Overcurrent protection circuit applied to intelligent socket and intelligent socket

Abstract

The embodiment of the utility model discloses an over-current protection circuit applied to an intelligent socket and the intelligent socket, the circuit comprises an over-current latch module and a control module, and the control module is respectively connected with the over-current latch module and an input power supply; the overcurrent latch module is used for outputting a low-level control signal when the output current of the intelligent socket is smaller than a preset current; the control module is also used for outputting and latching a high-level control signal when the output current is greater than the preset current; the control module is used for conducting a power supply loop of an input power supply and the intelligent socket when receiving a low-level control signal; and the controller is also used for disconnecting the power supply loop when receiving the high-level control signal. According to the embodiment of the utility model, the overcurrent latch module used for detecting the output current is arranged, and the control signal is output when the intelligent socket is in an overcurrent state, so that the control module disconnects the power supply loop of the intelligent socket, the overcurrent detection and protection of the intelligent socket can be effectively realized, the reliability of the intelligent socket is improved, and the cost is reduced.

Description

TECHNICAL FIELD

[0001] The utility model embodiment relates to field, especially intelligent socket protection circuit is applied to intelligent socket's overcurrent protection circuit and intelligent socket of intelligent socket protection circuit application. BACKGROUND

[0002] With the development of economy, intelligent home has also obtained greater development, wherein, intelligent socket is a brand new concept safety socket, it is the new type intelligent safety socket that is integrated one way programmable automatic control safety energy saving converter and electric appliance intelligent standby power saving socket, the main function of this type intelligent socket is power saving and safety.

[0003] The existing intelligent socket has the defects of easy overtemperature and overcurrent under long time load, which can easily lead to damage of the socket, and generally uses CPU control switch, and the control circuit is complex and the maintenance cost is high. INVENTION CONTENTS

[0004] The utility model embodiment mainly solves the technical problem that provides a kind of overcurrent protection circuit and intelligent socket applied to intelligent socket, and can solve the defects of easy overcurrent under long time load of existing intelligent socket.

[0005] To solve the above technical problems, one technical scheme of the utility model is: provide a kind of overcurrent protection circuit applied to intelligent socket, including: overcurrent latching module and control module, the control module is connected with the overcurrent latching module and input power respectively;The overcurrent latching module is used to output low-level control signal when the output current of the intelligent socket is less than preset current;It is also used to output and latch high-level control signal when the output current is greater than preset current;The control module is used to turn on the power supply loop of the input power and the intelligent socket when receiving the low-level control signal;It is also used to disconnect the power supply loop when receiving the high-level control signal.

[0006] In some embodiments, the overcurrent latching module constitutes a positive feedback loop with the control signal as a feedback signal, and when the control signal is high, the high-level control signal is latched.

[0007] In some embodiments, the overcurrent latch module includes a sampling unit, an amplifying unit and a feedback unit, the amplifying unit is connected to the sampling unit and the feedback unit respectively, the feedback unit is connected to the control module, and the sampling unit is connected to the output neutral terminal of the smart socket; the sampling unit is used to output a sampling voltage under the action of the output current; the amplifying unit is used to amplify the sampling voltage and output a driving voltage; the feedback unit forms a positive feedback loop with the control signal as the feedback signal, and the feedback unit is used to output a low-level control signal when the driving voltage is less than a preset reference voltage; and is also used to output and latch the high-level control signal when the driving voltage is greater than the preset reference voltage; when the output current is less than the preset current, the driving voltage is less than the preset reference voltage; when the output current is greater than the preset current, the driving voltage is greater than the preset reference voltage.

[0008] In some embodiments, the feedback unit is further configured to output the high-level control signal when the level of the control signal is greater than the preset reference voltage.

[0009] In some embodiments, the control module includes a switch drive unit and a relay unit, the relay unit is connected to the input power supply and the switch drive unit, respectively, and the switch drive unit is connected to the overcurrent latch module; the switch drive unit is used to output a low-level switch signal under the action of the high-level control signal, and to output a high-level switch signal under the action of the low-level control signal; the relay unit is used to turn on the power supply circuit when the conduction signal is high, and to disconnect the power supply circuit when the conduction signal is low.

