LED light-adjusting driving power supply

Abstract

The application discloses an LED dimming driving power supply, which comprises a front-stage circuit, a voltage transformation unit and a rear-stage circuit, the rear-stage circuit is electrically connected with a light source assembly, and the front-stage circuit comprises a filter input unit, a resistance-capacitance unit, a first switch unit, a voltage signal conditioning unit, a power switch unit, a first voltage division unit, a trigger unit and a control unit. When the AC input voltage changes, the working state of the trigger unit changes, the power switch unit is triggered to be turned off or turned on, the control unit controls the conduction state or conduction parameter of the first switch unit according to the input voltage waveform, and the resistance-capacitance unit is cooperated to solve the flickering problem caused by the early turn-off of the thyristor when the phase-cut angle is small, the flash problem caused by the incomplete turn-off of the thyristor, and the direct start without flash when the thyristor is turned on again.

Description

Technical Field

[0001] This invention relates to the field of thyristor dimming technology, and in particular to an LED dimming driver power supply. Background Technology

[0002] A thyristor dimmer is a lighting accessory that uses a thyristor as a switching device to control brightness by phase cutting, thereby changing the luminous flux of an electric light source and adjusting the illuminance. It has a simple circuit, low cost, and good compatibility with traditional incandescent lamps.

[0003] However, when thyristors are used to drive LED lights, flickering often occurs due to the input characteristics of the LED driver power supply. This is mainly due to the following factors: 1. After the thyristor is turned on, a current greater than the set value (i.e., holding current) needs to be maintained across its terminals to ensure continuous conduction. Traditional incandescent lamps are resistive, which meets the conduction conditions of the thyristor. However, the driver power supply generally includes a large number of capacitive loads, making the circuit unstable and prone to "flickering" or "partially off" states. 2. Thyristors are prone to oscillation during restart, which can lead to false triggering. Therefore, before normal lighting, a flickering phenomenon may occur before the thyristor turns on. 3. When the thyristor is switched at a small angle, due to insufficient holding current, the thyristor may turn off prematurely, causing flickering.

[0004] The purpose of this application is to provide an LED dimming driver power supply that solves at least one of the above-mentioned problems. Summary of the Invention

[0005] The purpose of this invention is to provide an LED dimming driver power supply to overcome the shortcomings of the above-mentioned technologies.

[0006] The present invention provides an LED dimming driver power supply, comprising a pre-stage circuit, a transformer unit, and a post-stage circuit connected in sequence. The output terminal of the post-stage circuit is electrically connected to the light source assembly. The pre-stage circuit includes a filter input unit, a resistor-capacitor unit, a first switching unit, a voltage signal conditioning unit, a power switching unit, a first voltage divider unit, a trigger unit, and a control unit. The input terminal of the filter input unit is electrically connected to the AC power supply, the output terminal of the filter input unit is electrically connected to the voltage signal conditioning unit, the other end of the voltage signal conditioning unit is electrically connected to the control unit, the control terminal of the first switching unit is electrically connected to the control unit, the first terminal of the first switching unit is electrically connected to the voltage signal conditioning unit, the second terminal of the first switching unit is electrically connected to the output terminal of the filter input unit and the resistor-capacitor unit, the resistor-capacitor unit is connected to the output terminal of the filter input unit, the first voltage divider unit and the trigger unit are connected in series and then connected to the output terminal of the filter input unit, the control terminal of the power switching unit is electrically connected to the connection point of the first voltage divider unit and the trigger unit, the first terminal of the power switching unit is electrically connected to one end of the first voltage divider unit and the transformer unit, and the second terminal of the power switching unit is electrically connected to the control unit. The filter input unit outputs a chopped AC input voltage. The voltage signal conditioning unit transmits the phase-cut input voltage waveform to the control unit. When the phase-cutting angle of the thyristor is less than the first set angle, the AC input voltage drops to the corresponding first set voltage and is divided by the first voltage divider unit and applied to the trigger unit. The trigger unit changes its operating state to trigger the power switch unit to turn off. The control unit, based on the turn-off signal and the input voltage waveform, outputs a first control signal to adjust the conduction parameters of the first switch unit, and works with the RC unit to adjust the input impedance to provide a sustaining current to the thyristor. When the thyristor is turned off, the trigger unit changes its operating state to trigger the power switch unit to turn off. The control unit, based on the turn-off signal and the input voltage waveform, outputs a second control signal to the first switch unit to turn it off, and the light source assembly immediately turns off. When the thyristor is turned back on and the AC input voltage rises to the second set voltage, the trigger unit changes its operating state to trigger the power switch unit to turn on. The control unit, based on the turn-on signal and the input voltage waveform, outputs a third control signal to the first switch unit to turn it on, and the light source assembly immediately turns on.

