CN216626110U

CN216626110U - Dimming control circuit, dimmer, drive circuit and lighting device

Info

Publication number: CN216626110U
Application number: CN202122886753.5U
Authority: CN
Inventors: 陈志钦; 林明伟; 李炎坤; 刘宗源
Original assignee: Leedarson Lighting Co Ltd
Current assignee: Leedarson Lighting Co Ltd
Priority date: 2021-11-23
Filing date: 2021-11-23
Publication date: 2022-05-27
Anticipated expiration: 2031-11-23

Abstract

A dimming control circuit and a lighting device are provided, the dimming control circuit includes: the first communication circuit is connected with a DALI bus or a PUSH key control circuit and is used for receiving a DALI control signal transmitted by the DALI bus or a PUSH control signal transmitted by the PUSH key control circuit; the second communication circuit is used for connecting an external control device to receive the serial control signal; a control circuit connected with the first communication circuit and the second communication circuit, the control circuit configured to output a dimming control signal for controlling a driving power supply circuit connected with the control circuit according to the DALI control signal or the PUSH control signal and/or the serial control signal. The method and the device can reduce the hardware requirement on the DALI system, namely reduce the cost and the wiring requirement of the DALI system, and have more control modes, thereby being convenient for controlling and adjusting the driving power circuit.

Description

Dimming control circuit, dimmer, drive circuit and lighting device

Technical Field

The application belongs to the technical field of lighting control, and particularly relates to a dimming control circuit, a dimmer, a driving circuit and a lighting device.

Background

A Digital Addressable Lighting Interface (DALI) is a main control protocol of european Lighting fixtures, and a DALI system generally comprises a DALI control host, a DALI bus power supply system, and a DALI fixture. The traditional DALI lamps and lanterns must match DALI control host computer, DALI bus power supply system, just can realize light control, and DALI control also must endure its complicated wiring mode and expensive system when bringing convenience for lighting control.

SUMMERY OF THE UTILITY MODEL

An object of the application is to provide a dimming control circuit, a dimmer, a driving circuit and a lighting device, and aims to solve the problems that a control circuit of a traditional DALI system is complex and high in cost.

A first aspect of an embodiment of the present application provides a dimming control circuit, including: the first communication circuit is connected with a DALI bus or a PUSH key control circuit and is used for receiving a DALI control signal transmitted by the DALI bus or a PUSH control signal transmitted by the PUSH key control circuit; the second communication circuit is used for connecting the external control equipment to receive the serial control signal; a control circuit connected with the first communication circuit and the second communication circuit, the control circuit configured to output a dimming control signal for controlling a driving power supply circuit connected with the control circuit according to the DALI control signal or the PUSH control signal and/or the serial control signal.

In one embodiment, the first communication circuit comprises a control interface, a rectifying circuit, a current limiting circuit and an isolating circuit which are connected in sequence; the control interface is used for being connected with the DALI bus or the PUSH key control circuit; the rectifying circuit is used for converting the PUSH control signal input from the control interface from an alternating current signal to a direct current pulse signal or converting the DALI control signal from a signal with polarity to a direct current pulse signal with specified polarity; the current limiting circuit is used for adjusting the current of the direct current pulse signal output by the rectifying circuit; the isolation circuit is connected with the control circuit and used for avoiding the influence of analog signals on the work of the control circuit.

In one embodiment, the first communication circuit further includes a feedback circuit, the feedback circuit is disposed between the control circuit and the rectifying circuit, and the feedback circuit is configured to change the voltage of the DALI bus by adjusting the voltage of the rectifying circuit according to a feedback signal output by the control circuit.

In one embodiment, the rectifier circuit further comprises an overcurrent protection circuit, the overcurrent protection circuit is arranged between the feedback circuit and the rectifier circuit, and the overcurrent protection circuit is configured to turn off the feedback circuit when the current transmitted to the rectifier circuit by the feedback circuit is too large.

In one embodiment, the PUSH button control circuit is disposed between the DALI bus and a power supply line, and the PUSH control signal is an ac signal loaded on the power supply line.

In one embodiment, the control circuit includes a master control module configured to output an analog dimming signal and/or a PWM dimming signal according to the DALI control signal or the serial control signal, and a dimming circuit configured to output the dimming control signal according to the analog dimming signal and/or the PWM dimming signal.

