Ultrahigh frequency gallium nitride LED dimming driving power supply

Abstract

The utility model discloses a driving power supply, belongs to the technical field of LED dimming driving power supplies, and particularly relates to an ultrahigh frequency gallium nitride LED dimming driving power supply which comprises an input circuit, a PFC power factor correction circuit, an LLC half-bridge circuit, an output circuit and an LED. The input end of the PFC power factor correction circuit is connected with the input circuit and inputs working voltage, the output end of the PFC power factor correction circuit is connected with the input end of the LLC half-bridge circuit, and the output end of the LLC half-bridge circuit is connected with the output circuit and outputs voltage to the LED. According to the utility model, the circuit topology is BoostPFC + LLC half-bridge two-stage to obtain high efficiency and low output ripple without stroboflash. The driving power supply has the advantages that constant-voltage output is achieved, a PWM light modulator can be connected between the output and an LED, the light modulation purpose is achieved, the driving power supply can adapt to more light modulators, the light modulation performance is more excellent, and flicker is avoided.

Description

Technical Field

[0001] The utility model discloses a driving power supply, belongs to the technical field of LED dimming driving power supplies, and specifically relates to an ultra-high frequency gallium nitride LED dimming driving power supply. Background Art

[0002] The high efficiency and small size advantages brought by the development of gallium nitride technology are becoming more and more widely used in LED driver power supplies, and are not only used in products with fixed output voltage and current, but also in high-end products such as dimming.

[0003] like Figure 1 and Figure 2 As shown, the gallium nitride LED dimming driving power supply in the prior art has the following problems:

[0004] 1. The LLC control chip power supply and the PFC fast and slow loop power supply are not separated;

[0005] 2. The PFC power supply and the M20 fast and slow loop switching power supply are not separated;

[0006] As a result, the driver cannot respond to the output PWM dimming signal in time, which causes the LED to flicker and cannot achieve constant voltage output. Utility Model Content

[0007] Purpose of the utility model: to provide an ultra-high frequency gallium nitride LED dimming driver power supply to solve the above-mentioned problems.

[0008] Technical solution: An ultra-high frequency gallium nitride LED dimming driver power supply, including: an input circuit, a PFC power factor correction circuit, an LLC half-bridge circuit, an output circuit and an LED;

[0009] The input end of the PFC power factor correction circuit is connected to the input circuit and inputs the working voltage, and the output end is connected to the input end of the LLC half-bridge circuit. The output end of the LLC half-bridge circuit is connected to the output circuit and outputs the voltage to the LED.

[0010] In a further embodiment, a PWM dimmer is connected between the output circuit and the LED to achieve dimming purpose.

[0011] In a further embodiment, a switch tube M20 is provided between the PFC power factor correction circuit and the LLC half-bridge circuit;

[0012] The PFC power factor correction circuit has fast and slow loop control. When the load is light and the dimming duty cycle is low, the switch tube M20 is not turned on, and the PFC power factor correction circuit works in a fast loop state to quickly respond to load changes; when the load is heavy and the dimming duty cycle is high, the switch tube M20 is turned on, and the PFC power factor correction circuit works in a slow loop state.

[0013] In a further embodiment, the PFC power factor correction circuit has an independent power supply with a fast-slow loop switching switch, which is separated from the chip power supply of the LLC half-bridge circuit.

[0014] In a further embodiment, the PFC power factor correction circuit includes: resistor R32, resistor R33, resistor R34, resistor R54, resistor R42, resistor R35, resistor R50, resistor R51, resistor R52, resistor R53, resistor R55, resistor R36, resistor R37, resistor R38, capacitor C20, capacitor C21, capacitor C37, capacitor C23, capacitor C38, capacitor C44, capacitor C22, capacitor C24, capacitor C25, capacitor C31, capacitor C33, capacitor C26, PFC control chip U22, diode D13, diode D20;

