LED brushless direct current motor fan lamp power supply control circuit

Abstract

The invention discloses an LED brushless direct current motor fan lamp power supply control circuit, and relates to the technical field of fan lamp control, in the circuit, a remote control and motor control circuit is respectively connected with a brushless direct current motor, an intelligent signal sensor, a switch rectification circuit, a DC / DC constant voltage circuit and an LED light source linear constant current driving chip; the intelligent signal sensor is connected with the remote controller; the DC / DC constant voltage circuit is also connected with the switch rectification circuit. And the DC / DC constant-voltage circuit is also in negative feedback connection with the LED light source linear constant-current driving chip. According to the LED brushless direct current motor fan lamp power supply control circuit, the number of elements adopted during LED brushless direct current motor fan lamp power supply control can be reduced by arranging the LED light source linear constant current driving chip, so that the LED brushless direct current motor fan lamp power supply control circuit has the advantages of being high in integration level, low in cost and small in size.

Description

Technical Field

[0001] The present application relates to the technical field of fan light control, and particularly to a power control circuit for an LED brushless DC motor fan light. Background Art

[0002] Fan lights became popular in Europe and America at the end of the 20th century, and AC motors were used at that time. The previously popular LED BLDC fan lights were mainly ceiling fan lights, which were large in size, heavy (over 5 kg), had high logistics costs, and required professional personnel for installation, so the cost was high and the selling price was also high.

[0003] In order to enable low-income people around the world to afford LED BLDC fan lights, a current low-cost and high-performance LED BLDC bulb fan light has emerged: high performance, using a small-size brushless three-phase DC motor, and the motor power is generally slightly smaller than that of ordinary LED BLDC ceiling fan lights; small packaging volume, less than one-tenth of the packaging volume of ordinary LED BLDC ceiling fan lights; the weight does not exceed 0.5 kg, less than one-tenth of the weight of ordinary LED ceiling fan lights; low logistics costs, only one-tenth of the logistics costs of ordinary LED ceiling fan lights; using an E27 / E26 screw lamp holder, no professional personnel are required for installation, and there is no installation cost. In order to reduce costs, the LED BLDC bulb fan light has made innovations in many aspects: developing a dedicated small-size BLDC motor; detachable fan blades for convenient packaging; the overall structure is quite compact, and basically all structures are made of plastic materials. However, only the power controller of the bulb fan light has not been innovated and still uses the same power controller as ordinary LED BLDC ceiling fan lights, which has become an obstacle to further reducing the cost of LED BLDC bulb fan lights. Summary of the Invention

[0004] The purpose of the present application is to provide a power control circuit for an LED brushless DC motor fan light, which can reduce the number of components used in the power control of the LED brushless DC motor fan light, and make the power control of the LED brushless DC motor fan light have the advantages of high integration, low cost, and small volume.

[0005] To achieve the above purpose, the present application provides the following solutions:

[0006] The present application provides a power control circuit for an LED brushless DC motor fan light, including:

[0007] A switch rectification circuit, a DC / DC constant voltage circuit, a remote control and motor control circuit, and an LED light source linear constant current drive chip;

[0008] The remote control and motor control circuits are respectively connected to the brushless DC motor, the intelligent signal sensor, the switching rectifier circuit, the DC / DC constant voltage circuit, and the LED light source linear constant current drive chip;

[0009] The DC / DC constant voltage circuit is also connected to the switching rectifier circuit; the DC / DC constant voltage circuit is also connected to the LED light source linear constant current drive chip through the third LED light source and the fourth LED light source; the DC / DC constant voltage circuit is connected to the LED light source linear constant current drive chip in negative feedback.

[0010] Optionally, the switching rectifier circuit includes:

[0011] A switch, a rectifier bridge, a first resistor, a second resistor, a third resistor, a fourth resistor, and a third voltage regulator tube;

[0012] The first end of the switch is connected to the first output end of the AC power supply;

[0013] The second end of the switch is connected to the first end of the rectifier bridge;

[0014] The second end of the rectifier bridge is connected to the first end of the DC / DC constant voltage circuit;

[0015] The third end of the rectifier bridge and the first end of the first resistor are both connected to the second output end of the AC power supply;

[0016] The fourth end of the rectifier bridge, the first end of the second resistor, the positive pole of the third voltage regulator tube, the first end of the third resistor, and the first end of the fourth resistor are all grounded to the first end of the LED light source linear constant current drive chip;

[0017] The second end of the third resistor is connected to the second end of the LED light source linear constant current drive chip;

[0018] The second end of the fourth resistor is connected to the third end of the LED light source linear constant current drive chip;

[0019] The second end of the first resistor, the second end of the second resistor, and the negative pole of the third voltage regulator tube are all connected to the first end of the remote control and motor control circuit.

[0020] Optionally, the DC / DC constant voltage circuit includes:

[0021] A transformer, a fourth diode, a fifth resistor, a sixth resistor, a seventh resistor, a first capacitor, and a second capacitor;

[0022] The primary coil of the transformer serves as the first end of the DC / DC constant voltage circuit;

[0023] The first end of the secondary coil of the transformer is respectively connected to the positive electrode of the fourth diode and the first end of the fifth resistor;

[0024] The negative electrode of the fourth diode and the first end of the first capacitor are connected as the second end of the DC / DC constant voltage circuit, and are respectively connected to the second end of the remote control and motor control circuit, the fourth end of the LED light source linear constant current drive chip, the positive electrode of the third LED light source, and the positive electrode of the fourth LED light source;

[0025] The negative electrode of the third LED light source is connected to the fifth end of the LED light source linear constant current drive chip;

[0026] The negative electrode of the fourth LED light source is connected to the sixth end of the LED light source linear constant current drive chip;

[0027] The second end of the fifth resistor is connected to the first end of the sixth resistor as the third end of the DC / DC constant voltage circuit;

[0028] The second end of the sixth resistor, the first end of the seventh resistor, and the first end of the second capacitor are connected as the fourth end of the DC / DC constant voltage circuit and are connected to the seventh end of the LED light source linear constant current drive chip;

[0029] The second end of the secondary coil of the transformer, the second end of the seventh resistor, the second end of the first capacitor, and the second end of the second capacitor are all grounded.

[0030] Optionally, the LED light source linear constant current drive chip includes:

[0031] A first linear constant current circuit, a second linear constant current circuit, and a feedback circuit;

[0032] Both the first linear constant current circuit and the second linear constant current circuit are connected to the feedback circuit;

[0033] The first linear constant current circuit is also respectively connected to the first dimming signal output end of the remote control and motor control circuit and the negative electrode of the third LED light source;

[0034] The second linear constant current circuit is also respectively connected to the second dimming signal output end of the remote control and motor control circuit and the negative electrode of the fourth LED light source;

[0035] The feedback circuit is also connected to the fourth end of the DC / DC constant voltage circuit.