[0010] In some embodiments, the sampling unit includes a resistor R5, the amplifying unit includes a resistor R3, a resistor R4, a resistor R6, a resistor R9, a capacitor C2, a capacitor C3, a capacitor C6 and an operational amplifier U1A, the first end of the resistor R5 and the first end of the resistor R4 are grounded, the second end of the resistor R5 is connected to the output neutral terminal of the smart socket and the first end of the resistor R6, the first end of the capacitor C2 is connected to the first end of the resistor R3 and the third power supply, the second end of the resistor R3 is connected to the in-phase input terminal of the operational amplifier U1A, the capacitor C3 is connected to the first end of the resistor R6 and the third power supply, the second end of the resistor R3 is connected to the in-phase input terminal of the operational amplifier U1A, the capacitor C3 is connected to the first end of the resistor R4 and the first end of the resistor R5. The second end of the resistor R4 is connected to the second end of the capacitor C2; the second end of the resistor R6 is connected to the inverting input terminal of the operational amplifier U1A, the first end of the resistor R9 and the first end of the capacitor C6, the first power input terminal of the operational amplifier U1A is connected to the second power supply and the first end of the capacitor C3, the second end of the resistor R9 is connected to the second end of the capacitor C6, the output terminal of the operational amplifier U1A and the input terminal of the feedback unit, and the second end of the capacitor C3 and the second power input terminal of the operational amplifier U1A are grounded.

[0011] In some embodiments, the feedback unit includes a comparator U2A, a resistor R1, a resistor R2, a resistor R7, a resistor R8, a capacitor C1, a capacitor C4, a capacitor C5, a diode D1, and a diode D4. The first power input terminal of the comparator U2A is connected to the second power supply, the first end of the capacitor C1, the first end of the resistor R2, and the first end of the resistor R1. The inverting input terminal of the comparator U2A is connected to the second end of the resistor R1, the first end of the resistor R8, and the first end of the capacitor C5. The non-inverting input terminal of the comparator U2A is connected to the second end of the resistor R1, the first end of the resistor R8, and the first end of the capacitor C5. The first end of the resistor R7, the first end of the capacitor C4, the cathode of the diode D1 and the output end of the amplifying unit are connected; the output end of the comparator U2A is connected to the second end of the resistor R2, the anode of the diode D4 and the anode of the diode D1, the cathode of the diode D4 is connected to the input end of the control module, and the second end of the capacitor C1, the second power input end of the comparator U2A, the second end of the resistor R8, the second end of the capacitor C5, the second end of the resistor R7 and the second end of the capacitor C4 are grounded.

[0012] In some embodiments, the switch driving unit includes a transistor Q1, a resistor R14, a resistor R15, a resistor R16, a resistor R17 and a capacitor C10, the base of the transistor Q1 is connected to the first end of the resistor R17, the first end of the capacitor C10 and the first end of the resistor R15, the second end of the resistor R15 is connected to the output end of the overcurrent latch module, the first end of the resistor R14 is connected to the third power supply, the second end of the resistor R14 is connected to the first end of the resistor R16, the collector of the transistor Q1 and the signal input end of the relay unit, the emitter of the transistor Q1, the second end of the resistor R17, the second end of the capacitor C10 and the second end of the resistor R16 are grounded.

[0013] In some embodiments, the relay unit includes a MOS transistor Q2, a diode D3, and a relay RLY1, the drain of the MOS transistor Q2 is connected to the anode of the diode D3 and the first coil end of the relay RLY1, the gate of the MOS transistor Q2 is connected to the output end of the switch drive unit, and the source of the MOS transistor Q2 is grounded; the cathode of the diode D3 is connected to the second coil end of the relay RLY1, the first connection end of the relay RLY1 is connected to the input power supply, and the second connection end of the relay RLY1 is connected to the output live wire end of the smart socket.

