A method to prevent non-isolated LED driver from starting flashing

Abstract

The present invention relates to the technical field of LED lamps, and provides a method for preventing a non-isolated LED driver from starting a flashing light, comprising: configuring a target control circuit, the target control circuit being used to implement basic control of the non-isolated LED driver starting a flashing light; updating the configuration of the functional modules in the target control circuit and improving the connection structure to obtain a first target control circuit; and based on the first target control circuit, controlling the non-isolated LED driver from starting a flashing light. The present invention adopts a synchronous control method to ensure that the LED lamp avoids the occurrence of micro-flickering when the LED lamp is in the driving-on state, thereby improving the user experience of the LED lamp.

Description

Technical Field

[0001] The present invention relates to the technical field of LED lamps, and in particular to a method for preventing a non-isolated LED from being driven and starting to flash. Background Art

[0002] For non-isolated LED driver power supply, due to the parasitic capacitance between the lamp beads and the lamp, when the lamp is grounded and the non-isolated LED driver is started, the AC power rushes and discharges to the parasitic capacitance through the lamp beads, causing the lamp to appear slightly bright for a period of time after starting up, and a slight flickering phenomenon appears to the senses.

[0003] The traditional solution to prevent the non-isolated LED driver from starting the flashing light includes: a non-isolated power factor correction module, an afterglow control module, a load constant current control module, an LED load lamp, and a parasitic capacitor between the lamp and the earth PE; the non-isolated power factor correction module mainly converts the AC mains into a stable DC voltage and ensures a high power factor of the driving power supply; the afterglow control module ensures that the LED load has no afterglow when the driving power supply is in standby mode; the load conversion control module converts the output voltage of the power factor correction module into the current or voltage required by the LED load. The traditional solution can ensure that the LED load has no afterglow in the standby mode; but when the driver is turned on, due to the lack of synchronous control, micro-flickering will occur.

[0004] Therefore, it is necessary to provide a method to prevent a non-isolated LED driver from starting to flash. Summary of the invention

[0005] The present invention provides a method for preventing a non-isolated LED lamp from flashing when it is driven and starts, and adopts a synchronous control method to ensure that the LED lamp avoids the occurrence of micro-flickering when it is driven and starts, thereby improving the user experience of the LED lamp.

[0006] The present invention provides a method for preventing a non-isolated LED driver from starting a flashing light, comprising:

[0007] Configure the target control circuit, which is used to realize the basic control of the non-isolated LED driver to start the flashing light;

[0008] Updating the configuration and improving the connection structure of the functional modules in the target control circuit to obtain a first target control circuit;

[0009] Based on the first target control circuit, control is performed to prevent the non-isolated LED driver from starting to flash.

[0010] Further, the target control circuit is configured, including:

[0011] Configure the functional modules, LED load, parasitic capacitance and AC power supply of the target control circuit;

[0012] Connect the functional modules, LED load, parasitic capacitance and AC power supply to generate the target control circuit.

[0013] Furthermore, the functional modules of the target control circuit are configured, including:

[0014] Configure a power factor correction module, which is used to convert the AC power supply into a DC voltage and ensure a high power factor of the LED drive power supply;

[0015] Configure the afterglow control module, which is used to ensure that the LED load has no afterglow when the LED driver power supply is in standby mode;

[0016] A load conversion control module is configured, and the load conversion control module is used to convert the DC voltage output by the power factor correction module into the current or voltage required by the LED load.

[0017] Further, the functional module, LED load, parasitic capacitor and AC power supply are connected to generate a target control circuit, including:

[0018] Connect the AC power supply to the power factor correction module, connect the power factor correction module to the afterglow control module, connect the afterglow control module to the load conversion control module, connect the load conversion control module to the LED load, connect the LED load to the parasitic capacitor, connect the parasitic capacitor to the ground wire, and generate a target control circuit.

[0019] Furthermore, the function module of configuring the target control circuit also includes:

[0020] The control chip U2, the power tube Q1, the inductor L1, the diode D1, the capacitor C1, the capacitor C2, the resistor R8, the resistor R9, the resistor R10 and the rectifier bridge BD1 are configured as a power factor correction module;

[0021] Configure relay K1 as afterglow control module;

[0022] The control chip U1, the resistor R1, the resistor R2, the resistor R3, the resistor R6, the resistor R7, the power tube Q3, the inductor L2, the diode D2, the diode D3, the transformer LF1 and the capacitor C3 are configured as a load conversion control module.

[0023] Furthermore, the functional modules in the target control circuit are updated in configuration and their connection structures are improved to obtain a first target control circuit, including:

[0024] A synchronous control module is configured between the afterglow control module and the load conversion control module. The synchronous control module includes a power tube Q2, a resistor R4, a resistor R5, a capacitor C4 and a diode D4.