[0036] Optionally, the first linear constant current circuit includes:

[0037] A first multiplier, a first error amplifier, and a first MOS power switch tube;

[0038] The input terminal of the first multiplier is connected to the first dimming signal output terminal of the remote control and motor control circuit;

[0039] The output terminal of the first multiplier is connected to the positive input terminal of the first error amplifier;

[0040] The negative input terminal of the first error amplifier is respectively connected to the source electrode of the first MOS power switch tube and the second terminal of the third resistor;

[0041] The output terminal of the first error amplifier is connected to the gate electrode of the first MOS power switch tube;

[0042] The drain electrode of the first MOS power switch tube is connected to the negative electrode of the third LED light source and the feedback circuit.

[0043] Optionally, the second linear constant current circuit includes:

[0044] A second multiplier, a second error amplifier, and a second MOS power switch tube;

[0045] The input terminal of the second multiplier is connected to the second dimming signal output terminal of the remote control and motor control circuit;

[0046] The output terminal of the second multiplier is connected to the positive input terminal of the second error amplifier;

[0047] The negative input terminal of the second error amplifier is respectively connected to the source electrode of the second MOS power switch tube and the second terminal of the fourth resistor;

[0048] The output terminal of the second error amplifier is connected to the gate electrode of the second MOS power switch tube;

[0049] The drain electrode of the second MOS power switch tube is connected to the negative electrode of the fourth LED light source and the feedback circuit.

[0050] Optionally, the feedback circuit includes:

[0051] A first comparator, a first field effect transistor, a second field effect transistor, a first NOT logic gate, and a first controlled current source;

[0052] The positive input terminal of the first comparator is respectively connected to the drain electrode of the first MOS power switch tube, the negative electrode of the third LED light source, and the drain electrode of the second field effect transistor;

[0053] The negative input terminal of the first comparator is respectively connected to the drain electrode of the second MOS power switch tube, the negative electrode of the fourth LED light source, and the drain electrode of the first field effect transistor;

[0054] The source electrode of the first field effect transistor and the source electrode of the second field effect transistor are connected to the input terminal of the first controlled current source;

[0055] The output terminal of the first comparator is respectively connected to the input terminal of the first non-logic device and the gate electrode of the first field effect transistor;

[0056] The output terminal of the first non-logic device is connected to the gate electrode of the second field effect transistor.

[0057] Optionally, the first linear constant current circuit includes:

[0058] A first multiplier, a first error amplifier, and a first MOS power switch transistor;

[0059] The input terminal of the first multiplier is connected to the first dimming signal output terminal of the remote control and motor control circuit;

[0060] The output terminal of the first multiplier is connected to the positive input terminal of the first error amplifier;

[0061] The negative input terminal of the first error amplifier is respectively connected to the source electrode of the first MOS power switch transistor and the second terminal of the third resistor;

[0062] The output terminal of the first error amplifier is connected to the gate electrode of the first MOS power switch transistor;

[0063] The drain electrode of the first MOS power switch transistor is connected to the negative electrode of the third LED light source;

[0064] The gate electrode of the first MOS power switch transistor is connected to the feedback circuit.

[0065] Optionally, the second linear constant current circuit includes:

[0066] A second multiplier, a second error amplifier, and a second MOS power switch transistor;

[0067] The input terminal of the second multiplier is connected to the second dimming signal output terminal of the remote control and motor control circuit;

[0068] The output terminal of the second multiplier is connected to the positive input terminal of the second error amplifier;

[0069] The negative input terminal of the second error amplifier is respectively connected to the source electrode of the second MOS power switch transistor and the second terminal of the fourth resistor;

[0070] The output terminal of the second error amplifier is connected to the gate electrode of the second MOS power switch transistor;

[0071] The drain of the second MOS power switch is connected to the negative electrode of the third LED light source;

[0072] The gate of the second MOS power switch is connected to the feedback circuit.

[0073] Optionally, the feedback circuit includes:

[0074] A second comparator, a first field-effect transistor, a second field-effect transistor, a first NOT logic gate, and a second controlled current source;

[0075] The negative input terminal of the second comparator is respectively connected to the gate of the first MOS power switch, the negative electrode of the third LED light source, and the drain of the second field-effect transistor;

[0076] The positive input terminal of the second comparator is respectively connected to the gate of the second MOS power switch, the negative electrode of the fourth LED light source, and the drain of the first field-effect transistor;

[0077] The source of the first field-effect transistor and the source of the second field-effect transistor are connected to the input terminal of the second controlled current source;

[0078] The output terminal of the second comparator is respectively connected to the input terminal of the first NOT logic gate and the gate of the first field-effect transistor;

[0079] The output terminal of the first NOT logic gate is connected to the gate of the second field-effect transistor.

[0080] According to the specific embodiments provided by the present application, the following technical effects are disclosed in the present application:

[0081] The present application provides a power control circuit for an LED brushless DC motor fan light, which is applicable to low-cost LED BLDC bulb fan lights. A chip with two built-in linear constant current circuits and a feedback circuit is used to replace the two-way light source switch constant current drive circuit, saving two power inductors and their supporting high-voltage components. There is a negative feedback control connection between the new LED light source linear constant current drive chip and the constant voltage circuit, and the two work together to ensure that the energy conversion efficiency of the light source system is at an acceptable high level. Combining the large loop feedback control technology and the two-way linear constant current integrated circuit (chip) with a feedback circuit, compared with the traditional LED BLDC fan light power controller, the main core performance (such as efficiency) is comparable, but there are the following advantages: low component cost: two power inductors, two high-voltage freewheeling diodes, two high-voltage output capacitors, etc., a total of 18 components are saved; the total number of components of the new power control circuit is reduced by at least 13, accounting for one-third of the total number of components; the power supply volume is reduced by at least one-third, and the power supply PCB area is reduced by at least one-third, suitable for compact miniaturized application scenarios; low electromagnetic radiation and low cost of anti-radiation components, suitable for places with high electromagnetic environment requirements. The processing and testing costs are low, and this technology is also applicable to ordinary intelligent lighting application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0082] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0083] Figure 1 It is the schematic diagram of the power control circuit of the existing LED BLDC fan light in an embodiment of the present application;

[0084] Figure 2 It is the internal circuit of the DC / DC constant voltage circuit 110 in an embodiment of the present application;

[0085] Figure 3 It is the schematic diagram of the drive circuit of the two-way LED light source in an embodiment of the present application;

[0086] Figure 4 It is the improved schematic diagram of the power control circuit of the existing LED BLDC fan light in an embodiment of the present application;

[0087] Figure 5 It is the schematic diagram of the internal error amplifier in an embodiment of the present application;

[0088] Figure 6 It is the implementation schematic diagram of the power control circuit for automatically matching the LED BLDC fan light in an embodiment of the present application;

[0089] Figure 7 Internal detailed schematic diagram of the connection between the negative feedback circuit 341 and the constant voltage circuit 310 in an embodiment of the present application;

[0090] Figure 8 Schematic diagram of the automatic matching circuit when the power tube operates in the linear region in an embodiment of the present application;

[0091] Figure 9 Internal detailed schematic of the connection between the negative feedback circuit 441 and the constant voltage circuit 310 in an embodiment of the present application;

[0092] Figure 10 Simplified diagram of the (improved) DC / DC constant voltage circuit in an embodiment of the present application;

[0093] Figure 11 Schematic diagram of the currently mature intelligent lighting circuit in an embodiment of the present application;

[0094] Figure 12 Improved schematic diagram of the intelligent lighting circuit in an embodiment of the present application.

