How come LED Light Bulbs only last for about 2-3 Years?
How come LED Light Bulbs only last for about 2-3 Years?
I've bought and replaced a lot of light bulbs, and I noticed that all of them said "up to 20,000 hours" which would be about 5 years given 12 hours of daily use (which we definitely don't).
I have been dumpster-diving for LED bulbs for 5 years. None of them had 200 chips, they usually have about 5-30 packages with 1-6 diodes each for a total of around 30-60 so that they total some 90-180 V in series (I live in a 230V mains region, and the 330V rectified mains can be efficiently transformed to that voltage by an SMPS). Because they are in series, if one in the series chain fails open circuit (the most common way), the entire chain goes out. Yes, fixtures (not bulbs) with 100+ LED chips exist and if they are designed to operate at a low voltage with all chips in parallel, the failure of one will not affect the others.
I saw Big Clive and DiodeGoneWild take some apart, and we had been using halogen or fluorescent ones at home because LED bulbs were over $10 back then. I thought I would learn something about electronics but not really, the failure modes are always the same: about 50% of the time, an LED burns out. 25% of the time, it's the smoothing inductor gone open circuit. 10% of the time, a bad contact somewhere (usually solder joints on linearly-regulated ones). 5 % work out of the box for some reason. I remain adamant about not paying for LEDs even though dumpster diving is objectively not worth the trouble anymore.