Analyze the dimming method of LED downlight
- Jun 13, 2018 -

All of the LED downlights are popular among consumers because it not only has a long life, but also has a high power. The more important thing is that it also meets the needs of the entire shopping mall and has the characteristics of energy saving and environmental protection. Another point worth mentioning is that LED downlights can dim, that is, according to the conditions of light and dark scheduling of light and brightness, it is not only more humane, but also the best expression of energy saving.

There are three kinds of dimming methods for LED downlights, which are often the most common ones. These three kinds of dimming techniques are all based on the LED drive current input changes to adjust the light. According to different circuit systems can also be divided into analog dimming and PWM dimming.

The first one: This dimming method is to finish the dimming of the LED downlight by modulating the LED drive current. Since the brightness of the LED chip and the LED drive current become a certain share, we can control the LED drive by scheduling the LED drive current. The brightness of the light.

Second: This dimming method is called an imitation dimming method or a linear dimming method. The advantage of this kind of dimming method is that when the drive current linearly increases or decreases, the influence of the overshoot on the driving current over the lifetime of the LED downlight is reduced, and the anti-interference of the dimming circuit is strong. The disadvantage is that the process of changing the size of the drive current must have a certain influence on the color temperature of the LED chip.

Third: This dimming method is called pulse width modulation (PWM). In this method, the drive current is square wave shaped through a schedule, the pulse width thereof is variable, and the time for modulating the LED downlight to be continuously lighted is changed by modulating the pulse width, and the input power is also changed, and then the energy saving and dimming are reached. intention of.

The frequency is about the same as usual at 200Hz~10KHz; due to the hysteresis of the human eye vision, it will not feel that the light source is flickering during the dimming process. The advantage of this dimming method is that it can improve the heat dissipation function of the LED. The disadvantage is that the overshoot of the driving current must have a certain influence on the life of the LED chip.

LED dimming is one of the most important characteristics of its dimming function. Its fully automatic adaptive universal dimming is unfinished by any other luminaires, and is therefore one of the key development trends in the future.