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Flashing LEDs - Quick Question Answered

Just Curious - does programming led lights to flash cause their lifespan do be shortened?

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Kiteman (author)2007-07-09

If you just want an LED to flash, and you're not bothered about the specific frequency it flash at, why not just buy a flashing LED?

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NachoMahma (author)2007-07-09

. I'll _guess_ that flashing any electrical device will shorten its' life. . Given the expected life of LEDs (6K+ hours), I can't imagine it being a big deal in the real world.

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stasterisk (author)2007-07-09

Actually, if you compare the lifespan of an LED you turned on solid, to one you flash, the flashing one may have a longer lifespan - the flashing LED gets to cool off, some, compared to the solid-on LED, and it will take you much longer to pass the same amount of energy through the flashing one (whatever your duty cycle is) than through the solid. A 555 timer is pretty easy to set up, consider the resistors and capacitors your "configuration settings" for the 555 - the different values you choose govern the rate at which the 555 spits out pulses, and therefore the rate at which your LED flashes. Note: "flashing" doesn't necessarily mean the amount of time the LED is on is the same as the amount of time the LED is off! This is why it's important to pay attention to what you put on the 555. And, don't get confused by the internet. 555 documentation can get deep, but this is a pretty easy (read: plug together radio shack parts) thing to do.

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stasterisk (author)stasterisk2007-07-09

You might also be just fine picking up a 555 at radio shack and reading the little diagram on the back.

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stasterisk (author)stasterisk2007-07-09

Also, if the LED is going to be extra-bright, you might want to just throw in a transistor between the output pin of the 555, and the LED, to give more current to the LED.

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LasVegas (author)2007-07-08
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Joe426 (author)LasVegas2007-07-08

Thanks. whats the best microcontroller to use to program led lights to flash?

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LasVegas (author)Joe4262007-07-08

Is there a specific flash sequence you want to execute or do you just want it to flash? If all you want is a flashing LED, use a simple 555 flash circuit. One chip, a capacitor and a couple of resistors is all you need.

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Joe426 (author)LasVegas2007-07-09

I just want it to flash. So...Sorry, im a complete noob at this - how do i set up a 555 circuit? why wud i need a capacitor?? thanks!

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LasVegas (author)Joe4262007-07-09

Do a Google search for lm555 datasheet and study the sample schematics. A flash circuit is about the most basic use of the chip. You can also find various kits around the net for the layman.

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Joe426 (author)2007-07-08

whats the best microcontroller to use to program led lights to flash?

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