[0025] Furthermore, the configuration of the functional modules in the target control circuit is updated and the connection structure is improved to obtain a first target control circuit, which further includes:

[0026] The afterglow control module is connected to the synchronous control module, and the synchronous control module is connected to the load conversion control module, specifically:

[0027] One input end of the rectifier bridge stack BD1 is connected to AC_L of the AC power supply, the other input end of the rectifier bridge stack BD1 is connected to AC_N of the AC power supply, one output end of the rectifier bridge stack BD1 is connected to one end of the inductor L1 and one end of the capacitor C1, and the other output end of the rectifier bridge stack BD1 is connected to the other end of the resistor R9 and the other end of the capacitor C1; the other end of the inductor L1 is connected to the anode of the diode D1; the cathode of the diode D1 is connected to one end of the capacitor C2, and the other end of the capacitor C2 is connected to the other end of the resistor R9; the other end of the resistor R9 is grounded; one end of the resistor R9 is connected to the other end of the resistor R10; one end of the resistor R10 is connected to the CS end of the control chip U2, the GND end of the control chip U2 is grounded, and the BATE end of the control chip U2 is connected to one end of the resistor R8; the other end of the resistor R8 is connected to the gate of the power tube Q1, the source of the power tube Q1 is connected to the other end of the resistor R10, and the drain of the power tube Q1 is connected to the anode of the diode D1;

[0028] The cathode of diode D1 is connected to pins 1 and 2 of relay K1;

[0029] Pin 4 of relay K1 is connected to one end of inductor L2 and the cathode of diode D3; the other end of inductor L2 is respectively connected to one end of capacitor C3, one end of resistor R1 and the input end of transformer LF1; the anode of diode D3 is respectively connected to the other end of capacitor C3, the other end of resistor R1 and the output end of transformer LF1; the output end of transformer LF1 is connected to LED load;

[0030] Pin 3 of relay K1 is connected to the collector of power tube Q2, the base of power tube Q2 is connected to one end of resistor R4, the other end of resistor R4 is respectively connected to one end of resistor R5 and the other end of capacitor C4, one end of capacitor C4 is grounded; the other end of resistor R5 is connected to the cathode of diode D4, the anode of diode D4 is connected to the third pulse width modulation signal input end; one end of resistor R4 is connected to the VREALAY signal input end;

[0031] The anode of the diode D3 is connected to the drain of the power tube Q3, and the gate of the power tube Q3 is connected to the anode of the diode D2 and one end of the resistor R2 respectively; the source of the power tube Q3 is connected to one end of the resistor R6 and one end of the resistor R7; the other end of the resistor R6 is grounded, and the other end of the resistor R7 is connected to the CS end of the control chip U1;

[0032] The cathode of the diode D2 is connected to one end of the resistor R3, and the other end of the resistor R3 and the other end of the resistor R2 are connected to the first pulse width modulation signal input end; the first pulse width modulation signal input end is connected to the GA end of the control chip U1, the first pulse width modulation signal is connected to the third pulse width modulation signal, the second pulse width modulation signal input end is connected to the PWM end of the control chip U1, and the GND end of the control chip U1 is grounded.

[0033] Furthermore, the second pulse width modulation signal is generated by a preset external dimming control module.

[0034] Further, based on the first target control circuit, control is performed to prevent the non-isolated LED driver from starting the flashing light, including:

[0035] Connect to AC power;

[0036] After the AC power is rectified by the rectifier bridge BD1, the power factor correction module is driven to start and output a DC voltage;

[0037] Outputting the second pulse width modulation signal generated by the external dimming control module to the control chip U1;

[0038] After the delay of the control chip U1, the first pulse width modulation signal acting on the power tube Q3 is at a low level. At this time, the afterglow control module and the load conversion control module are not started, and no parasitic current flows through the LED load;

[0039] Through the synchronous control module, a third pulse width modulation signal connected to the first pulse width modulation signal is used to control the relay K1 in the afterglow control module to be turned on, so that the power tube Q3 and the relay K1 in the afterglow control module are turned on at the same time, so as to visually avoid the LED lamp from flickering when it starts.

[0040] Further, based on the first target control circuit, the control of preventing the non-isolated LED driver from starting the flashing light is performed, and also includes setting a capacitor test circuit to test the capacitance of the capacitor C3, and setting an analog drive control circuit to simulate and determine the driving time of the LED load using the analog drive control circuit to determine the target capacitance of the capacitor C3, and update the configuration of the load conversion control module; specifically:

[0041] A controller, a capacitance test circuit and an analog drive control circuit are provided, wherein the capacitance test circuit and the analog drive control circuit are both connected to the controller; and the capacitance test circuit is connected to a load conversion control module;

[0042] Using the controller, based on the capacitance test circuit, the capacitance of the capacitor C3 in the load conversion control module is tested to obtain a capacitance test result;

[0043] Using the controller, based on the analog drive control circuit and according to the capacitance test result, a simulated drive test of the drive time of the LED load is performed to obtain a drive time simulation test result;

[0044] According to the driving time simulation test results and the driving time requirement of the LED load, the target driving time in the driving time simulation test results is determined, and the corresponding target capacitance value of the capacitor C3 is determined;

[0045] According to the target capacitance of capacitor C3, the configuration of the load conversion control module is updated.