[0014] In order to solve the above technical problems, another technical solution adopted by the present invention is to provide a smart socket, including: the overcurrent protection circuit applied to the smart socket as described above.

[0015] The beneficial effects of the embodiments of the present invention are as follows: Different from the prior art, the embodiments of the present invention provide an overcurrent latch module for detecting the output current, and output a control signal when the smart socket overcurrent occurs, so that the control module disconnects the power supply circuit of the smart socket, thereby effectively realizing overcurrent detection and protection of the smart socket, improving the reliability of the smart socket, and reducing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a structural diagram of an overcurrent protection circuit applied to a smart socket provided by an embodiment of the present utility model;

[0017] Figure 2 This is a structural diagram of an overcurrent latch module provided by an embodiment of the present utility model;

[0018] Figure 3 This is a structural diagram of a control module provided by an embodiment of the present utility model;

[0019] Figure 4The utility model embodiment provides a kind of circuit schematic diagram of overcurrent latching module;

[0020] Figure 5 The utility model embodiment provides a kind of circuit schematic diagram of control module;

[0021] Figure 6 The utility model embodiment provides another kind of structure schematic view of overcurrent protection circuit applied to intelligent socket;

[0022] Figure 7 The utility model embodiment provides a kind of structure schematic view of overtemperature latching module;

[0023] Figure 8 The utility model embodiment provides a kind of circuit schematic diagram of overtemperature latching module. DETAILED DESCRIPTION

[0024] In order to facilitate understanding of the utility model, the utility model is described in more detail below in conjunction with the drawings and specific embodiments. It should be noted that when an element is described as "fixed to" another element, it can be directly on another element, or one or more intervening elements can be present therebetween. When an element is described as "connected" to another element, it can be directly connected to another element, or one or more intervening elements can be present therebetween. The terms "vertical", "horizontal", "left", "right" and similar expressions used in the specification are for illustrative purposes only.

[0025] Unless otherwise defined, all technical and scientific terms used in the specification are the same as those commonly understood by those skilled in the art to which the utility model belongs. The terms used in the specification of the utility model are only for the purpose of describing the specific embodiments, not for limiting the utility model. The term "and / or" used in the specification includes any and all combinations of one or more related listed items.

[0026] To solve the existing smart socket long time with load easy overcurrent and other shortcomings, the present application embodiment provides a kind of overcurrent protection circuit applied to intelligent socket, its structure schematic view as shown in Figure 1 The overcurrent protection circuit applied to intelligent socket includes overcurrent latching module 100 and control module 200. Control module 200 is connected with overcurrent latching module 100, input power supply 20 and intelligent socket 30 respectively.

[0027] The overcurrent latch module 100 is configured to output a low-level control signal when the output current of the smart socket 30 is less than a preset current. It is also configured to output and latch a high-level control signal when the output current of the smart socket 30 is greater than the preset current. By way of example and not limitation, the preset current may be 17A. When the output current of the smart socket 30 is less than 17A, the overcurrent latch module 100 outputs a low-level control signal; when the output current of the smart socket 30 is greater than 17A, the overcurrent latch module 100 outputs and latches a high-level control signal.

[0028] It should be noted that the latching is implemented in the following manner: the overcurrent latch module 100 forms a positive feedback loop with the control signal as a feedback signal, so as to latch the high-level control signal when the control signal is at a high level.

[0029] The control module 200 is configured to connect the power supply circuit between the input power source 20 and the smart socket 30 upon receiving a low-level control signal, and to disconnect the power supply circuit upon receiving a high-level control signal. Specifically, when the output current of the smart socket 30 is less than a preset current, the control module 200 connects the power supply circuit between the input power source 20 and the smart socket 30; when the output current of the smart socket 30 is greater than the preset current, the control module 200 disconnects the power supply circuit between the input power source 20 and the smart socket 30.

[0030] In some embodiments of the present application, the structural diagram of the overcurrent latch module 100 is as follows: Figure 2 As shown, the overcurrent latch module 100 includes a sampling unit 110, an amplifying unit 120 and a feedback unit 130. The amplifying unit 120 is connected to the sampling unit 110 and the feedback unit 130 respectively. The feedback unit 130 is connected to the control module 200. The sampling unit 110 is connected to the output neutral terminal 31 of the smart socket 30.