In one embodiment, the dimming circuit comprises a following operational amplifier unit and a third switching tube, wherein an input end of the following operational amplifier unit is connected with the main control module, a first conducting end of the third switching tube is connected with an output end of the following operational amplifier unit, a second conducting end of the third switching tube is grounded, a control end of the third switching tube is connected with the main control module, and the third switching tube is used for performing PWM dimming on an analog dimming signal passing through the following operational amplifier unit according to the PWM dimming signal to generate the dimming control signal.

A second aspect of the embodiments of the present application provides a dimmer including the dimming control circuit as described above.

A third aspect of the embodiments of the present application provides a driving circuit of an LED, including a driving power circuit for driving the LED, and further including the dimming control circuit as described above, where the dimming control circuit is connected to the driving power circuit, and the dimming control circuit outputs a dimming control signal to the driving power circuit to adjust light emission of the LED.

A fourth aspect of the embodiments of the present application provides an LED lighting device, which includes an LED light emitting module and an LED driving circuit as described above, which are connected in sequence, where the LED driving circuit is used to control the LED light emitting module to emit light.

Compared with the prior art, the embodiment of the application has the advantages that: if the dimming control signal is generated only by the DALI control signal, a complex and costly DALI control circuit is required to achieve overall control of the driving power supply circuit, and the dimming control circuit can receive different control signals and output corresponding dimming control signals in three ways to achieve control of the driving power supply circuit. The PUSH key control circuit and the second communication circuit are used as supplements of the dimming control circuit, so that the compatibility is higher, and the hardware requirement on the DALI system can be reduced, namely the cost and the wiring requirement of the DALI system are reduced. The embodiment of the application has more control modes, and is convenient for controlling and adjusting the driving power circuit.

Drawings

Fig. 1 is a schematic block diagram of a dimming control circuit according to an embodiment of the present application;

fig. 2 is a circuit diagram of a dimming control circuit according to an embodiment of the present application;

fig. 3 is a circuit diagram of a dimming control circuit according to another embodiment of the present application.

The above figures illustrate: 100. a first communication circuit; 110. a control interface; 120. a rectifying circuit; 130. a current limiting circuit; 140. an isolation circuit; 150. a feedback circuit; 200. PUSH key control circuit; 300. a second communication circuit; 400. a control circuit; 410. a main control module; 420. a dimming circuit; 421. a following operational amplifier unit; 500. a power supply circuit is driven.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present application clearer, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.

It will be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like, refer to an orientation or positional relationship illustrated in the drawings for convenience in describing the present application and to simplify description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present application.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

Fig. 1 shows a schematic block diagram of a dimming control circuit provided in a first embodiment of the present application, and for convenience of description, only the portions related to the present embodiment are shown, and detailed descriptions are as follows:

as shown in fig. 2, a dimming control circuit includes a first communication circuit 100, a second communication circuit 300, and a control circuit 400.

Wherein the first communication circuit 100 may be connected with a DALI bus, and at the same time, the first communication circuit 100 may receive a DALI control signal transmitted by the DALI bus. The second communication circuit 300 can be connected to an external control device and receive serial control signals transmitted by the external control device. The control circuit 400 is connected to the first communication circuit 100 and the second communication circuit 300 at the same time, the control circuit 400 is configured to output a dimming control signal according to the DALI control signal and/or the serial control signal, the dimming control signal is used for controlling the driving power circuit 500 connected to the control circuit 400, the driving power circuit 500 is used for connecting and driving the LED light emitting module to emit light, and the dimming control signal can control dimming and color mixing of the driving power circuit 500. In the DALI system, a plurality of dimming control circuits including the first communication circuit 100 are provided to control the different driving power circuits 500, respectively.

The second communication circuit 300 includes a serial communication interface PORT, the serial communication interface PORT is connected to the control circuit 400 and the external control device, and the control circuit 400 can be connected to the external control device through the serial communication interface PORT, so as to control the driving power supply circuit 500 according to the serial control signal sent by the external control device, for example, the serial communication interface PORT can be connected to a mobile phone or a remote controller, thereby realizing fast control.

