CN113225874A

CN113225874A - LED driver

Info

Publication number: CN113225874A
Application number: CN202110205833.1A
Authority: CN
Inventors: 马瑞芳
Original assignee: Shanghai Musa Electronic Technology Co ltd
Current assignee: Shanghai Musa Electronic Technology Co ltd
Priority date: 2021-02-24
Filing date: 2021-02-24
Publication date: 2021-08-06

Abstract

The utility model relates to a technical field of LED drive especially relates to a LED driver, aims at solving the technical problem that prior art driver life is short, and its technical scheme is: the LED driving circuit comprises a main circuit and at least one standby circuit, wherein the input end of the main circuit is used for being connected with a power supply, and the output end of the main circuit is used for being connected with an LED load circuit; the input end of the main circuit is provided with a preceding stage control module for acquiring voltage and current of the main circuit, and the output end of the main circuit is provided with a subsequent stage measurement module for acquiring the working state of the LED load circuit; the preceding stage control module comprises a first measuring component and a second measuring component, wherein the first measuring component comprises a voltage detector, a voltage comparator and a first switching circuit; the voltage detector is used for acquiring voltage and current of an input end of the main circuit, and the voltage comparator is used for comparing the acquired voltage and current and outputting a level signal to the first switching circuit. The application has the technical effect of prolonging the service life of the driver.

Description

LED driver

Technical Field

The application relates to the technical field of LED driving, in particular to an LED driver.

Background

As a new type of lighting device, the LED lamp is widely used in the field of lighting due to its high luminous efficiency. The LED driver is a power supply adjusting electronic device for driving an LED to emit light or an LED module assembly to normally work.

The LED lamp is connected with the output end of the constant current module in parallel, the constant current output mode is a common LED driver on the market, the constant current LED driver is mainly used for maintaining constant current, the output power of the LED driver is relatively stable, the service life of an LED is further prolonged, and meanwhile the phenomenon of unstable light emission of the LED can be reduced by the constant current mode.

In view of the related art in the above, the inventors consider that there are drawbacks: the front end rectifier module often receives the fluctuation of electric wire netting power on the LED driver, the fluctuation of electric wire netting is very big to the damage of LED driver, and then punctures the components and parts in the drive circuit easily, and then makes the unable normal work of LED driver, therefore relevant LED driver is after the damage, the LED driver will not prove normal use, and need more renew the driver, consequently relevant LED driver's life is shorter, and causes the condition of wasting of resources easily.

Disclosure of Invention

In order to prolong the service life of the driver and reduce the condition of resource waste, the application provides the LED driver.

The application provides an LED driver adopts following technical scheme:

an LED driver comprises a main circuit and at least one standby circuit, wherein the input end of the main circuit is used for being connected with a power supply, and the output end of the main circuit is used for being connected with an LED load circuit;

the input end of the main circuit is provided with a preceding stage control module for acquiring voltage and current of the main circuit, and the output end of the main circuit is provided with a subsequent stage measurement module for acquiring the working state of the LED load circuit;

the preceding stage control module comprises a first measuring component and a second measuring component, wherein the first measuring component comprises a voltage detector, a voltage comparator and a first switching circuit;

the voltage detector is used for acquiring voltage and current of an input end of the main circuit, and the voltage comparator is used for comparing the acquired voltage and current and outputting a level signal to the first switching circuit;

the rear-stage measuring module comprises a rear-stage detecting component for monitoring and processing the LED load circuit.

By adopting the technical scheme, the main circuit is disconnected and the standby circuit is connected into the circuit after the main circuit fails by utilizing the arrangement of the main circuit and the standby circuit, and the standby circuit is utilized to maintain the normal work of the LED load circuit; meanwhile, the input end of the main circuit is detected and controlled by the preceding stage control module, when the input end of the main circuit or the voltage of a power grid fluctuates sharply, the preceding stage control module cuts off the main circuit, so that the main circuit cannot be electrified, and the effect of protecting the main circuit or the control circuit is further achieved;

the first measuring assembly is used for detecting the input end of the main circuit, the main circuit is disconnected through the first switching circuit, and the standby circuit is connected at the same time, so that the effect of continuously working the LED load circuit is achieved, and the service life of the whole driver is prolonged;

the rear-stage measuring module detects the LED load circuit, and when the current of the output end of the main circuit floats greatly, the rear-stage detecting assembly enables the main circuit to be disconnected to supply power to the LED load circuit, so that the protection effect on the LED load circuit is achieved.