[0031] The sampling unit 110 is configured to output a sampled voltage in response to the output current. The sampling unit 110 converts the sampled current into a sampled voltage. For example, the sampling unit can be implemented using a sampling resistor. The amplification unit 120 amplifies the sampled voltage and outputs a drive voltage. The feedback unit 130 forms a positive feedback loop using the control signal as the feedback signal. The feedback unit 130 outputs a low-level control signal when the drive voltage is less than a preset reference voltage, and outputs and latches a high-level control signal when the drive voltage is greater than the preset reference voltage. Furthermore, the feedback unit 130 outputs a high-level control signal when the control signal level is greater than the preset reference voltage, thereby implementing a signal latching function.

[0032] In the embodiment of the present application, when the output current is less than the preset current, the driving voltage is less than the preset reference voltage; when the output current is greater than the preset current, the driving voltage is greater than the preset reference voltage.

[0033] In some embodiments of the present application, the structural diagram of the control module 200 is as follows: Figure 3 As shown, the control module 200 includes a switch driving unit 210 and a relay unit 220. The relay unit 220 is connected to the input power supply 20, the smart socket 30 and the switch driving unit 210 respectively, and the switch driving unit 210 is connected to the overcurrent latch module 100.

[0034] The switch drive unit 210 is configured to output a low-level switch signal upon receiving a high-level control signal, and to output a high-level switch signal upon receiving a low-level control signal. The relay unit 220 is configured to connect the power supply circuit between the input power source 20 and the smart socket 30 upon receiving a high-level switch signal, and to disconnect the power supply circuit between the input power source 20 and the smart socket 30 upon receiving a high-level switch signal.

[0035] In some embodiments of the present application, the circuit schematic diagram of the overcurrent latch module 100 is as follows: Figure 4 As shown, the sampling unit 110 includes a resistor R5, the amplifying unit 120 includes a resistor R3, a resistor R4, a resistor R6, a resistor R9, a capacitor C2, a capacitor C3, a capacitor C6 and an operational amplifier U1A, and the feedback unit 130 includes a comparator U2A, a resistor R1, a resistor R2, a resistor R7, a resistor R8, a capacitor C1, a capacitor C4, a capacitor C5, a diode D1 and a diode D4.

[0036] A first end of resistor R5 and a first end of resistor R4 are grounded, a second end of resistor R5 is connected to the output neutral terminal OUT-N of the smart socket and a first end of resistor R6, a first end of capacitor C2 is connected to the first end of resistor R3 and a third power supply (taking 1.65V as an example), and a second end of resistor R3 is connected to the non-inverting input terminal of operational amplifier U1A, the second end of resistor R4, and the second end of capacitor C2.

[0037] The second end of resistor R6 is connected to the inverting input terminal of operational amplifier U1A, the first end of resistor R9 and the first end of capacitor C6, the first power input terminal of operational amplifier U1A is connected to the second power supply (taking 5V as an example) and the first end of capacitor C3, the second end of resistor R9 is connected to the second end of capacitor C6, the output terminal of operational amplifier U1A and the non-inverting input terminal of comparator U2A, and the second end of capacitor C3 and the second power input terminal of operational amplifier U1A are connected to GND.

[0038] The first power input terminal of the comparator U2A is connected to the second power supply (taking 5V as an example), the first end of the capacitor C1, the first end of the resistor R2 and the first end of the resistor R1, the inverting input terminal of the comparator U2A is connected to the second end of the resistor R1, the first end of the resistor R8 and the first end of the capacitor C5, and the non-inverting input terminal of the comparator U2A is connected to the first end of the resistor R7, the first end of the capacitor C4 and the cathode of the diode D1.