[0007] The control unit analyzes and smooths the voltage waveform through the voltage signal conditioning unit to calculate the phase-cutting angle. Based on the phase-cutting angle, it adjusts the PWM duty cycle and peak current. The first switching unit, in conjunction with the RC unit, provides a sustaining current at small angles to keep the thyristor conducting. This allows for advance knowledge of the input voltage information, facilitating timely adjustments and resulting in a smoother response while avoiding flickering. The first voltage divider unit acquires the unbuffered DC bus voltage. When the voltage across the trigger unit is higher than the set voltage, the trigger unit and power switch unit turn on. The voltage drops sharply at small angles or the moment the thyristor turns off. When the voltage across the trigger unit is lower than the set voltage, the trigger unit and power switch unit turn off, resolving the issue of incomplete off.

[0008] Preferably, the LED dimming driver power supply further includes a compensation unit, a second switching unit, and a voltage feedback unit; the input terminal of the compensation unit is electrically connected to the control unit, the compensation unit is connected in parallel with the second switching unit and then electrically connected to the voltage feedback unit, the voltage feedback unit is electrically connected to the subsequent circuit, and the second switching unit is electrically connected to the control unit. When the thyristor is turned on again, the control unit outputs a fourth control signal to the second switching unit to turn it on; when the AC input voltage rises to the second set voltage, the control unit outputs a fifth control signal to the second switching unit to turn it off.

[0009] During system startup, the second switching unit is activated to accelerate the transient response, allowing the light source impedance to immediately reach stable brightness and eliminating flicker during startup, thus achieving fast and flicker-free startup. When the system stabilizes, the second switching unit is deactivated to allow the feedback loop to operate normally, ensuring stability and preventing flickering during operation. The loop speed is switched by adjusting the on / off state of the second switching unit, and the output PWM duty cycle is adjusted through feedback compensation to stabilize the output voltage, ensuring normal operation even under small loads, and preventing flickering even with a small phase-cutting angle.

[0010] Preferably, the LED dimming driver power supply further includes a zero-crossing detection unit, which is electrically connected to the second primary coil of the control unit and the transformer unit respectively.

[0011] Preferably, the LED dimming driver power supply further includes a voltage regulator unit that is electrically connected to the zero-crossing detection unit, the compensation unit, and the control unit.

[0012] By detecting the zero-crossing point of the voltage of the second primary coil of the transformer unit, an accurate starting point is provided for the PWM timing of the control unit, so that the drive power supply switches at the zero current point, reducing switching losses and noise. The voltage regulator unit provides a stable, clean DC voltage reference that is unaffected by grid voltage fluctuations for the compensation unit and the control unit, in order to prevent voltage spikes.

[0013] Preferably, the LED dimming driver power supply further includes a current acquisition unit, which is electrically connected to the voltage regulation unit, the compensation unit, and the control unit. This serves two purposes: firstly, it provides overcurrent protection for the control unit; secondly, it provides feedback for PWM control, ensuring that the peak current in each cycle is controlled, thereby stabilizing the output.

[0014] Preferably, the LED dimming driver power supply further includes an absorption clamping unit, which is disposed between the first voltage divider unit and the first primary coil of the transformer unit. The absorption clamping unit is also electrically connected to the power switch unit and the subsequent circuit.

[0015] By effectively clamping voltage spikes, protecting the power switching unit voltage from exceeding its withstand voltage value, and purifying the system's operating environment, the purity of feedback and control signals is ensured, thereby indirectly guaranteeing a flicker-free dimming effect.