[0046] Compared with the prior art, the present invention has the following advantages and beneficial effects: a synchronous control method is adopted to ensure that the LED lamp is driven and turned on without the occurrence of micro-flickering, thereby improving the user experience of the LED lamp.

[0047] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description and the accompanying drawings.

[0048] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0050] Figure 1 A schematic diagram of steps of a method for preventing a non-isolated LED driver from starting to flash;

[0051] Figure 2 is a schematic diagram of the module structure of a first target control circuit of an embodiment;

[0052] Figure 3 is a schematic diagram of a module structure of a first target control circuit of another embodiment;

[0053] Figure 4 A schematic diagram of the structural connection of a first target control circuit according to an embodiment;

[0054] Figure 5 A schematic diagram of the structural connection of a first target control circuit according to another embodiment;

[0055] Figure 6 A schematic diagram of the LED load current waveform under the control of the module based on the target control circuit;

[0056] Figure 7 It is a schematic diagram of the LED load current waveform under the control of the module based on the first target control circuit. DETAILED DESCRIPTION

[0057] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0058] The present invention provides a method for preventing a non-isolated LED driver from starting to flash. Figure 1 As shown, including:

[0059] Configure the target control circuit, which is used to realize the basic control of the non-isolated LED driver to start the flashing light;

[0060] Updating the configuration and improving the connection structure of the functional modules in the target control circuit to obtain a first target control circuit;

[0061] Based on the first target control circuit, control is performed to prevent the non-isolated LED driver from starting to flash.

[0062] The working principle of the above technical solution is: in order to implement a method for preventing a non-isolated LED driver from starting a flashing light, the present invention first configures a target control circuit, and the target control circuit is used to implement basic control of the non-isolated LED driver starting a flashing light; then the functional modules in the target control circuit are updated and the connection structure is improved to obtain a first target control circuit; finally, based on the first target control circuit, control is performed to prevent the non-isolated LED driver from starting a flashing light.

[0063] The beneficial effect of the above technical solution is: by adopting the solution provided in this embodiment, by taking a synchronous control method, it is ensured that the LED lamp avoids the occurrence of micro-flickering when it is driven on, thereby improving the user experience of the LED lamp.

[0064] In one embodiment, configuring a target control circuit includes:

[0065] Configure the functional modules, LED load, parasitic capacitance and AC power supply of the target control circuit;

[0066] Connect the functional modules, LED load, parasitic capacitance and AC power supply to generate the target control circuit.

[0067] The working principle of the above technical solution is: in order to configure the target control circuit, the present invention first configures the functional module, LED load, parasitic capacitor and AC power supply of the target control circuit; then connects the functional module, LED load, parasitic capacitor and AC power supply to generate the target control circuit.

[0068] The beneficial effect of the above technical solution is: by adopting the solution provided in this embodiment, by configuring and connecting the functional modules, LED loads, parasitic capacitors and AC power supply of the target control circuit, a target control circuit can be generated to provide a basis for realizing various functional controls.

[0069] In one embodiment, the functional modules of the target control circuit are configured, including:

[0070] Configure a power factor correction module, which is used to convert the AC power supply into a DC voltage and ensure a high power factor of the LED drive power supply;

[0071] Configure the afterglow control module, which is used to ensure that the LED load has no afterglow when the LED driver power supply is in standby mode;

[0072] A load conversion control module is configured, and the load conversion control module is used to convert the DC voltage output by the power factor correction module into the current or voltage required by the LED load.

[0073] The working principle of the above technical solution is as follows: in order to configure the functional modules of the target control circuit, the present invention first configures a power factor correction module, which is used to convert the AC power supply into a DC voltage and ensure the high power factor of the LED driving power supply; then configures an afterglow control module, which is used to ensure that the LED load has no afterglow when the LED driving power supply is in standby mode; finally, configures a load conversion control module, which is used to convert the DC voltage output by the power factor correction module into the current or voltage required by the LED load.

[0074] The beneficial effect of the above technical solution is: by adopting the solution provided by this embodiment, by configuring the functional modules of the target control circuit, a basis is provided for realizing the functions of the target control circuit.

