LED lamp afterglow removal control circuit

Abstract

The invention discloses an LED lamp afterglow removal control circuit, and belongs to the technical field of electrical engineering. The problem that after a non-isolated power supply is subjected to 0-10 V dimming and light-off, the LED lamp bead has afterglow slight light is solved. According to the technical scheme, a detection control circuit composed of a voltage stabilizing diode, a resistor and an MOS tube is additionally arranged at the output end of a conventional buck-boost topology; whether output voltage exceeds a set threshold value or not is judged through a voltage stabilizing detection module, and then on-off of a PMOS tube is controlled; and when the voltage is lower than a threshold value, the LED power supply loop is completely cut off, and a leakage current path formed by coupling of the lamp panel is eliminated. According to the invention, the afterglow phenomenon after the lamp is turned off is thoroughly eliminated, the circuit structure is simple, the reliability is high, and the circuit is suitable for various non-isolated dimming LED lamps.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of electrical engineering, and particularly relates to a LED lamp de-afterglow control circuit. BACKGROUND

[0002] At present, the common LED lighting lamps on the market generally adopt a power supply circuit of buck-boost non-isolated topology structure, and the output is directly supplied to the LED lamp bead load. In actual application, it is found that when the lamps cooperate with the 0-10V dimming system for dimming and are dimmed to the off state, the LED lamp bead still appears a weak light emission phenomenon, which is usually called "afterglow" or "ghost fire". The phenomenon is caused by the fact that there is still a voltage with a certain amplitude at the output end of the power supply, which is coupled to the shell ground line through the LED lamp bead and the lamp panel, forming a complete leakage current loop. Although the voltage value is much lower than the working voltage required for normal lighting of the LED lamp bead, it is still higher than the turn-on threshold voltage, resulting in that the LED still emits weak light in the off state. This afterglow phenomenon not only seriously affects the visual experience of the user and the use effect of the lighting product, but also may affect the service life of the LED due to the long-term micro-current passing, and even cause safety hazards. In the prior art, there is a lack of an effective solution with simple structure and low cost. Usually, the afterglow needs to be suppressed by means of a complex auxiliary circuit or a special control chip, which not only increases the system complexity and design difficulty, but also significantly increases the product cost, and it is difficult to be widely applied in popular LED lighting products. Therefore, how to fundamentally eliminate the afterglow phenomenon of the non-isolated dimming power supply after being turned off without significantly increasing the cost has become a technical problem to be solved in the field. SUMMARY

[0003] To solve the above technical problems, the present application provides a LED lamp de-afterglow control circuit to solve the problems existing in the prior art.

[0004] In the first aspect, to achieve the above object, the present application provides a LED lamp de-afterglow control circuit, comprising the following steps:

[0005] A signal voltage detection module, the input end of which is connected to the rectified output end of the non-isolated topology power supply, and is used to output a conduction signal when the voltage at the rectified output end is higher than a set threshold value;

[0006] A control output module, the control end of which is connected to the output end of the signal voltage detection module, the input end of which is connected to the rectified output end, and the output end of which is connected to the positive electrode of the LED lamp bead;

[0007] When the signal voltage detection module outputs the conduction signal, the control output module is turned on to supply the rectified output end to the LED lamp bead;

[0008] When the signal voltage detection module does not have the conductive signal output, the control output module is turned off to cut off the power supply loop to the LED lamp bead.

[0009] Optionally, the signal voltage detection module comprises a first voltage stabilizing unit, a voltage dividing unit and a switching unit.

[0010] The input end of the first voltage stabilizing unit is connected to the rectification output end.

[0011] The output end of the first voltage stabilizing unit is connected to the control end of the switching unit through the voltage dividing unit.

[0012] The output end of the switching unit serves as the output end of the signal voltage detection module.

[0013] Optionally, the first voltage stabilizing unit comprises at least two series-connected voltage stabilizing diodes.

[0014] Optionally, the voltage dividing unit comprises a first resistor and a second resistor.

[0015] One end of the first resistor is connected to the output end of the first voltage stabilizing unit.

[0016] The other end of the first resistor is connected to one end of the second resistor and the control end of the switching unit.

[0017] The other end of the second resistor is grounded.

[0018] Optionally, the switching unit comprises an N-channel field effect transistor.

[0019] The gate of the N-channel field effect transistor is connected to the voltage dividing unit, the source is grounded, and the drain serves as the output end of the switching unit.

[0020] Optionally, the control output module comprises a P-channel field effect transistor.

