LED module control circuit

Abstract

The utility model relates to the technical field of LED control, and discloses an LED module control circuit with higher safety and reliability, which comprises a switch circuit (110), an input voltage detection circuit (120), an LED drive circuit (130), a magnetic induction detection circuit (160) and a master control circuit (170), when the magnetic induction detection circuit (160) does not sense a magnetic induction signal, the output control signal is a high level, and when the magnetic induction signal is not sensed, the output control signal is a low level. The switching circuit (110) is controlled to be conducted so as to control the LED module (140) to work; when the magnetic induction detection circuit (160) senses a magnetic induction signal, the main control circuit (170) reduces the duty ratio of a pulse signal so as to reduce the brightness of the LED module (140). And when the feedback voltage signal is lower than the preset value, the output control signal is low level, and the switching circuit (110) is controlled to be switched off.

Description

TECHNICAL FIELD

[0001] The utility model relates to LED control technical field, more specifically, relate to a kind of LED module control circuit. BACKGROUND

[0002] Semiconductor light-emitting diode (LED) as light source has advantages in output, efficiency or reliability. Therefore, actively research and development LED as high output and high efficiency light source, to replace the backlight of light emitting device or display device. Usually, drive LED with low driving current, in order to with ordinary voltage (i.e., 220V AC drive, power supply voltage greatly exceeds human safety voltage, its insulation withstand voltage, leakage current, insulation resistance is out of standard, and it is very inconvenient to use;

[0003] Of course there is also the use of low voltage input, but the user carries when not considering the safety circuit filter inside, when user triggers start switch under the condition of inattentive, since LED generates high temperature when working, this can greatly reduce the life of LED product, and there is the possibility of endangering personal safety.

[0004] Therefore, how to ensure that when mis-triggering, brightness can be automatically adjusted or automatically shut down in high temperature state, to improve the life of LED product and the safety of use become the technical problems that the person skilled in the art needs to solve. CONTENT OF UTILITY MODEL

[0005] The technical problem to be solved by the utility model is that, in view of the defect that the safety circuit is not considered when the user carries in the prior art, when the user triggers the start switch under the condition of inattentive, since LED generates high temperature when working, this can greatly reduce the life of LED product, and there is the possibility of endangering personal safety. Provide a kind of LED module control circuit with higher safety and reliability.

[0006] The technical scheme adopted by the utility model to solve its technical problems is: a kind of LED module control circuit is constructed, with:

[0007] Switching circuit, it is configured in control circuit, its input end is used to receive low voltage direct current signal;

[0008] Input voltage detection circuit, its input end is coupled to the output end of the switching circuit, for obtaining voltage signal;

[0009] LED drive circuit, its input end is coupled to the output end of the switching circuit, for obtaining the direct current signal, the direct current signal is used to trigger LED module;

[0010] Magnetic induction detection circuit, its input end is used to obtain the magnetic induction signal formed by shell magnet;

[0011] A main control circuit is configured to output at least one control signal and a pulse signal, wherein

[0012] A signal input end of the main control circuit is connected with an output end of the magnetic induction detection circuit, configured to receive the magnetic induction signal,

[0013] A voltage feedback end of the main control circuit is connected with an output end of the input voltage detection circuit, configured to receive the voltage signal,

[0014] A signal output end of the main control circuit is connected with a signal input end of the switch circuit, configured to receive the control signal,

[0015] Another signal output end of the main control circuit is connected with a signal input end of the LED driving circuit, configured to receive the pulse signal,

[0016] When the magnetic induction detection circuit does not induce the magnetic induction signal, the output control signal is high level, and the switch circuit is controlled to be turned on to control the LED module to work;

[0017] When the magnetic induction detection circuit induces the magnetic induction signal, the main control circuit reduces the duty cycle of the pulse signal to reduce the brightness of the LED module;

[0018] When the feedback voltage signal is lower than a preset value, the output control signal is low level, and the switch circuit is controlled to be turned off.

[0019] In some embodiments, the switch circuit at least includes a first MOS tube and a first triode,

[0020] A source of the first MOS tube is connected with an output side of a power supply through a second diode, configured to receive a low-voltage direct current signal,

[0021] A drain of the first MOS tube is connected with input ends of the input voltage detection circuit and the LED driving circuit respectively,

[0022] A gate of the first MOS tube is connected with a collector of the first triode through a ninth resistor,

[0023] A base of the first triode is connected with a signal output end of the main control circuit through a fourteenth resistor,

[0024] An emitter of the first triode is connected with a common end.

