Power supply control device for switching power supply and electronic device

Abstract

This application discloses a power supply control device and electronic device for a switching power supply. The switching power supply includes a safety capacitor, and the power supply control device includes a first switch group, a second switch group, and a controller. A first terminal of the first switch group is connected to the output terminal of the switching power supply, and a second terminal of the first switch group is connected to the power supply terminal of the load. A first terminal of the second switch group is connected to the ground terminal of the switching power supply, and a second terminal of the second switch group is connected to the ground terminal of the load. The controller is used to control the first and second switch groups to disconnect based on a stop command indicating that the load should stop. Thus, the power supply control device of this embodiment disconnects the external connection between the power supply terminal and the ground terminal of the load when the load stops, preventing leakage current from the switching power supply from flowing into the load. Users will not experience electric shock when touching the load when it stops, improving the user experience.

Description

Technical Field

[0001] This application relates to electrical safety protection technology, and more particularly to a power supply control device and electronic equipment for a switching power supply. Background Technology

[0002] Home appliances and other electronic devices are usually equipped with switching power supplies to convert external input power into power supply for the load. When the load is running, the switching power supply is connected to the power supply terminal of the load, and when the load stops, the connection between the switching power supply and the power supply terminal of the load is disconnected.

[0003] As users' demands for home appliances increase, some appliances are adding health functions. For example, air conditioners are equipped with water electrolysis modules to achieve functions such as sterilization, disinfection, and oxygen generation. When operating these appliances, users may come into contact with live parts of these health function loads. For instance, users need to add water to the water tank of the water electrolysis module in air conditioners regularly. However, although switching power supplies can achieve electrical isolation between input and output power supplies, in order to meet the electromagnetic compatibility requirements of electronic devices, safety capacitors are usually connected between the primary and secondary windings of the transformer in the switching power supply. The parasitic capacitance of the primary and secondary windings of the transformer, along with the safety capacitors, can cause a slight leakage current between the primary and secondary windings of the transformer. When the load is turned off, although the electronic device disconnects the power supply from the switching power supply to the load's power terminal, the ground terminal of the load remains connected to the ground terminal of the switching power supply, providing a leakage current path for the switching power supply. This results in users still experiencing a slight electric shock when touching the health function load even when it is turned off. Utility Model Content

[0004] In view of this, embodiments of this application provide a power supply control device and electronic device for a switching power supply, which aims to eliminate the possibility of electric shock when a user operates and sets the electronic device for the switching power supply.

[0005] The technical solution of this application embodiment is implemented as follows:

[0006] In a first aspect, embodiments of this application provide a power supply control device for a switching power supply, the switching power supply including a safety capacitor; the power supply control device includes:

[0007] A first switch group, wherein the first end of the first switch group is connected to the output end of the switching power supply, and the second end of the first switch group is connected to the power supply end of the load;

[0008] The second switch group has a first end connected to the grounding terminal of the switching power supply and a second end connected to the grounding terminal of the load.

[0009] The controller is used to control the first switch group and the second switch group to disconnect based on a shutdown command instructing the load to stop.

[0010] In some embodiments, the power supply control device further includes:

[0011] The third switch group has a first end connected to the controller and a second end connected to the feedback terminal of the load.

[0012] The controller is also used to control the third switch group to disconnect based on the shutdown command.

[0013] In some implementations, the first switch group includes:

[0014] A first switching transistor is disposed between the output terminal of the switching power supply and the power supply terminal of the load, and is used to control the connection relationship between the output terminal of the switching power supply and the power supply terminal of the load based on the on / off state of the first switching transistor.

[0015] The second switch is connected to the first switch and the controller respectively, and is used to control the first switch to turn off based on the second switch switching to the first on / off state;

[0016] The controller is also used to control the second switch to switch to the first on / off state based on the shutdown command.

[0017] In some implementations, the first switch includes:

[0018] The first transistor has its emitter connected to the output terminal of the switching power supply and its collector connected to the power supply terminal of the load.

[0019] The second switching transistor includes:

[0020] The second transistor has its base connected to the controller, its emitter connected to the ground terminal of the switching power supply, and its collector connected to the base of the first transistor.