[0039] The output end of the comparator U2A is connected to the second end of the resistor R2, the anode of the diode D4, and the anode of the diode D1. The cathode of the diode D4 is connected to the input end of the control module. The second end of the capacitor C1, the second power input end of the comparator U2A, the second end of the resistor R8, the second end of the capacitor C5, the second end of the resistor R7, and the second end of the capacitor C4 are grounded.

[0040] In some embodiments of the present application, the circuit schematic diagram of the control module 200 is as follows: Figure 5 As shown, the switch driving unit 210 includes a transistor Q1 , a resistor R14 , a resistor R15 , a resistor R16 , a resistor R17 and a capacitor C10 , and the relay unit 220 includes a MOS transistor Q2 , a diode D3 and a relay RLY1 .

[0041] The drain of the MOS transistor Q2 is connected to the anode of the diode D3 and the first coil terminal of the relay RLY1, and the source of the MOS transistor Q2 is grounded. The base of the transistor Q1 is connected to the first end of the resistor R17, the first end of the capacitor C10, and the first end of the resistor R15. The second end of the resistor R15 is connected to the output terminal of the overcurrent latch module. The first end of the resistor R14 is connected to the first power supply (using +3.3V as an example). The second end of the resistor R14 is connected to the first end of the resistor R16, the collector of the transistor Q1, and the gate of the MOS transistor Q2. The emitter of the transistor Q1, the second end of the resistor R17, the second end of the capacitor C10, and the second end of the resistor R16 are grounded to GND.

[0042] The cathode of the diode D3 is connected to the second coil terminal of the relay RLY1 and the second power supply (taking +5V as an example), the first connection terminal of the relay RLY1 is connected to the input power IN-L, and the second connection terminal of the relay RLY1 is connected to the output live wire terminal OUT-L of the smart socket.

[0043] The specific working principle is as follows: after the smart socket is powered on, the relay RLY1 is automatically closed. After the load is inserted (that is, the port CN2 of the smart socket is connected to the load), when the output current of the smart socket to the load does not exceed the preset current, after the operational amplifier current is sampled, the output terminal voltage of the operational amplifier U1A is less than the preset voltage (in the embodiment of the present application, the preset current is 17A, and the output voltage of the third power supply is 1.65V, so the preset reference voltage of the operational amplifier U1A is 1.65+17*1.414*0.05=2.85V), and the voltage at the non-inverting input terminal of the comparator U2A is less than the voltage at the inverting input terminal. The output of comparator U2A flips, and diode D4 outputs a low-level control signal RLY_L. When the output current of the smart socket to the load is overcurrent, that is, when the output voltage of operational amplifier U1A is greater than 2.85V, the voltage of the non-inverting input of comparator U2A is greater than the voltage of the inverting input, and the output of comparator U2A outputs a high level. The voltage of the non-inverting input of comparator U2A is pulled above 2.85V by diode D1, thereby locking the output level of comparator U2A at a high level. Diode D4 outputs a high-level control signal RLY_L, which can only be restored after powering off and restarting.

[0044] When the control signal RLY_L is low, transistor Q1 is not conducting, and the gate of MOS transistor Q2 is high, driving MOS transistor Q2 to close and conduct. That is, relay RLY1 is closed by default after power is turned on. When the smart socket has overcurrent, the control signal RLY_L is high, transistor Q1 is turned on, pulling down the gate level of MOS transistor Q2, making MOS transistor Q2 non-conducting and relay RLY1 popping open, thereby protecting the smart socket from damage.

[0045] Different from the existing technology, the embodiment of the present invention provides an overcurrent latch module for detecting the output current, and outputs a control signal when the smart socket overcurrent occurs, so that the control module disconnects the power supply circuit of the smart socket, which can effectively realize overcurrent detection and protection of the smart socket, improve the reliability of the smart socket, and reduce costs.

[0046] Furthermore, the embodiment of the present application also provides another overcurrent protection circuit for smart sockets, the structural diagram of which is shown in FIG. Figure 6 As shown, the overcurrent protection circuit applied to the smart socket includes an overcurrent latch module 100, a control module 200 and an overtemperature latch module 300. The control module 200 is connected to the overtemperature latch module 300, the overcurrent latch module 100, the input power supply 20 and the smart socket 30 respectively.