[0075] In one embodiment, Figure 2 As shown, the functional module, LED load, parasitic capacitor and AC power supply are connected to generate the target control circuit, including:

[0076] The AC power supply is connected to the power factor correction module, the power factor correction module is connected to the afterglow control module, the afterglow control module is connected to the load conversion control module, the load conversion control module is connected to the LED load, the LED load is connected to the parasitic capacitor, and the parasitic capacitor is connected to the ground wire to generate a target control circuit; for the connection structure of the load conversion control module and the afterglow control module in the target control circuit, such as Figure 3As shown, the power factor correction module can also be first connected to the load conversion control module, and then the load conversion control module is connected to the afterglow control module, and then the afterglow control module is connected to the LED load. The change in the connection structure of the load conversion control module and the afterglow control module in the target control circuit does not change the functional implementation of the target control circuit.

[0077] The working principle of the above technical solution is: in order to connect the functional module, LED load, parasitic capacitor and AC power supply and generate a target control circuit, the present invention connects the AC power supply to the power factor correction module, connects the power factor correction module to the afterglow control module, connects the afterglow control module to the load conversion control module, connects the load conversion control module to the LED load, connects the LED load to the parasitic capacitor, and connects the parasitic capacitor to the ground wire to generate the target control circuit.

[0078] The beneficial effect of the above technical solution is: by adopting the solution provided in this embodiment, by connecting the functional module, the LED load, the parasitic capacitor and the AC power supply, it is possible to ensure that the target control circuit is generated.

[0079] In one embodiment, the functional module of configuring the target control circuit further includes:

[0080] The control chip U2, the power tube Q1, the inductor L1, the diode D1, the capacitor C1, the capacitor C2, the resistor R8, the resistor R9, the resistor R10 and the rectifier bridge BD1 are configured as a power factor correction module;

[0081] Configure relay K1 as afterglow control module;

[0082] The control chip U1, the resistor R1, the resistor R2, the resistor R3, the resistor R6, the resistor R7, the power tube Q3, the inductor L2, the diode D2, the diode D3, the transformer LF1 and the capacitor C3 are configured as a load conversion control module.

[0083] The working principle of the above technical scheme is: in order to configure the functional modules of the target control circuit, the present invention configures the control chip U2, the power tube Q1, the inductor L1, the diode D1, the capacitor C1, the capacitor C2, the resistor R8, the resistor R9, the resistor R10 and the rectifier bridge stack BD1 as a power factor correction module; configures the relay K1 as an afterglow control module; configures the control chip U1, the resistor R1, the resistor R2, the resistor R3, the resistor R6, the resistor R7, the power tube Q3, the inductor L2, the diode D2, the diode D3, the transformer LF1 and the capacitor C3 as a load conversion control module.

[0084] The beneficial effect of the above technical solution is: by adopting the solution provided by this embodiment, the functional modules of the target control circuit are configured to facilitate the realization of the functions of the target control circuit.

[0085] In one embodiment, Figure 4 As shown, the functional modules in the target control circuit are updated in configuration and the connection structure is improved to obtain a first target control circuit, including:

[0086] A synchronous control module is configured between the afterglow control module and the load conversion control module. The synchronous control module includes a power tube Q2, a resistor R4, a resistor R5, a capacitor C4 and a diode D4.

[0087] The working principle of the above technical solution is: in order to realize the configuration update of the functional modules in the target control circuit, the present invention configures a synchronous control module between the afterglow control module and the load conversion control module, and the synchronous control module includes a power tube Q2, a resistor R4, a resistor R5, a capacitor C4 and a diode D4.

[0088] The beneficial effect of the above technical solution is: by adopting the solution provided by this embodiment, a basis for subsequent synchronous control is provided by configuring a synchronous control module.

[0089] In one embodiment, Figure 4 As shown, the configuration of the functional modules in the target control circuit is updated and the connection structure is improved to obtain the first target control circuit, and further includes:

[0090] The afterglow control module is connected to the synchronization control module, and the synchronization control module is connected to the load conversion control module. In this embodiment, the driving signal of the power tube Q3 directly generates a synchronization signal through an analog circuit, specifically:

[0091] One input end of the rectifier bridge stack BD1 is connected to AC_L of the AC power supply, the other input end of the rectifier bridge stack BD1 is connected to AC_N of the AC power supply, one output end of the rectifier bridge stack BD1 is connected to one end of the inductor L1 and one end of the capacitor C1, and the other output end of the rectifier bridge stack BD1 is connected to the other end of the resistor R9 and the other end of the capacitor C1; the other end of the inductor L1 is connected to the anode of the diode D1; the cathode of the diode D1 is connected to one end of the capacitor C2, and the other end of the capacitor C2 is connected to the other end of the resistor R9; the other end of the resistor R9 is grounded; one end of the resistor R9 is connected to the other end of the resistor R10; one end of the resistor R10 is connected to the CS end of the control chip U2, the GND end of the control chip U2 is grounded, and the BATE end of the control chip U2 is connected to one end of the resistor R8; the other end of the resistor R8 is connected to the gate of the power tube Q1, the source of the power tube Q1 is connected to the other end of the resistor R10, and the drain of the power tube Q1 is connected to the anode of the diode D1;