[0021] The first transistor is a PNP transistor, and the second transistor is an NPN transistor.

[0022] In some implementations, the second switch group includes:

[0023] The third switching transistor is disposed between the ground terminal of the switching power supply and the ground terminal of the load, and is used to control the connection relationship between the ground terminal of the switching power supply and the ground terminal of the load based on the on / off state of the third switching transistor.

[0024] The controller is connected to the third switch tube, and the controller is also used to control the third switch tube to turn off based on the stop command.

[0025] In some implementations, the third switch includes:

[0026] The third transistor has its base connected to the controller, its collector connected to the ground terminal of the load, and its emitter connected to the ground terminal of the switching power supply.

[0027] The third transistor is an NPN transistor.

[0028] In some implementations, the third switch group includes:

[0029] Optical coupler, the optical coupler being connected to the second switch group;

[0030] The second switch group is used to control the optocoupler to be turned off when the second switch group is turned off.

[0031] In some embodiments, the power supply control device further includes:

[0032] The coil of the relay is used to control the on / off state of the relay's switching contacts based on the energized state of the coil.

[0033] The first switch group and the second switch group include the switch contacts; the controller is also used to switch the energization state of the coil based on the stop command, so that the first switch group and the second switch group are disconnected.

[0034] In some implementations, the third switch group includes the switch contacts; the controller is also configured to switch the energization state of the coil based on the shutdown command, thereby disconnecting the third switch group.

[0035] Secondly, embodiments of this application provide an electronic device, including a power supply control device, a switching power supply, and a load as described in the first aspect;

[0036] The switching power supply includes a safety capacitor; the power supply control device is connected to both the switching power supply and the load, and the switching power supply supplies power to the load via the power supply control device.

[0037] In some implementations, the load is surface-charged during operation.

[0038] The technical solution provided in this application embodiment includes a switching power supply with a safety capacitor. The power supply control device for the switching power supply includes a first switch group, a second switch group, and a controller. A first terminal of the first switch group is connected to the output terminal of the switching power supply, and a second terminal of the first switch group is connected to the power supply terminal of the load. A first terminal of the second switch group is connected to the ground terminal of the switching power supply, and a second terminal of the second switch group is connected to the ground terminal of the load. The controller is used to control the first and second switch groups to disconnect based on a stop command indicating that the load should stop. Thus, the power supply control device of this application embodiment disconnects the external connection between the load's power supply terminal and ground terminal when the load stops, preventing leakage current from the switching power supply from flowing into the load. Users will not experience electric shock when touching the load when it stops, improving the user experience. Attached Figure Description

[0039] Figure 1 This is a first structural schematic diagram of the power supply control device according to an embodiment of this application;

[0040] Figure 2 This is a schematic diagram of the switching power supply structure according to an embodiment of this application;

[0041] Figure 3 This is a schematic diagram of the structure of an electronic device in related technologies;

[0042] Figure 4 This is a second structural schematic diagram of the power supply control device according to an embodiment of this application;

[0043] Figure 5 This is a schematic diagram of the third structure of the power supply control device according to an embodiment of this application;

[0044] Figure 6 This is a schematic diagram of the fourth structure of the power supply control device according to an embodiment of this application;

[0045] Figure 7 This is a fifth structural schematic diagram of the power supply control device according to an embodiment of this application.

[0046] Explanation of reference numerals in the attached figures:

[0047] 1. Power supply control device; 11. First switch group; 12. Second switch group; 13. Third switch group;

[0048] 14. Controller; 141. First port; 142. Second port; 143. Third port;

[0049] 2. Switching power supply; 21. Transformer; 22. Fourth switching transistor; 3. Load; 31. Power supply terminal;

[0050] 32. Feedback terminal; 33. Grounding terminal. Detailed Implementation

[0051] The present application will now be described in further detail with reference to the accompanying drawings and embodiments.