[0021] The source of the P-channel field effect transistor is connected to the rectification output end, the drain is connected to the positive electrode of the LED lamp bead, and the gate is connected to the output end of the signal voltage detection module.

[0022] In a second aspect, the present application further provides an LED lamp de-blooming control method, which is used for realizing the LED lamp de-blooming control circuit and comprises the following steps.

[0023] Detecting the voltage of the rectification output end of the non-isolation topology power supply.

[0024] When the rectification output end voltage is higher than a set threshold, generating a conductive control signal.

[0025] According to the on-off control signal, a power supply loop connected between the rectification output end and a positive electrode of the LED lamp bead is controlled to be turned on.

[0026] When the rectification output end voltage is lower than a set threshold value, the generation of the on-off control signal is stopped.

[0027] According to absence of the on-off control signal, the power supply loop is controlled to be turned off.

[0028] In a third aspect, the present application further provides a computer terminal device, comprising:

[0029] One or more processors;

[0030] A memory coupled to the processor, configured to store one or more programs;

[0031] When the one or more programs are executed by the one or more processors, the one or more processors implement the steps of the LED lamp de-blooming control method in the second aspect.

[0032] In a fourth aspect, the present application further provides a computer readable storage medium, having a computer program stored thereon, wherein the computer program is executed by a processor to implement the steps of the LED lamp de-blooming control method in the second aspect.

[0033] In a fifth aspect, the present application further provides a computer program product, comprising a computer program, wherein the computer program is executed by a processor to implement the steps of the LED lamp de-blooming control method in the second aspect.

[0034] Compared with the prior art, the present application has the following advantages and technical effects:

[0035] The LED lamp de-blooming control circuit provided by the present application completely eliminates the LED afterglow phenomenon after the non-isolated power supply dimming and lamp-off, automatically controls the on-off of the power supply loop by detecting the output voltage, and solves the problem of the slight light of the lamp bead due to the coupling loop. The scheme adds a voltage stabilizing detection and MOS tube control structure in the conventional circuit, turns on the power supply only when the output voltage is sufficient, completely cuts off the loop when the voltage is insufficient, and ensures that no current passes through the LED lamp bead. The structure is simple, the cost is low, the compatibility is strong, and the scheme can be widely applied to various non-isolated topology LED dimming systems, and does not need a complex control algorithm, has high reliability, and is suitable for large-scale commercial application. BRIEF DESCRIPTION OF DRAWINGS

[0036] The accompanying drawings, which form a part of this application, are intended to provide further understanding of the application and are incorporated herein for a purpose of explanations. The illustrative embodiments of the present application, together with its description, are used to explain the present application and do not constitute an inappropriate limitation of the present application. In the drawings:

[0037] Figure 1 Circuit diagram for an embodiment of the application;

[0038] Figure 2 Waveform diagram of the output voltage without residual for an embodiment of the application;

[0039] Figure 3 Waveform diagram of the output voltage with residual for an embodiment of the application;

[0040] Figure 4 Waveform diagram of the G-pole voltage when Q3 is on for an embodiment of the application;

[0041] Figure 5 Waveform diagram of the G-pole voltage when Q3 is off for an embodiment of the application;

[0042] Figure 6 Waveform diagram of the G-pole voltage when Q1 is on for an embodiment of the application;

[0043] Figure 7 Waveform diagram of the G-pole voltage when Q1 is off for an embodiment of the application;

[0044] Figure 8 Waveform diagram of the D-pole voltage when Q1 is on for an embodiment of the application;

[0045] Figure 9 Waveform diagram of the D-pole voltage when Q1 is off for an embodiment of the application. DETAILED DESCRIPTION

[0046] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0047] It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described herein can be executed in an order different from that shown herein.

[0048] Embodiment one

[0049] An LED lamp de-residual control circuit is provided in the embodiment, comprising:

[0050] A signal voltage detection module, an input end of which is connected to a rectified output end of a non-isolated topology power supply, for outputting a conduction signal when the voltage at the rectified output end is higher than a set threshold value;

[0051] A control output module, a control end of which is connected to an output end of the signal voltage detection module, an input end of which is connected to the rectified output end, and an output end of which is connected to a positive electrode of an LED lamp bead;

[0052] When the signal voltage detection module outputs the conduction signal, the control output module is turned on to supply power to the LED lamp bead through the rectification output end;

[0053] When the signal voltage detection module does not output the conduction signal, the control output module is turned off to cut off the power supply circuit to the LED lamp bead.

