Power-off self-discharge circuit

Abstract

The utility model provides a power-off self-discharge circuit. The power-off self-discharge circuit comprises a power-off self-discharge control module, a load module and an electrolytic capacitor, the power supply input end of the power-off self-discharge control module is used for being connected with a power supply; the discharge end of the power-off self-discharge control module is connected with the negative electrode of the electrolytic capacitor; the power output end of the power-off self-discharge control module is connected with the input end of the load module and the positive electrode of the electrolytic capacitor. A power output end in the power-off self-discharge control module is in gating connection with a power input end or a discharge end; the control end of the power-off self-discharge control module is used for being connected with a standby control pin, gating the discharge end according to a power-off signal generated by the standby control pin, and gating the power supply end according to a power-on signal generated by the standby control pin. When power is off, the discharge end and the electrolytic capacitor form a discharge loop to discharge the electrolytic capacitor, and when the circuit works normally, the power supply end and the electrolytic capacitor form a working loop, so that standby power consumption is effectively reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of circuit discharge, in particular to a power-off self-discharge circuit. Background Art

[0002] At present, the capacity of electrolytic capacitors in some circuits is relatively high. When the circuit is running, the amount of electricity stored in the electrolytic capacitor is relatively large, so that after the product is powered off, there is still high voltage at both ends of the electrolytic capacitor, which poses risks in the subsequent production, assembly and use, and there is a phenomenon of discharge afterglow for the back-end load. Therefore, it is necessary to set up a discharge circuit to amplify the electrolytic capacitor.

[0003] However, the existing discharge circuits all discharge while increasing the circuit's own losses, such as discharging the electrolytic capacitor by placing a discharge resistor or other active discharge circuits. Therefore, the existing discharge circuits cannot be used in circuits with high standby power consumption requirements. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a power-off self-discharging circuit, which can quickly discharge the electrolytic capacitor and effectively reduce the standby power consumption.

[0005] In order to solve the above technical problems, the technical solution adopted by the utility model is:

[0006] A power-off self-discharge circuit comprises a power-off self-discharge control module, a load module and an electrolytic capacitor; the power input terminal of the power-off self-discharge control module is used to connect to a power source; the discharge terminal of the power-off self-discharge control module is connected to the negative electrode of the electrolytic capacitor; the power output terminal of the power-off self-discharge control module is connected to the input terminal of the load module and the positive electrode of the electrolytic capacitor; the power output terminal inside the power-off self-discharge control module is connected to the power input terminal or the discharge terminal through selection; the control terminal of the power-off self-discharge control module is used to connect to a standby control pin, and the discharge terminal is selected according to a power-off signal generated by the standby control pin, and the power terminal is selected according to a power-on signal generated by the standby control pin.

[0007] Furthermore, the power-off self-discharge control module includes a relay, a first transistor and a first resistor; the base of the first transistor is used to connect to the standby control pin; the emitter of the first transistor is respectively connected to one end of the first resistor and the negative electrode of the electrolytic capacitor; the collector of the first transistor is connected to the control end of the relay; the other end of the first resistor is connected to the first path end of the relay as the discharge end; the second path end of the relay is used to connect to the power supply as the power input end; the power output end of the relay is connected to the input end of the load module and the positive electrode of the electrolytic capacitor; the power supply end of the relay is used to connect to the power supply; the power supply end of the relay and the control end are connected inside the relay through a coil.

[0008] Furthermore, the power-off self-discharge control module also includes a second resistor, a third resistor and a protection diode; one end of the second resistor is respectively connected to the base of the first transistor and one end of the third resistor, and the other end of the second resistor is used to connect to the standby control pin; the other end of the third resistor is connected to the emitter of the first transistor; the cathode of the protection diode is connected to the power supply end of the relay, and the anode of the protection diode is connected to the collector of the first transistor.