[0052] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0053] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the term "connection" should be understood as electrical connection; an electrical connection can be a direct connection, an indirect connection through an intermediate medium (such as a resistor), or a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0054] This application provides a power supply control device for a switching power supply, such as... Figure 1 As shown, the power supply control device 1 includes a first switch group 11, a second switch group 12, and a controller 14. The first end of the first switch group 11 is connected to the output terminal of the switching power supply 2, and the second end of the first switch group 11 is connected to the power supply terminal of the load 3. The first end of the second switch group 12 is connected to the ground terminal of the switching power supply 2, and the second end of the second switch group 12 is connected to the ground terminal of the load 3. The controller 14 is used to control the first switch group 11 and the second switch group 12 to disconnect based on a stop command indicating that the load 3 should stop.

[0055] Here, the power supply control device 1, the switching power supply 2, and the load 3 are installed in the electronic equipment. The power supply control device 1 is connected to the switching power supply 2 and the load 3 respectively. The switching power supply 2 supplies power to the load 3 through the power supply control device 1.

[0056] Here, the controller 14 is connected to the first switch group 11 and the second switch group 12 respectively, and is used to control the on / off state of the first switch group 11 and the second switch group 12.

[0057] Here, the form of controller 14 is not specifically limited in this embodiment. Controller 14 can be a digital signal processor (DSP), a programmable logic device (PLD), a complex programmable logic device (CPLD), a field programmable gate array (FPGA), a general-purpose processor, a controller, a micro controller unit (MCU), a microprocessor, or an electronic component. In some embodiments, controller 14 is preferably a microcontroller (MCU).

[0058] Here, the type of switching power supply 2 includes, but is not limited to, flyback switching power supply, forward switching power supply and push-pull switching power supply. This application embodiment does not specifically limit this.

[0059] Here, the switching power supply 2 includes safety capacitors.

[0060] Specifically, the safety capacitors are connected to the primary and secondary windings of the transformer in the switching power supply 2, respectively. By bridging the primary and secondary windings of the transformer with the safety capacitors, the common-mode interference current during the operation of the switching power supply 2 can be suppressed to meet the relevant electromagnetic compatibility standards.

[0061] In some embodiments, the structure of the switching power supply 2 is as follows: Figure 2 As shown. The switching power supply 2 is a flyback switching power supply, including a transformer 21 and a fourth switching transistor 22. The primary side of the transformer 21 is connected to an external input power supply, and the secondary side of the transformer 21 is the output terminal of the switching power supply 2. The fourth switching transistor 22 is connected to the primary side of the transformer 21. Safety capacitors CY1 and CY2 are installed between the primary and secondary sides of the transformer 21. When the switching power supply 2 is running, by switching the on / off state of the fourth switching transistor 22, an electrical signal is output to the secondary side of the transformer 21.

[0062] It should be noted that in related technologies, such as Figure 3As shown, electronic devices typically have a switch group between the output of the switching power supply and the power supply terminal of the load. When the load stops, this switch group is opened, preventing the switching power supply from continuing to supply power to the load. However, since the grounding terminal of the switching power supply and the grounding terminal of the load remain connected, if a safety capacitor is connected between the primary and secondary windings of the switching power supply transformer, the parasitic capacitance of the primary and secondary windings of the transformer and the connected safety capacitor will cause a weak leakage current between the primary and secondary windings of the transformer. Since the grounding terminal of the switching power supply and the grounding terminal of the load can form a leakage current path, the leakage current will flow into the load through the grounding terminal of the load. Therefore, when a user touches the live part of the load, even if the load is stopped, the user will still experience a slight, tingling electric shock due to the leakage current of the switching power supply, affecting the user experience.

[0063] It should be noted that, for the switching power supply 2 with safety capacitors, the power supply control device 1 of this application embodiment includes a first switch group 11 connected to the power supply terminal of the load 3 and a second switch group 12 connected to the ground terminal of the load 3. The switching power supply 2 supplies power to the load 3 through the power supply control device 1 of this application embodiment. The instruction to stop the load is not only used to control the working state of the load, but also to switch the on / off state of the power supply control device. When the load 3 stops, the controller 14 controls the first switch group 11 and the second switch group 12 to disconnect, so that the power supply terminal and the ground terminal of the load 3 are disconnected from the switching power supply 2.