[0054] As an embodiment in the present embodiment, the signal voltage detection module comprises a first voltage stabilizing unit, a voltage dividing unit and a switching unit;

[0055] The input end of the first voltage stabilizing unit is connected to the rectification output end;

[0056] The output end of the first voltage stabilizing unit is connected to the control end of the switching unit through the voltage dividing unit;

[0057] The output end of the switching unit is the output end of the signal voltage detection module.

[0058] As an embodiment in the present embodiment, the first voltage stabilizing unit comprises at least two series-connected voltage stabilizing diodes.

[0059] As an embodiment in the present embodiment, the voltage dividing unit comprises a first resistor and a second resistor;

[0060] One end of the first resistor is connected to the output end of the first voltage stabilizing unit;

[0061] The other end of the first resistor is connected to one end of the second resistor and the control end of the switching unit;

[0062] The other end of the second resistor is grounded.

[0063] As an embodiment in the present embodiment, the switching unit comprises an N-channel field effect transistor;

[0064] The gate of the N-channel field effect transistor is connected to the voltage dividing unit, the source is grounded, and the drain is the output end of the switching unit.

[0065] As an embodiment in the present embodiment, the control output module comprises a P-channel field effect transistor;

[0066] The source of the P-channel field effect transistor is connected to the rectification output end, the drain is connected to the positive electrode of the LED lamp bead, and the gate is connected to the output end of the signal voltage detection module.

[0067] The LED lighting lamp of the present application is a kind of automatic control circuit for removing non-isolated power supply 0-10V dimming light-off LED lamp micro-bright jitter. The schematic diagram of the present application is as followsFigure 1 consisting of ZD7, ZD8, R98, ZD6, R101, Q3, R102, ZD3, R95, Q1.

[0068] As the scheme of the present application: the signal voltage detection module includes ZD7, ZD8, R98, ZD6, R101, Nmos Q3, the negative electrode of ZD7 is connected to the rectified output end of the buck-boost topology circuit, the positive electrode of ZD7 is connected to the negative electrode of ZD8, the positive electrode of ZD8 is connected to one end of R98, one end of R98 is connected to the negative electrode of ZD6, the negative electrode of ZD6 is connected to one end of R101, one end of R101 is connected to the G electrode of Nmos Q3, the S electrode of Nmos is grounded, one end of R101 is grounded, and one end of the positive electrode of ZD6 is connected to the ground. The control output circuit includes R102, ZD3, R95, Pmos Q1, one end of R102 is connected to the voltage detection module, the other end of R102 is connected to the G electrode of Pmos, the positive electrode of ZD3 is connected, one end of R95 is connected, the S electrode of Pmos Q1 is connected to the rectified output end of the buck-boost topology circuit, and the D electrode of Pmos Q1 is connected to the positive electrode of the LED lamp bead. The present application additionally increases ZD and R, Nmos (signal voltage detection module), Pmos (control output circuit) in the common circuit.

[0069] After the mains power is protected by the fuse F1 (short circuit protection) and the voltage sensitive resistor MOV1 (overvoltage protection) and is rectified into a direct current voltage by the BD1 bridge rectifier bridge, it enters the buck-boost topology to directly power the level voltage detection circuit. When the voltage is greater than 60V, ZD7 and ZD8 (two 30V Zener diodes in series) are broken down, R98 and R101 are divided, and when the divided voltage is greater than 1.2V, there is a high voltage on the G electrode of Q3, Q3 is turned on, the G electrode voltage of PMOS Q1 is pulled down when Q1 is turned on, and the LED lamp bead is powered. When the voltage is lower than 60V, ZD7 and ZD8 are not broken down, the voltage of the R98 and R101 voltage dividing circuit is zero, the G electrode voltage of Q1 is low, Q1 is cut off, the G electrode voltage of Q3 is not pulled down, Q3 is cut off, the output power supply circuit is cut off, the power supply circuit is directly supplied to the LED load through the buck-boost, the LED lamp bead forms a loop through the lamp panel coupling and the shell ground wire connection, the LED lamp bead loop is cut off, there is very low voltage to the lamp bead through the lamp panel coupling to the shell ground wire to form a self-coupling loop, which is cut off, the voltage is 27V, which is much smaller than the VF value of the lamp bead of 100V-158V, and the lamp bead will not be lit, and there will be no afterglow or ghost fire. As shown in the voltage waveform diagram without afterglow light. Figure 2

[0070] ​One aspect of the present application is to add Nmos and Pmos and peripheral devices to the common circuit.

[0071] Another aspect is to eliminate the ghost fire of LED lamp beads after the non-isolated power supply 0-10V dimming and light extinguishing.