[0095] Reference numerals: (Before improvement) DC / DC constant voltage circuit 110; remote control and motor control circuit 120; intelligent signal sensor 130; first switch constant current drive circuit 140; second switch constant current drive circuit 150; switch 101; rectifier bridge 102; first resistor 103; second resistor 104; third voltage regulator diode 105; brushless DC motor 106; first LED light source 107; second LED light source 108; DC / DC constant voltage control chip 111; power tube 112; eighth resistor 113; transformer 114; sixth resistor 115; fifth resistor 116; fourth diode 117; first capacitor 118; (After improvement) DC / DC constant voltage circuit 310; seventh resistor 311; second capacitor 312; ninth resistor 141; third capacitor 142; LED dimming constant current chip 143; tenth resistor 144; eleventh resistor 145; inductor 146; seventh diode 147; fourth capacitor 148; twelfth resistor 149; third LED light source 201; fourth LED light source 202; third resistor 203, fourth resistor 204; dual - path linear constant current circuit 241; first MOS power switch tube 242; second MOS power switch tube 243; first multiplier 245, first error amplifier 246; first initial LED light source linear constant current drive chip 340; negative feedback circuit 310; negative feedback circuit 341; first comparator 342; remote control circuit 220; second comparator 442; first field - effect tube 343; second field - effect tube 345; first NOT gate 344; first controlled current source 346; LED light source linear constant current drive chip 440; feedback circuit 441; second controlled current source 446. Detailed Implementation Modes

[0096] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0097] To make the above objects, features, and advantages of the present application more obvious and understandable, the present application will be further described in detail below in conjunction with the accompanying drawings and specific implementation modes.

[0098] In an exemplary embodiment, as Figure 8 shown, a power control circuit for an LED brushless DC motor fan light is provided, including:

[0099] a switching rectifier circuit, an improved DC / DC constant voltage circuit 310, a remote control and motor control circuit 120, and an LED light source linear constant current driving chip 440.

[0100] The remote control and motor control circuit 120 is respectively connected to a brushless DC motor 106, an intelligent signal sensor 130, the switching rectifier circuit, the DC / DC constant voltage circuit 310, and the LED light source linear constant current driving chip. The intelligent signal sensor is connected to the remote control.

[0101] The DC / DC constant voltage circuit 310 is also connected to the switching rectifier circuit. The DC / DC constant voltage circuit 310 is also connected to the LED light source linear constant current driving chip through a third LED light source 201 and a fourth LED light source 202. The DC / DC constant voltage circuit is connected to the LED light source linear constant current driving chip in a negative feedback manner.

[0102] The switching rectifier circuit includes:

[0103] a switch 101, a rectifier bridge 102, a first resistor 103, a second resistor 104, a third resistor 203, a fourth resistor 204, and a third voltage regulator tube 105.

[0104] The first end of the switch is connected to the first output end of the AC power supply.

[0105] The second end of the switch is connected to the first end of the rectifier bridge.

[0106] The second end of the rectifier bridge is connected to the first end of the DC / DC constant voltage circuit 310.

[0107] The third end of the rectifier bridge and the first end of the first resistor are both connected to the second output end of the AC power supply.

[0108] The fourth terminal of the rectifier bridge, the first terminal of the second resistor, the positive electrode of the third voltage regulator diode, the first terminal of the third resistor, and the first terminal of the fourth resistor are all grounded to the first terminal of the LED light source linear constant current driving chip.

[0109] The second terminal of the third resistor is connected to the second terminal of the LED light source linear constant current driving chip.

[0110] The second terminal of the fourth resistor is connected to the third terminal of the LED light source linear constant current driving chip.

[0111] The second terminal of the first resistor, the second terminal of the second resistor, and the negative electrode of the third voltage regulator diode are all connected to the first terminal of the remote control and motor control circuit 120.

[0112] The DC / DC constant voltage circuit 310 includes:

[0113] Transformer 114, fourth diode 117, fifth resistor 116, sixth resistor 115, seventh resistor 311, first capacitor 118, second capacitor 312.

[0114] The primary coil of the transformer serves as the first terminal of the DC / DC constant voltage circuit 310.

[0115] The first terminal of the secondary coil of the transformer is respectively connected to the positive electrode of the fourth diode and the first terminal of the fifth resistor.

[0116] The negative electrode of the fourth diode and the first terminal of the first capacitor are connected as the second terminal of the DC / DC constant voltage circuit 310, and are respectively connected to the second terminal of the remote control and motor control circuit, the fourth terminal of the LED light source linear constant current driving chip, the positive electrode of the third LED light source, and the positive electrode of the fourth LED light source.

[0117] The negative electrode of the third LED light source is connected to the fifth terminal of the LED light source linear constant current driving chip.

[0118] The negative electrode of the fourth LED light source is connected to the sixth terminal of the LED light source linear constant current driving chip.

[0119] The second terminal of the fifth resistor is connected to the first terminal of the sixth resistor, serving as the third terminal of the DC / DC constant voltage circuit 310.

[0120] The second terminal of the sixth resistor, the first terminal of the seventh resistor, and the first terminal of the second capacitor are connected as the fourth terminal of the DC / DC constant voltage circuit 310, and are connected to the seventh terminal of the LED light source linear constant current driving chip.

[0121] The second terminal of the secondary coil of the transformer, the second terminal of the seventh resistor, the second terminal of the first capacitor, and the second terminal of the second capacitor are all grounded.

[0122] The remote control and motor control circuit 120 is used to generate a first modulation signal and a second modulation signal.

[0123] The LED light source linear constant current drive chip includes:

[0124] A dual - path linear constant current circuit 241 (a first linear constant current circuit, a second linear constant current circuit) and a feedback circuit 441.

[0125] Both the first linear constant current circuit and the second linear constant current circuit are connected to the feedback circuit.

[0126] The first linear constant current circuit is also respectively connected to the first modulation signal output terminal of the remote control and motor control circuit and the negative electrode of the third LED light source.

[0127] The second linear constant current circuit is also respectively connected to the second modulation signal output terminal of the remote control and motor control circuit and the negative electrode of the fourth LED light source.