[0009] Furthermore, it also includes a rectifier module, an intelligent control module and a power supply module; the input end of the rectifier module is used to connect to the power supply, and the output end of the rectifier module is respectively connected to the second path end of the relay and the input end of the power supply module; the first output end of the power supply module is connected to the power input end of the intelligent control module; the second output end of the power supply module is connected to the power supply end of the relay; the standby control end of the intelligent control module is connected to the base of the first transistor.

[0010] Furthermore, the power supply module includes a first power supply unit and a second power supply unit, the first power supply unit and the second power supply unit output different voltages; the output end of the rectifier module is respectively connected to the input end of the first power supply unit and the input end of the second power supply unit; the output end of the first power supply unit is connected to the power input end of the intelligent control module; the output end of the second power supply unit is connected to the power supply end of the relay.

[0011] Furthermore, the first power supply module includes a first step-down constant voltage chip, and the output voltage of the first step-down constant voltage chip corresponds to the input voltage of the intelligent control module; the power input end of the first step-down constant voltage chip is connected to the output end of the rectifier module; the output end of the first step-down constant voltage chip is connected to the power input end of the intelligent control module.

[0012] Furthermore, the second power supply module includes a second step-down constant voltage chip, and the output voltage of the second step-down constant voltage chip corresponds to the power supply voltage of the relay; the power input end of the second step-down constant voltage chip is connected to the output end of the rectifier module; the output end of the second step-down constant voltage chip is connected to the power supply end of the relay.

[0013] Furthermore, the rectifier module includes a rectifier bridge stack and a π-shaped filter unit; the input end of the rectifier bridge stack is used to connect to a power supply; the output end of the rectifier bridge stack is connected to the input end of the π-shaped filter unit; the output end of the π-shaped filter unit is respectively connected to the second path end of the relay and the input end of the power module.

[0014] Furthermore, the intelligent control module includes a microcontroller; a power pin of the microcontroller is connected to the first output end of the power module; and an enable pin of the microcontroller is connected to the base of the first transistor.

[0015] Furthermore, the load module includes a light-emitting diode and an LED chip; the power output end of the power-off self-discharge control module is respectively connected to the positive electrode of the light-emitting diode and the power supply end of the LED chip; the output end of the LED chip is connected to the negative electrode of the light-emitting diode.

[0016] The beneficial effect of the utility model lies in that the power output end of the power-off self-discharge control module is connected to the positive electrode of the electrolytic capacitor, and the power input end is connected to the power supply and the discharge end is connected to the electrolytic capacitor, and the discharge end circuit or the power supply end circuit is selected based on the received power-off signal and the power-on signal, so that when the power is off, the discharge end and the electrolytic capacitor form a discharge circuit to discharge the electrolytic capacitor, and when the circuit works normally, the power supply end and the electrolytic capacitor form a working circuit, which will not increase the power consumption of the circuit, realize rapid discharge of the electrolytic capacitor, and effectively reduce the standby power consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of a module of a power-off self-discharging circuit in this embodiment;

[0018] Figure 2 This is a schematic diagram of the first circuit connection of a power-off self-discharging circuit in this embodiment;

[0019] Figure 3 This is a circuit connection diagram of a power module in a power-off self-discharging circuit in this embodiment;

[0020] Description of labels:

[0021] 1. Power-off self-discharge control module; 2. Load module; 3. Rectification module; 4. Intelligent control module; 5. Power module; 51. First power supply unit; 52. Second power supply unit;

[0022] E1, electrolytic capacitor; BR1, rectifier bridge stack; relay1, relay; V1, first transistor; R12, first resistor; R13, second resistor; R14, third resistor; D8, protection diode; IC4, LED chip; MK1, microcontroller; IC2, first step-down constant voltage chip; IC3, second step-down constant voltage chip. DETAILED DESCRIPTION

[0023] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in conjunction with the implementation modes and the accompanying drawings.