Optionally, the main circuit includes a conversion circuit and a filter circuit, the first measurement component obtains a voltage and a current at an input end of the conversion circuit, and the second measurement component is configured to obtain a voltage and a current at an input end of the filter circuit;

the first switching circuit comprises a relay KM1, a normally closed switch of the relay KM1 is serially connected to the input end of the conversion circuit, and a normally open switch of the relay KM1 is serially connected to the output end of the standby circuit. The first normally closed circuit is connected in series with the input end of the conversion circuit, and the first normally open circuit is connected in series with the output end of the standby circuit.

Through adopting above-mentioned technical scheme, when first measuring subassembly detects that the input of converting circuit appears undulantly to and the main circuit can't carry out the during operation, voltage comparator will output level signal and give first switching circuit, utilize first normally closed circuit disconnection main circuit of first switching circuit, make the main circuit not work, and utilize the relay actuation back of second normally open circuit, stand-by circuit inserts the circuit, adopt the continuous LED load circuit of stand-by circuit to supply power, and then the life of extension driver.

Optionally, the second measurement component includes a current detector, a current comparator and a second switching component;

the current detector is used for acquiring voltage and current at the input end of the filter circuit, and the current comparator is used for comparing the acquired voltage and current and outputting a level signal to the second switching assembly;

the second switching assembly comprises a relay KM2, a normally closed switch of the relay KM2 is serially arranged at the input end of the filter circuit, and a normally open switch of the relay KM2 is serially arranged at the output end of the standby circuit.

By adopting the technical scheme, the second measuring component is utilized to detect and process the filter circuit, and after the filter circuit breaks down, the second switching component is utilized to switch the working state of the main circuit, so that the standby circuit is timely accessed into the circuit to supply power to the LED load circuit.

Optionally, the standby circuit includes a standby converting circuit and a standby filtering circuit, the first measurement assembly further includes a third switching circuit, and the third switching circuit includes a relay KM 3;

the first measuring assembly obtains voltage and current measuring data of the main circuit, the normally closed switch of the relay KM3 is serially connected to the input end of the filter circuit, and the normally open switch of the relay KM3 is serially connected to the input end of the standby filter circuit.

By adopting the technical scheme, the standby circuit is subjected to modular processing, and after one group of the conversion circuit and the filter circuit in the main circuit fails, the conversion circuit and the standby filter circuit form a new circuit for processing by utilizing the modular processing;

and the standby change circuit and the filter circuit are utilized to carry out normal power supply processing, compared with the original scheme, two more standby schemes are added for selection, and the service life of the whole driver is further prolonged.

Optionally, the first measurement assembly further includes a fourth switching circuit, and the fourth switching circuit includes a fourth normally open circuit;

and the fourth normally open circuit is used for connecting the standby conversion circuit and the filter circuit.

By adopting the technical scheme, the standby change circuit and the filter circuit are utilized to carry out normal power supply treatment, and compared with the original scheme, the service life of the whole driver is further prolonged.

Optionally, the standby circuit further includes a charging circuit and an energy storage module, the rear-stage detection assembly is configured to switch a working state of the LED load circuit, and the rear-stage measurement module includes a rear-stage detection assembly, a rear-stage controller, and a fourth switching circuit; the fifth switching circuit comprises a fifth normally-off circuit and a fifth normally-on circuit.

By adopting the technical scheme, the charging circuit and the energy storage module are arranged in the standby circuit, the energy storage is charged when the LED load circuit normally works, the charging circuit is used for rectifying and filtering the alternating current, finally the electric energy is stored in the energy storage module, and the energy storage module is used for supplying power after the main circuit and the standby circuit cannot work.

Optionally, a normally closed switch of the relay KM5 is connected in series to the input end of the charging circuit, and a normally open switch of the relay KM5 is connected in series to the output end of the energy storage module.

Through adopting above-mentioned technical scheme, the series connection of first normally closed circuit sets up the charging circuit input, and after fifth normally closed circuit received the signal, the relay got electric actuation, and normally closed switch will the disconnection, and normally open switch will be closed simultaneously, and then makes the circuit switch to energy storage circuit and supplies power, makes LED load circuit normal work one section long.

Optionally, an indication component is connected in series in the standby circuit, and the indication component includes an indication lamp.