[0128] The feedback circuit is also connected to the fourth terminal of the DC / DC constant voltage circuit 310.

[0129] The first linear constant current circuit includes:

[0130] A first multiplier 245, a first error amplifier 246, and a first MOS power switch tube 242.

[0131] The input terminal of the first multiplier is connected to the first modulation signal output terminal of the remote control and motor control circuit.

[0132] The output terminal of the first multiplier is connected to the positive input terminal of the first error amplifier.

[0133] The negative input terminal of the first error amplifier is respectively connected to the source electrode of the first MOS power switch tube and the second terminal of the third resistor.

[0134] The output terminal of the first error amplifier is connected to the gate electrode of the first MOS power switch tube.

[0135] The drain electrode of the first MOS power switch tube is connected to the negative electrode of the third LED light source and the feedback circuit.

[0136] The second linear constant current circuit includes:

[0137] A second multiplier, a second error amplifier, and a second MOS power switch tube 243.

[0138] The input terminal of the second multiplier is connected to the second modulation signal output terminal of the remote control and motor control circuit.

[0139] The output terminal of the second multiplier is connected to the positive input terminal of the second error amplifier.

[0140] The negative input terminal of the second error amplifier is respectively connected to the source electrode of the second MOS power switch tube and the second terminal of the fourth resistor.

[0141] The output terminal of the second error amplifier is connected to the gate electrode of the second MOS power switch tube.

[0142] The drain electrode of the second MOS power switch tube is connected to the negative electrode of the fourth LED light source and the feedback circuit.

[0143] The feedback circuit includes:

[0144] A first comparator, a first field effect transistor, a second field effect transistor, a first non-logic gate, and a first controlled current source.

[0145] Optionally, the positive input terminal of the first comparator is respectively connected to the drain electrode of the optionally first MOS power switch tube, the negative electrode of the optionally third LED light source, and the drain electrode of the optionally second field effect transistor.

[0146] Optionally, the negative input terminal of the first comparator is respectively connected to the drain electrode of the optionally second MOS power switch tube, the negative electrode of the optionally fourth LED light source, and the drain electrode of the optionally first field effect transistor.

[0147] Optionally, the source electrode of the first field effect transistor and the source electrode of the optionally second field effect transistor are connected to the input terminal of the optionally first controlled current source.

[0148] Optionally, the output terminal of the first comparator is respectively connected to the input terminal of the optionally first non-logic gate and the gate electrode of the optionally first field effect transistor.

[0149] Optionally, the output terminal of the first non-logic gate is connected to the gate electrode of the optionally second field effect transistor.

[0150] As another implementation manner, the first linear constant current circuit includes:

[0151] A first multiplier, a first error amplifier, and a first MOS power switch tube.

[0152] The input terminal of the first multiplier is connected to the first dimming signal output terminal of the remote control and motor control circuit.

[0153] The output terminal of the first multiplier is connected to the positive input terminal of the first error amplifier.

[0154] The negative input terminal of the first error amplifier is respectively connected to the source electrode of the first MOS power switch tube and the second terminal of the third resistor.

[0155] The output terminal of the first error amplifier is connected to the gate electrode of the first MOS power switch tube.

[0156] The drain electrode of the first MOS power switch tube is connected to the negative electrode of the third LED light source.

[0157] The gate of the first MOS power switch is connected to the feedback circuit.

[0158] The second linear constant current circuit includes:

[0159] A second multiplier, a second error amplifier, and a second MOS power switch.

[0160] The input terminal of the second multiplier is connected to the second dimming signal output terminal of the remote control and motor control circuit.

[0161] The output terminal of the second multiplier is connected to the positive input terminal of the second error amplifier.

[0162] The negative input terminal of the second error amplifier is respectively connected to the source of the second MOS power switch and the second terminal of the fourth resistor.

[0163] The output terminal of the second error amplifier is connected to the gate of the second MOS power switch.

[0164] The drain of the second MOS power switch is connected to the negative electrode of the fourth LED light source.

[0165] The gate of the second MOS power switch is connected to the feedback circuit.

[0166] Both the first MOS power switch and the second MOS power switch are NMOS power switches.

[0167] The feedback circuit includes:

[0168] A second comparator, a first field effect transistor, a second field effect transistor, a first NOT logic gate, and a second controlled current source.

[0169] The negative input terminal of the second comparator is respectively connected to the gate of the optionally first MOS power switch, the negative electrode of the optionally third LED light source, and the drain of the optionally second field effect transistor.

[0170] The positive input terminal of the second comparator is respectively connected to the gate of the optionally second MOS power switch, the negative electrode of the optionally fourth LED light source, and the drain of the optionally first field effect transistor.

[0171] The source of the first field effect transistor and the source of the optionally second field effect transistor are connected to the input terminal of the optionally second controlled current source.

[0172] The output terminal of the second comparator is respectively connected to the input terminal of the optionally first NOT logic gate and the gate of the optionally first field effect transistor.

[0173] The output terminal of the NOT logic gate is connected to the gate of the optionally second field effect transistor.

[0174] In this embodiment, the improvement process of the power control circuit of the LED brushless DC motor fan light is as follows Figures 1 - 12 , Figures 1 - 12 In the figure, the reference numerals are as follows: (before improvement) DC / DC constant voltage circuit 110; remote control and motor control circuit 120; intelligent signal sensor 130; first switch constant current drive circuit 140; second switch constant current drive circuit 150; switch 101; rectifier bridge 102; first resistor 103; second resistor 104; third voltage regulator diode 105; brushless DC motor 106; fifth LED light source 107; sixth LED light source 108; DC / DC constant voltage control chip 111; power transistor 112; eighth resistor 113; transformer 114; sixth resistor 115; fifth resistor 116; fourth diode 117; first capacitor 118; (after improvement) DC / DC constant voltage circuit 310; seventh resistor 311; second capacitor 312; ninth resistor 141; third capacitor 142; LED dimming constant current chip 143; tenth resistor 144; eleventh resistor 145; inductor 146; seventh diode 147; fourth capacitor 148; twelfth resistor 149; third LED light source 201; fourth LED light source 202; third resistor 203, fourth resistor 204; dual-line linear constant current circuit 241; first MOS power switch transistor 242; second MOS power switch transistor 243; first multiplier 245, first error amplifier 246; first initial LED light source linear constant current drive chip 340; negative feedback circuit 310; negative feedback circuit 341; first comparator 342; remote control circuit 220; second comparator 442; first field effect transistor 343; second field effect transistor 345; non-logic device 344; first controlled current source 346; LED light source linear constant current drive chip 440; feedback circuit 441; second controlled current source 446.

