LED drivers
Time:2008-12-13 22:31:32 Click:Load...
LED drivers
LED chips require controlled direct current (DC) electrical power and an appropriate circuit as an LED driver is required to convert the alternating current from the power supply to the regulated voltage direct current used by the LEDs.
LED drivers are the essential components of LED lamps or luminaries. A good LED driver can guarantee a long life for an LED system and provide additional features such as dimming and control. The LED drivers can be put inside the lamp or luminaire, which is called a built-in type (or integral), or be put outside, which is called an independent type (or remote). According to different applications, different types of LED drivers need to be applied; for example, an outdoor driver for street light, an indoor point driver for a down light, and an indoor linear driver for a panel light.
Research studies such as analyse the power quality indicators correlated with the provided lighting outputs, under different voltage values and wave-forms. The harmonic limit check performed in line with class C–lighting equipment, IEC 61000-3-2 requirements is evaluated for different LED setups.
Thermal management
Compared to other lighting systems LEDs must be kept cool as high temperatures can cause premature failure and reduced light output. Thermal management of high-power LEDs is required to keep the junction temperature close to ambient temperature. LED lamps typically include heat dissipation elements such as heat sinks and cooling fins and very high power lamps for industrial uses are frequently equipped with cooling fans.
