The intelligent dimming technology of LED spotlights

Perfect intelligent control should have a manual control, intelligent control, light control, time control and fault alarming system. When the sun goes down, the lamp should automatically light, and at midnight, it can be automatically reduced by half; after dawn, the light automatically turns off; in special circumstances, it can be manually control; if control fails, the control system can automatically alarm. There are three main methods for these dimming technology.

The first method is by adjusting the LED drive current to achieve dimming LED lamp, because the brightness of LED chips and LED drive current have a fixed proportion.

The second method is often called the analog dimming mode or linear dimming. The advantage of this dimming is: When the drive current linearly increases or decreases, it will relatively lower the effect of LED chip’s controlling circuit strong immunity to the drive current overshoot. The disadvantage is that it will have an impact on the color temperature of the LED chip, when the driving current changes.

The third way is dimming pulse light modulator (PWM) mode. This method is through certain controlling, to make the drive current square, has variable pulse width, to change the duration time, and the output power at the same time, so as to save energy. When its frequency is 200Hz to 10kHz, due to the human eye visual retention, people typically may not feel the process of light blinking and light moving. The advantage of this method is that it can improve the heat dissipation. The disadvantage is that the drive current overshoot will effect the life of the LED chip.

These three dimming method is classified based on the controlling output of the LED drive current. The control circuit may also be divided into analog control and PWM control, the control circuit is usually done by the microcontroller.