[0064] It is understood that the power supply control device 1 in this application embodiment cuts off the external connection between the power supply terminal and the ground terminal of the load 3 when the load 3 stops, so that the leakage current of the switching power supply 2 cannot flow into the load 3. When the load 3 stops, the user will not feel an electric shock when touching the load 3, thus improving the user experience.

[0065] In some embodiments, such as Figure 4 As shown, the power supply control device 1 also includes a third switch group 13. The first end of the third switch group 13 is connected to the controller 14, and the second end of the third switch group 13 is connected to the feedback terminal (Feedback, FB) of the load 3.

[0066] The controller 14 is also used to control the third switch group 13 to disconnect based on the stop command.

[0067] It is understood that the controller 14 and the load 3 may be connected by a signal line for transmitting feedback signals. In order to prevent leakage current from entering the load 3 through the feedback terminal of the load 3, in this embodiment, the power supply control device 1 sets a third switch group 13 between the controller 14 and the feedback terminal of the load 3. When the load 3 stops, the controller 14 controls the first switch group 11, the second switch group 12 and the third switch group 13 to disconnect, so that the power supply terminal, ground terminal and feedback terminal of the load 3 are all disconnected from the outside.

[0068] It should be noted that the switching group of the power supply control device 1 in this application embodiment can be composed of one or more switching transistors, including but not limited to transistors, MOSFETs and IGBTs. The switching group can also include switching devices such as electromagnetic relays or solid-state relays. The switching group can be a multi-channel integrated device or multiple single-channel switching devices. This application embodiment does not specifically limit the type and composition structure of the switching group of the power supply control device 1. Any switching group controlled by the controller 14 and capable of switching between the on and off states is applicable to the power supply control device 1 in this application embodiment.

[0069] The power supply control device 1 of this application will be described below with reference to specific embodiments.

[0070] In some embodiments, the first switch group 11 includes a first switch transistor and a second switch transistor; the second switch group 12 includes a third switch transistor; and the third switch group 13 includes an optocoupler.

[0071] The first switching transistor is located between the output terminal of the switching power supply 2 and the power supply terminal of the load 3, and is used to control the connection between the output terminal of the switching power supply 2 and the power supply terminal of the load 3 based on the on / off state of the first switching transistor; the second switching transistor is connected to the first switching transistor and the controller 14 respectively, and is used to control the first switching transistor to be cut off based on the second switching transistor switching to the first on / off state.

[0072] The third switch is located between the grounding terminal of the switching power supply 2 and the grounding terminal of the load 3, and is used to control the connection relationship between the grounding terminal of the switching power supply 2 and the grounding terminal of the load 3 based on the on / off state of the third switch; the controller 14 is connected to the third switch.

[0073] The optocoupler is connected to the second switch group 12; the second switch group 12 is used to control the optocoupler to be turned off based on the opening of the second switch group 12.

[0074] The controller 14 is also used to control the second switch to switch to the first on / off state based on the shutdown command; the controller 14 is also used to control the third switch to turn off based on the shutdown command.

[0075] Here, when the first switch is turned on, the output terminal of the control power supply 2 is connected to the power supply terminal of the load 3; when the first switch is turned off, the output terminal of the control power supply 2 is disconnected from the power supply terminal of the load 3; when the third switch is turned on, the ground terminal of the control power supply 2 is connected to the ground terminal of the load 3; when the third switch is turned off, the ground terminal of the control power supply 2 is disconnected from the ground terminal of the load 3.

[0076] Here, the second switch group 12 is used to control the optocoupler to be cut off based on the second switch group 12 being disconnected. Specifically, when the third switch of the second switch group 12 is cut off, the optocoupler is controlled to be cut off.

[0077] Here, the first on / off state can be either on or off; the second switch is connected to the control terminal of the first switch. When the second switch switches to the first on / off state, the control signal of the first switch switches is switched, causing the first switch to turn off, and the output terminal of the switching power supply 2 is disconnected from the power supply terminal of the load 3.