[0016] Preferably, an absorption buffer unit is also included, which is electrically connected to the first primary coil of the trigger unit, the power switch unit, and the transformer unit, respectively. This absorption buffer for the power switch unit reduces EMI interference when the power switch unit is turned on and off.

[0017] Preferably, the voltage signal conditioning unit includes a first capacitor, a second capacitor, a varistor, a fifth resistor, a sixth resistor, a seventh resistor, and a fifth capacitor; the first switching unit includes a first switching transistor, and the RC unit includes a first resistor and a third capacitor; The first capacitor and the first resistor are connected in series and their two ends are electrically connected to the output terminal of the filter input unit. One end of the output terminal of the filter input unit is electrically connected to the ground terminal. The second capacitor and the varistor are connected in parallel across the first capacitor and the first resistor. The control terminal of the first switch is electrically connected to the control unit. The first end of the first switch is electrically connected to the connection point of the first capacitor and the first resistor. The second end of the first switch is electrically connected to the ground terminal. A third capacitor is connected in series between the control terminal and the second end of the first switch. The fifth and sixth resistors are connected in series, with one end connected to the output terminal of the filter input unit and the other end electrically connected to the control unit. A seventh resistor and a fifth capacitor are connected in parallel between the sixth resistor and the ground terminal.

[0018] Preferably, the first voltage divider unit includes a second resistor and a third resistor, the trigger unit is a Zener diode, and the power switch unit includes a second switch transistor, a fourth resistor, a fourth capacitor, a first diode, and a second diode. The second resistor, the third resistor, and the Zener diode are connected in series in sequence. One end of the first resistor is electrically connected to one end of the output terminal of the filter input unit, and the other end is electrically connected to the other end of the output terminal of the filter input unit. A fourth resistor is connected in series between the control terminal of the second switch and the connection point of the third resistor and the Zener diode. A first diode is connected in parallel across the two ends of the fourth resistor. A fourth capacitor is connected in series between the cathode of the first diode and the anode of the Zener diode. The first end of the second switch is electrically connected to the first primary coil of the transformer unit and the absorption clamping unit, respectively. A second diode is connected in series between the cathode of the first diode and the second end of the second switch. The second end of the second switch is electrically connected to the control unit.

[0019] Preferably, the zero-crossing detection unit includes a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a fifth diode, and a ninth capacitor. The ninth, tenth, and eleventh resistors are connected in series, with one end electrically connected to one end of the second primary coil of the transformer unit and the other end electrically connected to the control unit. The fifth diode, the ninth capacitor, and the twelfth resistor are connected in parallel at the connection point of the tenth and eleventh resistors. The other end of the second primary coil of the transformer unit is grounded.

[0020] Preferably, the voltage regulator unit includes a third diode, a third switching transistor, a fourth diode, a sixth capacitor, a seventh capacitor, an eighth capacitor, and an eighth resistor; the third diode, the eighth resistor, and the fourth diode are connected in series, with one end electrically connected to the connection point of the ninth and tenth resistors, and the other end grounded; the control terminal of the third switching transistor is electrically connected to the connection point of the eighth resistor and the fourth diode; the first terminal of the third switching transistor is connected in series with the sixth capacitor and then electrically connected to the control unit; the sixth capacitor is electrically connected to the positive terminal of the fourth diode; and the second terminal of the third switching transistor is connected in series with the ground terminal with the eighth capacitor and the seventh capacitor connected in parallel.

[0021] This invention provides an LED dimming driver power supply. By changing the operating state of the trigger unit when the AC input voltage changes, the power switch unit is triggered to turn off or on. The control unit controls the conduction state or conduction parameters of the first switch unit in conjunction with the input voltage waveform. This works in conjunction with the resistor-capacitor unit to ensure that the thyristor can be turned off quickly without causing the flickering problem of being partially turned off. When it is turned on again, it can be turned on directly without flickering. At the same time, under small load conditions and small phase angle, it avoids premature turn-off and maintains stability without flickering. This ensures stable operation under various loads and phase angles, providing a stable and flicker-free dimming experience. Attached Figure Description

[0022] Figure 1 This is a structural principle block diagram of an LED dimming driver power supply provided by the present invention; Figure 2 yes Figure 1 The circuit schematic in the image.