[0024] A power-off self-discharge circuit comprises a power-off self-discharge control module, a load module and an electrolytic capacitor; the power input terminal of the power-off self-discharge control module is used to connect to a power source; the discharge terminal of the power-off self-discharge control module is connected to the negative electrode of the electrolytic capacitor; the power output terminal of the power-off self-discharge control module is connected to the input terminal of the load module and the positive electrode of the electrolytic capacitor; the power output terminal inside the power-off self-discharge control module is connected to the power input terminal or the discharge terminal through selection; the control terminal of the power-off self-discharge control module is used to connect to a standby control pin, and the discharge terminal is selected according to a power-off signal generated by the standby control pin, and the power terminal is selected according to a power-on signal generated by the standby control pin.

[0025] From the above description, it can be seen that the beneficial effect of the utility model is that: by connecting the power output end of the power-off self-discharge control module to the positive pole of the electrolytic capacitor, and connecting its power input end to the power supply and connecting the discharge end to the electrolytic capacitor, and selecting the discharge end circuit or the power supply end circuit based on the received power-off signal and power-on signal, when the power is off, the discharge end and the electrolytic capacitor form a discharge circuit to discharge the electrolytic capacitor, and when the circuit works normally, the power supply end and the electrolytic capacitor form a working circuit, which will not increase the power consumption of the circuit, achieve rapid discharge of the electrolytic capacitor, and effectively reduce standby power consumption.

[0026] Furthermore, the power-off self-discharge control module includes a relay, a first transistor and a first resistor; the base of the first transistor is used to connect to the standby control pin; the emitter of the first transistor is respectively connected to one end of the first resistor and the negative electrode of the electrolytic capacitor; the collector of the first transistor is connected to the control end of the relay; the other end of the first resistor is connected to the first path end of the relay as the discharge end; the second path end of the relay is used to connect to the power supply as the power input end; the power output end of the relay is connected to the input end of the load module and the positive electrode of the electrolytic capacitor; the power supply end of the relay is used to connect to the power supply; the power supply end of the relay and the control end are connected inside the relay through a coil.

[0027] It can be seen from the above description that the state of the first transistor is controlled by the power-off signal and the power-on signal. When the circuit is powered on and a high-level signal is generated, the power supply end, the control end and the first transistor of the relay form a loop when the first transistor is turned on, that is, at this time, the second path end of the relay is selected to make the circuit work normally; when the circuit is powered off and a low-level signal is generated, the first transistor is cut off, that is, at this time, the first path end of the relay is selected to discharge the electrolytic capacitor.

[0028] Furthermore, the power-off self-discharge control module also includes a second resistor, a third resistor and a protection diode; one end of the second resistor is respectively connected to the base of the first transistor and one end of the third resistor, and the other end of the second resistor is used to connect to the standby control pin; the other end of the third resistor is connected to the emitter of the first transistor; the cathode of the protection diode is connected to the power supply end of the relay, and the anode of the protection diode is connected to the collector of the first transistor.

[0029] It can be seen from the above description that the second resistor and the third resistor are provided to provide the required voltage for the first transistor, and the peak voltage of the first transistor is absorbed by the protection diode, thereby ensuring the stable operation of the first transistor.

[0030] Furthermore, it also includes a rectifier module, an intelligent control module and a power supply module; the input end of the rectifier module is used to connect to the power supply, and the output end of the rectifier module is respectively connected to the second path end of the relay and the input end of the power supply module; the first output end of the power supply module is connected to the power input end of the intelligent control module; the second output end of the power supply module is connected to the power supply end of the relay; the standby control end of the intelligent control module is connected to the base of the first transistor.

[0031] From the above description, it can be seen that after the rectifier module is set to convert AC power into DC power, the power module further converts it to power different functional modules; at the same time, the intelligent control module can effectively detect the power supply changes at its power input end and output a control signal to achieve the selection control of the relay.

[0032] Furthermore, the power supply module includes a first power supply unit and a second power supply unit, the first power supply unit and the second power supply unit output different voltages; the output end of the rectifier module is respectively connected to the input end of the first power supply unit and the input end of the second power supply unit; the output end of the first power supply unit is connected to the power input end of the intelligent control module; the output end of the second power supply unit is connected to the power supply end of the relay.