Through adopting above-mentioned technical scheme, utilize the output that the indicating component establishes ties and set up energy storage circuit to when energy storage circuit began to supply power to LED load circuit, the pilot lamp will be lighted, need to change the driver for the suggestion staff circuit.

Optionally, the main circuit further comprises a voltage stabilizing circuit, the voltage stabilizing circuit is arranged at the rear end of the filter circuit in parallel, and the LED load circuit is connected with the output end of the voltage stabilizing circuit in parallel.

By adopting the technical scheme, the driver output circuit is more stable by utilizing the setting of the voltage stabilizing circuit, and the protection effect on the LED load circuit is achieved.

Optionally, the front end of the main circuit is provided with a voltage reduction circuit in series.

By adopting the technical scheme, the voltage division processing is carried out on the power voltage by utilizing the arrangement of the voltage reduction circuit, and the safety performance of the circuit is improved.

In summary, the present application includes at least one of the following beneficial technical effects:

1. by means of the arrangement of the main circuit and the standby circuit, after the main circuit breaks down, the main circuit is disconnected, the standby circuit is connected into the driver, and the standby circuit is used for maintaining normal operation of the LED load circuit; meanwhile, the input end of the main circuit is detected and controlled by the preceding stage control module, when the input end of the main circuit or the voltage of a power grid fluctuates sharply, the preceding stage control module cuts off the main circuit, so that the main circuit cannot be electrified, and the effect of protecting the main circuit or the control circuit is further achieved;

2. after the first measuring component cannot measure the voltage and the current of the main circuit, the main circuit is disconnected by using a first switching circuit, and meanwhile, a standby circuit is connected, so that the LED load circuit works normally; the rear-stage measuring module is used for detecting the LED load circuit, and when the current of the output end of the main circuit floats greatly, the rear-stage detecting assembly enables the LED load circuit to be disconnected, so that the protection effect on the LED load circuit is achieved;

3. the energy storage module is connected with the LED load circuit in parallel, when the LED load circuit works normally, the charging circuit carries out charging treatment, when the LED load circuit does not work, the charging circuit is connected with the charging power supply, so that the charging circuit supplies power to the LED load circuit, when the standby circuit and the main circuit input end power grid voltage fluctuation are overlarge, the energy storage module is utilized to enable the LED load circuit to work normally, and the protection effect on the LED load circuit is further achieved.

Drawings

Fig. 1 is a schematic view of the overall structure of a preceding stage control module according to embodiment 1 of the present application;

fig. 2 is a schematic structural view of the whole of a first measurement assembly of embodiment 1 of the present application;

FIG. 3 is a schematic view of the overall structure of embodiment 2 of the present application;

fig. 4 is a top view of embodiment 2 of the present application for embodying a handover function module;

fig. 5 is a schematic view of the overall structure of embodiment 3 of the present application.

Description of reference numerals: 1. a main circuit; 2. a standby circuit; 3. an LED load circuit; 4. a preceding stage control module; 5. a post-stage measurement module; 51. a rear-stage detection component; 52. a back-stage controller; 6. a first measurement assembly; 61. a voltage detector; 62. a voltage comparator; 63. a first switching circuit; 9. a conversion circuit; 90. a third switching circuit; 10. a filter circuit; 13. a second measurement assembly; 131. a current detector; 132. a current comparator; 133. a second switching component; 19. a standby conversion circuit; 20. a backup filter circuit; 21. a charging circuit; 22. an energy storage module; 25. a protection component; 27. an indicating component; 29. a voltage stabilizing circuit; 30. a voltage reduction circuit; 100. a fourth switching circuit; 200. and a fifth switching circuit.

Detailed Description

The present application is described in further detail below with reference to figures 1-5.

The embodiment of the application discloses an LED driver.

Example 1:

referring to fig. 1, the LED driver includes a main circuit 1 and at least one standby circuit 2, the main circuit 1 and the standby circuit 2 are connected in parallel, an input end of the main circuit 1 is connected to a power supply, an output end of the main circuit is connected to an LED load circuit 3, the power supply rectifies and filters the power supply through the main circuit 1 and then transmits a voltage to the LED load circuit 3, and the LED load works normally by emitting light after the load power supply of the main circuit 1. The front end of the main circuit 1 is provided with a preceding stage control module 4, the preceding stage control module 4 detects and controls the front end of the main circuit 1, and the main circuit 1 is disconnected after the main circuit 1 and the power grid voltage fluctuate, so that the protection effect of the main circuit 1 is achieved. Meanwhile, after the main circuit 1 is broken down, the standby circuit 2 is switched to supply power to the LED load circuit 3, so that the normal work of the LED load circuit 3 is ensured.