[0023] The attached figures are labeled as follows: 1. Filter input unit; 2. RC unit; 3. First switching unit; 4. Voltage signal conditioning unit; 5. Power switching unit; 6. First voltage divider unit; 7. Trigger unit; 8. Control unit; 9. AC power supply; 10. Compensation unit; 11. Second switching unit; 12. Zero-crossing detection unit; 13. Voltage regulation unit; 14. Current acquisition unit; 15. Absorption clamping unit; 16. Absorption buffer unit; 17. Voltage feedback unit; 100. Pre-amplifier circuit; 200. Transformer unit; 300. Power-up circuit; 400. Light source assembly. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the scope of protection of the present invention.

[0025] In this embodiment, as Figure 1-2 As shown, the present invention discloses an LED dimming driver power supply, including a front-end circuit 100, a transformer unit 200 and a rear-end circuit 300 connected in sequence. The output terminal of the rear-end circuit 300 is electrically connected to the light source assembly 400. The front-end circuit 100 includes a filter input unit 1, a resistor-capacitor unit 2, a first switching unit 3, a voltage signal conditioning unit 4, a power switching unit 5, a first voltage divider unit 6, a trigger unit 7 and a control unit 8. The input terminal of the filter input unit 1 is electrically connected to the AC power supply 9, the output terminal of the filter input unit 1 is electrically connected to the voltage signal conditioning unit 4, the other end of the voltage signal conditioning unit 4 is electrically connected to the control unit 8, the control terminal of the first switch unit 3 is electrically connected to the control unit 8, the first end of the first switch unit 3 is electrically connected to the voltage signal conditioning unit 4, the second end of the first switch unit 3 is electrically connected to the output terminal of the filter input unit 1 and the resistor-capacitor unit 2, the resistor-capacitor unit 2 is connected to the output terminal of the filter input unit 1, the first voltage divider unit 6 and the trigger unit 7 are connected in series to the output terminal of the filter input unit 1, the control terminal of the power switch unit 5 is electrically connected to the connection point of the first voltage divider unit 6 and the trigger unit 7, the first end of the power switch unit 5 is electrically connected to one end of the first voltage divider unit 6 and the transformer unit 200, and the second end of the power switch unit 5 is electrically connected to the control unit 8. The filter input unit 1 outputs a chopped AC input voltage, and the voltage signal conditioning unit 4 transmits the phase-cut input voltage waveform to the control unit 8. When the phase-cutting angle of the thyristor is less than the first set angle, the AC input voltage drops to the corresponding first set voltage and is divided by the first voltage divider unit and applied to the trigger unit. The trigger unit 7 changes its operating state to trigger the power switch unit 5 to turn off. The control unit 8, based on the turn-off signal and the input voltage waveform, outputs a first control signal to adjust the conduction parameters of the first switch unit 3, and works with the RC unit 2 to adjust the input impedance, providing a sustaining current to the thyristor to prevent premature turn-off at small angles. When the thyristor turns off, the trigger unit 7 changes its operating state to trigger the power switch unit 5 to turn off, and the control unit 8, based on the turn-off signal and the input voltage waveform, outputs a second control signal to the first switch unit 3 to turn it off, and the light source assembly 400 immediately shuts off. When the thyristor is turned on again and the AC input voltage rises to the second set voltage, the trigger unit 7 changes its working state to trigger the power switch unit 5 to turn on. The control unit 8 outputs a third control signal to the first switch unit 3 based on the turn-on signal and the input voltage waveform to turn it on, and the light source assembly 400 turns on immediately.