[0033] It can be seen from the above description that by outputting different voltages from the first power supply unit and the second power supply unit, the voltage requirements of different functional modules can be met.

[0034] Furthermore, the first power supply module includes a first step-down constant voltage chip, and the output voltage of the first step-down constant voltage chip corresponds to the input voltage of the intelligent control module; the power input end of the first step-down constant voltage chip is connected to the output end of the rectifier module; the output end of the first step-down constant voltage chip is connected to the power input end of the intelligent control module.

[0035] It can be seen from the above description that the output voltage of the first step-down constant voltage chip corresponds to the input voltage of the intelligent control module, thereby being able to provide a stable voltage output for the intelligent control module.

[0036] Furthermore, the second power supply module includes a second step-down constant voltage chip, and the output voltage of the second step-down constant voltage chip corresponds to the power supply voltage of the relay; the power input end of the second step-down constant voltage chip is connected to the output end of the rectifier module; the output end of the second step-down constant voltage chip is connected to the power supply end of the relay.

[0037] It can be seen from the above description that the output voltage of the second step-down constant voltage chip corresponds to the power supply voltage of the relay, thereby being able to provide a stable voltage output for the relay.

[0038] Furthermore, the rectifier module includes a rectifier bridge stack and a π-shaped filter unit; the input end of the rectifier bridge stack is used to connect to a power supply; the output end of the rectifier bridge stack is connected to the input end of the π-shaped filter unit; the output end of the π-shaped filter unit is respectively connected to the second path end of the relay and the input end of the power module.

[0039] From the above description, it can be seen that after the mains power is converted into direct current by the rectifier bridge, it is filtered by the π-shaped filter unit to eliminate the residual AC signal.

[0040] Furthermore, the intelligent control module includes a microcontroller; a power pin of the microcontroller is connected to the first output end of the power module; and an enable pin of the microcontroller is connected to the base of the first transistor.

[0041] From the above description, it can be seen that a microcontroller is used as the intelligent control module. The microcontroller can more accurately detect the power supply changes of its power supply pins and output a control signal to achieve the gating control of the relay.

[0042] Furthermore, the load module includes a light-emitting diode and an LED chip; the power output end of the power-off self-discharge control module is respectively connected to the positive electrode of the light-emitting diode and the power supply end of the LED chip; the output end of the LED chip is connected to the negative electrode of the light-emitting diode.

[0043] It can be seen from the above description that the light emitting diode and the LED chip are used as a load module so that the circuit can be applied to lighting scenes.

[0044] The power-off self-discharging circuit provided by the utility model can be applied to smart home appliance scenarios such as LED circuits, and is described below through specific implementation methods:

[0045] Embodiment 1

[0046] Please refer to Figure 1 In this embodiment, the power-off self-discharge circuit is applied to the LED intelligent circuit scene; it includes a power-off self-discharge control module 1, a load module 2, a rectifier module 3, an intelligent control module 4 and a power module 5; wherein the power module 5 includes a first power unit 51 and a second power unit 52, and the first power unit 51 and the second power unit 52 output different voltages; in this embodiment, the first power unit 51 is a 3.3V power supply, and the second power unit 52 is a 12V power supply. The specific connection method between the modules is as follows:

[0047] The input end of the rectifier module 3 is used to connect to the mains, that is, input AC power; the output end of the rectifier module 3 is respectively connected to the power input end of the power-off self-discharge control module 1, the input end of the first power supply unit 51 and the input end of the second power supply unit 52; the output end of the first power supply unit 51 is connected to the power input end of the intelligent control module 4; the output end of the second power supply unit 52 is connected to the power supply end of the power-off self-discharge control module 1; the discharge end of the power-off self-discharge control module 1 is connected to the negative electrode of the electrolytic capacitor E1; the power output end of the power-off self-discharge control module 1 is connected to the input end of the load module 2 and the positive electrode of the electrolytic capacitor E1; the power output end inside the power-off self-discharge control module 1 is connected to the power input end or the discharge end; the control end of the power-off self-discharge control module 1 is used to connect to the standby control pin, and the discharge end is selected according to the power-off signal generated by the standby control pin, and the power end is selected according to the power-on signal generated by the standby control pin; the electrolytic capacitor E1 is arranged between the power-off self-discharge control module 1 and the load module 2.