[0025] In some embodiments, the switch circuit further includes a touch switch,

[0026] One end of the touch switch is connected with a gate of the first MOS tube through a fourth diode,

[0027] The other end of the microswitch is connected to a signal output terminal of the main control circuit through a third diode.

[0028] In some embodiments, the input voltage detection circuit comprises a thirteenth resistor, a seventeenth resistor and a seventh capacitor,

[0029] The thirteenth resistor and the seventeenth resistor are connected in series and then connected in parallel with the seventh capacitor,

[0030] One end of the thirteenth resistor is used to obtain the voltage signal,

[0031] The connection end of the seventeenth resistor and the seventh capacitor is connected to a voltage feedback terminal of the main control circuit.

[0032] In some embodiments, the LED driving circuit comprises at least a driver, a second triode, a third triode and a second MOS tube,

[0033] The power supply end of the driver is connected to the drain of the first MOS tube,

[0034] The base of the second triode is connected to the drain of the first MOS tube through a twenty-third resistor,

[0035] The collector of the second triode is connected to the input end of the driver,

[0036] The base of the third triode is connected to another signal output terminal of the main control circuit through a sixteenth resistor,

[0037] The collector of the third triode is coupled to the base of the second triode,

[0038] The gate of the second MOS tube is connected to the output end of the driver,

[0039] The drain of the second MOS tube is connected to the current sampling end of the driver and the positive pole of the LED module through a first inductor,

[0040] The emitter of the second triode, the emitter of the third triode and the source of the second MOS tube are respectively connected to a common terminal.

[0041] In some embodiments, the magnetic induction detection circuit comprises at least a magnetic sensor,

[0042] The input end of the magnetic sensor is used to obtain the magnetic induction signal formed by the shell magnet,

[0043] The output end of the magnetic sensor is connected to a signal input terminal of the main control circuit for receiving the magnetic induction signal.

[0044] In some embodiments, the main control circuit comprises at least a main controller,

[0045] A signal input end of the main controller is connected with an output end of the magnetic sensor, for receiving the magnetic induction signal,

[0046] A voltage feedback end of the main controller is connected with one end of the seventh capacitor, for receiving the voltage signal,

[0047] A signal output end of the main controller is connected with a base of the first triode, and the first triode is used for receiving the control signal,

[0048] Another signal output end of the main controller is connected with a base of the third triode, and the third triode is used for receiving the pulse signal.

[0049] In some embodiments, the first triode, the second triode and the third triode are selected as NPN type triodes,

[0050] The first MOS tube is selected as a P-channel MOS tube,

[0051] The second MOS tube is selected as an N-channel MOS tube.

[0052] In the LED module control circuit, the magnetic induction detection circuit obtains the magnetic induction signal formed by the shell magnet, the main control circuit processes the magnetic induction signal to determine whether the LED flashlight is in a false triggering state, when the magnetic induction detection circuit senses the magnetic induction signal, the main control circuit reduces the duty cycle of the pulse signal to reduce the brightness of the LED module, thereby automatically adjusting the brightness to reduce the temperature, when the feedback voltage signal is lower than the preset value, the output control signal is low, and the switch circuit is controlled to be turned off, which can effectively solve the high temperature caused by the false opening of the LED flashlight, can automatically adjust the brightness or automatically shut down at high temperature, thereby improving the safety and reliability of product use. BRIEF DESCRIPTION OF DRAWINGS

[0053] The utility model will be described further below in combination with the drawings and examples, and the drawings are as follows:

[0054] Figure 1 It is the frame principle diagram of one embodiment of LED module control circuit provided by the utility model;

[0055] Figure 2a It is the circuit principle diagram of one embodiment of switch circuit provided by the utility model;

[0056] Figure 2b It is the circuit principle diagram of one embodiment of input voltage detection circuit and LED drive circuit provided by the utility model;

[0057] Figure 2c This is a circuit diagram of an embodiment of the LED module provided by this utility model;