[0026] The voltage signal conditioning unit 4 includes a first capacitor C3, a second capacitor C3A, a varistor RV2, a fifth resistor R7, a sixth resistor R35, a seventh resistor R12, and a fifth capacitor C9; the first switching unit 3 includes a first switching transistor Q1, and the RC unit 2 includes a first resistor R6 and a third capacitor C4; the first capacitor C3 and the first resistor R6 are connected in series and their two ends are electrically connected to the output terminal of the filter input unit 1, and one end of the output terminal of the filter input unit 1 is electrically connected to the ground terminal; the second capacitor C3A and the varistor RV2 are connected in parallel across the first capacitor C3 and the first resistor R6; the control terminal of the first switching transistor Q1 is electrically connected to the control unit 8; the first end of the first switching transistor Q1 is electrically connected to the connection point of the first capacitor C3 and the first resistor R6; the second end of the first switching transistor Q1 is electrically connected to the ground terminal; and the third capacitor C4 is connected in series between the control terminal and the second end of the first switching transistor Q1.

[0027] The fifth resistor R7 and the sixth resistor R35 are connected in series. One end of R7 is connected to the output terminal of the filter input unit 1, which is the connection point of the second capacitor C3A and the varistor RV2. The other end of R35 is electrically connected to the control unit 8. A seventh resistor R12 and a fifth capacitor C9 are connected in parallel between the sixth resistor R35 and the ground terminal. The fifth resistor R7 and the sixth resistor R35 are pull-up voltage divider resistors, and the seventh resistor R12 and the fifth capacitor C9 are pull-down voltage divider resistors and filters. The first capacitor C3, the second capacitor C3A, and the varistor RV2 work together to detect changes in the phase angle and the input voltage. The fifth resistor R7, the sixth resistor R35, the seventh resistor R12, and the fifth capacitor C9 are used to condition the detected signal for accurate identification by the control unit 8.

[0028] The first voltage divider unit 6 includes a second resistor R9 and a third resistor R8. The trigger unit 7 is a Zener diode ZD1. The power switch unit 5 includes a second switch Q3, a fourth resistor R10, a fourth capacitor C7, a first diode D2, and a second diode D4. The second resistor R9, the third resistor R8, and the Zener diode ZD1 are connected in series, with one end electrically connected to one end of the output terminal of the filter input unit 1, and the other end electrically connected to the other end of the output terminal of the filter input unit 1. The control terminal of the second switch Q3 is connected to the third resistor R8 and the Zener diode. A fourth resistor R10 is connected in series between the connection points of ZD1. A first diode D2 is connected in parallel across the two ends of the fourth resistor R10. A fourth capacitor C7 is connected in series between the cathode of the first diode D2 and the anode of the Zener diode ZD1. The first terminal of the second switch Q3 is electrically connected to the first primary coil of the transformer unit 200 and the absorption clamping unit 15, respectively. A second diode D4 is connected in series between the cathode of the first diode D2 and the second terminal of the second switch Q3. The second terminal of the second switch Q3 is electrically connected to the internal MOS of the control chip U1 of the control unit 8.

[0029] The second resistor R9 and the third resistor R8 are pull-up voltage dividers that supply power to the second switch Q3. The Zener diode ZD1 and the fourth capacitor C7 provide voltage regulation and protection for the gate (G) of the second switch Q3. The first diode D2 quickly turns off the second switch Q3 when it is off, and the second diode D4 acts as a negative voltage clamp. When the DC bus voltage drops, causing the Zener diode ZD1 to turn off, the second switch Q3 turns off. The control unit 8 controls the first switch Q1 to turn off based on this turn-off signal and the input voltage waveform. When the DC bus voltage recovers, causing the Zener diode ZD1 to turn on, the second switch Q3 turns on. The control unit 8 controls the first switch Q1 to turn on based on this turn-on signal and the input voltage waveform.

[0030] The LED dimming driver power supply also includes a compensation unit 10, a second switching unit 11, and a voltage feedback unit 17. The input terminal of the compensation unit 10 is electrically connected to the control unit 8. The compensation unit 10 is connected in parallel with the second switching unit 11 and then electrically connected to the voltage feedback unit 17. The voltage feedback unit 17 is electrically connected to the subsequent circuit 300. The second switching unit 11 is electrically connected to the control unit 8. The LED dimming driver power supply also includes a voltage regulator unit 13 and a zero-crossing detection unit 12 connected to each other. The zero-crossing detection unit 12 is electrically connected to the control unit 8 and the second primary coil of the transformer unit 200, respectively. The voltage regulator unit 13 is electrically connected to the compensation unit 10 and the control unit 8, respectively.