The output end of the main circuit 1 is provided with a rear-stage measuring module 5, the rear-stage measuring module 5 detects and processes the output voltage and current of the main circuit 1, and after the output voltage and current of the main circuit 1 fluctuate, the rear-stage measuring module 5 enables the output end of the main circuit 1 to be disconnected, so that the protection effect on the LED load circuit 3 is further achieved.

Referring to fig. 1, the front-stage control module 4 includes a first measurement component 6 and a second measurement component 13, the main circuit 1 includes a converter circuit 9 and a filter circuit 10, the first measurement component 6 is used for detecting the voltage at the input end of the converter circuit 9, the front end is used for detecting the fluctuation of the grid voltage, the second measurement component 13 is arranged at the input end of the filter circuit 10, and the second measurement component 13 is used for detecting the current of the filter circuit 10.

Referring to fig. 1 and 2, the first measuring unit 6 includes a voltage detector 61, a voltage comparator 62, and a first switching circuit 63, and the first measuring unit 6 is configured to obtain a voltage current at an input terminal of the converting circuit 9 and to transmit an obtained voltage signal of the converting circuit 9 to an inverting input terminal of the voltage comparator 62. The voltage comparator 62 is used for comparing the acquired voltage, the reference voltage at the positive phase input end of the voltage comparator 62 is used for comparing, under the condition that the difference value between the reference voltage and the comparison voltage is large, the voltage comparator 62 outputs a level signal to the first switching circuit 63, the first switching circuit 63 comprises a relay KM1, a normally closed switch KM1 in the relay KM1 is serially arranged at the input end of the main circuit 11, and a normally open switch KM1 is serially arranged at the input end of the standby circuit 22.

After the first switching circuit 63 receives the level signal, the coil of the relay KM1 is electrified and attracted, so that the normally closed switch KM1 is disconnected, the normally closed switch KM1 is disconnected, the main circuit 1 stops working, and meanwhile, after the normally open switch KM1 is closed, the standby circuit 2 is connected into the circuit, and the standby circuit 2 is used for supplying power to the LED load circuit 3.

Referring to fig. 2 and 3, the second measuring component 13 includes a current detector 131, a current comparator 132, and a second switching component 133, and the second measuring component 13 is configured to obtain a voltage current at an input terminal of the filter circuit 10 and transmit an obtained current signal of the filter circuit 10 to an inverting input terminal of the current comparator 132. The obtained voltage and current are compared by the current comparator 132, the reference current at the positive phase input end of the current comparator 62 is compared, under the condition that the difference value between the reference current and the comparison current is large, the current comparator 132 outputs a high-level signal to the second switching component 133 and the first switching circuit 63, the second switching component 133 comprises a relay KM2, a normally closed switch in the relay KM2 is serially connected to the input end of the filter circuit 10, and a normally open switch is serially connected to the output end of the standby circuit 2. After the second switching component 133 receives the level signal, the coil of the relay KM2 is electrified and attracted, so that the normally closed switch KM2 is disconnected, the normally closed switch KM2 is disconnected, the main circuit 1 stops working, and meanwhile, after the normally open switch KM2 is closed, the standby circuit 2 is connected into the circuit, and the standby circuit 2 is used for supplying power to the LED load circuit 3.

Since the current comparator 132 transmits a signal to the first switching circuit 63, the normally closed switch of the relay KM1 is also turned off, so that both the input end and the output end of the main circuit 1 are turned off, thereby achieving the effect of protecting the LED driver.

Referring to fig. 1 and fig. 2, the main circuit 1 further includes a voltage stabilizing circuit 29 disposed in parallel at the output end of the filter circuit 10, the LED load circuit 3 is connected to the output end of the voltage stabilizing circuit 29, and the voltage stabilizing circuit 29 is used to enable the driver to output a stable voltage, so as to reduce the influence of voltage fluctuation on the LED load circuit 3. The front end of the main circuit 1 is provided with a voltage reduction circuit 30 in series, the voltage reduction circuit 30 adopts an RC (resistance-capacitance) voltage reduction circuit, the RC voltage reduction circuit 30 utilizes capacitance to generate capacitive reactance under an alternating current signal with certain frequency to limit a maximum working circuit, and then working current is stable, so that the safety performance of the circuit is improved.