[0058] Figure 2d This is a circuit diagram of an embodiment of the low dropout linear voltage regulator module provided by this utility model;

[0059] Figure 2e This is a circuit diagram of an embodiment of the magnetic induction detection circuit and main control circuit provided by this utility model;

[0060] Figure 3 This is a graph showing the relationship between the strength of the LED and the magnetic sensor when it senses the magnet on the outer casing. Detailed Implementation

[0061] To provide a clearer understanding of the technical features, objectives, and effects of this utility model, the specific embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0062] like Figure 1 As shown, in the first embodiment of the LED module control circuit of this utility model, the LED module control circuit 100 includes a switching circuit 110, an input voltage detection circuit 120, an LED driving circuit 130, an LED module 140, a low dropout linear regulator module 150, a magnetic induction detection circuit 160, and a main control circuit 170.

[0063] The switching circuit 110 is used to control the on / off state of the LED module circuit;

[0064] The input voltage detection circuit 120 is used to detect the voltage signal output by the switching circuit 110, divide the voltage signal, and then feed it back to the main control circuit 170.

[0065] LED driver circuit 130 is used to control the on / off state and brightness adjustment of LED module 140;

[0066] The low dropout linear regulator module 150 is used to provide an operating voltage of 3.3V;

[0067] The magnetic induction detection circuit 160 is used to detect the magnetic signal generated when the magnetic shell is closed.

[0068] The main control circuit 170, as the core of the circuit, is responsible for signal reception, comparison, and calculation. It includes a voltage threshold.

[0069] It outputs at least one control signal and one pulse signal, and

[0070] Adjust the duty cycle of the pulse signal (e.g., 100% → 20%) to adjust the brightness of the LED module 140;

[0071] Specifically, the switch circuit 110 is configured in the control circuit, an input end of the switch circuit 110 is configured to receive a low-voltage direct-current signal (13.5-22vdc), and the switch circuit 110 is configured to output the low-voltage direct-current signal to the input voltage detection circuit 120 and the LED driving circuit 130;

[0072] Further, an input end of the input voltage detection circuit 120 is coupled to an output end of the switch circuit 110, the input end of the input voltage detection circuit 120 is configured to obtain the voltage signal (13.5-22vdc), and the input voltage detection circuit 120 is configured to perform voltage division on the voltage signal and output the voltage signal to the main control circuit 170;

[0073] An input end of the LED driving circuit 130 is coupled to an output end of the switch circuit 110, the input end of the LED driving circuit 130 is configured to obtain the direct-current signal (13.5-22vdc), and the direct-current signal input to the LED driving circuit 130 is configured to trigger the LED module 140;

[0074] The magnetic induction detection circuit 160 is configured to obtain a magnetic induction signal formed by the shell magnet;

[0075] It can be understood that the shell magnet is combined with the front end of the LED module 140, when the LED lighting product is combined with the magnet cover (for example, the LED module 140 is combined with the cover), and the LED lighting product is mistakenly turned on, at this time, the magnetic induction detection circuit 160 senses the LED lighting device shell magnet, which indicates that the product is in an abnormal working state at this time;

[0076] Further, the main control circuit 170 is configured to output at least one control signal and a pulse signal,

[0077] The main control circuit 170 is configured to receive the magnetic induction signal fed back by the magnetic induction detection circuit 160 through a signal input end of the main control circuit 170 connected with an output end of the magnetic induction detection circuit 160,

[0078] The main control circuit 170 is configured to receive the voltage signal through a voltage feedback end of the main control circuit 170 connected with an output end of the input voltage detection circuit 120,

[0079] The main control circuit 170 is configured to receive the control signal output by the switch circuit 110 through a signal output end of the main control circuit 170 connected with a signal input end of the switch circuit 110,

[0080] The main control circuit 170 is configured to receive the pulse signal through another signal output end of the main control circuit 170 connected with a signal input end of the LED driving circuit 130,

[0081] When the magnetic induction detection circuit 160 does not sense the magnetic induction signal, the output control signal is high level, and the switch circuit 110 is controlled to be turned on to control the LED module 140 to work;

[0082] When the magnetic induction detection circuit 160 senses the magnetic induction signal, the main control circuit 170 reduces the duty cycle of the pulse signal (such as 100%→20%) to reduce the brightness of the LED module 140;

[0083] When the feedback voltage signal is lower than the preset value (such as 13.5VDC), the output control signal is converted from high level to low level, at this time, the switch circuit 110 is controlled to be turned off, and the LED module 140 stops.