[0031] When the thyristor is turned on again, the control unit 8 outputs a fourth control signal to the second switch unit 11 to turn it on; when the AC input voltage rises to the second set voltage, the control unit 8 outputs a fifth control signal to the second switch unit 11 to turn it off.

[0032] The zero-crossing detection unit 12 includes a ninth resistor R11, a tenth resistor R5, an eleventh resistor R14, a twelfth resistor R16, a fifth diode D6, and a ninth capacitor C12. The ninth resistor R11, tenth resistor R5, and eleventh resistor R14 are connected in series, with one end electrically connected to one end of the second primary coil of the transformer unit 200, and the other end electrically connected to the control unit 8. The fifth diode D6, ninth capacitor C12, and twelfth resistor R16 are connected in parallel at the connection point of the tenth resistor R5 and the eleventh resistor R14. The other end of the second primary coil of the transformer unit 200 is grounded. It is used to detect the auxiliary winding voltage divider of the transformer TR1. The ninth resistor R11 and tenth resistor R5 are pull-up voltage divider resistors, and the eleventh resistor R14 is used by the control chip U1 to detect the RCD, realizing output overvoltage detection, flyback QR valley conduction detection, and PF value adjustment detection.

[0033] The voltage regulator unit 13 includes a third diode D3, a third switch Q2, a fourth diode ZD2, a sixth capacitor C5, a seventh capacitor C18, an eighth capacitor C8, and an eighth resistor R15. The third diode D3, the eighth resistor R15, and the fourth diode ZD2 are connected in series, with one end electrically connected to the connection point of the ninth resistor R11 and the tenth resistor R5, and the other end grounded. The control terminal of the third switch Q2 is electrically connected to the connection point of the eighth resistor R15 and the fourth diode ZD2. The first terminal of the third switch Q2 is connected in series with the sixth capacitor C5 and then electrically connected to the control unit 8. The sixth capacitor C5 is electrically connected to the positive terminal of the fourth diode ZD2. The second terminal of the third switch Q2 is connected in series with the ground terminal, with the eighth capacitor C8 and the seventh capacitor C18 connected in parallel.

[0034] Control unit 8 determines the conduction duration based on the error signal from compensation unit 10 and the conduction time based on the synchronization signal from zero-crossing detection unit 12. Capacitor C10 in compensation unit 10 is used to filter high-frequency noise and provide phase compensation, ensuring loop stability. When the system is first powered on, the voltage across C10 cannot change abruptly. The second switching unit 11 turns on, short-circuiting capacitor C10, effectively eliminating the large capacitor C10 in the feedback loop. The loop response is very fast, allowing control unit 8 to quickly receive the feedback signal and make adjustments, enabling the output voltage to reach the second set voltage quickly and smoothly. The light source component 400 is directly and quickly illuminated, avoiding slow rise and initial flickering. When the system detects that the output voltage has reached the second set voltage, the second switching unit 11 turns off, and capacitor C10 operates normally, suppressing high-frequency noise and providing appropriate phase margin. This ensures the entire feedback system is very stable in steady-state operation, without oscillation or low-frequency jitter, guaranteeing circuit stability under various operating conditions such as low loads.

[0035] The LED dimming driver power supply also includes a current acquisition unit 14, which is electrically connected to the voltage regulator unit 13, the compensation unit 10, and the control unit 8. It also includes an absorption clamping unit 15, which is positioned between the first voltage divider unit 6 and the first primary coil of the transformer unit 200. The absorption clamping unit 15 is also electrically connected to the power switch unit 5 and the subsequent circuit 300. Furthermore, it includes an absorption buffer unit 16, which is electrically connected to the trigger unit 7, the power switch unit 5, and the first primary coil of the transformer unit 200.

[0036] This invention is not limited to the preferred embodiments described above. Anyone can derive other products in various forms under the guidance of this invention. However, regardless of any changes in shape or structure, any technical solution that is the same as or similar to this application falls within the protection scope of this invention.

