch tube, a third switch tube, a first resistor, a second resistor, a third resistor and a first capacitor, the first end of the first resistor is connected with the first output end of the control circuit, the second end of the first resistor is connected with the control end of the first switch tube, the low potential end of the first switch tube is grounded, the high potential end of the first switch tube is connected with the first end of the second resistor, the second end of the second resistor is connected with the second end of the third resistor, the control end of the second switching tube and the control end of the third switching tube, the first end of the third resistor, the first end of the first capacitor, the high potential end of the second switching tube and the high potential end of the third switching tube are connected to the output end of the power conversion circuit in common, the low potential end of the second switching tube and the low potential end of the third switching tube are connected to the output end of the second switching circuit in a sharing mode.

5. The camera emergency management circuit according to claim 3, further comprising a voltage acquisition circuit, wherein the voltage acquisition circuit is connected to the power conversion circuit and the control circuit, the voltage acquisition circuit is configured to acquire a voltage of the power conversion circuit and convert the voltage into a voltage detection signal to output to the control circuit, and the control circuit is configured to control the first switch circuit and the second switch circuit to be turned on or off according to the voltage detection signal.

6. The camera emergency management circuit according to any one of claims 1 to 5, further comprising a voltage stabilizing circuit, connected to an output terminal of the power switching circuit, for stabilizing a target direct current output by the power switching circuit to a target voltage and outputting the target direct current.

7. The camera emergency management circuit according to any one of claims 1 to 5, further comprising an image storage circuit, wherein the image storage circuit is connected to the camera, the control circuit and the power switching circuit, and is configured to be activated when the power switching circuit is powered off to store an image signal output by the camera.

8. The camera emergency management circuit according to any one of claims 1 to 5, further comprising a wireless communication circuit connected to the control circuit, the wireless communication circuit being configured to transmit the image signal to the external device.

9. The camera emergency management circuit according to any one of claims 1 to 5, further comprising:

10. A black box comprising the camera emergency management circuit according to any one of claims 1 to 9.