Example 2

The present embodiment 2 differs from embodiment 1 in that:

referring to fig. 3, the standby circuit 2 includes a standby converting circuit 19 and a standby filter circuit 20, the second measuring assembly 13 further includes the standby converting circuit 19, a third switching circuit 90 is disposed in the standby converting circuit 19, the third switching circuit 90 includes a relay KM3, a normally closed switch KM3 of the relay KM3 is disposed in series at an input end of the filter circuit 10, and a normally open switch KM3 is disposed in series at an input end of the standby filter circuit 20.

When first measuring component 6 and second measuring component 13 homoenergetic were normal measurement voltage and current, and later stage measuring module 5 can't normally work, it shows that filtering circuit 10 has line fault this moment, second measuring component 13 conveys signal to third switching circuit 90, third switching circuit 90 makes relay coil KM3 electrified, after relay coil KM3 electrified, normally closed switch KM3 disconnection, open switch KM3 with the series connection at stand-by circuit 2 input end is closed simultaneously, make stand-by filtering circuit 19 access circuit in, utilize converting circuit 9 of main circuit 1 and filtering circuit 19 of stand-by circuit 2 to supply power and handle.

Referring to fig. 4, similarly, a fourth switching circuit 100 is disposed in the standby converting circuit 19, the fourth switching circuit 100 includes a relay KM4, and a fourth normally open circuit 101 is used to connect the standby converting circuit 9 and the filter circuit 10, so that when the converting circuit 9 of the main circuit 1 fails, the standby converting circuit 19 of the standby circuit 2 and the filter circuit 10 of the main circuit 1 are used to maintain normal operation, thereby prolonging the service life of the LED driver.

Example 3

This example 3 differs from examples 1 and 2 in that:

the rear stage measuring module 5 comprises a rear stage detecting component 51 and a rear stage controller 52 for monitoring the LED load circuit 3, the rear stage measuring module 5 further comprises a fifth switching circuit 200, the fifth switching circuit 200 is used for switching the power supply of the LED load circuit 3,

the standby circuit 2 further comprises a charging circuit 21 and an energy storage module 22, and the energy storage module 22 switches the circuit to the energy storage module by using a fifth switching circuit 200 to work under the condition that the main circuit 1 and the standby circuit 2 are disconnected or the power grid voltage fluctuates.

The fifth switching circuit 200 includes a relay KM5, a normally closed switch KM5 of the relay KM5 is connected in series to an input terminal of the charging circuit, a normally open switch KM5 of the relay KM5 is connected in series to an output terminal of the energy storage module, and since the normally closed switch KM5 is connected in series to an input terminal of the charging circuit 21, the LED load circuit 3 is powered by the charging circuit 21 to the energy storage module 22 during normal operation.

The rear detection assembly 51 detects the voltage and the current of the output end of the main circuit 1, after the output voltage and the current of the main circuit 1 fluctuate abnormally or the main circuit 1 breaks down, the rear detection assembly 51 transmits the acquired signals to the rear controller 52, the rear controller 52 outputs high-level signals to the relay KM5, a coil KM5 in the relay circuit is electrified, the normally closed switch connected in series at the input end of the charging circuit is opened, the normally open switch connected in series at the energy storage module 22 is closed, and the energy storage module 22 is used for temporarily supplying power to the LED charging circuit 3.

The standby circuit 2 is provided with an indicating component 27 in series, the indicating component 27 comprises an indicating lamp connected to the output end of the energy storage circuit in series, the indicating lamp is switched on when the energy storage circuit is in a discharging working state, the indicating lamp is turned on after being switched on, and the indicating lamp is used for setting the working state of the surface energy storage module 22, so that the working state of the driver can be observed conveniently.