[0047] The functions of the overcurrent latch module 100 and the control module 200 have been described in the above embodiments and will not be repeated here. The overtemperature latch module 300 outputs a low-level control signal when the operating temperature of the smart socket 30 is less than a preset temperature. It is also configured to output and latch a high-level control signal when the operating temperature of the smart socket 30 is greater than the preset temperature. By way of example and not limitation, the preset temperature may be 90 degrees Celsius. When the operating temperature of the smart socket 30 is less than 90 degrees Celsius, the overtemperature latch module 300 outputs a low-level control signal; when the operating temperature of the smart socket 30 is greater than 90 degrees Celsius, the overtemperature latch module 300 outputs and latches a high-level control signal.

[0048] It should be noted that the latching is implemented in the following manner: the over-temperature latch module 300 forms a positive feedback loop with the control signal as a feedback signal, so as to latch the high-level control signal when the control signal is at a high level.

[0049] The over-temperature latch module 300 is combined with the control module 200 to disconnect the power supply circuit between the input power source 20 and the smart socket 30 when the operating temperature of the smart socket 30 is greater than a preset temperature.

[0050] In some embodiments of the present application, the structural diagram of the over-temperature latch module 300 is as follows: Figure 7 As shown, the over-temperature latch module 300 includes a temperature driving unit 310 and an output feedback unit 320. The output feedback unit 320 is connected to the temperature driving unit 310 and the control module 200 respectively. The temperature driving unit 310 is also connected to the first power supply 40.

[0051] The temperature drive unit 310 is configured to output a drive voltage responsive to the operating temperature under the influence of the output voltage of the first power supply 40. This can be implemented by a temperature sensor, powered by the first power supply, and whose output signal changes in response to changes in the operating environment. By way of example and not limitation, the temperature sensor is a thermistor, which can be either a positive temperature coefficient thermistor or a negative temperature coefficient thermistor.

[0052] In the embodiment of the present application, when the operating temperature is lower than the preset temperature, the driving voltage is lower than the preset reference voltage; when the operating temperature is higher than the preset temperature, the driving voltage is higher than the preset reference voltage.

[0053] In some embodiments of the present application, the circuit schematic diagram of the over-temperature latch module 300 is as follows: Figure 8 As shown, the temperature driving unit 310 includes a thermistor RT1, a resistor R12 and a capacitor C8, and the output feedback module 320 includes a comparator U2B, a resistor R10, a resistor R11, a resistor R13, a capacitor C7, a capacitor C9, a diode D2 and a diode D5.

[0054] A first end of the thermistor RT1 is connected to a first power supply (taking +3.3V as an example), a second end of the thermistor RT1 is connected to a first end of a resistor R12, a first end of a capacitor C8, a cathode of a diode D2, and a non-inverting input end of a comparator U2B, and a second end of the resistor R12 and a second end of the capacitor C8 are grounded GND.

[0055] The first end of the resistor R10 is connected to the second power supply (taking +5V as an example), the first end of the resistor R11, and the first end of the capacitor C7. The second end of the resistor R10 is connected to the inverting input terminal of the comparator U2B, the first end of the resistor R13, and the first end of the capacitor C9. The second end of the resistor R11 is connected to the output terminal of the comparator U2B, the anode of the diode D5, and the anode of the diode D2. The cathode of the diode D5 is connected to the input terminal of the control module 200. The second end of the capacitor C7, the second end of the capacitor C9, and the second end of the resistor R13 are grounded GND.

