Common method of dimming LED lamps
LED lighting dimming methods are the most important three: these three skills are based on the current dimming input changes for dimming. In accordance with the different circuit system, it can be divided into imitation dimming PWM dimming.
The first: This dimming method is by modulating the LED drive current to complete LED lighting dimmer, because the brightness and the LED drive current have a certain proportion of stakeholders, so we can adjust the LED drive current to control LED lighting light and shade.
The second: This method is called imitating the dimming method or linear dimming method. This kind of dimming method has the advantage: When the current linear growth or decreases, they are reducing the drive current overshoot during the life of the LED chip and tune Lu strong anti- nuisance. The defects are the size of the change process of the drive current of the LED chip certainly has certain impact.
The Third: This dimming method is called pulse width modulation (PWM). The method is by adjusting the driving current, and let it be square wave. The pulse width is variable, through the pulse width modulation into a modulation of the continuous light LED lighting time, and also changes the input power, so as to achieve dimming target. Frequency as usual is at about 200Hz ~ 10KHz; Because the human eye visual lag, who will not be felt in the dimming light generated in the process shine phenomenon. Such dimming method has the advantage of improving the thermal performance of LED, the defect is driving current overshoot the life of the LED chips certainly have some impact.