Claims

1. An LED dimming driver power supply, comprising a pre-stage circuit (100), a transformer unit (200), and a post-stage circuit (300) connected in sequence, wherein the output terminal of the post-stage circuit (300) is electrically connected to a light source assembly (400), characterized in that: The preamplifier circuit (100) includes a filter input unit (1), a resistor-capacitor unit (2), a first switching unit (3), a voltage signal conditioning unit (4), a power switching unit (5), a first voltage divider unit (6), a trigger unit (7), and a control unit (8). The input terminal of the filter input unit (1) is electrically connected to the AC power supply (9), the output terminal of the filter input unit (1) is electrically connected to the voltage signal conditioning unit (4), the other end of the voltage signal conditioning unit (4) is electrically connected to the control unit (8), the control terminal of the first switch unit (3) is electrically connected to the control unit (8), the first end of the first switch unit (3) is electrically connected to the voltage signal conditioning unit (4), the second end of the first switch unit (3) is electrically connected to the output terminal of the filter input unit (1) and the resistor-capacitor unit (2), the resistor-capacitor unit (2) is connected to the output terminal of the filter input unit (1), the first voltage divider unit (6) and the trigger unit (7) are connected in series to the output terminal of the filter input unit (1), the control terminal of the power switch unit (5) is electrically connected to the connection point of the first voltage divider unit (6) and the trigger unit (7), the first end of the power switch unit (5) is electrically connected to one end of the first voltage divider unit (6) and the transformer unit (200), and the second end of the power switch unit (5) is electrically connected to the control unit (8). The filter input unit (1) outputs a chopper-processed AC input voltage. The voltage signal conditioning unit (4) transmits the phase-cut input voltage waveform to the control unit (8). When the phase-cutting angle of the thyristor is less than the first set angle, the AC input voltage drops to the corresponding first set voltage and is divided by the first voltage divider unit (6) and applied to the trigger unit (7). The trigger unit (7) changes its operating state to trigger the power switch unit (5) to turn off. The control unit (8) outputs a first control signal based on the turn-off signal and the input voltage waveform to adjust the conduction parameters of the first switch unit (3). This, in conjunction with the resistor-capacitor unit (2), adjusts the input impedance to provide power to the thyristor. The thyristor provides a sustaining current; when the thyristor is turned off, the trigger unit (7) changes its operating state to trigger the power switch unit (5) to turn off, and the control unit (8) outputs a second control signal to the first switch unit (3) to turn it off based on the turn-off signal and the input voltage waveform, and the light source assembly (400) is immediately turned off; when the thyristor is turned on again and the AC input voltage rises to the second set voltage, the trigger unit (7) changes its operating state to trigger the power switch unit (5) to turn on, and the control unit (8) outputs a third control signal to the first switch unit (3) to turn it on based on the turn-on signal and the input voltage waveform, and the light source assembly (400) is immediately turned on.

2. The LED dimming driver power supply as described in claim 1, characterized in that: The LED dimming driver power supply also includes a compensation unit (10), a second switching unit (11), and a voltage feedback unit (17); the input terminal of the compensation unit (10) is electrically connected to the control unit (8), the compensation unit (10) is connected in parallel with the second switching unit (11) and then electrically connected to the voltage feedback unit (17), the voltage feedback unit (17) is electrically connected to the subsequent circuit (300), and the second switching unit (11) is electrically connected to the control unit (8); When the thyristor is turned on again, the control unit (8) outputs a fourth control signal to the second switch unit (11) to turn it on; when the AC input voltage rises to the second set voltage, the control unit (8) outputs a fifth control signal to the second switch unit (11) to turn it off.

3. The LED dimming driver power supply as described in claim 2, characterized in that: The LED dimming driver power supply also includes a zero-crossing detection unit (12), which is electrically connected to the second primary coil of the control unit (8) and the transformer unit (200).

4. The LED dimming driver power supply as described in claim 3, characterized in that: The LED dimming driver power supply also includes a voltage regulator unit (13) that is electrically connected to the zero-crossing detection unit (12), the compensation unit (10), and the control unit (8).

5. The LED dimming driver power supply as described in claim 4, characterized in that: The LED dimming driver power supply also includes a current acquisition unit (14), which is electrically connected to the voltage regulator unit (13), the compensation unit (10), and the control unit (8).