[0092] The cathode of diode D1 is connected to pins 1 and 2 of relay K1;

[0093] Pin 4 of relay K1 is connected to one end of inductor L2 and the cathode of diode D3; the other end of inductor L2 is respectively connected to one end of capacitor C3, one end of resistor R1 and the input end of transformer LF1; the anode of diode D3 is respectively connected to the other end of capacitor C3, the other end of resistor R1 and the output end of transformer LF1; the output end of transformer LF1 is connected to LED load;

[0094] Pin 3 of relay K1 is connected to the collector of power tube Q2, the base of power tube Q2 is connected to one end of resistor R4, the other end of resistor R4 is respectively connected to one end of resistor R5 and the other end of capacitor C4, one end of capacitor C4 is grounded; the other end of resistor R5 is connected to the cathode of diode D4, the anode of diode D4 is connected to the third pulse width modulation signal input end; one end of resistor R4 is connected to the VREALAY signal input end;

[0095] The anode of the diode D3 is connected to the drain of the power tube Q3, and the gate of the power tube Q3 is connected to the anode of the diode D2 and one end of the resistor R2 respectively; the source of the power tube Q3 is connected to one end of the resistor R6 and one end of the resistor R7; the other end of the resistor R6 is grounded, and the other end of the resistor R7 is connected to the CS end of the control chip U1;

[0096] The cathode of the diode D2 is connected to one end of the resistor R3, and the other end of the resistor R3 and the other end of the resistor R2 are connected to the first pulse width modulation signal input end; the first pulse width modulation signal input end is connected to the GA end of the control chip U1, the first pulse width modulation signal is connected to the third pulse width modulation signal, the second pulse width modulation signal input end is connected to the PWM end of the control chip U1, and the GND end of the control chip U1 is grounded;

[0097] In another embodiment, Figure 5 As shown, the synchronous control and external dimming control in this embodiment are implemented by executing software programs. The afterglow control module performs corresponding delays through the software program for synchronization, and can also detect the signal of PWM1 for synchronization. For example, when a pulse signal appears in PWM1, VREALAY is at a high level, and the relay in the afterglow control module is turned on to achieve synchronization.

[0098] The working principle of the above technical solution is: in order to improve the connection structure of the functional modules in the target control circuit, the present invention connects the afterglow control module to the synchronous control module, and connects the synchronous control module to the load conversion control module. The specific circuit connection structure is: one input end of the rectifier bridge stack BD1 is connected to AC_L of the AC power supply, the other input end of the rectifier bridge stack BD1 is connected to AC_N of the AC power supply, one output end of the rectifier bridge stack BD1 is connected to one end of the inductor L1 and one end of the capacitor C1, and the rectifier bridge stack BD1 The other output end is connected to the other end of the resistor R9 and the other end of the capacitor C1; the other end of the inductor L1 is connected to the anode of the diode D1; the cathode of the diode D1 is connected to one end of the capacitor C2, and the other end of the capacitor C2 is connected to the other end of the resistor R9; the other end of the resistor R9 is grounded; one end of the resistor R9 is connected to the other end of the resistor R10; one end of the resistor R10 is connected to the CS end of the control chip U2, the GND end of the control chip U2 is grounded, and the BATE end of the control chip U2 is connected to one end of the resistor R8; the other end of the resistor R8 is connected to the gate of the power tube Q1, the source of the power tube Q1 is connected to the other end of the resistor R10, and the drain of the power tube Q1 is connected to the anode of the diode D1;

[0099] The cathode of diode D1 is connected to pins 1 and 2 of relay K1;

[0100] Pin 4 of relay K1 is connected to one end of inductor L2 and the cathode of diode D3; the other end of inductor L2 is respectively connected to one end of capacitor C3, one end of resistor R1 and the input end of transformer LF1; the anode of diode D3 is respectively connected to the other end of capacitor C3, the other end of resistor R1 and the output end of transformer LF1; the output end of transformer LF1 is connected to LED load;

[0101] Pin 3 of relay K1 is connected to the collector of power tube Q2, the base of power tube Q2 is connected to one end of resistor R4, the other end of resistor R4 is respectively connected to one end of resistor R5 and the other end of capacitor C4, one end of capacitor C4 is grounded; the other end of resistor R5 is connected to the cathode of diode D4, the anode of diode D4 is connected to the third pulse width modulation signal input end; one end of resistor R4 is connected to the VREALAY signal input end;

[0102] The anode of the diode D3 is connected to the drain of the power tube Q3, and the gate of the power tube Q3 is connected to the anode of the diode D2 and one end of the resistor R2 respectively; the source of the power tube Q3 is connected to one end of the resistor R6 and one end of the resistor R7; the other end of the resistor R6 is grounded, and the other end of the resistor R7 is connected to the CS end of the control chip U1;

[0103] The cathode of the diode D2 is connected to one end of the resistor R3, and the other end of the resistor R3 and the other end of the resistor R2 are connected to the first pulse width modulation signal input end; the first pulse width modulation signal input end is connected to the GA end of the control chip U1, the first pulse width modulation signal is connected to the third pulse width modulation signal, the second pulse width modulation signal input end is connected to the PWM end of the control chip U1, and the GND end of the control chip U1 is grounded.