In this embodiment, the first communication circuit 100 includes a control interface 110, a rectifying circuit 120, a current limiting circuit 130, and an isolating circuit 140, which are connected in sequence; the control interface 110 is used for connection to the DALI bus. The DALI bus comprises a positive communication bus DA + and a negative communication bus DA-, and the isolation circuit 140 is connected with the control circuit 400.

The rectifying circuit 120 includes a first rectifying diode D1, a second rectifying diode D2, a third rectifying diode D3, and a fourth rectifying diode D4. The cathode of the first rectifying diode D1 is connected to the cathode of the second rectifying diode D2, and the connection point is the dc output end of the rectifying circuit 120. The cathode of the third rectifying diode D3 is connected to the anode of the fourth rectifying diode D4, and the connection point is the dc input end of the rectifying circuit 120. The anode of the first rectifying diode D1 is connected to the cathode of the fourth rectifying diode D4, and the connection point is the first signal input terminal of the rectifying circuit 120. The anode of the second rectifying diode D2 is connected to the cathode of the third rectifying diode D3, and the connection point is the second signal input terminal of the rectifying circuit 120. The rectifying circuit 120 can convert the DALI control signal input from the control interface 110 from a signal with polarity to a dc pulse signal with designated polarity, and since the input DALI control signal is different between a positive signal and a negative signal, the conversion of the signal input to the rectifying circuit 120 into the dc pulse signal with designated polarity can facilitate the subsequent circuits to read, identify and process the instructions in the input signal.

In this embodiment, the first signal input terminal may be connected to the positive communication bus DA + via the control interface 110, and the second signal input terminal may be connected to the negative communication bus DA-via the control interface 110.

As shown in fig. 3, in another embodiment, the PUSH button control circuit 200 is disposed between the control interface 110 and a power supply line, the power supply line includes a live line L and a neutral line N, the PUSH button control circuit 200 is configured to transmit a PUSH control signal to the control interface 110, and the PUSH control signal is an ac signal on the power supply line. Specifically, the PUSH button control circuit 200 includes a resilient switch SW, the first signal input end of the rectifying circuit 120 may be connected to the live line L sequentially through the control interface 110 and the resilient switch SW, and the second signal input end of the rectifying circuit 120 may be connected to the neutral line N through the control interface 110. After the resilient switch SW is triggered, the PUSH control signal passes through the rectifying circuit 120 and is converted from an ac signal to a dc pulse signal, and then is transmitted to the main control module 410 through the first communication circuit 100, and then the main control module 410 can identify the signal according to the frequency of the signal input to the main control module 410, and the control circuit 400 outputs a corresponding dimming control signal. The PUSH button control circuit 200 may transmit the PUSH control signal to the dimming control circuit, so as to realize independent control of each dimming control circuit without additional control lines and hardware devices of the DALI system. Compared with a DALI bus, the PUSH key control circuit 200 is more flexible and simpler in installation, use and maintenance and lower in cost.

The current limiting circuit 130 comprises a first current limiting tube Q1, a second current limiting tube Q2, a first current limiting resistor R1 and a second current limiting resistor R2, a first end of the first current limiting resistor R1 is connected with a direct current output end of the rectifying circuit 120, a first conduction end of the first current limiting tube Q1 is connected with a direct current output end of the rectifying circuit 120, a control end of the first current limiting tube Q1 is connected with a second end of the first current limiting resistor R1, a first conduction end of the second current limiting tube Q2 is connected with a second end of the first current limiting resistor R1, a control end of the second current limiting tube Q2 is connected with a second conduction end of the first current limiting tube Q1, a first end of the second current limiting resistor R2 is connected with a control end of the second current limiting tube Q2, a second end of the second current limiting tube R2 is connected with a second conduction end of the second current limiting tube Q2, and a second conduction end of the second current limiting tube Q2 is an output end of the current limiting circuit 130.

In this embodiment, the first current limiting tube Q1 and the second current limiting tube Q2 may be PNP triodes, the first conduction end of the first current limiting tube Q1 and the second current limiting tube Q2 is an emitter of the PNP triode, the second conduction end of the first current limiting tube Q1 and the second current limiting tube Q2 is a collector of the PNP triode, and the control end of the first current limiting tube Q1 and the second current limiting tube Q2 is a base of the PNP triode.

