I was thinking of a topic to post today, and I thought I'd bring out the nerd in me to talk about LEDs in the subject of Electronics.
I remember when LED were first introduced, they were like this :
Then they managed to miniaturise them as well as achieving High Brightness with them.
Many touted LEDs as longer lasting lights for the home, ie. no more changing of light bulbs. And cheaper running cost for electricity.
However, I can tell you most people have experienced LED lights failure very often. Why is this so ?
There are many reasons :
The many LEDs elections in the bulb are usually run in series (one connected to the other). So if just ONE diode is burnt, the entire bulb will be dead (open circuit) and no light from the bulb.
The LEDs are run are maximum possible wattage for more light. This in turn creates heat which if not dissipated enough, will shorten the life-span of the LEDs as well as the power circuit that powers them. Usually the failure rate of the power circuitry (driver), is far higher than the LEDs failure rate.
So why dont manufacturers make more efficient LED lights where the following attributes :
a. Lower power dissipation - low power consumption
b. Longer Life span
The answer is PROFITs of course. Producing a highly efficient light bulb will mean people will not change a light bulb for years or decades. Cost of making a bulb would possibly be higher.
Philips has actually developed something like that. But solely available only in the middle east... called the Dubai Lamp...
Sadly, it is not available anywhere else in the world yet.
How they achieve it is to introduce more filament in the light bulb and not driving each to the maximum... by driving each at a voltage/current that is at the LEDs most efficient range... they output optimal light at minimum heat dissipation. This also help the power driving circuit..
For those of you who want to learn more about such bulbs, look at the following youtube video with a teardown and reverse-engineering