Home Depot is now selling a $20 EcoSmart LED bulb — it’s dimmable, even! Margery Conner, of Electronics Design News, got one and went medieval on it to figure out what makes it tick — or in this case, glow.
I love this process of deconstructing a piece of hardware, looking up the datasheets for the components, figuring out the strengths and weaknesses of the design, etc. Here’s a bit of what she learned:
Not the usual intense light sources we’ve seen in other LED lights: These are large surface-area LEDs that make for a very pleasant diffuse light source. And the light only requires two of them to put out 429 lumens at 8.6W.
Well, I couldn’t find a manufacturer’s label, but there is an apparent part number; AM6L1, and the part looks like an LED array, meaning that, rather than a single emitter, the LED packages up several tiny LED chips in one package and covers them with a single phosphor. It’s a good choice to use such a diffused light source – no pixilation.
The e-cap (just partially visible to the right) is potential weak link and this design uses a good-quality part. Compared to other LED lights, this one has relatively little hand-soldering. As we know from Geoff Potter’s research, solder joints are the Achilles’ heel of LED lighting reliability. Going with a highly-integrated LED driver part like the LM3445 in itself gets rid of a lot of solder joints.
If you enjoy these sorts of teardown investigations, stay tuned…. We have a contest coming up to challenge you to peer under the hood of some of your gadgets and tell us what you discover. [Thanks, Tim Slagle!]