[0056] The specific working principle is as follows: after the smart socket is powered on, the relay RLY1 is automatically closed. After the load is inserted (i.e., the smart socket is connected to the load), when the smart socket is not overheated, the resistance of thermistor RT1 is greater than the resistance of resistor R12, and the voltage at the non-inverting input of comparator U2B is less than 1.65V (at this time, +5V charges capacitor C8, resistor R11 = 10K, capacitor C8 = 100nF, and the time required for capacitor C8 to charge to 1.67V is T = RT = 1ms, and comparator U2B has flipped). The output of comparator U2B outputs a low level, that is, diode D The cathode of diode D5 outputs a low-level control signal RLY_L. When the smart socket overheats, the resistance of thermistor RT1 is less than that of resistor R12, and the voltage at the non-inverting input of comparator U2B exceeds 1.65V. Comparator U2B does not flip, and the output of comparator U2B outputs a high-level voltage. This voltage is pulled above 1.65V by diode D2, thereby locking the output voltage of comparator U2B. That is, the cathode of diode D5 continuously outputs a high-level control signal RLY_L, which can only be restored after power is turned off and on. The specific working principle of the overcurrent latch module has been described in the above embodiment and will not be repeated here.

[0057] When the control signal RLY_L is low, transistor Q1 is off and the gate of MOS transistor Q2 is high, driving MOS transistor Q2 to close and conduct. That is, relay RLY1 is closed by default after power is turned on. When the smart socket is overheated or overcurrent occurs, the control signal RLY_L is high, transistor Q1 is turned on, pulling the gate level of MOS transistor Q2 down, MOS transistor Q2 is off, and relay RLY1 pops open, thereby protecting the smart socket from damage.

[0058] Different from the prior art, the embodiment of the present invention provides an over-temperature latch module for detecting the operating temperature and an over-current latch module for detecting the output current, which output control signals when the smart socket is over-temperature and over-current respectively, so that the control module disconnects the power supply circuit of the smart socket, thereby effectively realizing over-temperature detection, over-current detection and protection of the smart socket, improving the reliability of the smart socket and reducing costs.

[0059] Based on the overcurrent protection circuit applied to the smart socket provided in the above embodiments, the embodiments of the present application further provide a smart socket, which includes the overcurrent protection circuit applied to the smart socket provided in any of the above embodiments.

[0060] It should be noted that the preferred embodiments of the present invention are given in the specification and drawings of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described in this specification. These embodiments do not serve as additional limitations on the content of the present invention. The purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive. In addition, the above-mentioned technical features continue to be combined with each other to form various embodiments not listed above, which are all considered to be within the scope of the description of the present invention; further, it is obvious to those skilled in the art that improvements or changes can be made based on the above description, and all such improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. An overcurrent protection circuit applied to a smart socket, characterized in that: include: Overcurrent latch module and control module, The control module is connected to the overcurrent latch module and the input power supply respectively; The overcurrent latch module is used to output a low-level control signal when the output current of the smart socket is less than a preset current; and is also used to output and latch a high-level control signal when the output current is greater than the preset current; The control module is used to connect the input power supply and the power supply circuit of the smart socket when receiving the low-level control signal; and is also used to disconnect the power supply circuit when receiving the high-level control signal.

2. The circuit according to claim 1, wherein: The overcurrent latch module forms a positive feedback loop with the control signal as a feedback signal, and latches the high-level control signal when the control signal is at a high level.

3. The circuit according to claim 1, wherein: The overcurrent latch module includes a sampling unit, an amplifying unit and a feedback unit, the amplifying unit is connected to the sampling unit and the feedback unit respectively, the feedback unit is connected to the control module, and the sampling unit is connected to the output neutral terminal of the smart socket; The sampling unit is used to output a sampling voltage under the action of the output current; The amplifying unit is used to amplify the sampling voltage and output a driving voltage; The feedback unit forms a positive feedback loop with the control signal as a feedback signal, and the feedback unit is used to output a low-level control signal when the driving voltage is less than a preset reference voltage; further configured to output and latch the high-level control signal when the driving voltage is greater than the preset reference voltage; When the output current is less than the preset current, the driving voltage is less than the preset reference voltage; When the output current is greater than the preset current, the driving voltage is greater than the preset reference voltage.

4. The circuit according to claim 3, characterized in that The feedback unit is further configured to output the high-level control signal when the level of the control signal is greater than the preset reference voltage.