The current limiting circuit 130 is used for adjusting the current of the dc pulse signal output by the rectifying circuit 120, so as to avoid the damage of components in the subsequent circuit due to the excessive input current.

In this embodiment, the isolation circuit 140 includes a first photo coupler U1, an input terminal of the first photo coupler U1 is connected to an output terminal of the current limiting circuit 130, and an output terminal of the first photo coupler U1 is connected to the control circuit 400. The first photocoupler U1 is used for converting the analog signal output by the current limiting circuit 130 into a digital signal, which is convenient for reading and identifying the control circuit 400, and realizes the isolation between the analog circuit and the digital circuit, so as to prevent the analog signal from influencing the normal operation of the control circuit 400.

In this embodiment, the control circuit 400 includes a main control module 410 and a dimming circuit 420, the main control module 410 may be a Micro Controller Unit (MCU), the main control module 410 is configured to output an analog dimming signal and/or a PWM (Pulse width modulation) dimming signal according to a received DALI control signal or serial control signal, and the dimming circuit 420 is configured to output a dimming control signal according to the analog dimming signal and/or the PWM dimming signal.

Specifically, one of the pins of the input terminal of the first photocoupler U1 is connected to the output terminal of the current limiting circuit 130 through a zener diode D5, and the other pin of the input terminal of the first photocoupler U1 is connected to the dc input terminal of the rectifying circuit 120. One pin of the output terminal of the first photocoupler U1 is connected with the operating power supply VCC through a pull-up current limiting resistor R8 and is connected with the main control module 410, and the other pin of the output terminal of the first photocoupler U1 is grounded.

The first communication circuit 100 further comprises a feedback circuit 150, wherein the feedback circuit 150 comprises a second photocoupler U3, a unidirectional conducting diode D6 and a first switching tube Q3; one pin of the input end of the second photocoupler U3 is connected with the main control module 410, and the other pin of the input end of the second photocoupler U3 is grounded through a pull-down current-limiting resistor R7. One pin of the output end of the second photoelectric coupler U3 is connected with the output end of the current limiting circuit 130 through a one-way conduction diode D6, the positive electrode of the one-way conduction diode D6 is connected with the output end of the current limiting circuit 130, the other pin of the output end of the second photoelectric coupler U3 is connected with the control end of the first switch tube Q3, the first conduction end of the first switch tube Q3 is connected with the direct current output end of the rectifying circuit 120, and the second conduction end of the first switch tube Q3 is connected with the direct current input end of the rectifying circuit 120. In this embodiment, the first switch Q3 may be a PMOS transistor, the first conducting terminal of the first switch Q3 is a drain of the PMOS transistor, the second conducting terminal of the first switch Q3 is a source of the PMOS transistor, and the control terminal of the first switch Q3 is a gate of the PMOS transistor.

When the main control module 410 generates a feedback signal, the feedback signal can control the on/off of the first switching tube Q3 by switching on/off the second photocoupler U3, and change the voltage at the dc input end of the rectifying circuit 120, so as to pull up or pull down the voltage of the DALI bus connected to the rectifying circuit 120 through the rectifying circuit 120, thereby transmitting the information to be fed back to the DALI host.

In this embodiment, the feedback circuit 150 includes an overcurrent protection circuit, the overcurrent protection circuit is disposed between the feedback circuit 150 and the rectification circuit 120, the overcurrent protection circuit includes a second switch tube Q4 and a detection resistor R5, the detection resistor R5 is disposed between a second conduction end of the first switch tube Q3 and a dc input end of the rectification circuit 120, a first conduction end of the second switch tube Q4 is connected to a control end of the first switch tube Q3, a second conduction end of the second switch tube Q4 is connected to the dc input end of the rectification circuit 120, and a control end of the second switch tube Q4 is connected to the second conduction end of the first switch tube Q3. When the current flowing through the detection resistor R5 is too large, the voltage at the two ends of the detection resistor R5 is too large, and reaches the driving voltage of the second switching tube Q4, so that the second switching tube Q4 is turned on, and the control end of the first switching tube Q3 is connected with the direct current input end, so that the first switching tube Q3 is turned off. In this embodiment, the second switch Q4 may be an NPN transistor, the first conducting end of the second switch Q4 is a collector of the NPN transistor, the first conducting end of the second switch Q4 is an emitter of the NPN transistor, and the control end of the second switch Q4 is a base of the NPN transistor.

