radishj

如果你不是用电池做电源，是需要的。
I like the following explainations.

Think of an LED driver as ‘Cruise Control’ (like in a car) for the LED, and the temperature changes of the LED are the hills and valleys it is ‘driving’ over. The power level (or ‘Speed’) of the LED is maintained constant by the driver as the electrical properties change (amount of ‘gas’ or power needed) throughout the temperature increases and decreases (or ‘hills and valleys’) seen by the LED(s). Without the proper driver, the LED may become too hot (driving too fast) and become unstabe (out of control), causing poor performance (engine problems) or complete failure (crash!)