[0048] Please refer to Figure 2 , wherein 1) the rectifier module 3 is used to: convert the AC input voltage into a DC voltage to obtain HV. Specifically: the rectifier module 3 includes a rectifier bridge stack BR1 and a π-shaped filter unit; the input end of the rectifier bridge stack BR1 is used to connect to the power supply; the output end of the rectifier bridge stack BR1 is connected to the input end of the π-shaped filter unit; the output end (HV) of the π-shaped filter unit is respectively connected to the second path end of the relay relay1 and the input end of the power module 5. Among them, the π-shaped filter unit in this embodiment is composed of a capacitor C1, a capacitor C2, a resistor R1 and an inductor L1; at the same time, the input end of the rectifier bridge stack BR1 is also provided with a fuse resistor F1 and a varistor RV1; the output end of the π-shaped filter unit is also provided with an anti-reverse diode D7.

[0049] Its working principle is as follows: when the AC power is connected through the neutral line (N) and the live line (L), the live line end passes through the fuse resistor to one end of the lightning surge varistor and a winding of the common mode transformer T1, and then to an AC input pin of the bridge rectifier device BR1; the neutral line is connected to the other end of the lightning surge varistor and then passes through another winding of the common mode transformer T1, and then to another AC input pin of the bridge rectifier device BR1; after being rectified by the rectifier unit and then passed through the π-shaped filter unit, it is output to the back end, at which point the AC voltage has become a DC voltage HV.

[0050] 2) The power-off self-discharge control module 1 is used to: realize the power-off self-discharge circuit. Specifically: the power-off self-discharge control module 1 includes a relay relay1, a first transistor V1, a first resistor R12, a second resistor R13, a third resistor R14 and a protection diode D8; one end of the second resistor R13 is respectively connected to the base of the first transistor V1 and one end of the third resistor R14, and the other end of the second resistor R13 is connected to the enable pin (i.e., the standby control pin, STB) of the intelligent control module 4; the other end of the third resistor R14 is connected to the emitter of the first transistor V1; the emitter of the first transistor V1 is respectively connected to one end of the first resistor R12 and the negative electrode of the electrolytic capacitor E1; the collector of the first transistor V1 is connected to the control end (pin 2) of the relay relay1; the other end of the first resistor R12 is connected to the base of the relay relay1; the other end of the first resistor R12 is connected to the base of the relay relay1; the collector of the first transistor V1 is connected to the control end (pin 2) ... The first passage end (pin 4) of the relay relay1 is connected to the output end (HV) of the π-shaped filter unit as a discharge end; the second passage end (pin 5) of the relay relay1 is connected to the output end (HV) of the π-shaped filter unit as a power input end; the power output end (pin 3) of the relay relay1 is connected to the input end of the load module 2 and the positive electrode of the electrolytic capacitor E1; the power supply end (pin 1) of the relay relay1 is connected to the output end (12V) of the second power supply unit 52; the power supply end of the relay relay1 and the control end (pin 2) are connected inside the relay relay1 through a coil; the cathode of the protection diode D8 is connected to the power supply end of the relay relay1, and the anode of the protection diode D8 is connected to the collector of the first transistor V1.