[0104] The beneficial effect of the above technical solution is: by adopting the solution provided by this embodiment, by connecting various functional modules, the realization of the circuit function can be guaranteed, which is conducive to improving the effectiveness of LED control.

[0105] In one embodiment, the second pulse width modulation signal is generated by a preset external dimming control module.

[0106] The working principle of the above technical solution is: by setting an external dimming control module, conditions are provided for the generation of the input signal of the VREALAY signal input terminal and the second pulse width modulation signal.

[0107] The beneficial effect of the above technical solution is: by adopting the solution provided by this embodiment, a synchronization signal is provided for subsequent synchronization control through the input signal of the VREALAY signal input terminal and the second pulse width modulation signal.

[0108] In one embodiment, based on the first target control circuit, the control of preventing the non-isolated LED driver from starting the flashing light includes:

[0109] Connect to AC power;

[0110] After the AC power is rectified by the rectifier bridge BD1, the power factor correction module is driven to start and output a DC voltage;

[0111] Outputting the second pulse width modulation signal generated by the external dimming control module to the control chip U1;

[0112] After the delay of the control chip U1, the first pulse width modulation signal acting on the power tube Q3 is at a low level. At this time, the afterglow control module and the load conversion control module are not started, and no parasitic current flows through the LED load;

[0113] Through the synchronous control module, the third pulse width modulation signal connected to the first pulse width modulation signal is used to control the relay K1 in the afterglow control module to be turned on, so that the power tube Q3 and the relay K1 in the afterglow control module are turned on at the same time, so as to visually avoid the LED light from flickering when starting; Figure 6 , 7 As shown, Figure 6 A schematic diagram of the LED load current waveform under the control of the module based on the target control circuit; Figure 7 A schematic diagram of a LED load current waveform under control of a module based on a first target control circuit;

[0114] This example uses software to achieve synchronization control. The afterglow control module can synchronize by performing corresponding delays through software, or it can detect the first pulse width modulation signal for synchronization. For example, when a pulse signal appears in the first pulse width modulation signal, VREALAY is high, and the afterglow control module is turned on to achieve synchronization.

[0115] The working principle of the above technical solution is: in order to achieve control to prevent the non-isolated LED driver from starting and flashing, the present invention first connects to the AC power supply; after the AC power supply is rectified by the rectifier bridge stack BD1, the power factor correction module is driven to start and output a DC voltage; then the second pulse width modulation signal generated by the external dimming control module is output to the control chip U1; after the delay of the control chip U1, the first pulse width modulation signal acting on the power tube Q3 is a low level, at which time the afterglow control module and the load conversion control module are not started, and no parasitic current flows through the LED load; finally, through the synchronous control module, the third pulse width modulation signal connected to the first pulse width modulation signal is used to control the relay K1 in the afterglow control module to turn on, so as to achieve synchronous conduction of the power tube Q3 and the relay K1 in the afterglow control module or successive conduction within a short time interval, so as to visually avoid the LED light from flashing when starting.

[0116] The beneficial effect of the above technical solution is: by adopting the solution provided in this embodiment, through the control of the control chip U1 and the synchronous control module, it is possible to visually avoid the LED light from flickering when starting.

[0117] In one embodiment, based on the first target control circuit, the control to prevent the non-isolated LED driver from starting the flashing light is performed, and further includes setting a capacitor test circuit to test the capacitance of the capacitor C3, and setting an analog drive control circuit to simulate and determine the driving time of the LED load by using the analog drive control circuit to determine the target capacitance of the capacitor C3, and update the configuration of the load conversion control module; specifically:

[0118] A controller, a capacitance test circuit and an analog drive control circuit are provided, wherein the capacitance test circuit and the analog drive control circuit are both connected to the controller; and the capacitance test circuit is connected to a load conversion control module;

[0119] Using the controller, based on the capacitance test circuit, the capacitance of the capacitor C3 in the load conversion control module is tested to obtain a capacitance test result;

[0120] Using the controller, based on the analog drive control circuit and according to the capacitance test result, a simulated drive test of the drive time of the LED load is performed to obtain a drive time simulation test result;

[0121] According to the driving time simulation test result and the driving time requirement of the LED load, the target driving time in the driving time simulation test result is determined, and the corresponding target capacitance value of the capacitor C3 is determined;

[0122] According to the target capacitance of capacitor C3, the configuration of the load conversion control module is updated.