[0175] Figure 1This is the schematic diagram of the power control circuit adopted by almost all current LED BLDC fan lights (including ceiling fan lights and the newly emerging low-cost bulb fan lights). 107 and 108 are two LED light sources with different color temperatures. One is warm light with a color temperature of approximately 3000K, and the other is cold light with a color temperature of around 6000K. Through the remote control, the ratio of the light fluxes output by the two light sources can be adjusted steplessly, thereby achieving stepless adjustment of the overall lamp color temperature, with a minimum of 3000K and a maximum of 6000K. The brushless DC motor BLDC106 requires a relatively complex drive circuit 120, which is generally implemented through a dedicated 32-bit high-speed MCU for driving and control. The fan light requires precise control of light brightness and color temperature, and there are also multiple speed gears for the motor, up to 7 wind speed gears. Therefore, all LED BLDC fan lights are standardly equipped with a remote control, and there are various remote control methods: network control; voice control; mobile APP remote control; 2.4G remote control; Bluetooth remote control; infrared remote control, etc. The intelligent signal receiving sensor 130 is responsible for receiving the intelligent remote control signal, performing preliminary shaping processing, and then sending it to the subsequent MCU for decoding. Low-cost bulb LED BLDC fan lights generally adopt the lowest-cost infrared remote control technology. Since the BLDC drive motor MCU is a high-speed 32-bit MCU, it is generally also used as the infrared remote control signal decoding MCU, as well as for generating the light source dimming and color temperature control signals. So Figure 1 the remote control and motor control circuit 120 in

[0176] is the control core of the entire circuit. Figure 1 For a so-called DC motor, a stable DC power supply is required, that is, Figure 2 the constant voltage output CV provided by the DC / DC constant voltage circuit 110 in Figure 3It is the schematic diagram of the driving circuit for two light sources. Each light source requires such an independent switched constant current power supply, which has an independent power inductor 146 and an independent inductor freewheeling diode 147. The respective power switching transistors are generally integrated inside the constant current chip 143. The function of the rectifier bridge 102 is to rectify the 50Hz / 60Hz alternating current into pulsating direct current for use by the subsequent circuits. The functions of resistor 103, resistor 104, and the 5V zener diode 105 are to detect the switching state of the wall switch 101. If the switch 101 is closed, the remote control and motor control circuit 120 will receive a 5V pulse signal with a frequency of 50Hz / 60Hz and a duty cycle of 50%; if the switch 101 is in the open state, the remote control and motor control circuit 120 will receive a zero-level signal. In this way, the remote control and motor control circuit 120 can identify the user's control intention for the switch 101, and thus make different control methods for the light source or the motor.

[0177] The currently relatively mature power controller structure of the LED BLDC ceiling fan light. The entire system includes three independent switched-mode power supplies, with three independent power inductors, three independent power switches, and three independent rectifying power diodes. The three switched-mode power supplies are not subordinate to each other and do not cooperate with each other. This results in a relatively high electromagnetic space / conduction radiation level of the entire system, and a relatively large cost needs to be paid to pass the electromagnetic radiation certification. For the low-cost LED BLDC bulb ceiling fan light, the cost of this power controller accounts for a relatively high proportion in the total cost. The power controller has a relatively large volume, presenting a great challenge in miniaturized applications. Aiming at the above disadvantages, this application starts with integrating the three independent switched-mode power supplies first: exploring a new structure of the power circuit for the LED BLDC ceiling fan light with only one switched-mode power supply. Obviously, the brushless DC motor 106 needs to be supported by a DC constant voltage power supply 110 with sufficient high power, and a motor control circuit 120 with a powerful algorithm supported by a 32-bit MCU. That is to say, the DC / DC constant voltage circuit 110 is indispensable. Therefore, we can only find a solution in the switched constant current driving circuits 140 / 150 for the two light sources: changing the switched constant current circuit in the existing solution to a lower-cost linear constant current circuit, and the key is to remove the large-volume inductor.

[0178] The light source power of ordinary LED BLDC ceiling fan lights is generally relatively large, usually between 20W and 60W, suitable for large indoor spaces, such as those over 20 square meters. However, due to structural and cost limitations, the light source power of the low-cost LED BLDC bulb ceiling fan light is smaller than that of ordinary LED ceiling fan lights, generally between 8W and 16W, suitable for relatively small indoor spaces, such as those under 15 square meters. The LED configuration of each light source is basically between 2 parallel and 18 to 25 series, that is, the working voltage of each light source is between 54V and 75V, and the working current is about 220mA. Figure 4In it, a two-channel LED light source linear constant current driving chip 240, plus two resistors 203 and 204 with constant current settings, directly replace Figure 1 18 components in the switching constant current driving circuits 140 and 150 in Figure 5 It is a schematic diagram of an internal error amplifier. The PWM signals DIM1 / DIM2 with dimming information are sent to the multiplier 245, and the duty cycles of DIM1 / DIM2 are multiplied by the reference voltage REF1, that is, REF1*D(DIM). The result is output to the positive input terminal of the error amplifier EA246. The output terminal of the EA is connected to the gate of the NMOS power switch. The internal error amplification circuit structures corresponding to the two-channel light sources are the same. The function of the multiplier 245 is to convert the digital dimming signal into an analog dimming signal, aiming to improve the experience of end users. For example, dimming will not cause the light source to flicker. The constant current output size is determined by three factors: the duty cycle of the dimming signal DIM, the reference voltage REF1, and the resistance values of the resistors 203 and 204, summarized as the following formula: I OUT = D(DIM)*REF1 / R 203 .

[0179] Since all the energy of the light source comes from the 24V constant voltage output of the DC / DC constant voltage circuit 110, the two new LED light sources 201 and 202 need to adopt different LED series-parallel configurations, which need to be changed from 8 series 4 parallel to 6 parallel. The working voltage is fixed at about 24V, and the working current range is between 350mA and 700mA. The light source power can basically cover the range of 8W to 16W. However, as is well known, the energy conversion efficiency of the linear constant current circuit depends severely on external conditions, which is very different from the switching constant current circuit Figure 1 The conversion efficiency of the switching constant current circuits 140 / 150 in Figure 4 can easily reach more than 93%. And

[0180] The conversion efficiency η calculation formula of the linear constant current circuit in LED η = V DRAIN / 24 = (24 - V

[0181] V DRAIN is the drain voltage of the NMOS power transistor.

