CN201967194U - Intelligent constant current LED light adjusting controller - Google Patents

Abstract

The utility model relates to an intelligent constant current LED dimming controller, which includes a dimming drive circuit, and the dimming drive circuit includes a power conversion module connected in sequence, a MUC microprocessor control module, an output dimming control module, and a MUC micro The processor control module is connected with a constant current control module, the input terminal of the output dimming control module is also connected with the output terminal of the PWM signal module, the output terminal of the constant current control module is connected with the constant current LED, and the constant current control module The control signal controls the output dimming control module to realize LED dimming. The dimming controller described in the utility model adopts a constant current driving mode, and the efficiency is more than 90%; it has high intelligence, can be controlled remotely, and is compatible with RS485 interface and DMX-512 interface; and uses a microcontroller to output PWM control signals to achieve PWM full digital dimming, so that the brightness of high-power LEDs can be dimmed in a full range, which can effectively save energy.

Description

An Intelligent Constant Current LED Dimming Controller

technical field

The utility model relates to the field of intelligent lighting, in particular to an intelligent constant current LED dimming controller.

Background technique

As a new type of high-efficiency solid-state light source, high-power LEDs have the characteristics of energy saving, environmental protection, long life, and small size. They are widely used in various indications, displays, decorations, backlights, general lighting, and urban night scenes. Unlike incandescent lamps, fluorescent lamps, and high-pressure sodium lamps that use high-voltage AC power sources, LEDs are driven by low-voltage DC voltage sources. Therefore, to ensure the best performance and long service life of LEDs, a stable and reliable drive circuit is required. In the prior art, the driving of LED lamps (such as guardrails, lamp cups, and projection lamps) mostly uses RC step-down plus a Zener diode for voltage stabilization, so that the power supply is suitable for supplying power to LEDs. Although this processing method is simple and Low cost, but there are many defects: 1. Due to the large energy consumption and low efficiency of the drop-down resistor, it cannot provide high current drive; 2. The ability to stabilize the voltage is extremely poor, which affects the brightness of the LED, and cannot guarantee that the current through the LED will not exceed its normal work requirements. Based on the technical problems existing in the traditional drive circuit, those skilled in the art propose two solutions: one is to change the voltage or current at the two terminals of the LED to achieve the purpose of dimming. From the analysis of the luminous characteristics of the LED, the voltage and current of the LED are not linear with the brightness. relationship, by adjusting the voltage and current, it is impossible to achieve a full range of 0-100% and average brightness adjustment, and often change the current and voltage of the LED, which will easily lead to shortened life of the LED; the other is to use PWM dimming, but because the LED The response time of the driver to the PWM dimming signal has a long delay, resulting in low dimming accuracy, so that the best dimming effect cannot be achieved.

Contents of the invention

The problem to be solved by the utility model is to provide an intelligent constant current LED dimming controller with high efficiency, stability and the ability to change the brightness from 0% to 100%.

According to the problems to be solved above, the technical solution adopted by the utility model is: provide an intelligent constant current LED dimming controller, including a dimming drive circuit, and the dimming drive circuit includes a power conversion module, a MUC micro Processor control module, output dimming control module, MUC microprocessor control module is connected with a constant current control module, the input end of the output dimming control module is also connected with the output end of the PWM signal module, the output end of the constant current control module is connected with the constant current control module The constant current control module controls the output dimming control module to realize LED dimming according to the control signal of the PWM signal module.

Specifically, the PWM signal is simulated and generated by a common IO port of the MUC microprocessor.

Specifically, the constant current control module includes an integrated chip with a constant current output, the integrated chip has a built-in field effect transistor, the chip has a DIM terminal, a GND terminal, a VIN terminal, and a CS terminal, and its PWMD terminal is connected to the PWM signal module , the VIN terminal is connected to the power supply circuit through a diode, and the built-in field effect transistor is connected to the inductor through SW; the CS terminal of the integrated chip is grounded through a parallel resistor.

Preferred: the LED dimming controller further includes a signal connection with the MUC microprocessor circuit for receiving remote control commands, and then controls the dimming drive circuit through the MUC microprocessor to realize the bus communication circuit for LED dimming; the described MUC microprocessor dimming signals are all generated by ordinary IO port modules; the communication circuit is compatible with RS485 interface and DMX512 interface, which is used to receive control commands from other controllers, and then realize intelligent control dimming.

Compared with the prior art, the utility model has the beneficial effects of:

(1) The utility model adopts a constant current drive mode, and the efficiency is more than 90%;

(2) The utility model has high intelligence, can be remotely controlled, is compatible with RS485 interface and DMX-512 interface, and can flexibly realize point control, group control, time control, scene control, sensor automatic control and computer centralized control through bus control ;

(3) The utility model adopts MUC microprocessor to output PWM control signal to realize PWM full-digital dimming, and then make high-power LED brightness dimming in the full range (0%~100%), which can effectively save energy;

(4) The single-channel drive capability of the utility model is strong, which avoids the disadvantages of troublesome wiring, large wire consumption and heavy pollution of traditional wiring.