[0015] One end of the resistor R32 is input with voltage, and the other end is connected to one end of the resistor R33, the other end of the resistor R33 is connected to one end of the resistor R34, the positive electrode of the diode D20 is connected to the negative electrode of the diode D13 and one end of the capacitor C20, the other end of the capacitor C20 is connected to one end of the capacitor C21, one end of the resistor R54 is connected to the other end of the capacitor C21, and the other end is connected to one end of the resistor R42 for auxiliary signal, the No. 5 pin of the PFC control chip U22 is connected to the other end of the resistor R42 and one end of the capacitor C37, the P Pin 6 of the FC control chip U22 is simultaneously connected to the other end of the capacitor C37, the positive electrode of the diode D13, one end of the capacitor C23, one end of the capacitor C38, one end of the capacitor C44, and one end of the capacitor C31 and is grounded GND. Pin 8 of the PFC control chip U22 is simultaneously connected to the other end of the capacitor C23, the other end of the capacitor C38, the other end of the capacitor C44, the other end of the resistor R34, and the negative electrode of the diode D20. Pin 1 of the PFC control chip U22 is simultaneously connected to one end of the capacitor C24, the other end of the capacitor C31, and the positive electrode of the diode D20. The drain of the switch tube M20 is connected to one end of the resistor R38 and one end of the capacitor C26 at the same time, and the other end of the resistor R37 is connected to the other end of the resistor R38. The other end of the resistor R37 is connected to the other end of the capacitor C26. The drain of the switch tube M20 is connected to the other end of the resistor R38 and one end of the capacitor R26 at the same time. The other end of the resistor R37 is connected to the other end of the capacitor C26. The pin 3 of the PFC control chip U22 is connected to the other end of the capacitor C33 at the same time. One end, one end of the resistor R53, one end of the resistor R55 and one end of the resistor R52 are connected, the other end of the resistor R53 is simultaneously connected to the other end of the point R55 and the other end of the capacitor C33 and is grounded GND, one end of the resistor R50 is input with voltage, and the other end is connected to one end of the resistor R51, the other end of the resistor R51 is connected to the zero end of the resistor R52, pin 4 of the PFC control chip U22 is simultaneously connected to one end of the capacitor C22 and one end of the resistor R35, the other end of the resistor R35 is connected to the light-opening tube, and the other end of the capacitor C22 is grounded.

[0016] In a further embodiment, the LLC half-bridge circuit includes: capacitor C27, resistor R41, diode D21, resistor R39, diode D22, resistor R29, capacitor C40, resistor R23, capacitor C32, resistor R47, resistor R28, diode D43, diode D42, inductor L21-d;

[0017] The gate of the switch tube M20 is simultaneously connected to one end of the capacitor C27, one end of the resistor R41, one end of the resistor R29 and the positive electrode of the diode D21. The other end of the capacitor C27 and the other end of the resistor R41 are grounded GND. One end of the resistor R29 is connected to pin 8 of the PFC control chip U22, and the other end is connected to the negative electrode of the diode D22. The positive electrode of the diode D22 inputs the working voltage. The negative electrode of the diode D21 is simultaneously connected to the other end of the resistor R29, one end of the capacitor C32, and the positive electrode of the diode D22. One end of the resistor R47 is connected to one end of the resistor R28, the other end of the resistor R24 ​​is connected to the other end of the capacitor C32, one end of the inductor L21-d and one end of the capacitor C40 and grounded GND, the cathode of the diode D43 is connected to the other end of the resistor R28, and the anode is connected to the other end of the inductor L21-d and the anode of the diode D42 at the same time, the cathode of the diode D42 is connected to one end of the resistor R23, and the other end of the resistor R23 is connected to the other end of the capacitor C40 and output.

[0018] In a further embodiment, the resistor R28 and the capacitor C32 are used as a filter to adjust the output load condition of the switch tube M20.

[0019] Beneficial effects: The utility model circuit topology is BoostPFC+LLC half-bridge two-stage to achieve high efficiency and low output ripple, no flicker. Constant voltage output, a PWM dimmer can be connected between the output and the LED to achieve the purpose of dimming, so that the driving power supply can adapt to more dimmers, the dimming performance is better, and there will be no flicker. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of a gallium nitride LED dimming drive power supply in the prior art.

[0021] Figure 2 The present invention is a circuit diagram of a gallium nitride LED dimming driving power supply in the prior art.

[0022] Figure 3 This is a schematic diagram of a gallium nitride LED dimming drive power supply of the utility model.

[0023] Figure 4 The utility model discloses a gallium nitride LED dimming driving power supply circuit diagram.

[0024] Figure 5 The gallium nitride LED dimming driving power supply of the present invention is compared with the gallium nitride LED dimming driving power supply in the prior art. DETAILED DESCRIPTION

[0025] The technical solution of the utility model will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0026] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0027] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances. In addition, the technical features involved in the different embodiments of the present utility model described below can be combined with each other as long as they do not conflict with each other.

[0028] An ultra-high frequency gallium nitride LED dimming driving power supply, comprising: an input circuit, a PFC power factor correction circuit, an LLC half-bridge circuit, an output circuit and an LED;

[0029] The input end of the PFC power factor correction circuit is connected to the input circuit and inputs the working voltage, and the output end is connected to the input end of the LLC half-bridge circuit. The output end of the LLC half-bridge circuit is connected to the output circuit and outputs the voltage to the LED.

