Why should the lamp dimming? Said: by dimming can be in the light to get a more comfortable environment, but also to achieve energy saving. LED dimming how to achieve? Said: LED dimming There are two ways of thinking three ways: the idea of a linear analog to adjust the LED current; thinking two PWM digital dimming, is to use the switch circuit relative to the human eye recognition Work high enough to change the average of the light output.
1: linear dimming, that is, by adjusting the size of the LED forward current dimming, this method is more original one.
Change the size of the current through the LED to change the brightness of the LED, LED output output relative to the light intensity and the relationship between the forward current is almost linear. Figure 1. In the lighting circuit by a variable resistor dimming. The application is very simple, it will not produce interference, but the principle of partial pressure is to make electricity is not entirely used in lighting (electrical), no efficiency at all. Dimming the light, the dimming resistance due to excessive pressure and produce a lot of heat, resulting in waste of energy and environmental degradation
2. Analog dimming: that is, thyristor dimming, compared to the traditional analog dimming method.
Common analog dimming with bidirectional thyristor dimming, trailing dimming, ON OFF dimming, remote dimming and so on. SCR dimmers in the traditional incandescent and other dimming lighting applications for a long time, and do not change the wiring, the device cost is low, the brand of thyristor dimmer performance and specifications of little difference, but its direct application LED drive occasions there are still a series of problems.