In this embodiment, the dimming circuit 420 includes a following operational amplifier unit 421 and a third switching tube Q5, an input end of the following operational amplifier unit 421 is connected to the main control module 410, a first conducting end of the third switching tube Q5 is connected to an output end of the following operational amplifier unit 421, a second conducting end of the third switching tube Q5 is grounded, a control end of the third switching tube Q5 is connected to the main control module 410, and the third switching tube Q5 is configured to perform PWM dimming on the analog dimming signal passing through the following operational amplifier unit 421 according to the PWM dimming signal, and finally generate the dimming control signal.

In this embodiment, the third switching tube Q5 may be an NPN transistor, the first conducting end of the third switching tube Q5 is a collector of the NPN transistor, the first conducting end of the third switching tube Q5 is an emitter of the NPN transistor, and the control end of the third switching tube Q5 is a base of the NPN transistor.

The follower operational amplifier unit 421 includes a filter circuit and an operational amplifier U4 sequentially connected, an input terminal of the filter circuit is connected to the main control module 410, and is configured to filter an analog dimming signal output by the main control module 410, an output terminal of the filter circuit is connected to a non-inverting input terminal of the operational amplifier U4, an output terminal of the operational amplifier U4 is connected to an anode of the output diode D7, a cathode of the output diode D7 is connected to the driving power circuit 500 and is connected to an inverting input terminal of the operational amplifier U4, and the follower operational amplifier unit 421 is configured to buffer between the main control module 410 and the driving power circuit 500, so as to prevent a high voltage of the driving power circuit 500 from affecting normal operation of the main control module 410. The third switch tube Q5 can be turned off or on according to the PWM dimming signal, and converts the analog dimming signal into a dimming control signal with a PWM dimming function. The filter circuit comprises a first filter resistor R11, a second filter resistor R12 and a filter capacitor C1, the main control module 410 is connected with the first end of the first filter resistor R11, the second end of the first filter resistor R11 is grounded, the first end of the second filter resistor R12 is connected with the main control module 410, the second end of the second filter resistor R12 is connected with the non-inverting input end of the operational amplifier U4, the first end of the filter capacitor C1 is connected with the second end of the second filter resistor R12, and the second end of the filter capacitor C1 is grounded.

The embodiment further includes a first voltage-dividing resistor R3, a second voltage-dividing resistor R4, a third voltage-dividing resistor R6, a fourth voltage-dividing resistor R9, a fifth voltage-dividing resistor R10, a sixth voltage-dividing resistor R13, and a seventh voltage-dividing resistor R14.

The first voltage dividing resistor R3 is disposed between the output terminal of the current limiting circuit 130 and the positive electrode of the diode D6. The second voltage-dividing resistor R4 is disposed between the control terminal of the first switching tube Q3 and the second photo-coupler U3. The third voltage dividing resistor R6 is disposed between the first conducting terminal of the second switch Q4 and the second conducting terminal of the second switch Q4. The fourth and fifth voltage-dividing resistors R9 and R10 are disposed between the serial communication interface PORT and the main control module 410. The sixth voltage-dividing resistor R13 is provided between the cathode of the output diode D7 and the driving power supply circuit 500. The seventh voltage-dividing resistor R14 is disposed between the main control module 410 and the third switching tube Q5.

The embodiment further includes a first voltage-stabilizing capacitor C2, a second voltage-stabilizing capacitor C3, a third voltage-stabilizing capacitor C4, and a fourth voltage-stabilizing capacitor C5.

Two ends of the first voltage-stabilizing capacitor C2 are respectively connected to two pins of the input end of the first photoelectric coupler U1. Two ends of the second voltage-stabilizing capacitor C3 are respectively connected to two pins of the output end of the first photoelectric coupler U1. Two ends of the third voltage-stabilizing capacitor C4 are respectively connected to the cathode of the unidirectional conducting diode D6 and the dc input end of the rectifying circuit 120. Two ends of the fourth voltage stabilizing capacitor C5 are respectively connected to the control end of the first switch tube Q3 and the dc input end of the rectifying circuit 120.