Description of drawings

Fig. 1 is a schematic block diagram of the utility model principle;

Fig. 2 is a schematic diagram of the circuit principle of the utility model embodiment;

Fig. 3 is a schematic diagram of the bus communication circuit of the utility model.

Detailed ways

In order to facilitate the understanding of those skilled in the art, the utility model is described in further detail below in conjunction with the accompanying drawings:

The schematic block diagram of the principle composition of the dimming controller as shown in Fig. 1 . An intelligent constant current LED dimming controller, including a dimming drive circuit, the dimming drive circuit includes a power conversion module connected in sequence, a MUC microprocessor control module, an output dimming control module, and a MUC microprocessor control module A constant current control module is connected, the input terminal of the output dimming control module is also connected to the output terminal of the PWM signal module, the output terminal of the constant current control module is connected to the constant current LED, and the constant current control module controls the output according to the control signal of the PWM signal module. The dimming control module realizes LED dimming.

The utility model embodiment circuit principle diagram is as shown in Figure 2. The DC power supply is output to the voltage stabilizing circuit after being rectified and filtered by capacitors C4, C5, and C10. The voltage stabilizing circuit is mainly composed of a power supply integrated chip U5 (LM2575HV-5.0). To the microprocessor and the corresponding chip.

The integrated chip U3 and corresponding peripheral circuits form a constant current control module. The constant current control module includes an integrated chip with constant current output. The integrated chip has a built-in field effect transistor. The chip has a PWMD terminal, a GND terminal, and a VIN terminal. , CS end, the PWMD end of which is connected to the PWM signal module, the VIN end is connected to the power supply circuit through a diode, and the built-in field effect transistor is connected to the inductor L1 through SW; the CS end of the integrated chip is grounded through a parallel resistor.

The utility model can include a multi-channel dimming driving circuit, which can respectively form multi-channel dimming by connecting with a plurality of I/O ports of the MUC micro-controller.

When the utility model works, the control chip U3 outputs a constant current signal to control the switch of the internal MOS tube by sampling the signal at the DIM terminal. When the MOS tube is turned on, the current flows from the power supply through the LED lamp, the inductor L1, and the sampling resistor R8 to the ground. When the current in the inductor L1 continues to increase, the voltage of the CS terminal of the chip U2 also continuously increases. When the CS voltage is higher than 240mV, the internal control circuit of U1 turns off the GD terminal, and the MOS tube is turned off. Since the polarity of the current in the inductor L1 cannot change abruptly, the current will flow from the power supply to the power supply through the LED lamp, the inductor L1, and the freewheeling diode D3. After that, the current in the inductor L1 keeps decreasing until the next oscillation cycle comes. This repeated action, the current in the inductor L1 is repeated from the minimum value to the maximum value and then to the minimum value. Since the LED lamp is connected in series with the inductor, the current on the LED lamp is equal to the average current of the inductor. Different average currents make the LED lamp emit light. Different brightness of light, to achieve LED dimming.

Fig. 3 is a principle schematic diagram of an embodiment of the bus communication circuit of the present invention. In the figure, U1 is a communication chip. Pins 1 and 4 of U1 are connected to the MUC microprocessor circuit. The communication chips 485A and 485B receive remote control signals and transmit them to the MUC microprocessor, which is decoded and controlled by the MUC microprocessor to output dimming control modules. Dimming. The bus communication circuit is compatible with RS485 interface and DMX512 interface.

The above embodiments are only the preferred implementation of the utility model, and can not be used to limit the utility model. Under the premise of not falling off the concept of the utility model, any equivalent replacement and minor changes made to it belong to the utility model scope of protection.

Claims (6)

1. intelligent constant-current LED light adjusting controller, comprise the light modulation drive circuit, described light modulation drive circuit comprises power transfer module, MUC microprocessor control module, the output dimming controlling module that connects successively, MUC microprocessor control module is connected with the constant current control module, it is characterized in that: described output dimming controlling module input also is connected with pwm signal module output, constant current control module output is connected with constant-current type LED, and the constant current control module realizes the LED light modulation according to the control signal control output dimming controlling module of pwm signal module.

2. intelligent constant-current LED light adjusting controller according to claim 1 is characterized in that: described pwm signal module adopts the MUC microprocessor to produce.

3. intelligent constant-current LED light adjusting controller according to claim 1 and 2, it is characterized in that: described LED light adjusting controller further comprises being connected with MUC microprocessor control module signal and is used for the receiving remote control command, and then realizes the bus communication circuit of LED light modulation by MUC microprocessor control module control light modulation drive circuit.

4. intelligent constant-current LED light adjusting controller according to claim 4 is characterized in that: described bus communication circuit compatibility RS485 interface and DMX512 interface.

5. intelligent constant-current LED light adjusting controller according to claim 1 is characterized in that: described constant current control module comprises integrated chip U3, and described U3 PWMD end connects the pwm signal module, and U3 connects inductance L 1 by the CS utmost point.

6. intelligent constant-current LED light adjusting controller according to claim 4 is characterized in that: described integrated chip U3 CS end is by parallel resistor R8 ground connection.

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