[0078] It is understood that in this embodiment, the controller 14 controls the second switch to switch to the first on / off state and controls the third switch to turn off based on the shutdown command, so that the first switch group 11, the second switch group 12 and the third switch group 13 are all disconnected, and the power supply terminal, ground terminal and feedback terminal of the load 3 are all disconnected from the outside.

[0079] In one example of this embodiment, the first switching transistor includes a first transistor, the second switching transistor includes a second transistor, and the third switching transistor includes a third transistor; wherein the first transistor is a PNP transistor, the second transistor is an NPN transistor, and the third transistor is an NPN transistor. Specifically, the emitter of the first transistor is connected to the output terminal of the switching power supply 2, and the collector of the first transistor is connected to the power supply terminal of the load 3; the base of the second transistor is connected to the controller 14, the emitter of the second transistor is connected to the ground terminal of the switching power supply 2, and the collector of the second transistor is connected to the base of the first transistor; the base of the third transistor is connected to the controller 14, the collector of the third transistor is connected to the ground terminal of the load 3, and the emitter of the third transistor is connected to the ground terminal of the switching power supply 2.

[0080] Here, the structure of the power supply control device 1 in this example is as follows: Figure 5 As shown. The power supply terminal of load 3 is connected to the collector of the first transistor Q1. The electrical signal VDD output by the switching power supply 2 supplies power to load 3 through the first transistor Q1. The base of the first transistor Q1 is connected to the collector of the second transistor Q2 through the first resistor R1. The emitter of the second transistor Q2 is connected to the ground terminal of the switching power supply 2. The first port 141 of the controller 14 is connected to the base of the second transistor Q2 through the second resistor R2. The first on / off state of the second transistor Q2 is the off state. The controller 14 controls the first port 141 to output a low-level signal based on the stop command, so that the second transistor Q2 is turned off. Because the second transistor Q2 is in the off state, the first transistor Q1 is turned off. The electrical signal VDD cannot be supplied to the power supply terminal 31 of load 3, and the leakage current path between the power supply terminal 31 of load 3 and the output terminal of the switching power supply 2 is cut off.

[0081] Here, the third port 143 of the controller 14 is connected to the base of the third transistor Q3 via the seventh resistor R7. Based on the shutdown command, the controller 14 controls the third port 143 to output a low-level signal, so that the third transistor Q3 is turned off, and the leakage path between the ground terminal 33 of the load 3 and the ground terminal of the switching power supply 2 is cut off.

[0082] Here, the first input terminal of the optocoupler IC is connected to the feedback terminal 32 of the load 3 via the fifth resistor R5, the second input terminal of the optocoupler IC is connected to the collector of the third transistor Q3, and a sixth resistor R6 is provided between the first and second input terminals of the optocoupler IC; the electrical signal VCC output by the switching power supply 2 is input to the second port 142 of the controller 14 via the fourth resistor R4 and the third resistor R3, the first output terminal of the optocoupler IC is connected to the connection point between the third resistor R3 and the fourth resistor R4, the second output terminal of the optocoupler IC is connected to the ground terminal of the switching power supply 2, and a first capacitor C1 is provided between the second port 142 of the controller 14 and the ground terminal of the switching power supply 2. In an easy-to-understand way, when the third transistor Q3 is turned on, the input terminal of the optocoupler IC is connected to the ground terminal of the switching power supply 2. The feedback signal output by the load 3 is isolated and output to the controller 14 through the optocoupler IC. There is no leakage current path between the controller 14 and the load 3. The controller 14 controls the third port 143 to output a low-level signal based on the stop command, so that the third transistor Q3 is turned off, the input terminal of the optocoupler IC and the ground terminal of the switching power supply 2 are disconnected, and the controller 14 and the feedback terminal 32 of the load 3 are disconnected.

[0083] In the above example, the controller 14 controls both the first port 141 and the third port 143 to output low-level signals based on the stop command; based on this, in another example of this embodiment, such as Figure 6 As shown, the first port 141 of the controller 14 is connected to the base of the second transistor Q2 and the base of the third transistor Q3 respectively. The on / off state of the second transistor Q2 and the third transistor Q3 is controlled based on the same port of the controller 14. The controller 14 controls the first port 141 to output a low-level signal based on the stop command, so that the first switch group 11, the second switch group 12 and the third switch group 13 of the power supply control device 1 are all disconnected.