[0072] When the buck-boost topology circuit has a voltage output greater than 60V, ZD7 and ZD8 are in series to stabilize and break down, and R98 and R101 are divided to provide power to Q3 G. When the voltage of Q3 G is greater than 1.2V, Q3 D-S is turned on, which pulls down the G level of Q1, and when the G level of Q1 changes, Q1 D-S is turned on to supply power to the LED lamp beads. When the output of the buck-boost topology circuit is less than 60V, the opposite is true. The specific waveform is shown in Figures 4-9 .

[0073] In the present application, the list of elements involved includes:

[0074] ZD7, ZD8 stabilizing diode MM1Z30 30V SOD-123;

[0075] ZD6 stabilizing diode BZT52B5V1 5.1V SOD123;

[0076] ZD3 stabilizing diode BZT52C8V2 SOD-123;

[0077] Q3 MOS UT3N10G 100V 3A SOT23;

[0078] Q1 PMOS AP3P10MSI 100V 3A SOT-223;

[0079] R98 100K 1206;

[0080] R102 150K 1206;

[0081] R95 51K 1206;

[0082] R101 10K 0805;

[0083] C15 10nF / 1000V 1206.

[0084] In the present application, it is necessary to pay attention that ZD7 and ZD7 should not be too high, otherwise the voltage will not break down, and the voltage on the R98 and R101 voltage dividing circuit will not be divided, and the output circuit part will not have an output;

[0085] Q1 and Q3 G need a stabilizing tube to prevent permanent damage due to high voltage G breakdown.

[0086] Based on this, the LED lamp de-persistence control circuit provided by the embodiment of the application completely eliminates the afterglow phenomenon of the LED lamp beads after the 0-10V dimming of the non-isolated power supply, automatically controls the on-off of the power supply loop through detection of the output voltage, and solves the problem of the slight light caused by the leakage loop formed by the lamp panel coupling. The scheme adds a voltage stabilization detection and MOS tube control structure in the conventional circuit, turns on the power supply only when the output voltage is sufficient, completely cuts off the loop when the voltage is insufficient, ensures that no current passes through the LED lamp beads, and thus fundamentally eliminates the ghost fire. The circuit structure is simple, the cost is low, the compatibility is strong, the scheme can be widely applied to various non-isolated topology LED dimming systems, does not require a complex control algorithm, has high reliability, and is suitable for large-scale commercial application.

[0087] Embodiment two

[0088] Based on the same overall inventive concept, the application also provides an LED lamp de-persistence control method. The LED lamp de-persistence control method provided by the application is described below, and the LED lamp de-persistence control method described below can be mutually correspondingly referred to the LED lamp de-persistence control circuit described above. The method comprises the following steps:

[0089] Detecting the voltage of the rectification output end of the non-isolated topology power supply;

[0090] When the rectification output end voltage is higher than a set threshold, a turn-on control signal is generated;

[0091] According to the turn-on control signal, the on-off of the power supply loop connected between the rectification output end and the anode of the LED lamp bead is controlled;

[0092] When the rectification output end voltage is lower than the set threshold, the generation of the turn-on control signal is stopped;

[0093] According to the absence of the turn-on control signal, the power supply loop is controlled to be turned off.

[0094] As an implementation manner in the embodiment, the step of generating the turn-on control signal comprises the following steps:

[0095] The rectification output end voltage is subjected to voltage stabilization processing;

[0096] The voltage after the voltage stabilization processing is subjected to voltage division processing;

[0097] The on-off of the switch unit is controlled according to the voltage after the voltage division processing to generate the turn-on control signal.

[0098] As an implementation manner in the embodiment, the voltage stabilization processing comprises voltage stabilization of the rectification output end voltage by at least two series-connected voltage stabilization diodes.

[0099] As an implementation form in the embodiment, the voltage dividing processing comprises voltage dividing the voltage after the voltage stabilizing processing by a voltage dividing circuit composed of the first resistor and the second resistor.

[0100] As an implementation form in the embodiment, the controlling the on-off of the switch unit comprises realizing the on-off control by an N-channel field effect transistor, a gate of the N-channel field effect transistor receiving the voltage after the voltage dividing processing, a source being grounded, and a drain outputting the on control signal.

[0101] As an implementation form in the embodiment, the controlling the on-off of the power supply circuit comprises realizing the on-off control of the circuit by a P-channel field effect transistor, a source of the P-channel field effect transistor being connected to the rectifier output end, a drain being connected to the positive electrode of the LED lamp bead, and a gate receiving the on control signal.

[0102] It should be understood that the LED lamp de-blooming control method provided by the embodiment has all the advantages of the LED lamp de-blooming control circuit provided by the above-mentioned embodiment.