[0030] In one embodiment, Figures 3 to 5 As shown, a PWM dimmer is connected between the output circuit and the LED to achieve the purpose of dimming.

[0031] In one embodiment, Figures 3 to 5 As shown, a switch tube M20 is provided between the PFC power factor correction circuit and the LLC half-bridge circuit;

[0032] The PFC power factor correction circuit has fast and slow loop control. When the load is light and the dimming duty cycle is low, the switch tube M20 is not turned on, and the PFC power factor correction circuit works in a fast loop state to quickly respond to load changes; when the load is heavy and the dimming duty cycle is high, the switch tube M20 is turned on, and the PFC power factor correction circuit works in a slow loop state.

[0033] In one embodiment, Figures 3 to 5 As shown, the PFC power factor correction circuit has an independent power supply with a fast-slow loop switching switch, which is separated from the chip power supply of the LLC half-bridge circuit.

[0034] In one embodiment, Figures 3 to 5 As shown, the PFC power factor correction circuit includes: resistor R32, resistor R33, resistor R34, resistor R54, resistor R42, resistor R35, resistor R50, resistor R51, resistor R52, resistor R53, resistor R55, resistor R36, resistor R37, resistor R38, capacitor C20, capacitor C21, capacitor C37, capacitor C23, capacitor C38, capacitor C44, capacitor C22, capacitor C24, capacitor C25, capacitor C31, capacitor C33, capacitor C26, PFC control chip U22, diode D13, diode D20;

[0035] One end of the resistor R32 is input with voltage, and the other end is connected to one end of the resistor R33, the other end of the resistor R33 is connected to one end of the resistor R34, the positive electrode of the diode D20 is connected to the negative electrode of the diode D13 and one end of the capacitor C20, the other end of the capacitor C20 is connected to one end of the capacitor C21, one end of the resistor R54 is connected to the other end of the capacitor C21, and the other end is connected to one end of the resistor R42 for auxiliary signal, the No. 5 pin of the PFC control chip U22 is connected to the other end of the resistor R42 and one end of the capacitor C37, the P Pin 6 of the FC control chip U22 is simultaneously connected to the other end of the capacitor C37, the positive electrode of the diode D13, one end of the capacitor C23, one end of the capacitor C38, one end of the capacitor C44, and one end of the capacitor C31 and is grounded GND. Pin 8 of the PFC control chip U22 is simultaneously connected to the other end of the capacitor C23, the other end of the capacitor C38, the other end of the capacitor C44, the other end of the resistor R34, and the negative electrode of the diode D20. Pin 1 of the PFC control chip U22 is simultaneously connected to one end of the capacitor C24, the other end of the capacitor C31, and the positive electrode of the diode D20. The drain of the switch tube M20 is connected to one end of the resistor R38 and one end of the capacitor C26 at the same time, and the other end of the resistor R37 is connected to the other end of the resistor R38. The other end of the resistor R37 is connected to the other end of the capacitor C26. The drain of the switch tube M20 is connected to the other end of the resistor R38 and one end of the capacitor R26 at the same time. The other end of the resistor R37 is connected to the other end of the capacitor C26. The pin 3 of the PFC control chip U22 is connected to the other end of the capacitor C33 at the same time. One end, one end of the resistor R53, one end of the resistor R55 and one end of the resistor R52 are connected, the other end of the resistor R53 is simultaneously connected to the other end of the point R55 and the other end of the capacitor C33 and is grounded GND, one end of the resistor R50 is input with voltage, and the other end is connected to one end of the resistor R51, the other end of the resistor R51 is connected to the zero end of the resistor R52, pin 4 of the PFC control chip U22 is simultaneously connected to one end of the capacitor C22 and one end of the resistor R35, the other end of the resistor R35 is connected to the light-opening tube, and the other end of the capacitor C22 is grounded.