[0051] The specific principles are as follows:

[0052] The voltage of HV flows to the 5th pin of relay1 through the anti-reverse diode D7 to wait for the conduction of relay1. When STB receives a high-level signal, the first transistor V1 is turned on; at this time, the 1st and 2nd pins of relay1 receive voltage and start working, so that the 3rd and 4th pins of relay1 change from normally closed to open, and the discharge circuit of electrolytic capacitor E1 is disconnected; at the same time, the 3rd and 5th pins of relay1 change from normally open to connected, and the voltage of HV flows from the 5th pin of relay1 to the 3rd pin, and is filtered by the electrolytic capacitor E1 for energy storage, and supplies power to the subsequent load module 2.

[0053] When STB receives a low-level signal, the first transistor V1 is turned off; at this time, pins 1 and 2 of relay relay1 cannot be conducted, so that pins 3 and 4 of relay relay1 are conducted, that is, the discharge circuit of electrolytic capacitor E1 is conducted; at the same time, pins 3 and 5 of relay relay1 are disconnected, and the subsequent load module 2 cannot be powered.

[0054] 3) Load module 2 is used for: load linear control circuit with LED as load. Specifically: Load module 2 includes a light-emitting diode and an LED chip IC4, the model of LED chip IC4 is BP5758; the power output end (pin 3) of the power-off self-discharge control module is respectively connected to the positive pole of the light-emitting diode and the power supply end (HV) of the LED chip IC4; the output end (OUT) of the LED chip IC4 is connected to the negative pole of the light-emitting diode; the control end (SDA&SCL) of the LED chip IC4 is connected to the control pin (SDA&SCL) of the intelligent control module 4. The specific working principle is as follows: when power is obtained from pin 3 of relay relay1, one path provides positive voltage to each light-emitting diode, and the other path supplies power to the HV pin of LED chip IC4, so that LED chip IC4 enters standby state; the communication protocol pin of LED chip IC4 (SDA&SCL is IIC) is used to receive the signal sent by intelligent control module 4 to control the working status of each channel of LED chip IC4; among them, OUT1 corresponds to LED1, OUT2 corresponds to LED2, OUT3 corresponds to LED3, OUT4 corresponds to LED4, and OUT5 corresponds to LED5.

[0055] 4) The intelligent control module 4 is used to: control the power-off self-discharge control module 1 and the LED load circuit. Specifically: the intelligent control module 4 includes a microcontroller MK1; the power pin (3.3V) of the microcontroller MK1 is connected to the first output end of the power module 5; the enable pin (STB) of the microcontroller MK1 is connected to the base of the first transistor V1. The specific working principle is as follows: when the 3.3V voltage enters the microcontroller MK1, the microcontroller MK1 starts to work. a. In normal working mode, the STB pin outputs a high level to the base of the first transistor V1, and the IIC outputs the corresponding instruction to control the load module 2; b. When in standby mode, the STB pin outputs a low level to the base of the first transistor V1, and the IIC output turns off the load module 2.

[0056] 5) The power module 5 includes:

[0057] Please refer to Figure 3 , the first power supply unit 51 is used to: after being powered by HV, convert HV into a 3.3V power supply circuit. The first power supply module 5 includes a first step-down constant voltage chip IC2, model BP2571; the output voltage of the first step-down constant voltage chip IC2 corresponds to the input voltage of the intelligent control module 4, that is, it provides a 3.3V voltage; the power input end of the first step-down constant voltage chip IC2 is connected to the output end of the rectifier module 3; the output end of the first step-down constant voltage chip IC2 is connected to the power input end of the intelligent control module 4. The specific working principle is as follows:

[0058] This circuit is a buck voltage stabilization circuit; after being powered by HV, the first buck type constant voltage chip IC2 is powered through the anti-reverse isolation diode D5; the diode D5 supplies power to the capacitor E4 for energy storage on one side and supplies power to the chip on the other side; after the chip is powered, the internal operation starts, and the output from the 2nd pin of the chip is filtered through the energy storage capacitor E5 to provide a 3.3V power supply voltage for the subsequent circuit; wherein, the module also includes a 3.3V energy storage conversion inductor L3, a current sampling resistor R26, a resistor R27, a dummy load R25 and other components and the first buck type constant voltage chip IC2 to form a complete buck 3.3V system.