[0103] In the embodiment, a computer terminal device is provided, comprising:

[0104] one or more processors;

[0105] a memory, coupled to the processor, for storing one or more programs;

[0106] When the one or more programs are executed by the one or more processors, the one or more processors implement the steps of the LED lamp de-blooming control method.

[0107] In the embodiment, a computer readable storage medium is also provided, which stores a computer program, and the computer program is executed by a processor to implement the steps of the LED lamp de-blooming control method.

[0108] In the embodiment, an electronic device is also provided, which comprises a memory and a processor, the memory stores a computer program, and the processor is configured to run the computer program to execute the steps of the LED lamp de-blooming control method.

[0109] In the embodiment, a computer program product is also provided, which comprises a computer program, and the computer program is executed by a processor to implement the steps of the LED lamp de-blooming control method.

[0110] The above-described processes can be implemented on a processor, or can be stored on a storage medium (or computer-readable medium), which includes permanent and non-permanent, removable and non-removable media, and can be implemented by any method or technology to store information. Information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassette, magnetic tape disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information accessible by a computing device.

[0111] These computer programs can also be loaded into a computer or other programmable data processing device, so that a series of operation steps are performed on the computer or other programmable device to generate a computer-implemented process, so that the instructions executed on the computer or other programmable device provide a process for implementing the functions specified in the flowchart Figure 1 The functions specified in one flowchart or multiple flowcharts and / or blocks Figure 1 The functions specified in one flowchart or multiple flowcharts and / or blocks

[0112] The system or device is used to realize the functions of the method in the above-mentioned embodiments, each module in the system or device corresponds to each step in the method, which has been described in the method and will not be repeated here.

[0113] The above is only the preferred specific embodiment of the present application, but the protection scope of the present application is not limited to this, any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A circuit for controlling afterglow reduction in LED lighting fixtures, characterized in that, Includes the following steps: The signal voltage detection module has its input terminal connected to the rectifier output terminal of a non-isolated topology power supply, and is used to output a conduction signal when the voltage at the rectifier output terminal is higher than a set threshold. The control output module has its control terminal connected to the output terminal of the signal voltage detection module, its input terminal connected to the rectifier output terminal, and its output terminal connected to the positive electrode of the LED bead. When the signal voltage detection module outputs the conduction signal, the control output module is turned on to supply the LED beads with the power of the rectified output terminal; When the signal voltage detection module does not output the conduction signal, the control output module is turned off to cut off the power supply circuit to the LED beads.

2. The circuit according to claim 1, characterized in that, The signal voltage detection module includes: a first voltage regulator unit, a voltage divider unit, and a switching unit; The input terminal of the first voltage regulator unit is connected to the rectifier output terminal; The output of the first voltage regulator unit is connected to the control terminal of the switching unit via the voltage divider unit; The output terminal of the switching unit serves as the output terminal of the signal voltage detection module.

3. The circuit according to claim 2, characterized in that, The first voltage regulator unit includes at least two Zener diodes connected in series.

4. The circuit according to claim 2, characterized in that, The voltage divider unit includes a first resistor and a second resistor; One end of the first resistor is connected to the output terminal of the first voltage regulator unit; The other end of the first resistor is connected to one end of the second resistor and is also connected to the control terminal of the switching unit. The other end of the second resistor is grounded.

5. The circuit according to claim 2, characterized in that, The switching unit includes an N-channel field-effect transistor; The gate of the N-channel field-effect transistor is connected to the voltage divider unit, the source is grounded, and the drain serves as the output terminal of the switching unit.

6. The circuit according to claim 1, characterized in that, The control output module includes a P-channel field-effect transistor; The source of the P-channel field-effect transistor is connected to the rectifier output terminal, the drain is connected to the positive terminal of the LED bead, and the gate is connected to the output terminal of the signal voltage detection module.

7. A method for controlling afterglow in LED lighting fixtures, characterized in that, The method includes: Detect the voltage at the rectified output terminal of a non-isolated power supply; When the voltage at the rectified output terminal is higher than a set threshold, a conduction control signal is generated; According to the conduction control signal, the power supply circuit connected between the rectifier output terminal and the positive terminal of the LED bead is controlled to be turned on; When the voltage at the rectified output terminal is lower than a set threshold, the generation of the conduction control signal is stopped. The power supply circuit is shut off when the conduction control signal is missing.

8. A computer terminal device, characterized in that, include: One or more processors; A memory, coupled to the processor, for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors perform the steps of the method as described in claim 7.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as described in claim 7.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the method of claim 7.

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