In upgrading a older home, and trying to keep it energy efficient, I've used several LED lamps. In a high chandelier I've got "early adopter" candelabra flame lamps by Lights of America. Lamp has eighteen or so single LEDs pointing up soldered to circular PC boards. One third of them failed--all LEDs quit so failure is in wiring or passive/active driver circuitry. In other apps I've found the best approach is actually a combination of two or all three sources: incandescent, CFL, LED. LEDs alone too harsh a color and too costly, CFLs poor CRI and slow warm-up, incands inefficient and no color variation and color change with dimming.
There will always be a place for a 60W incand up in a closet, for example. The worst part of the current state of lighting is the govt telling us what to use and not use. Lamp choice should always be a market driven and personal decision. Subsidies represent stealing from Peter to pay Paul.
LED lamps, particularly as used in automotive/military applications, are invaluable - and, no EMI problems! LED lamps for residential use will be standard very soon. If one has a problem with EMI from an LED lamp then that lamp is a very poor design or the wiring/socket is problematic. Oh, I routinely use CFL and regular white LED's for lighting in my home office - the color temperature is just fine; in fact, it matches my PC monitor!
I have one of those Home Depot A-bulb LED lamps. The color rendering is not great, but tolerable. What is horrible is the RFI - which knocks out even local FM stations on my nearby radio. Yecccch! Banished that sucker to a closet where it spends most of its time off.
Why the CREE can clamp the efficiency and power and even cost without mentioning the electronics to drive the LED? I don't think the LED is a real AC LED that can just plug in to the wall without any electronics to convert the power and voltage. So, even though the LED itself won't eat up too much electrical power and generate good enough lumens, it also has to count in the related LED driver for overall efficiency and of course this LED driver will add cost. More to say is that the lifetimes of most LED lighting nowadays are much shorter than what they claim! Why is that so? I believe one of the cause it the low cost and poor electronics that drive it! So this makes the equation more complex when we consider the advantage of LED lighting. So, in future it would be good to also consider what LED driver topology is the best to drive LED, both with robustness and efficiency.
Yes - if competently designed. It is harder to make a power LED to last for this order of time than it is to make matching power electronics. Any company able to handel the LED challenge 9Osram, Cree, Philips, Seoul, Agilent, Nichia, more ...) will easily be able to provide electronics that matches.
Brand and available technology is what counts.
Most of the top LED makers manufacture in China. If you bu\y from a reputable company the company of manufacture is irrelevant. That said - there are MANY bad LEDs available - many are chinese made. Due diligence is required to ensure they have access to capable technology.
Blog Doing Math in FPGAs Tom Burke 24 comments For a recent project, I explored doing "real" (that is, non-integer) math on a Spartan 3 FPGA. FPGAs, by their nature, do integer math. That is, there's no floating-point ...