[0182] It can be seen that under the condition of constant current output, the closer the operating voltage VLED of the light source is to the output voltage of 24V of the constant voltage circuit 110, that is, the lower the drain voltage of the NMOS power switches 242 / 243 inside the constant current chip 240, the higher the conversion efficiency of the LED light source linear constant current drive chip 240. Therefore, the two-way light sources 201 / 202 selecting an 8-series 3V LED configuration are the basic conditions for obtaining a higher conversion efficiency. However, the problem cannot be solved in the above way: First, there is an error in the output voltage of the constant voltage circuit 110, generally + / −5%, that is, there is an error of + / −1.2V; Second, even on the premise of a constant operating current, due to the fluctuations in the manufacturing process, there will also be an error of + / −5% in the operating voltage of the LED lamp beads; Third, due to the influence of the operating environment temperature, the operating voltage of the LED lamp beads will also change. Even considering only the influence of the first two factors, when the output voltage of the constant voltage circuit 110 is maximally on the high side to 25.2V and the light source lamp bead voltage VLED is on the low side to 22.8V, the conversion efficiency calculated by formula (1) is 90%; when the output voltage of the constant voltage circuit 110 may also be on the low side to 22.8V and the light source lamp bead voltage VLED is on the high side to 25.2V, this will cause the operating current of the light source not to meet the requirements, and the operating current may be less than half of the normal operating current, which is obviously not allowed. To solve this problem, the output voltage of the constant voltage circuit 110 should be increased from 24V to at least 26.5V. In this way, the lowest conversion efficiency calculated by formula (1) is only 86%. Considering that the conversion efficiency of the constant voltage circuit 110 is generally only about 90%, the total energy conversion efficiency of the light source drive circuit is 86% * 90% = 77%, which is much lower than Figure 1 the energy conversion efficiency of 93% of the switching constant current drive circuits 140 / 150 in

[0183] There are two solutions: One is to improve the accuracy of the output voltage of the constant voltage circuit 110, for example, from + / −5% to + / −1%, and improve the accuracy of the light source operating voltage. This manual matching method has two disadvantages: One is the high cost, and the other is that the accuracy of these two parameters is also affected by the operating environment temperature. Therefore, this method is not advisable and not reliable. Another method is to find a method for automatic matching of the CV power supply and VLED without manual participation. According to formula (1): No matter how much the errors of the CV power supply and VLED are, as long as the VDRAIN voltage in formula 1 is automatically ensured to be small enough in some way, for example, equal to 0.7V, the loss of the LED light source linear constant current drive chip 240 is only about 3%, which is acceptable.

[0184] Figure 6 It is a schematic diagram of a circuit implementation of this automatic matching idea. Inside the new LED light source linear constant current drive chip 340, there is a negative feedback circuit 341, which outputs a feedback signal FBM to the constant voltage circuit 310. That is to say, the feedback circuit 341 and the constant voltage circuit 310 cooperate with each other to always automatically maintain the drain voltage of the NMOS power tube at around 0.7V. Figure 7 It is a detailed internal schematic diagram of the connection between the negative feedback circuit 341 and the constant voltage circuit 310. The negative feedback circuit 341 first selects the lower of the two drain voltages as DMIN, and then generates a controlled current source with the reference voltage REF2 (such as 0.7V). Inside the controlled current source 346, there is actually a subtractor with a proportionality coefficient. (DMIN - REF2) multiplied by the proportionality coefficient 1 / R is the magnitude of the output current. The new constant voltage circuit 310 only adds two components, a resistor 311 and a capacitor 312. After the feedback current output by the feedback circuit 341 enters the constant voltage circuit 310, a voltage drop equal to (DMIN - REF2)*R311 / R will be generated on the resistor 311. R311 is relatively close to the value of R. If the two are equal, the feedback FBM voltage is equal to (DMIN - REF2). Here, it is assumed that (R116 + R115) / R115 is equal to 24. If the output CV voltage is 24V when FBM = 0, then when FBM = (DMIN - REF2) rises to 0.1V (that is, DMIN rises to 0.8V), the CV voltage will decrease by FBM*24 = 2.4V. That is to say, the CV voltage will drop from 24V to 21.6V. This is the negative feedback control process. As a result, the DMIN voltage will be automatically controlled not far above 0.7V, ensuring that the power consumption of the LED light source linear constant current drive chip 340 is at a low level. Now, explain the reason for choosing the lower drain voltage. For example, when only one light source is turned on, the drain voltage of the corresponding NMOS power tube is low, while the other light source is turned off, and the corresponding NMOS power tube does not work, so the drain voltage must be high. Clearly, it is reasonable to choose the lower drain voltage to participate in the feedback control, and it is wrong to choose the higher drain voltage to participate in the feedback control.

[0185] Figure 6 and Figure 7 In this automatic matching circuit, the reference voltage REF2 is determined artificially, and it is difficult to balance efficiency and performance at the same time. To ensure performance, REF2 is more inclined to sacrifice efficiency. In fact, the optimal drain reference voltage is to make the NMOS power tube work in the deep linear region, far from the saturation region. Figure 6 / Figure 7This method is more likely to cause the power transistor to enter the saturation region, resulting in an increase in the power consumption of the power transistor. The following is a simple theoretical analysis. Equation (2) is the formula for calculating the maximum loss of the power transistor. The maximum output current IMAX is fixed (the maximum output current corresponds to the maximum brightness of the light source). The first half of the equation indicates that a lower drain-source voltage V DS will result in lower losses. This is the Figure 6 and Figure 7 theoretical basis; the second half of Equation (2) shows that the smaller the source-drain on-resistance R DS of the power transistor, the smaller the power loss of the power transistor. According to semiconductor theory, the source-drain on-resistance of the MOS transistor in the linear region is much smaller than that in the saturation region. It can be seen that semiconductor theory indicates that the power transistor should operate in the linear region and stay as far away from the saturation region as possible. Similarly, according to semiconductor theory, Equation (3) is the expression for the on-resistance of an NMOS transistor operating in the linear region, where μ is the electron mobility, C OX is the gate oxide capacitance per unit area, W is the channel width, L is the channel length, V GS is the gate-source voltage, and V TH is the threshold voltage. In Equation (3), only the gate-source voltage V GS is a variable, and the others are fixed constants, indicating that the larger the gate-source voltage V GS , the lower the on-resistance R DS . Therefore, according to semiconductor theory, to obtain the lowest possible power loss of the power transistor, it is necessary to increase the gate-source voltage V GS as much as possible. For current typical semiconductor processes, the maximum gate-source voltage of integrated NMOS power transistors is generally 5V. As long as the gate-source voltage VGS is made as close to 5V as possible.

[0186] P LOSS = I MAX * V DS = I 2 MAX * R DS (2)

[0187] R DS = L / (μ * Cox * W(V GS - V TH ))(3)

[0188] Figure 8 is the schematic diagram of the automatic matching circuit for the power transistor to operate in the linear region, Figure 9It is a detailed internal schematic diagram of the connection between the negative feedback circuit 441 and the constant voltage circuit 310. The negative feedback control variable is the gate voltage of the power transistor, which is also the output voltage EAO of the corresponding error amplifier EA. The gate voltage of the larger one of the two power transistors is selected, and then a controlled current source 446 outputs current by generating a controlled current source with the reference voltage REF3 (such as 4.5V). Inside the controlled current source 446, there is actually a subtractor with a proportionality coefficient (REF3 - GMAX). (REF3 - GMAX) multiplied by the proportionality coefficient 1 / R is the magnitude of the output current of the controlled current source 446. After the feedback current output by the feedback circuit 441 enters the constant voltage circuit 310, a voltage drop equal to (REF3 - GMAX)*R311 / R will be generated on the resistor 311. R311 is relatively close to the value of R. If the two are equal, the feedback FBM voltage will be equal to (REF3 - GMAX). Here, it is also assumed that (R116 + R115) / R115 is equal to 24. If the output CV voltage is 24V when FBM = 0, then when FBM = (REF3 - GMAX) rises to 0.1V (that is, GMAX drops to 4.4V), the CV voltage will drop by FBM*24 = 2.4V, that is, the CV voltage will drop from 24V to 21.6V. This is the negative feedback control process. The result is that the GMAX voltage will be controlled not far below 4.5V, ensuring that the power consumption of the LED light source linear constant current drive chip 440 is at the lowest level. At this time, the corresponding VDS is very low. Under normal circumstances, the chip loss can be made less than 1% of the light source power.