[0084] Using the technical solution, the magnetic induction signal formed by the shell magnet is acquired by the magnetic induction detection circuit 160, the magnetic induction signal is processed by the main control circuit 170 to determine whether the LED flashlight is in a false triggering state, when the magnetic induction detection circuit 160 senses the magnetic induction signal, the main control circuit 170 reduces the duty cycle of the pulse signal to reduce the brightness of the LED module 140, thereby automatically adjusting the brightness to reduce the temperature;

[0085] When the feedback voltage signal is lower than the preset value, the output control signal is low level, and the switch circuit 110 is controlled to be turned off, which can effectively solve the high temperature caused by the false opening of the LED flashlight, and can automatically adjust the brightness or automatically shut down at high temperature, thereby improving the safety and reliability of product use

[0086] In some embodiments, as shown in Figure 2a In order to improve the reliability of the on-off of the control circuit, a first MOS tube Q1 and a first triode Q4 can be arranged in the switch circuit 110, wherein the first triode Q4 is selected as an NPN type triode, and the first MOS tube Q1 is selected as a P-channel MOS tube, both of which have the function of switching.

[0087] Specifically, the source of the first MOS tube Q1 is connected with the cathode of the second diode D2, the anode of the second diode D2 is connected with the output side of the power supply (for B+1 end), for receiving a low-voltage direct-current signal (13.5-22vdc),

[0088] The drain of the first MOS tube Q1 is connected with the input end of the input voltage detection circuit 120 and the LED driving circuit 130 respectively, so as to divide the low-voltage direct-current signal (13.5-22vdc) into two paths.

[0089] Further, the gate of the first MOS tube Q1 is connected with the collector of the first triode Q4 through the ninth resistor R9,

[0090] The base of the first triode Q4 is connected with a signal output end of the main control circuit 170 through the fourteenth resistor R14, and the control signal output by the main control circuit 170 is input to the base of the first triode Q4 through the fourteenth resistor R14 as a positive bias signal.

[0091] The emitter of the first transistor Q4 is connected to the common terminal.

[0092] When the output control signal is high, the first transistor Q4 is controlled to be turned on, and the point of the gate of the first MOS tube Q1 is pulled low, so that it is turned on. The low-voltage direct-current signal (13.5-22vdc) is output to the input voltage detection circuit 120 and the LED driving circuit 130 through the first MOS tube Q1.

[0093] In some embodiments, as shown in Figure 2a The switch circuit 110 further includes a touch switch SW2 (or corresponding 112), wherein one end of the touch switch SW2 is connected to the cathode of the fourth diode D4, the anode of the fourth diode D4 is connected to the gate of the first MOS tube Q1,

[0094] The other end of the touch switch SW2 is connected to the cathode of the third diode D3, and the anode of the third diode D3 is connected to a signal output terminal of the main control circuit 170.

[0095] When the touch switch SW2 is pressed, the signal output terminal (corresponding to pin 5) of the main control circuit 170 is low, and the potential of the gate of the first MOS tube Q1 is pulled low, so that the first MOS tube Q1 is turned on.

[0096] In some embodiments, as shown in Figure 2b In order to ensure the reliability of the voltage signal, the thirteenth resistor R13, the seventeenth resistor R17 and the seventh capacitor C7 can be arranged in the input voltage detection circuit 120,

[0097] The thirteenth resistor R13 and the seventeenth resistor R17 are connected in series and then connected in parallel with the seventh capacitor C7,

[0098] One end of the thirteenth resistor R13 is used to obtain the voltage signal,

[0099] The connection end of the seventeenth resistor R17 and the seventh capacitor C7 is connected to the voltage feedback end of the main control circuit 170, and the voltage signal after voltage division is output to the main control circuit 170, and the level state of the control signal is changed according to the comparison result after comparison processing.

