Depending on the application, LEDs can be connected in series and parallel configurations. Obviously, when LEDs are connected in series the forward voltage drop of each LED in the string are additive.

For example, if you put 15 LEDs in series and each one has a voltage drop of 3V (at its nominal current), you need to provide a voltage source of 45 V (15 x 3 V = 45 V) to drive the required current. This is why constant-current drivers always include in their specs the output voltage range that it is capable of providing to overcome the LED voltage drops. In order to limit the drive voltage to reasonable levels, multiple strings of series-connected LEDs can be placed in parallel and driven by multi-output constant-current drivers.

Triac Dimmable LED Driver	Dali Dimmable LED Driver	0-10V Dimmable LED Driver
12v/24Vdc 12W	12v/24Vdc 60W	12v/24Vdc 120W

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