If you’ve gone down the lighting isle of a store recently, you’ve no doubt noticed we are firmly in the age of the LED light bulb. Incandescent bulbs are kept in small stock for those who still have the odd-ball use case, there’s usually a handful of CFL bulbs for those who don’t mind filling their house with explosive vials of hot mercury, but mostly its all LED now. Which is as it should be: LED lighting is clearly the superior choice in terms of energy efficiency, lifetime, and environmental impact.
Unfortunately, a lot of the LED bulbs you’ll see on the rack are of pretty poor quality. In an effort to drive cost down corners get cut, and bulbs which should run for decades end up blowing after a couple of months. After yet another one failed on him, [Kerry Wong] decided to do a teardown to examine the failure in detail.
He notes that most of the LEDs seem to fail in the same way, flickering after they are switched on until they just stop lighting up entirely. This hints at an overheating issue, and [Kerry] opines that aesthetic and cost considerations have pushed heat dissipation to the back burner in terms of design. It also doesn’t help that many of these bulbs are sitting in insulated recessed fixtures in the ceiling, making it even harder to keep them cool.
Once he separates the actual LEDs from the driver circuitry, he is able to determine that the emitters themselves still work fine. Rather than toss the whole thing in the trash, it’s possible to reuse the LEDs with a new power source, which is quickly demonstrated by showing off a shop light he built from “dead” LED light bulbs.