[0189] Here, an explanation is given as to why REF3 is selected as 4.5V instead of the maximum 5V. If REF3 = 5V is selected, it will cause the error amplifier to not work properly because the operating voltage of the error amplifier is also 5V. Selecting REF3 = 4.5V can ensure that the error amplifier has good control loop gain and response bandwidth. Of course, the chip loss when REF3 takes 4.5V is definitely a little larger than when REF3 takes 5V, but this difference is really too small to be ignored.

[0190] Finally, for Figure 8 and Figure 9 (also applicable to Figure 6 and Figure 7)A brief explanation is given on the gain and frequency response bandwidth of the negative feedback circuit. The negative feedback circuit composed of the FBM signal is a complex cross-system feedback control, involving a linear constant-current feedback control loop and also the feedback control loop inside the constant-voltage circuit. The loop gains of the latter two small feedback control loops are relatively large, generally above 1000. The loop frequency response bandwidth of the linear constant-current is as high as above 100 kHz, while the feedback loop frequency response bandwidth of the constant-voltage circuit is a bit smaller, usually above 1 kHz. To ensure that each loop does not affect each other, the gain and frequency response bandwidth of the large loop feedback loop composed of the FBM signal should be much smaller than those of the two small loops. In popular terms, it means that the response speed of the large feedback loop should be slow enough and the control accuracy should not be high; while the requirements for the two small loops are completely different, they are required to respond fast enough and have high enough control accuracy. As mentioned in the previous analysis, the gain of the large feedback loop can be roughly expressed as formula 4. If R is equal to R311, the gain is equal to (R116 + R115) / R115, generally between 20 and 30, much smaller than the gains of the other two small loops. The function of the capacitor 312 connected in parallel across the resistor 311 is to reduce the frequency response bandwidth of the large loop, that is, to reduce the response speed of the loop. The large loop bandwidth can be roughly expressed as formula 5. If the resistor 311 is 100 ohms and the capacitor 312 is 100 uF, then BW is about 16 Hz, much lower than the 1 kHz bandwidth of the small feedback loop of the constant-voltage circuit 310, meeting the requirements. It should be noted that both formula 4 and formula 5 are not exact expressions, but only rough approximations.

[0191] Gain~(R 116 +R 115 )*R 311 / (R*R 115 )(4)

[0192] BW~1 / (2Π*R 311 *C 312 )(5)

[0193] There are more than just Figure 7 and Figure 9 for the specific connection implementation methods of the negative feedback circuit and the constant-voltage circuit. There can be other forms, such as Figure 10 , directly sending the FBM signal to a pin of the control chip 411 inside the constant-voltage circuit 410. The chip 411 integrates the Figure 7 and Figure 9 circuit functions of the resistor 311 and the capacitor 312 in Figure 10 . Although the circuit form of Figure 7 is more concise and the redesigned constant-voltage control chip 411 may work more reliably, the working principle is the same as that of Figure 9The principle is the same and there is no essential difference. Therefore, this article will no longer elaborate on Figure 10 the constant voltage control chip 411 in

[0194] Although the starting point of this application is a low-cost LED BLDC ceiling fan light solution, if the operating voltage of the fan motor is increased from 24V to 48V or higher, that is, the output voltage of the constant voltage circuit is above 48V, then the technology of the present invention can also be used to develop a high-power LED BLDC ceiling fan light solution with a light source power between 20W and 50W. That is to say, the technology of the present invention is applicable to the development of the full series of LED BLDC ceiling fan light solutions. Figure 11 is the schematic diagram of the currently mature intelligent lighting circuit, which is Figure 1 The biggest difference from the LED BLDC ceiling fan light control circuit is that the former does not have a BLDC motor and a complex BLDC motor drive circuit, and only a relatively simple remote control circuit 220 remains. Figure 12 is the schematic diagram of the new generation intelligent lighting circuit using the technology of the present invention. It can be clearly seen that removing Figure 8 the motor and its drive circuit in Figure 12 leaves Figure 12 It can be seen that the principle of the new generation intelligent lighting circuit Figure 8 can be completely regarded as a subset of the principle of the new generation LED BLDC ceiling fan light control circuit Figure 12 or a simplified version, and the principle is exactly the same. In view of this, this article will no longer repeat the description of the principle of the new generation intelligent lighting circuit

[0195] In this application, specific examples are used to elaborate on the principle and implementation manner of this application. The description of the above embodiments is only used to help understand the method and its core idea of this application; at the same time, for those of ordinary skill in the art, according to the idea of this application, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to this application.

Claims

1. A LED brushless DC motor fan light power supply control circuit, characterized in that: include: Switching rectifier circuit, DC / DC constant voltage circuit, remote control and motor control circuit and LED light source linear constant current driver chip; The remote control and motor control circuit are respectively connected to the brushless DC motor, the intelligent signal sensor, the switch rectification circuit, the DC / DC constant voltage circuit and the LED light source linear constant current drive chip; The DC / DC constant voltage circuit is also connected to the switch rectifier circuit; the DC / DC constant voltage circuit is also connected to the LED light source linear constant current driver chip through the third LED light source and the fourth LED light source; the DC / DC constant voltage circuit is negatively feedback connected to the LED light source linear constant current driver chip.

2. The LED brushless DC motor fan lamp power supply control circuit according to claim 1, characterized in that: The switch rectifier circuit comprises: A switch, a rectifier bridge, a first resistor, a second resistor, a third resistor, a fourth resistor and a third voltage regulator tube; The first end of the switch is connected to the first output end of the AC power supply; The second end of the switch is connected to the first end of the rectifier bridge; The second end of the rectifier bridge is connected to the first end of the DC / DC constant voltage circuit; The third end of the rectifier bridge and the first end of the first resistor are both connected to the second output end of the AC power supply; The fourth end of the rectifier bridge, the first end of the second resistor, the positive electrode of the third voltage regulator tube, the first end of the third resistor and the first end of the fourth resistor are all grounded as well as the first end of the LED light source linear constant current driver chip; The second end of the third resistor is connected to the second end of the LED light source linear constant current driver chip; The second end of the fourth resistor is connected to the third end of the LED light source linear constant current driver chip; The second end of the first resistor, the second end of the second resistor and the negative electrode of the third voltage regulator are all connected to the first end of the remote control and motor control circuit.