[0084] In some embodiments, the power supply control device 1 further includes a relay coil. The coil is used to control the on / off state of the relay's switching contacts based on the coil's energization state.

[0085] The first switch group 11, the second switch group 12 and the third switch group 13 include the switch contacts of the relay; the controller 14 is also used to switch the energization state of the coil based on the stop command, so that the first switch group 11, the second switch group 12 and the third switch group 13 are disconnected.

[0086] Understandably, the coil, the first switch group 11, the second switch group 12, and the third switch group 13 constitute a relay with multiple switch contacts. If the relay is a normally open relay, the controller 14 controls the coil to stop being energized based on the stop command, causing the switch contacts in the first switch group 11, the second switch group 12, and the third switch group 13 to open. If the relay is a normally closed relay, the controller 14 controls the coil to be energized based on the stop command, causing the switch contacts in the first switch group 11, the second switch group 12, and the third switch group 13 to open.

[0087] Here, the structure of the power supply control device 1 in this example is as follows: Figure 7 As shown. The power supply control device 1 includes a relay RY, which includes a coil RL, a first switch contact K1, a second switch contact K2, and a third switch contact K3. The first switch contact K1, as a first switch group 11, is connected to the output terminal of the switching power supply 2 and the power supply terminal 31 of the load 3, respectively. The electrical signal VDD output by the switching power supply 2 supplies power to the load 3 via the first switch contact K1. The second switch contact K2, as a second switch group 12, is connected to the ground terminal of the switching power supply 2 and the ground terminal 33 of the load 3, respectively. The third switch contact K3, as a third switch group 13, is connected to the second port 142 of the controller 14 and the feedback terminal 32 of the load 3, respectively.

[0088] Here, the power supply control device 1 also includes a fourth transistor Q4, which is an NPN transistor. The base of the fourth transistor Q4 is connected to the first port 141 of the controller 14, the collector of the fourth transistor Q4 is connected to the first end of the coil RL, and the emitter of the fourth transistor Q4 is connected to the ground terminal of the switching power supply 2. The second end of the coil RL is connected to the output terminal of the switching power supply 2.

[0089] It is understandable that the relay RY is a normally open relay. The controller 14 controls the second port 142 to output a low-level signal based on the stop command, so that the fourth transistor Q4 is turned off. After the fourth transistor Q4 is turned off, the electrical signal VDD stops flowing into the coil RL. Based on the de-energization of the coil RL, the controller controls the first switch contact K1, the second switch contact K2 and the third switch contact K3 to open, so that the power supply terminal 31, the ground terminal 33 and the feedback terminal 32 of the load 3 are all disconnected from the outside.

[0090] In another example, corresponding coils can be set for the switch contacts in the first switch group 11, the second switch group 12 and the third switch group 13 respectively. That is, the power supply control device 1 includes three single-circuit switch relays to control the connection relationship between the load 3 and the outside. The controller 14 controls the energization state of the coils of each relay based on the shutdown command.

[0091] Based on the aforementioned power supply control device, this application embodiment also provides an electronic device, which includes a power supply control device 1, a switching power supply 2, and a load 3. The switching power supply 2 includes a safety capacitor; the power supply control device 1 is connected to both the switching power supply 2 and the load 3, and the switching power supply 2 supplies power to the load 3 via the power supply control device 1.

[0092] In some embodiments, the surface of load 3 is charged when the load is running.

[0093] Here, the live part of the load 3 is easily touched by the user. When the load stops, even if the power supply terminal of the load 3 is disconnected from the output terminal of the switching power supply 2, the leakage current of the switching power supply 2 will still flow into the load 3 through the connected ground terminal. In this embodiment of the electronic device, when the load stops, the power supply control device 1 controls the load 3 to disconnect from the output terminal and ground terminal of the switching power supply 2, cuts off the leakage current path of the switching power supply 2, and avoids the user from feeling an electric shock when touching the load 3.

