Flickering LEDs are everywhere. I can think of a number of reasons why an LED might flicker:
- Supplied from an AC outlet (traffic lights in ex-USSR)
- Addressed one chunk at a time (most multi-position 7-segment displays, for example)
- Fading (dimming)
But some occurrences have me stumped. In particular, the LED-based stop lights on some cars. I can see no reason for these to flicker: they are supplied with DC, and they are either entirely ON or entirely OFF, so no addressing issues and no dimming. And yet they flicker.
Is there some reason why someone would intentionally make LEDs flicker in such circumstances? Perhaps one can get more light per watt out of them this way or something like that?
Best Answer
On automobiles, the same LEDs are used for both taillights and brakelights. When braking, they're on full — no flickering — but when they're just taillights, they're dimmed, so they flicker. Very annoying.