LED power consumption

[edhesketh]

Does a simple LED light use up more power when it is flashing or when it is on continuously?

[Ant]

I don't really know the answer in terms of LED power consumption, and I did really bad in electronics at school, but I would imagine that if some circuit is used to make the LED flash then it would consume more power. Yet if the LED flashes without the external circuitry i'm guessing the power used up between either a flashing LED or normal LED is so minimal that you'd have to test it in a lab to figure it out. I'd say there isn't much of a difference.

[tomr]

It uses more power when it is on continuously because when it is flashing it is off when it isn't on.

Nomimal forward current for a single LED is about 10 - 20mA, they have a forward volt drop of 1.5v so the dissipated power is in the order of 20mW. Modulate it on and off for equal periods and the overall power will be half, if you modulated it in excess of 50Hz you would barely tell it was flashing (LED ticker signs only have one LED illuminated at a time) and you would perceive a drop in intensity in proportion to the ratio of on to off.

It would be a very poor flasher circuit that consumed more power than the LED itself.