[0123] The working principle of the above technical solution is as follows: in order to achieve precise control to prevent the non-isolated LED driver from starting the flashing light, the present invention further provides a capacitor test circuit to test the capacitance of the capacitor C3, and provides an analog drive control circuit, and uses the analog drive control circuit to simulate and determine the driving time of the LED load to determine the target capacitance of the capacitor C3, and update the configuration of the load conversion control module; firstly, a controller, a capacitor test circuit and an analog drive control circuit are provided, and the capacitor test circuit and the analog drive control circuit are both connected to the controller; the capacitor test circuit is connected to the load conversion control module; then, the controller is used to test the capacitance of the capacitor C3 in the load conversion control module based on the capacitor test circuit to obtain the capacitance test result; the controller is used to perform a simulated drive test of the driving time of the LED load based on the analog drive control circuit according to the capacitance test result to obtain the driving time simulation test result; finally, according to the driving time simulation test result, according to the driving time requirement of the LED load, the target driving time in the driving time simulation test result is determined, and the corresponding target capacitance of the capacitor C3 is determined; according to the target capacitance of the capacitor C3, the configuration of the load conversion control module is updated.

[0124] The beneficial effect of the above technical solution is: by adopting the solution provided by this embodiment, a capacitor testing circuit is also set to test the capacitance of the capacitor C3, and an analog drive control circuit is set to simulate and determine the driving time of the LED load using the analog drive control circuit to determine the target capacitance of the capacitor C3, and update the configuration of the load conversion control module, thereby ensuring the scientific nature of the configuration of the load conversion control module.

[0125] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for preventing a non-isolated LED driver from starting to flash, characterized in that: include: Configure the target control circuit, which is used to realize the basic control of the non-isolated LED driver to start the flashing light; Updating the configuration and improving the connection structure of the functional modules in the target control circuit to obtain a first target control circuit; Based on the first target control circuit, control is performed to prevent the non-isolated LED driver from starting the flashing light; Configure the target control circuit, including: Configure the functional modules, LED load, parasitic capacitance and AC power supply of the target control circuit; Connect the functional modules, LED loads, parasitic capacitors and AC power supply to generate the target control circuit; Configure the functional modules of the target control circuit, including: Configure a power factor correction module, which is used to convert the AC power supply into a DC voltage and ensure a high power factor of the LED drive power supply; Configure the afterglow control module, which is used to ensure that the LED load has no afterglow when the LED driver power supply is in standby mode; A load conversion control module is configured, and the load conversion control module is used to convert the DC voltage output by the power factor correction module into the current or voltage required by the LED load; The function modules in the target control circuit are updated in configuration and their connection structures are improved to obtain a first target control circuit, including: A synchronous control module is configured between the afterglow control module and the load conversion control module. The synchronous control module includes a power tube Q2, a resistor R4, a resistor R5, a capacitor C4 and a diode D4.

2. A method for preventing a non-isolated LED driver from starting to flash according to claim 1, characterized in that: Connect functional modules, LED loads, parasitic capacitors, and AC power to generate the target control circuit, including: Connect the AC power supply to the power factor correction module, connect the power factor correction module to the afterglow control module, connect the afterglow control module to the load conversion control module, connect the load conversion control module to the LED load, connect the LED load to the parasitic capacitor, connect the parasitic capacitor to the ground wire, and generate a target control circuit.

3. A method for preventing a non-isolated LED driver from starting to flash according to claim 1, characterized in that: The functional module for configuring the target control circuit also includes: The control chip U2, the power tube Q1, the inductor L1, the diode D1, the capacitor C1, the capacitor C2, the resistor R8, the resistor R9, the resistor R10 and the rectifier bridge BD1 are configured as a power factor correction module; Configure relay K1 as afterglow control module; The control chip U1, the resistor R1, the resistor R2, the resistor R3, the resistor R6, the resistor R7, the power tube Q3, the inductor L2, the diode D2, the diode D3, the transformer LF1 and the capacitor C3 are configured as a load conversion control module.