6. The LED dimming driver power supply as described in claim 1, characterized in that: The LED dimming driver power supply also includes an absorption clamping unit (15), which is located between the first voltage divider unit (6) and the first primary coil of the transformer unit (200). The absorption clamping unit (15) is also electrically connected to the power switch unit (5) and the subsequent circuit (300).

7. The LED dimming driver power supply as described in claim 1, characterized in that: It also includes an absorption buffer unit (16), which is electrically connected to the first primary coil of the trigger unit (7), the power switch unit (5) and the transformer unit (200).

8. The LED dimming driver power supply according to any one of claims 1-7, characterized in that: The voltage signal conditioning unit (4) includes a first capacitor, a second capacitor, a varistor, a fifth resistor, a sixth resistor, a seventh resistor, and a fifth capacitor; the first switching unit (3) includes a first switching transistor, and the resistor-capacitor unit (2) includes a first resistor and a third capacitor; The first capacitor and the first resistor are connected in series and their two ends are electrically connected to the output end of the filter input unit (1). One end of the output end of the filter input unit (1) is electrically connected to the ground end. The second capacitor and the varistor are connected in parallel across the first capacitor and the first resistor. The control end of the first switch is electrically connected to the control unit (8). The first end of the first switch is electrically connected to the connection point of the first capacitor and the first resistor. The second end of the first switch is electrically connected to the ground end. A third capacitor is connected in series between the control end of the first switch and its second end. The fifth resistor and the sixth resistor are connected in series in sequence. One end of the resistor is connected to the output end of the filter input unit (1), and the other end is electrically connected to the control unit (8). A seventh resistor and a fifth capacitor are connected in parallel between the sixth resistor and the ground terminal.

9. The LED dimming driver power supply as described in claim 6, characterized in that: The first voltage divider unit (6) includes a second resistor and a third resistor; the trigger unit (7) is a Zener diode; and the power switch unit (5) includes a second switch transistor, a fourth resistor, a fourth capacitor, a first diode, and a second diode. After the second resistor, the third resistor, and the Zener diode are connected in series, one end of the second resistor is electrically connected to one end of the output terminal of the filter input unit (1), and the other end of the third resistor is electrically connected to the other end of the output terminal of the filter input unit (1). A fourth resistor is connected in series between the control terminal of the second switch and the connection point of the third resistor and the Zener diode. A first diode is connected in parallel between the two ends of the fourth resistor. A fourth capacitor is connected in series between the negative terminal of the first diode and the positive terminal of the Zener diode. The first end of the second switch is electrically connected to the first primary coil of the transformer unit (200) and the absorption clamping unit (15). A second diode is connected in series between the negative terminal of the first diode and the second end of the second switch. The second end of the second switch is electrically connected to the control unit (8).

10. The LED dimming driver power supply as described in claim 4, characterized in that: The zero-crossing detection unit (12) includes a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a fifth diode, and a ninth capacitor. The ninth resistor, the tenth resistor, and the eleventh resistor are connected in series in sequence. One end of the ninth resistor is electrically connected to one end of the second primary coil of the transformer unit (200), and the other end is electrically connected to the control unit (8). The fifth diode, the ninth capacitor, and the twelfth resistor are connected in parallel at the connection point of the tenth resistor and the eleventh resistor. The other end of the second primary coil of the transformer unit (200) is grounded. The voltage regulator unit (13) includes a third diode, a third switch, a fourth diode, a sixth capacitor, a seventh capacitor, an eighth capacitor, and an eighth resistor. The third diode, the eighth resistor, and the fourth diode are connected in series, with one end electrically connected to the connection point of the ninth and tenth resistors, and the other end grounded. The control terminal of the third switch is electrically connected to the connection point of the eighth resistor and the fourth diode. The first end of the third switch is connected in series with the sixth capacitor and then electrically connected to the control unit (8). The sixth capacitor is electrically connected to the positive terminal of the fourth diode. The second end of the third switch is connected in series with the ground terminal, with the eighth capacitor and the seventh capacitor connected in parallel.

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