[0059] The second power supply unit 52 is used to convert HV into a 12V power supply circuit after being powered by HV. The second power supply module 5 includes a second step-down constant voltage chip IC3, model BP2522; and the output voltage of the second step-down constant voltage chip IC3 corresponds to the power supply voltage of the relay relay1, that is, providing a 12V voltage; the power input end of the second step-down constant voltage chip IC3 is connected to the output end of the rectifier module 3; the output end of the second step-down constant voltage chip IC3 is connected to the power supply end of the relay relay1. The specific working principle is as follows: after being powered by HV, it enters the 4th pin of the second step-down constant voltage chip IC3 through the anti-reverse isolation diode D4 and the energy storage filter E2 in turn, so that the entire system in the second step-down constant voltage chip IC3 works, and outputs a stable 12V power supply voltage to power the subsequent circuits; this 12V power supply circuit also includes a 12V buck (BUCK) circuit composed of a storage filter capacitor E2, a power supply filter capacitor C10, a current sampling resistor R21 and a sampling resistor R3, a freewheeling diode D6, an energy storage conversion inductor L2, a dummy load R19, an output filter capacitor E3 and an anti-interference diode D11 in conjunction with the second step-down constant voltage chip IC3.

[0060] The working principle of the above power-off self-discharge circuit is as follows:

[0061] 1. Normal working status:

[0062] When the mains power is connected, the entire circuit enters the power supply state; at this time, the intelligent control module 4 starts to work after receiving power; the STB pin outputs a high level, connecting the 3rd and 5th pins of relay 1 to supply power to the LED load; at the same time, the IIC of the intelligent control module 4 also outputs a signal to control the working state of the LED load.

[0063] 2. Power-off self-discharge state:

[0064] When the mains is turned off, the HV is powered off, cutting off the power to the intelligent control module 4; the STB pin has no output and is in a low level state, so that the third and fourth pins of the relay relay1 are connected; at the same time, the LED load circuit is also turned off for consumption, and the energy stored at both ends of the electrolytic capacitor E1 cannot be discharged; since there is a time difference in the closing of the LED load circuit, afterglow will be generated, but the third and fourth pins of the relay relay1 are connected, the electrolytic capacitor E1 can discharge the first resistor R12 through the third and fourth pins of the relay relay1, so that the charge stored in the electrolytic capacitor E1 is quickly released, and no LED afterglow is generated.

[0065] 3. Standby and hibernation state:

[0066] When the product needs to be in a sleep standby state in order to save electricity, the STB pin of the intelligent control module 4 outputs a low level to connect the third and fourth pins of the relay relay1; the electrolytic capacitor E1 discharges the first resistor R12 through the third and fourth pins of the relay relay1, without consuming any energy for the circuit; at the same time, the relay relay1 stops supplying power to the load circuit, that is, the LED load circuit does not consume electrical energy; the first and second pins of the second power supply unit 52 relay relay1 are not connected to the ground, and the second power supply unit 52 cannot supply power to further reduce circuit losses, thereby reducing all losses of the overall circuit to meet the low energy consumption requirements.

[0067] The above description is only an embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent transformations made using the contents of the specification and drawings of the present invention, or directly or indirectly applied in the relevant technical field, are also included in the patent protection scope of the present invention.

Claims

1. A power-off self-discharge circuit, characterized in that: It includes a power-off self-discharge control module, a load module, and an electrolytic capacitor; The power input terminal of the power-off self-discharge control module is used to connect to a power source; The discharge end of the power-off self-discharge control module is connected to the negative electrode of the electrolytic capacitor; The power output end of the power-off self-discharge control module is connected to the input end of the load module and the positive electrode of the electrolytic capacitor; The power output terminal inside the power-off self-discharge control module is strobed connected to the power input terminal or the discharge terminal; The control end of the power-off self-discharge control module is used to connect to the standby control pin, and to enable the discharge end according to the power-off signal generated by the standby control pin, and to enable the power input end according to the power-on signal generated by the standby control pin.