[0036] In one embodiment, Figures 3 to 5As shown, the LLC half-bridge circuit includes: capacitor C27, resistor R41, diode D21, resistor R39, diode D22, resistor R29, capacitor C40, resistor R23, capacitor C32, resistor R47, resistor R28, diode D43, diode D42, inductor L21-d;

[0037] The gate of the switch tube M20 is simultaneously connected to one end of the capacitor C27, one end of the resistor R41, one end of the resistor R29 and the positive electrode of the diode D21. The other end of the capacitor C27 and the other end of the resistor R41 are grounded GND. One end of the resistor R29 is connected to pin 8 of the PFC control chip U22, and the other end is connected to the negative electrode of the diode D22. The positive electrode of the diode D22 inputs the working voltage. The negative electrode of the diode D21 is simultaneously connected to the other end of the resistor R29, one end of the capacitor C32, and the positive electrode of the diode D22. One end of the resistor R47 is connected to one end of the resistor R28, the other end of the resistor R24 ​​is connected to the other end of the capacitor C32, one end of the inductor L21-d and one end of the capacitor C40 and grounded GND, the cathode of the diode D43 is connected to the other end of the resistor R28, and the anode is connected to the other end of the inductor L21-d and the anode of the diode D42 at the same time, the cathode of the diode D42 is connected to one end of the resistor R23, and the other end of the resistor R23 is connected to the other end of the capacitor C40 and output.

[0038] In one embodiment, Figures 3 to 5 As shown, the resistor R28 and the capacitor C32 are used as a filter to adjust the output load condition of the switch tube M20.

[0039] The InnoGaN products INN650D140A and INN650D240A used in the switch tube M20 of the PFC power factor correction circuit and LLC half-bridge circuit both use a compact (DFN8*8) package, which has the characteristics of small parasitic inductance, small parasitic capacitance, low drive charge, and fast switching speed. It not only facilitates the layout and thermal design of the power supply product, but also significantly reduces the switching loss and drive loss of the power supply product.

[0040] Working principle: The PFC power factor correction circuit of the utility model has a fast and slow loop control. When the load is light and the dimming duty cycle is low, the switch tube M20 is not turned on, and the PFC power factor correction circuit works in a fast loop state to quickly respond to load changes. When the load is heavy and the dimming duty cycle is high, the switch tube M20 is turned on, and the PFC power factor correction circuit works in a slow loop state to obtain a good power factor and low harmonic THD.

[0041] The PFC power factor correction circuit has a fast and slow loop switching time and speed that can be adjusted. The PFC power factor correction circuit has a fast and slow loop switching switch that is powered independently and separated from the LLC chip power supply to avoid interference.

[0042] After the power supply of the fast and slow loop switching switch of the PFC power factor correction circuit is independent, the filter resistor R28 and capacitor C32 can be introduced to prevent the switch tube M20 from turning on at a low duty cycle of PWM dimming, such as 1%, but delay the turn-on to about 10%. At this time, the driving power supply is already working in a higher power state, and the output capacitor of the PFC power factor correction circuit has stored enough energy and will not be pulled to a very low state by the output load change, thereby maintaining the normal load of the LLC half-bridge circuit and avoiding flickering.

[0043] If the PFC power factor correction circuit switches between the fast and slow loops when the duty cycle is 1%, from the fast loop to the slow loop, the PFC power factor correction circuit cannot respond quickly to large changes in the output load in the slow loop state, and is thus pulled to a very low state, unable to maintain the normal load of the LLC half-bridge circuit, causing the LED to flicker.

[0044] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention of the utility model.

Claims

1. An ultra-high frequency gallium nitride LED dimming driver, characterized in that: The LED dimming driving power supply comprises: an input circuit, a PFC power factor correction circuit, an LLC half-bridge circuit, an output circuit and an LED; The input end of the PFC power factor correction circuit is connected to the input circuit and inputs the working voltage, and the output end is connected to the input end of the LLC half-bridge circuit. The output end of the LLC half-bridge circuit is connected to the output circuit and outputs the voltage to the LED.

2. According to claim 1, an ultra-high frequency gallium nitride LED dimming driver power supply, characterized in that: A PWM dimmer is connected between the output circuit and the LED to achieve the purpose of dimming.

3. The ultra-high frequency gallium nitride LED dimming driver according to claim 1, characterized in that: A switch tube M20 is provided between the PFC power factor correction circuit and the LLC half-bridge circuit; The PFC power factor correction circuit has fast and slow loop control. When the load is light and the dimming duty cycle is low, the switch tube M20 is not turned on, and the PFC power factor correction circuit works in a fast loop state to quickly respond to load changes; when the load is heavy and the dimming duty cycle is high, the switch tube M20 is turned on, and the PFC power factor correction circuit works in a slow loop state.

4. The ultra-high frequency gallium nitride LED dimming driver according to claim 1, characterized in that: The PFC power factor correction circuit has an independent power supply with a fast-slow loop switching switch, which is separated from the chip power supply of the LLC half-bridge circuit.