A second embodiment of the present application provides a light modulator, which includes the above-mentioned light modulation control circuit, and the light modulator may be connected to an LED (light-emitting diode) for implementing light modulation and color modulation on the LED.

The third embodiment of the present application provides a driving circuit of an LED, which includes a driving power circuit 500 for driving the LED, and further includes a dimming control circuit as described above, where the dimming control circuit is connected to the driving power circuit 500, and the dimming control circuit is configured to output a dimming control signal to the driving power circuit 500 to adjust the color of the LED.

The fourth embodiment of the present application provides a lighting device, which includes an LED light emitting module and a driving circuit of the LED as described above, which are connected in sequence. The driving circuit of the LED can be used for driving the LED light-emitting module to emit light, and the LED light-emitting module can be an LED lamp bank.

The above-mentioned embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.

Claims

1. A dimming control circuit, comprising:

the first communication circuit is connected with a DALI bus or a PUSH key control circuit and is used for receiving a DALI control signal transmitted by the DALI bus or a PUSH control signal transmitted by the PUSH key control circuit;

the second communication circuit is used for connecting the external control equipment to receive the serial control signal;

a control circuit connected with the first communication circuit and the second communication circuit, the control circuit configured to output a dimming control signal for controlling a driving power supply circuit connected with the control circuit according to the DALI control signal or the PUSH control signal and/or the serial control signal.

2. The dimming control circuit of claim 1, wherein the first communication circuit comprises a control interface, a rectifying circuit, a current limiting circuit, and an isolation circuit connected in sequence;

the control interface is used for being connected with the DALI bus or the PUSH key control circuit; the rectifying circuit is used for converting the PUSH control signal input from the control interface from an alternating current signal into a direct current pulse signal or converting the DALI control signal from a signal with polarity into a direct current pulse signal with specified polarity; the current limiting circuit is used for adjusting the current of the direct current pulse signal output by the rectifying circuit; the isolation circuit is connected with the control circuit and used for avoiding the influence of analog signals on the work of the control circuit.

3. The dimming control circuit of claim 2, wherein the first communication circuit further comprises a feedback circuit disposed between the control circuit and the rectifying circuit, the feedback circuit being configured to vary the voltage of the DALI bus by adjusting the voltage of the rectifying circuit according to a feedback signal output by the control circuit.

4. The dimming control circuit of claim 3, further comprising an over-current protection circuit disposed between the feedback circuit and the rectification circuit, the over-current protection circuit configured to turn off the feedback circuit when the current delivered by the feedback circuit to the rectification circuit is excessive.

5. The dimming control circuit of claim 2, wherein the PUSH button control circuit is disposed between the control interface and a power supply line, and the PUSH control signal is an ac signal loaded on the power supply line.

6. The dimming control circuit of claim 1, wherein the control circuit comprises a master control module configured to output an analog dimming signal and/or a PWM dimming signal according to the DALI control signal or the serial control signal, and a dimming circuit configured to output the dimming control signal according to the analog dimming signal and/or the PWM dimming signal.

7. The dimming control circuit of claim 6, wherein the dimming circuit comprises a following operational amplifier unit and a third switching tube, an input end of the following operational amplifier unit is connected with the main control module, a first conducting end of the third switching tube is connected with an output end of the following operational amplifier unit, a second conducting end of the third switching tube is grounded, a control end of the third switching tube is connected with the main control module, and the third switching tube is configured to perform PWM dimming on an analog dimming signal passing through the following operational amplifier unit according to the PWM dimming signal to generate the dimming control signal.

8. A dimmer comprising a dimming control circuit as claimed in any one of claims 1 to 7.

9. A driving circuit of an LED, comprising a driving power circuit for driving the LED, and further comprising a dimming control circuit according to any one of claims 1 to 7, connected to the driving power circuit, the dimming control circuit outputting a dimming control signal to the driving power circuit to adjust light emission of the LED.

10. An LED lighting device, comprising an LED lighting module and the LED driving circuit according to claim 9, which are connected in sequence, wherein the LED driving circuit is configured to drive the LED lighting module to emit light.