2. A power-off self-discharge circuit according to claim 1, characterized in that: The power-off self-discharge control module includes a relay, a first transistor and a first resistor; The base of the first transistor is used to be connected to the standby control pin; The emitter of the first transistor is connected to one end of the first resistor and the negative electrode of the electrolytic capacitor respectively; The collector of the first transistor is connected to the control end of the relay; The other end of the first resistor is connected to the first path end of the relay as the discharge end; The second path end of the relay is used to be connected to a power source and serves as the power input end; The power output end of the relay is connected to the input end of the load module and the positive electrode of the electrolytic capacitor; The power supply end of the relay is used to be connected to a power supply; The power supply end and the control end of the relay are connected inside the relay through a coil.

3. A power-off self-discharge circuit according to claim 2, characterized in that: The power-off self-discharge control module also includes a second resistor, a third resistor and a protection diode; One end of the second resistor is connected to the base of the first transistor and one end of the third resistor respectively, and the other end of the second resistor is used to be connected to the standby control pin; The other end of the third resistor is connected to the emitter of the first transistor; The cathode of the protection diode is connected to the power supply end of the relay, and the anode of the protection diode is connected to the collector of the first transistor.

4. A power-off self-discharge circuit according to claim 2, characterized in that: It also includes a rectifier module, an intelligent control module and a power module; The input end of the rectifier module is used to connect to the power supply, and the output end of the rectifier module is respectively connected to the second path end of the relay and the input end of the power supply module; The first output terminal of the power module is connected to the power input terminal of the intelligent control module; The second output terminal of the power module is connected to the power supply terminal of the relay; The standby control terminal of the intelligent control module is connected to the base of the first transistor.

5. A power-off self-discharge circuit according to claim 4, characterized in that: The power supply module includes a first power supply unit and a second power supply unit, and the first power supply unit and the second power supply unit output different voltages; The output end of the rectifier module is connected to the input end of the first power supply unit and the input end of the second power supply unit respectively; The output end of the first power supply unit is connected to the power input end of the intelligent control module; The output end of the second power supply unit is connected to the power supply end of the relay.

6. A power-off self-discharge circuit according to claim 5, characterized in that: The first power supply unit includes a first step-down constant voltage chip, and the output voltage of the first step-down constant voltage chip corresponds to the input voltage of the intelligent control module; The power input end of the first step-down constant voltage chip is connected to the output end of the rectifier module; The output end of the first step-down constant voltage chip is connected to the power input end of the intelligent control module.

7. A power-off self-discharging circuit according to claim 5, characterized in that: The second power supply unit includes a second step-down constant voltage chip, and the output voltage of the second step-down constant voltage chip corresponds to the power supply voltage of the relay; The power input end of the second step-down constant voltage chip is connected to the output end of the rectifier module; The output end of the second step-down constant voltage chip is connected to the power supply end of the relay.

8. A power-off self-discharging circuit according to claim 4, characterized in that: The rectifier module includes a rectifier bridge stack and a π-shaped filter unit; The input end of the rectifier bridge stack is used to be connected to a power source; The output end of the rectifier bridge stack is connected to the input end of the π-shaped filter unit; The output end of the π-shaped filter unit is connected to the second passage end of the relay and the input end of the power module respectively.

9. A power-off self-discharging circuit according to claim 4, characterized in that: The intelligent control module includes a microcontroller; The power pin of the microcontroller is connected to the first output terminal of the power module; The enable pin of the microcontroller is connected to the base of the first transistor.

10. The power-off self-discharging circuit according to claim 4, characterized in that: The load module includes a light emitting diode and an LED chip; The power output end of the power-off self-discharge control module is respectively connected to the positive electrode of the light-emitting diode and the power supply end of the LED chip; The output end of the LED chip is connected to the cathode of the light emitting diode.

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