5. The ultra-high frequency gallium nitride LED dimming driver according to claim 3, characterized in that: The PFC power factor correction circuit includes: a resistor R32, a resistor R33, a resistor R34, a resistor R54, a resistor R42, a resistor R35, a resistor R50, a resistor R51, a resistor R52, a resistor R53, a resistor R55, a resistor R36, a resistor R37, a resistor R38, a capacitor C20, a capacitor C21, a capacitor C37, a capacitor C23, a capacitor C38, a capacitor C44, a capacitor C22, a capacitor C24, a capacitor C25, a capacitor C31, a capacitor C33, a capacitor C26, a PFC control chip U22, a diode D13, and a diode D20; One end of the resistor R32 is input with voltage, and the other end is connected to one end of the resistor R33, the other end of the resistor R33 is connected to one end of the resistor R34, the positive electrode of the diode D20 is connected to the negative electrode of the diode D13 and one end of the capacitor C20, the other end of the capacitor C20 is connected to one end of the capacitor C21, one end of the resistor R54 is connected to the other end of the capacitor C21, and the other end is connected to one end of the resistor R42 for auxiliary signal, the No. 5 pin of the PFC control chip U22 is connected to the other end of the resistor R42 and one end of the capacitor C37, the P Pin 6 of the FC control chip U22 is simultaneously connected to the other end of the capacitor C37, the positive electrode of the diode D13, one end of the capacitor C23, one end of the capacitor C38, one end of the capacitor C44, and one end of the capacitor C31 and is grounded GND. Pin 8 of the PFC control chip U22 is simultaneously connected to the other end of the capacitor C23, the other end of the capacitor C38, the other end of the capacitor C44, the other end of the resistor R34, and the negative electrode of the diode D20. Pin 1 of the PFC control chip U22 is simultaneously connected to one end of the capacitor C24, the other end of the capacitor C31, and the positive electrode of the diode D20. The drain of the switch tube M20 is connected to one end of the resistor R38 and one end of the capacitor C26 at the same time, one end of the resistor R37 and one end of the capacitor C24 at the same time, one end of the resistor R36 and one end of the resistor R37 at the same time, and the drain of the switch tube M20 is connected to the other end of the resistor R38 and one end of the capacitor R26 at the same time. The other end of the resistor R37 is connected to the other end of the capacitor C26, and the pin 3 of the PFC control chip U22 is connected to one end of the capacitor C33 at the same time. The first end of the PFC control chip U22 is connected to one end of the capacitor C22 and one end of the resistor R35. The other end of the resistor R53 is connected to the other end of the resistor R55 and the other end of the capacitor C33 and is grounded GND. One end of the resistor R50 is input with voltage, and the other end is connected to one end of the resistor R51. The other end of the resistor R51 is connected to the zero end of the resistor R52. Pin 4 of the PFC control chip U22 is connected to one end of the capacitor C22 and one end of the resistor R35. The other end of the resistor R35 is connected to the open tube, and the other end of the capacitor C22 is grounded.

6. The ultra-high frequency gallium nitride LED dimming driver according to claim 5, characterized in that: The LLC half-bridge circuit includes: capacitor C27, resistor R41, diode D21, resistor R39, diode D22, resistor R29, capacitor C40, resistor R23, capacitor C32, resistor R47, resistor R28, diode D43, diode D42, inductor L21-d; The gate of the switch tube M20 is simultaneously connected to one end of the capacitor C27, one end of the resistor R41, one end of the resistor R29 and the positive electrode of the diode D21. The other end of the capacitor C27 and the other end of the resistor R41 are grounded GND. One end of the resistor R29 is connected to pin 8 of the PFC control chip U22, and the other end is connected to the negative electrode of the diode D22. The positive electrode of the diode D22 inputs the working voltage. The negative electrode of the diode D21 is simultaneously connected to the other end of the resistor R29, one end of the capacitor C32, and the positive electrode of the diode D22. One end of the resistor R47 is connected to one end of the resistor R28, the other end of the resistor R24 ​​is connected to the other end of the capacitor C32, one end of the inductor L21-d and one end of the capacitor C40 and grounded GND, the cathode of the diode D43 is connected to the other end of the resistor R28, and the anode is connected to the other end of the inductor L21-d and the anode of the diode D42 at the same time, the cathode of the diode D42 is connected to one end of the resistor R23, and the other end of the resistor R23 is connected to the other end of the capacitor C40 and output.

7. The ultra-high frequency gallium nitride LED dimming driving power supply according to claim 6, characterized in that: The resistor R28 and the capacitor C32 are used as a filter to adjust the output load condition of the switch tube M20.

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