3. The LED brushless DC motor fan lamp power supply control circuit according to claim 2, characterized in that: The DC / DC constant voltage circuit comprises: A transformer, a fourth diode, a fifth resistor, a sixth resistor, a seventh resistor, a first capacitor, and a second capacitor; The primary coil of the transformer serves as the first end of the DC / DC constant voltage circuit; The first end of the secondary coil of the transformer is respectively connected to the anode of the fourth diode and the first end of the fifth resistor; The cathode of the fourth diode and the first end of the first capacitor are connected as the second end of the DC / DC constant voltage circuit, and are respectively connected to the second end of the remote control and motor control circuit, the fourth end of the LED light source linear constant current driver chip, the anode of the third LED light source, and the anode of the fourth LED light source; The cathode of the third LED light source is connected to the fifth end of the LED light source linear constant current driver chip; The cathode of the fourth LED light source is connected to the sixth end of the LED light source linear constant current driver chip; The second end of the fifth resistor is connected to the first end of the sixth resistor to serve as the third end of the DC / DC constant voltage circuit; The second end of the sixth resistor, the first end of the seventh resistor and the first end of the second capacitor are connected as the fourth end of the DC / DC constant voltage circuit, and connected to the seventh end of the LED light source linear constant current driver chip; The second end of the secondary coil of the transformer, the second end of the seventh resistor, the second end of the first capacitor and the second end of the second capacitor are all grounded.

4. The LED brushless DC motor fan lamp power supply control circuit according to claim 3, characterized in that: The LED light source linear constant current driver chip comprises: A first linear constant current circuit, a second linear constant current circuit and a feedback circuit; The first linear constant current circuit and the second linear constant current circuit are both connected to the feedback circuit; The first linear constant current circuit is also connected to the first dimming signal output terminal of the remote control and motor control circuit and the cathode of the third LED light source respectively; The second linear constant current circuit is also connected to the second dimming signal output terminal of the remote control and motor control circuit and the cathode of the fourth LED light source respectively; The feedback circuit is also connected to the fourth end of the DC / DC constant voltage circuit.

5. The LED brushless DC motor fan lamp power supply control circuit according to claim 4, characterized in that: The first linear constant current circuit comprises: A first multiplier, a first error amplifier and a first MOS power switch tube; The input terminal of the first multiplier is connected to the first dimming signal output terminal of the remote control and motor control circuit; The output terminal of the first multiplier is connected to the positive input terminal of the first error amplifier; The negative input terminal of the first error amplifier is connected to the source of the first MOS power switch tube and the second end of the third resistor respectively; The output end of the first error amplifier is connected to the gate of the first MOS power switch tube; The drain of the first MOS power switch tube is connected to the cathode of the third LED light source and the feedback circuit.

6. The LED brushless DC motor fan lamp power supply control circuit according to claim 5, characterized in that: The second linear constant current circuit comprises: A second multiplier, a second error amplifier and a second MOS power switch tube; The input terminal of the second multiplier is connected to the second dimming signal output terminal of the remote control and motor control circuit; The output terminal of the second multiplier is connected to the positive input terminal of the second error amplifier; The negative input terminal of the second error amplifier is connected to the source of the second MOS power switch tube and the second end of the fourth resistor respectively; The output end of the second error amplifier is connected to the gate of the second MOS power switch tube; The drain of the second MOS power switch tube is connected to the cathode of the fourth LED light source and the feedback circuit.

7. The LED brushless DC motor fan lamp power supply control circuit according to claim 6, characterized in that: The feedback circuit comprises: A first comparator, a first field effect transistor, a second field effect transistor, a first negation device and a first controlled current source; The positive input terminal of the first comparator is respectively connected to the drain of the first MOS power switch tube, the cathode of the third LED light source, and the drain of the second field effect tube; The negative input terminal of the first comparator is respectively connected to the drain of the second MOS power switch tube, the cathode of the fourth LED light source and the drain of the first field effect tube; The source of the first field effect transistor and the source of the second field effect transistor are connected to the input terminal of the first controlled current source; The output terminal of the first comparator is connected to the input terminal of the first negation device and the gate of the first field effect transistor respectively; The output end of the first negation device is connected to the gate of the second field effect transistor.

8. The LED brushless DC motor fan lamp power supply control circuit according to claim 4, characterized in that: The first linear constant current circuit comprises: A first multiplier, a first error amplifier and a first MOS power switch tube; The input terminal of the first multiplier is connected to the first dimming signal output terminal of the remote control and motor control circuit; The output terminal of the first multiplier is connected to the positive input terminal of the first error amplifier; The negative input terminal of the first error amplifier is connected to the source of the first MOS power switch tube and the second end of the third resistor respectively; The output end of the first error amplifier is connected to the gate of the first MOS power switch tube; The drain of the first MOS power switch tube is connected to the cathode of the third LED light source; The gate of the first MOS power switch tube is connected to the feedback circuit.

9. The LED brushless DC motor fan lamp power supply control circuit according to claim 8, characterized in that: The second linear constant current circuit comprises: A second multiplier, a second error amplifier and a second MOS power switch tube; The input terminal of the second multiplier is connected to the second dimming signal output terminal of the remote control and motor control circuit; The output terminal of the second multiplier is connected to the positive input terminal of the second error amplifier; The negative input terminal of the second error amplifier is connected to the source of the second MOS power switch tube and the second end of the fourth resistor respectively; The output end of the second error amplifier is connected to the gate of the second MOS power switch tube; The drain of the second MOS power switch tube is connected to the cathode of the fourth LED light source; The gate of the second MOS power switch tube is connected to the feedback circuit.

10. The LED brushless DC motor fan lamp power supply control circuit according to claim 9, characterized in that: The feedback circuit comprises: A second comparator, a first field effect transistor, a second field effect transistor, a first negation device, and a second controlled current source; The negative input terminal of the second comparator is respectively connected to the gate of the first MOS power switch tube, the cathode of the third LED light source and the drain of the second field effect tube; The positive input terminal of the second comparator is respectively connected to the gate of the second MOS power switch tube, the cathode of the fourth LED light source and the drain of the first field effect tube; The source of the first field effect transistor and the source of the second field effect transistor are connected to the input terminal of the second controlled current source; The output terminal of the second comparator is connected to the input terminal of the non-logic device and the gate of the first field effect transistor respectively; The output terminal of the second comparator is connected to the input terminal of the first negation device and the gate of the first field effect transistor respectively; The output end of the first negation device is connected to the gate of the second field effect transistor.

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