[0100] In some embodiments, as shown in Figure 2b In order to improve the reliability of the LED module 140 control, the driver U1, the second transistor Q5, the third transistor Q6 and the second MOS tube Q2 can be arranged in the LED driving circuit 130,

[0101] The driver U1 can adjust the light of the LED module 140 according to the input PWM pulse signal;

[0102] The second transistor Q5 and the third transistor Q6 are NPN transistors,

[0103] The second MOS transistor Q2 is an N-channel MOS transistor, and both have the function of switching.

[0104] Specifically, the power terminal (corresponding to pin 1) of the driver U1 is connected with the drain of the first MOS transistor Q1, for receiving a low-voltage direct-current signal (13.5-22VDC),

[0105] The base of the second transistor Q5 is connected with the drain of the first MOS transistor Q1 through the second resistor R23, and the input low-voltage direct-current signal (13.5-22VDC) is divided and used as a bias signal.

[0106] The collector of the second transistor Q5 is connected with the input terminal (corresponding to pin 3) of the driver U1,

[0107] The base of the third transistor Q6 is connected with another signal output terminal of the main control circuit 170 through the sixteenth resistor R16, for receiving the PWM pulse signal output by the main control circuit 170.

[0108] The collector of the third transistor Q6 is connected with the base of the second transistor Q5,

[0109] The gate of the second MOS transistor Q2 is connected with the output terminal (corresponding to pin 5) of the driver U1, for receiving the driving signal output by the driver U1,

[0110] The drain of the second MOS transistor Q2 is connected with the current sampling terminal (corresponding to pin 2) of the driver U1 and the positive terminal (corresponding to LED+1) of the LED module 140 through the first inductor L1,

[0111] The emitter of the second transistor Q5, the emitter of the third transistor Q6 and the source of the second MOS transistor Q2 are respectively connected with a common terminal.

[0112] When the PWM pulse signal output by the main control circuit 170 is high, the third transistor Q6 and the second transistor Q5 are controlled to be turned on, the PWM pulse signal is input to the driver U1, and the input PWM pulse signal is processed by the driver U1, so as to adjust the duty ratio of the driving signal for controlling the second MOS transistor Q2 to be turned on, and further adjust the brightness of the LED module 140.

[0113] In some embodiments, as shown in Figure 2e In order to improve the safety and reliability of the LED lighting product, a magnetic sensor U5, a tenth capacitor C10 and a thirteenth capacitor C13 can be arranged in the magnetic induction detection circuit 160.

[0114] The input terminal of the magnetic sensor U5 is used to obtain the magnetic induction signal formed by the shell magnet,

[0115] One end of the thirteenth capacitor C13 and the power supply end of the magnetic sensor U5 are connected to the VDD power supply end,

[0116] One end of the tenth capacitor C10 is connected to the output end of the magnetic sensor U5,

[0117] The output end of the magnetic sensor U5 is connected to a signal input end of the main control circuit 170 for receiving a magnetic induction signal,

[0118] The other end of the tenth capacitor C10 and the thirteenth capacitor C13 and the ground end of the magnetic sensor U5 are connected to the common end.

[0119] In some embodiments, as shown in Figure 2e The main control circuit 170 at least includes a main controller U4,

[0120] One signal input end (corresponding to pin 7) of the main controller U4 is connected to the output end of the magnetic sensor U5 for receiving a magnetic induction signal,

[0121] The voltage feedback end (corresponding to pin 3) of the main controller U4 is connected to one end of the seventh capacitor C7 for receiving a voltage signal,

[0122] One signal output end (corresponding to pin 2) of the main controller U4 is connected to the base of the first triode Q4, and the first triode Q4 is used for receiving a control signal,

[0123] The other signal output end (corresponding to pin 4) of the main controller U4 is connected to the base of the third triode Q6, and the third triode Q6 is used for receiving a pulse signal.

[0124] As shown in Figure 3 When the magnetic sensor U5 senses a magnetic induction signal, the level of pin 7 of the main controller U4 changes from high to low, and after 8 seconds, the main controller U4 outputs a 20% duty cycle signal to pin 4 through an internal timer PWM, and the LED module 140 changes from originally strong brightness (100% duty cycle) to dim brightness (about 20% duty cycle), at the same time, the power of the entire circuit is reduced, at this time, it can be judged that the LED module 140 is in an abnormal use state;

[0125] When the level of pin 7 of the main controller U4 changes from low to high, the duty cycle will be reset to strong brightness 100%;

[0126] When the input voltage is normally working at 13.5-22V, when the voltage of pin 3 of the main controller U4 is lower than 13.5VDC, a low level signal is output through pin 2 of the main controller U4, so that the first triode Q4 changes from conduction to cut-off, so that the entire circuit is in a closed state.