The implementation principle of the LED driver in the embodiment of the application is as follows: the main circuit 1 and the standby circuit 2 are arranged in parallel, and after the main circuit 1 fails, the main circuit 1 is disconnected and the standby circuit 2 is switched on to work, so that the LED load circuit 3 can work normally. Meanwhile, the standby circuit 2 is subjected to modularization processing, and after one of the conversion circuit 9 and the filter circuit 10 in the main circuit 1 fails, the conversion circuit 9 and the standby filter circuit 20 form a new circuit for processing by utilizing the modularization processing.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. An LED driver, characterized by: the LED power supply comprises a main circuit (1) and at least one standby circuit (2), wherein the input end of the main circuit (1) is connected with a power supply, and the output end of the main circuit is connected with an LED load circuit (3);

the input end of the main circuit (1) is provided with a preceding stage control module (4) for acquiring and detecting the voltage and current of the main circuit (1), and the output end of the main circuit (1) is provided with a subsequent stage measuring module (5) for acquiring the working state of the LED load circuit (3);

the preceding stage control module (4) comprises a first measurement component (6) and a second measurement component (13), the first measurement component (6) comprises a voltage detector (61), a voltage comparator (62) and a first switching circuit (63);

the voltage detector (61) is used for acquiring voltage and current at the input end of the main circuit (1), and the voltage comparator (62) is used for carrying out comparison processing on the acquired voltage and current and outputting a level signal to the first switching circuit (63);

the rear-stage measuring module (5) comprises a rear-stage detecting component (51) for monitoring and processing the LED load circuit (3).

2. An LED driver according to claim 1, wherein: the main circuit (1) comprises a conversion circuit (9) and a filter circuit (10), the first measuring component (6) is used for obtaining the voltage and the current of the input end of the conversion circuit (9), and the second measuring component (13) is used for obtaining the voltage and the current of the input end of the filter circuit (10);

the first switching circuit (63) comprises a relay KM1, a normally closed switch of the relay KM1 is serially arranged at the input end of the conversion circuit (9), and a normally open switch of the relay KM1 is serially arranged at the output end of the standby circuit (2).

3. An LED driver according to claim 2, wherein: the second measurement component (13) comprises a current detector (131), a current comparator (132) and a second switching component (133);

the current detector (131) is used for acquiring voltage and current at the input end of the filter circuit (10), and the current comparator (132) is used for carrying out comparison processing on the acquired voltage and current and outputting a level signal to the second switching component (133);

the second switching assembly (133) comprises a relay KM2, a normally closed switch of the relay KM2 is serially arranged at the input end of the filter circuit (10), and a normally open switch of the relay KM2 is serially arranged at the output end of the standby circuit (2).

4. An LED driver according to claim 2, wherein: the backup circuit (2) comprises a backup conversion circuit (19) and a backup filter circuit (20), the first measurement assembly (6) further comprises a third switching circuit (90), and the third switching circuit (90) comprises a relay KM 3;

the first measuring assembly (6) obtains voltage and current measurement data of the main circuit (1), the normally closed switch of the relay KM3 is arranged at the input end of the filter circuit (10) in series, and the normally open switch of the relay KM3 is arranged at the input end of the standby filter circuit (20) in series.

5. An LED driver according to claim 4, wherein: the first measurement assembly (6) further comprises a fourth switching circuit (100), the fourth switching circuit (100) comprising a fourth normally open circuit (101);

and the fourth normally-on circuit (101) is used for connecting the standby conversion circuit (19) and the filter circuit (10).

6. An LED driver according to claim 1, wherein: the standby circuit (2) further comprises a charging circuit (21) and an energy storage module (22), the rear-stage detection assembly (51) is used for switching the working state of the LED load circuit (3), and the rear-stage measurement module (5) comprises a rear-stage detection assembly, a rear-stage controller (52) and a fourth switching circuit (100); the fifth switching circuit (100) comprises a relay KM 5.

7. An LED driver according to claim 6, wherein: the normally closed switch of the relay KM5 is serially connected with the input end of the charging circuit (21), and the normally open switch of the relay KM5 is serially connected with the output end of the energy storage module (22).

8. An LED driver according to claim 1, wherein: an indicating component (27) is arranged in the standby circuit (2) in series, and the indicating component (27) comprises an indicating lamp.

9. An LED driver according to claim 1, wherein: the main circuit (1) further comprises a voltage stabilizing circuit (29), the voltage stabilizing circuit (29) is arranged at the rear end of the filter circuit (10) in parallel, and the LED load circuit (30) is connected with the output end of the voltage stabilizing circuit (29).

10. An LED driver according to claim 1, wherein: the front end of the main circuit (1) is provided with a voltage reduction circuit (30) in series.