5. The circuit according to claim 1, wherein: The control module includes a switch drive unit and a relay unit, the relay unit is connected to the input power supply and the switch drive unit respectively, and the switch drive unit is connected to the overcurrent latch module; The switch driving unit is used to output a low-level switch signal under the action of the high-level control signal, and is used to output a high-level switch signal under the action of the low-level control signal; The relay unit is used to turn on the power supply circuit when the conduction signal is at a high level, and is used to turn off the power supply circuit when the conduction signal is at a low level.

6. The circuit according to claim 3, characterized in that The sampling unit includes a resistor R5, and the amplifying unit includes a resistor R3, a resistor R4, a resistor R6, a resistor R9, a capacitor C2, a capacitor C3, a capacitor C6 and an operational amplifier U1A. The first end of the resistor R5 and the first end of the resistor R4 are grounded, the second end of the resistor R5 is connected to the output neutral terminal of the smart socket and the first end of the resistor R6, the first end of the capacitor C2 is connected to the first end of the resistor R3 and a third power supply, and the second end of the resistor R3 is connected to the non-inverting input terminal of the operational amplifier U1A, the second end of the resistor R4, and the second end of the capacitor C2; The second end of the resistor R6 is connected to the inverting input end of the operational amplifier U1A, the first end of the resistor R9 and the first end of the capacitor C6, the first power input end of the operational amplifier U1A is connected to the second power supply and the first end of the capacitor C3, the second end of the resistor R9 is connected to the second end of the capacitor C6, the output end of the operational amplifier U1A and the input end of the feedback unit, and the second end of the capacitor C3 and the second power input end of the operational amplifier U1A are grounded.

7. The circuit according to claim 3, characterized in that The feedback unit includes a comparator U2A, a resistor R1, a resistor R2, a resistor R7, a resistor R8, a capacitor C1, a capacitor C4, a capacitor C5, a diode D1 and a diode D4. The first power input terminal of the comparator U2A is connected to the second power supply, the first end of the capacitor C1, the first end of the resistor R2, and the first end of the resistor R1; the inverting input terminal of the comparator U2A is connected to the second end of the resistor R1, the first end of the resistor R8, and the first end of the capacitor C5; the non-inverting input terminal of the comparator U2A is connected to the first end of the resistor R7, the first end of the capacitor C4, the cathode of the diode D1, and the output terminal of the amplifying unit; The output end of the comparator U2A is connected to the second end of the resistor R2, the anode of the diode D4 and the anode of the diode D1, the cathode of the diode D4 is connected to the input end of the control module, and the second end of the capacitor C1, the second power input end of the comparator U2A, the second end of the resistor R8, the second end of the capacitor C5, the second end of the resistor R7 and the second end of the capacitor C4 are grounded.

8. The circuit according to claim 5, characterized in that The switch driving unit includes a transistor Q1, a resistor R14, a resistor R15, a resistor R16, a resistor R17 and a capacitor C10. The base of the transistor Q1 is connected to the first end of the resistor R17, the first end of the capacitor C10, and the first end of the resistor R15. The second end of the resistor R15 is connected to the output end of the overcurrent latch module. The first end of the resistor R14 is connected to the third power supply. The second end of the resistor R14 is connected to the first end of the resistor R16, the collector of the transistor Q1, and the signal input end of the relay unit. The emitter of the transistor Q1, the second end of the resistor R17, the second end of the capacitor C10, and the second end of the resistor R16 are grounded.

9. The circuit according to claim 5, characterized in that The relay unit includes a MOS tube Q2, a diode D3 and a relay RLY1. The drain of the MOS transistor Q2 is connected to the anode of the diode D3 and the first coil end of the relay RLY1, the gate of the MOS transistor Q2 is connected to the output end of the switch driving unit, and the source of the MOS transistor Q2 is grounded; The cathode of the diode D3 is connected to the second coil end of the relay RLY1 , ​​the first connection end of the relay RLY1 is connected to the input power supply, and the second connection end of the relay RLY1 is connected to the output live wire end of the smart socket.

10. A smart socket, characterized in that: include: An overcurrent protection circuit for a smart socket as claimed in any one of claims 1 to 9.

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