[0127] The working principle is as follows:

[0128] The input voltage is output to the S pole of the circuit switch control first MOS tube Q1 through the anti-connection rectification second diode D2. When the touch switch SW2 is pressed, the touch switch SW2, the eighth resistor R8, the fourth capacitor C4 and the third diode D3 form a switch circuit, the 5 pin level of the main controller U4 changes from high to low, and the touch switch SW2 is pressed, the touch switch SW2, the fourth diode D4, the ninth resistor R9, the third resistor R3 and the first voltage stabilizing diode ZD1 form a switch circuit, the gate of the first MOS tube Q1 is low, and the first MOS tube Q1 is turned on at this time,

[0129] The 2 pin level of the main controller U4 changes from low to high at this time, the first triode Q4 is turned on, the G pole of the first MOS tube Q1 is directly pulled low, and the first MOS tube Q1 is always in the on working state, thereby providing a stable working voltage for the subsequent circuit; when the first MOS tube Q1 is turned on, the voltage signal is subjected to voltage detection through the thirteenth resistor R13, the seventeenth resistor R17 and the seventh capacitor C7, and the detected voltage is input to the 3 pin of the main controller U4; the main controller U4 judges whether the current input voltage belongs to the set input voltage range value (such as 13.5-22V) through the internal ADC value.

[0130] If it is out of or lower than the range value, the 2 pin level of the main controller U4 changes from high to low, the first triode Q4 is in the cut-off state at this time, the first MOS tube Q1 changes from on to off, thereby closing the entire circuit; similarly, when the first MOS tube Q1 is turned on, the voltage signal is input to the main controller U4 through the sixth diode D6, the twentieth resistor R20, the capacitor E1, the ninth capacitor C9, the low-voltage difference linear voltage stabilizer U2, the eighth capacitor C8 and the eleventh capacitor C11, and the voltage is stepped down through the twentieth resistor R20 after passing through the sixth diode D6 to supply the low-voltage difference linear voltage stabilizer U2, thereby outputting a stable 3.3V voltage source for the main controller U4;

[0131] Similarly, when the input voltage is stepped down to 3.3V by the low-voltage difference linear voltage stabilizer U2 to supply the magnetic sensor U5, when the magnetic sensor U5 senses the magnet of the product shell, it indicates that the product is in an abnormal working state at this time, the magnetic sensor U5 directly pulls the 7 pin level signal of the main controller U4 from high to low, the main controller U4 adjusts the duty cycle from the original 100% to 20% through the internal PWM pulse signal 4 pin, and the 5 pin is connected to the adjustment light intensity DIM control pin of the driver U1 through the second triode Q5 and the third triode Q6; the turn-on voltage of the first MOS tube Q1 is used to supply the subsequent circuit, and the driver U1 has the dimming function.

[0132] When the magnetic sensor U5 detects that the LED module 140 is in abnormal operation, the duty cycle of the 4th pin of the main controller U4 is adjusted from the original 100% to 20%, which is connected to the 3rd pin (DIM dimming pin) of the driver U1 through the second triode Q5 and the third triode Q6, at this time, the LED current is reduced from the original 100% to the original 20%, the brightness is reduced from the original 100% to 20%, thereby reducing the heat dissipation of the LED module 140, solving the problem of safety hidden trouble caused by heat dissipation due to misoperation, and prolonging the endurance time of the LED module 140.

[0133] The embodiments of the utility model are described above in combination with the drawings, but the utility model is not limited to the specific implementation manners described above, and the specific implementation manners described above are only illustrative but not restrictive, and the ordinary skilled in the art can make many forms under the inspiration of the utility model without departing from the scope of the utility model and the protection scope of the claims, and these all belong to the protection of the utility model.

