There are 3 dimming methods for led fluorescent tubes
The dimmer for the brightness adjustment function of LED lighting fixtures is currently very important in LED lighting, and it is also a link that must be paid attention to at present, such as ED fixtures and display screens.
The following will introduce the relevant situation of LED tube dimming.
Type 1: Pulse Width Modulation (PWM). After adjustment, the driving current is in a square wave shape with variable pulse width. The pulse width is modulated to modulate the continuous lighting time of the LED tube, and the input power is also changed at the same time, so as to achieve the goal of energy saving and dimming. The frequency is about 200Hz~10KHz as usual; because of the hysteresis of human vision, the light source will not feel the sparkle phenomenon produced in the dimming process. It can improve the heat dissipation performance of the LED. The disadvantage is that the overshoot of the driving current will definitely have a certain impact on the life of the LED chip.
Type 2: Dimming of the LED tube is accomplished by modulating the LED driving current. Since the brightness of the LED chip is proportional to the LED driving current, we can control the brightness of the LED tube by adjusting the LED driving current.
The third type: imitating dimming method or linear dimming method. When the driving current increases or decreases linearly, the impact on the life of the LED chip during the overshoot of the driving current is reduced, and the dimming circuit has strong anti-disturbance. The disadvantage is that the change process of the drive current must have a certain influence on the color temperature of the LED chip.