4. A method for preventing a non-isolated LED driver from starting to flash according to claim 1, characterized in that: The configuration of the functional modules in the target control circuit is updated and the connection structure is improved to obtain a first target control circuit, and the method further includes: The afterglow control module is connected to the synchronous control module, and the synchronous control module is connected to the load conversion control module, specifically: One input end of the rectifier bridge stack BD1 is connected to AC_L of the AC power supply, the other input end of the rectifier bridge stack BD1 is connected to AC_N of the AC power supply, one output end of the rectifier bridge stack BD1 is connected to one end of the inductor L1 and one end of the capacitor C1, and the other output end of the rectifier bridge stack BD1 is connected to the other end of the resistor R9 and the other end of the capacitor C1; the other end of the inductor L1 is connected to the anode of the diode D1; the cathode of the diode D1 is connected to one end of the capacitor C2, and the other end of the capacitor C2 is connected to the other end of the resistor R9; the other end of the resistor R9 is grounded; one end of the resistor R9 is connected to the other end of the resistor R10; one end of the resistor R10 is connected to the CS end of the control chip U2, the GND end of the control chip U2 is grounded, and the BATE end of the control chip U2 is connected to one end of the resistor R8; the other end of the resistor R8 is connected to the gate of the power tube Q1, the source of the power tube Q1 is connected to the other end of the resistor R10, and the drain of the power tube Q1 is connected to the anode of the diode D1; The cathode of diode D1 is connected to pins 1 and 2 of relay K1; Pin 4 of relay K1 is connected to one end of inductor L2 and the cathode of diode D3; the other end of inductor L2 is respectively connected to one end of capacitor C3, one end of resistor R1 and the input end of transformer LF1; the anode of diode D3 is respectively connected to the other end of capacitor C3, the other end of resistor R1 and the output end of transformer LF1; the output end of transformer LF1 is connected to LED load; Pin 3 of relay K1 is connected to the collector of power tube Q2, the base of power tube Q2 is connected to one end of resistor R4, the other end of resistor R4 is respectively connected to one end of resistor R5 and the other end of capacitor C4, one end of capacitor C4 is grounded; the other end of resistor R5 is connected to the cathode of diode D4, the anode of diode D4 is connected to the third pulse width modulation signal input end; one end of resistor R4 is connected to the VREALAY signal input end; The anode of the diode D3 is connected to the drain of the power tube Q3, and the gate of the power tube Q3 is connected to the anode of the diode D2 and one end of the resistor R2 respectively; the source of the power tube Q3 is connected to one end of the resistor R6 and one end of the resistor R7; the other end of the resistor R6 is grounded, and the other end of the resistor R7 is connected to the CS end of the control chip U1; The cathode of the diode D2 is connected to one end of the resistor R3, and the other end of the resistor R3 and the other end of the resistor R2 are connected to the first pulse width modulation signal input end; the first pulse width modulation signal input end is connected to the GA end of the control chip U1, the first pulse width modulation signal is connected to the third pulse width modulation signal, the second pulse width modulation signal input end is connected to the PWM end of the control chip U1, and the GND end of the control chip U1 is grounded.

5. A method for preventing a non-isolated LED driver from starting to flash according to claim 4, characterized in that: The second pulse width modulation signal is generated by a preset external dimming control module.

6. A method for preventing a non-isolated LED driver from starting to flash according to claim 4, characterized in that: Based on the first target control circuit, control is performed to prevent the non-isolated LED driver from starting the flashing light, including: Connect to AC power; After the AC power is rectified by the rectifier bridge BD1, the power factor correction module is driven to start and output a DC voltage; Outputting the second pulse width modulation signal generated by the external dimming control module to the control chip U1; After the delay of the control chip U1, the first pulse width modulation signal acting on the power tube Q3 is at a low level. At this time, the afterglow control module and the load conversion control module are not started, and no parasitic current flows through the LED load; Through the synchronous control module, a third pulse width modulation signal connected to the first pulse width modulation signal is used to control the relay K1 in the afterglow control module to be turned on, so that the power tube Q3 and the relay K1 in the afterglow control module are turned on at the same time, so as to visually avoid the LED lamp from flickering when it starts.

7. A method for preventing a non-isolated LED driver from starting to flash according to claim 1, characterized in that: Based on the first target control circuit, the control of preventing the non-isolated LED driver from starting the flashing light is performed, and the method further includes setting a capacitor test circuit to test the capacitance of the capacitor C3, and setting an analog drive control circuit to simulate and determine the driving time of the LED load using the analog drive control circuit to determine the target capacitance of the capacitor C3, and updating the configuration of the load conversion control module; specifically: A controller, a capacitance test circuit and an analog drive control circuit are provided, wherein the capacitance test circuit and the analog drive control circuit are both connected to the controller; and the capacitance test circuit is connected to a load conversion control module; Using the controller, based on the capacitance test circuit, the capacitance of the capacitor C3 in the load conversion control module is tested to obtain a capacitance test result; Using the controller, based on the analog drive control circuit and according to the capacitance test result, a simulated drive test of the drive time of the LED load is performed to obtain a drive time simulation test result; According to the driving time simulation test results and the driving time requirement of the LED load, the target driving time in the driving time simulation test results is determined, and the corresponding target capacitance value of the capacitor C3 is determined; According to the target capacitance of capacitor C3, the configuration of the load conversion control module is updated.

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