Claims

1. An LED module control circuit, characterized by, Possessing: A switch circuit is configured in the control circuit, the input end is used for receiving low-voltage direct current signal; Input voltage detection circuit, its input end is coupled to the output end of the switch circuit, is used for obtaining voltage signal; LED drive circuit, its input end is coupled to the output end of the switch circuit, is used for obtaining the direct current signal, and the direct current signal is used to trigger LED module; Magnetic induction detection circuit, its input end is used for obtaining the magnetic induction signal formed by the shell magnet; The main control circuit is used for outputting at least one control signal and pulse signal, wherein, The signal input end of the main control circuit is connected with the output end of the magnetic induction detection circuit, is used for receiving the magnetic induction signal, The voltage feedback end of the main control circuit is connected with the output end of the input voltage detection circuit, is used for receiving the voltage signal, The signal output end of the main control circuit is connected with the signal input end of the switch circuit, is used for receiving the control signal, The other signal output end of the main control circuit is connected with the signal input end of the LED drive circuit, is used for receiving the pulse signal, When the magnetic induction detection circuit does not induct the magnetic induction signal, the output control signal is high level, and the switch circuit is controlled to be turned on to control the LED module to work; When the magnetic induction detection circuit inducts the magnetic induction signal, the main control circuit reduces the duty cycle of the pulse signal to reduce the brightness of the LED module; When the feedback voltage signal is lower than the preset value, the output control signal is low level, and the switch circuit is controlled to be turned off.

2. The LED module control circuit according to claim 1, wherein, The switch circuit at least includes a first MOS tube and a first triode, The source of the first MOS tube is connected with the output side of the power supply through a second diode, is used for receiving low-voltage direct current signal, The drain of the first MOS tube is connected with the input end of the input voltage detection circuit and the LED drive circuit respectively, The gate of the first MOS tube is connected with the collector of the first triode through the ninth resistor, The base of the first triode is connected with the signal output end of the main control circuit through the fourteenth resistor, The emitter of the first triode is connected with the common end.

3. The LED module control circuit according to claim 2, wherein, The switch circuit further includes a touch switch, One end of the touch switch is connected with the gate of the first MOS tube through a fourth diode, The other end of the touch switch is connected with the signal output end of the main control circuit through a third diode.

4. The LED module control circuit according to claim 2, wherein, The input voltage detection circuit includes a thirteenth resistor, a seventeenth resistor and a seventh capacitor, The thirteenth resistor and the seventeenth resistor are connected in series and then connected in parallel with the seventh capacitor, One end of the thirteenth resistor is used for obtaining the voltage signal, The connection end of the seventeenth resistor and the seventh capacitor is connected with the voltage feedback end of the main control circuit.

5. The LED module control circuit according to claim 4, wherein, The LED driving circuit at least comprises a driver, a second triode, a third triode and a second MOS tube, a power supply end of the driver is connected with a drain of the first MOS tube, a base of the second triode is connected with the drain of the first MOS tube through a second twenty-third resistance, a collector of the second triode is connected with an input end of the driver, a base of the third triode is connected with another signal output end of the main control circuit through a sixteenth resistance, a collector of the third triode is coupled with a base of the second triode, a gate of the second MOS tube is connected with an output end of the driver, a drain of the second MOS tube is connected with a current sampling end of the driver and a positive pole of the LED module through a first inductor, an emitter of the second triode, an emitter of the third triode and a source of the second MOS tube are respectively connected with a common end.

6. The LED module control circuit according to claim 5, wherein, the magnetic induction detection circuit at least comprises a magnetic sensor, an input end of the magnetic sensor is used to acquire the magnetic induction signal formed by the shell magnet, an output end of the magnetic sensor is connected with a signal input end of the main control circuit, and is used to receive the magnetic induction signal.

7. The LED module control circuit according to claim 6, wherein, the main control circuit at least comprises a main controller, a signal input end of the main controller is connected with an output end of the magnetic sensor, and is used to receive the magnetic induction signal, a voltage feedback end of the main controller is connected with one end of the seventh capacitor, and is used to receive the voltage signal, a signal output end of the main controller is connected with a base of the first triode, and the first triode is used to receive the control signal, another signal output end of the main controller is connected with a base of the third triode, and the third triode is used to receive the pulse signal.

8. The LED module control circuit according to claim 7, wherein, the first triode, the second triode and the third triode are selected as NPN type triodes, the first MOS tube is selected as a P channel MOS tube, the second MOS tube is selected as an N channel MOS tube.

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