[0094] In some embodiments, the electronic device is an air conditioner with health functions, including a water electrolysis module. The power supply control device 1 of the air conditioner is located between the switching power supply 2 and the water electrolysis module. When the water electrolysis module is running, the electrical signal output by the switching power supply 2 is fed into the electrodes of the water electrolysis module. The electrodes discharge to electrolyze the water in the water tank of the water electrolysis module to achieve sterilization, disinfection, and oxygen production. When the water electrolysis module is stopped, the power supply control device 1 controls the water electrolysis module to disconnect from the external electrical connection to prevent users from experiencing electric shock when touching the water tank while adding or changing water.

[0095] It should be noted that terms such as "first" and "second" are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0096] Furthermore, the technical solutions described in the embodiments of this application can be combined arbitrarily without conflict.

[0097] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A power supply control device for a switching power supply, characterized in that, The switching power supply includes safety capacitors; the power supply control device includes: A first switch group, wherein the first end of the first switch group is connected to the output end of the switching power supply, and the second end of the first switch group is connected to the power supply end of the load; The second switch group has a first end connected to the grounding terminal of the switching power supply and a second end connected to the grounding terminal of the load. The controller is used to control the first switch group and the second switch group to disconnect based on a shutdown command instructing the load to stop.

2. The power supply control device according to claim 1, characterized in that, The power supply control device also includes: The third switch group has a first end connected to the controller and a second end connected to the feedback terminal of the load. The controller is also used to control the third switch group to disconnect based on the shutdown command.

3. The power supply control device according to claim 2, characterized in that, The first switch group includes: A first switching transistor is disposed between the output terminal of the switching power supply and the power supply terminal of the load, and is used to control the connection relationship between the output terminal of the switching power supply and the power supply terminal of the load based on the on / off state of the first switching transistor. The second switch is connected to the first switch and the controller respectively, and is used to control the first switch to turn off based on the second switch switching to the first on / off state; The controller is also used to control the second switch to switch to the first on / off state based on the shutdown command.

4. The power supply control device according to claim 3, characterized in that, The first switching transistor includes: The first transistor has its emitter connected to the output terminal of the switching power supply and its collector connected to the power supply terminal of the load. The second switching transistor includes: The second transistor has its base connected to the controller, its emitter connected to the ground terminal of the switching power supply, and its collector connected to the base of the first transistor. The first transistor is a PNP transistor, and the second transistor is an NPN transistor.

5. The power supply control device according to claim 3, characterized in that, The second switch group includes: The third switching transistor is disposed between the ground terminal of the switching power supply and the ground terminal of the load, and is used to control the connection relationship between the ground terminal of the switching power supply and the ground terminal of the load based on the on / off state of the third switching transistor. The controller is connected to the third switch tube, and the controller is also used to control the third switch tube to turn off based on the stop command.

6. The power supply control device according to claim 5, characterized in that, The third switching transistor includes: The third transistor has its base connected to the controller, its collector connected to the ground terminal of the load, and its emitter connected to the ground terminal of the switching power supply. The third transistor is an NPN transistor.

7. The power supply control device according to claim 5, characterized in that, The third switch group includes: Optical coupler, the optical coupler being connected to the second switch group; The second switch group is used to control the optocoupler to be turned off when the second switch group is turned off.

8. The power supply control device according to claim 2, characterized in that, The power supply control device also includes: The coil of the relay is used to control the on / off state of the relay's switching contacts based on the energized state of the coil. The first switch group and the second switch group include the switch contacts; the controller is also used to switch the energization state of the coil based on the stop command, so that the first switch group and the second switch group are disconnected.

9. The power supply control device according to claim 8, characterized in that, The third switch group includes the switch contacts; the controller is also used to switch the energization state of the coil based on the stop command, so that the third switch group is disconnected.

10. An electronic device, characterized in that, Includes the power supply control device, switching power supply, and load as described in any one of claims 1 to 9; The switching power supply includes a safety capacitor; the power supply control device is connected to both the switching power supply and the load, and the switching power supply supplies power to the load via the power supply control device.

11. The electronic device according to claim 10, characterized in that, The load becomes charged on its surface during operation.

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