Hey everyone I have a hobby for making electronic things but have know education in the area.
I want to take on a more seriouse project soon which involves 2 really bright leds , a switch and a 9 volt battery.
Can you tell me what type of leds specs I need to look for when buying? I prefer the colours blue or green.....I need them to be bright because this circut will be on my bike and at night I want it to really stand out.
what is mcd?
viewing angle?
how do I make the led not burn out because of 9 volt battery , can leds handle 9 volt batteries?
Please help and explain in detail
not know, no*
From a 9V source, you can run just about any sort of LED. The blue ones are usually rated for about 3.5V-4.5V or so, while green, yellow, and red are typically more like 1.7-2.1V. White LEDs also exist... sort of. They're usually blue LEDs with a yellow filter, which simulates white.
The LED works like a voltage reference... when you put a current through it, it wants to go to a voltage specific to that LED. In order to prevent the LED from basically fighting against the voltage applied, you need to put a resistor in series with the LED. This will also effectively set the current for the system. More on that in a bit.
MCD = millicandelas... it's a rating of brightness. One candela is supposedly the brightness of one standardized candle, one MCD is 1/1000th the brightness of a candle. Viewing angle is basically indicating the spread of the LED. Most LEDs have lenses molded into their housings,,, the light can be tightly focused, or spread wide.
To ensure you don't damage the LED, you'll need to add a resistor, as mentioned. You'll need to do a little mathematics to calculate just what value, but it's pretty easy. Measure current in Amps or Milliamps (1/1000th of an amp), voltage in volts, and the resistor value in ohms. Ohms law states for any circuit, E = I * R (voltage (volts) = current (amps) * resistance (ohms)).
So, you have a 9V battery. Let's assume you got the 2600mcd blue LED from Radio Shack (p/n 276-316). That LEDs would like 3.7V to 4.5V to it, and it can take a maximum current of 20mA (0.02A). So worst case, you are dropping 5.3V at 20mA in the resistor, 5.3V / 0.02A = 265 ohms. Radio shack sells a 330 ohm resistor, 271-1315, which will work.
Keep in mind that an LED, being a diode, is a polarized device... it only turns on when the anode is connected to + and the cathode to -... this should be indicated on the package. The resistor can go on the anode or cathode, it doesn't matter.
If you want more than one LED, you can actually put two in series from the +9V battery, though you'll need a much smaller resistor. I found a web page that illustrates some of this: http://www.kpsec.freeuk.com/components/led.htm
Whats On My YouTube Today?
Three color LED electronic message center LED signs!
Here Are A Few Items From Amazon You Might Be Interested In.
Account limit of 2212 requests per hour exceeded.
Items recently purchased on this site:
New White "Love Is the Drug" Style DIY Wall Art PVC Stickers Home Decal Mural, New Orange DoDo Fish Shaped Home Decor Mural DIY Wall PVC Art Stickers, New Reed Flowers DIY Wall Art Stickers PVC Home Decal Mural Black, New Small African Daisy DIY Wall Art PVC Stickers Black Home Decal Mural, New "Have A Nice Day" Style Home Decor Mural DIY Wall Art PVC Stickers, Areaware Numbers LED Alarm Clock Black with Red Numbers OE66AC, New Fashion White Reed Flowers DIY Wall Decor Art PVC Stickers Decals, Charm Child Kids love Tiger Bear DIY Wall Home Mural Decal Sticker PVC Stickers, New Butterfly Flower & Fence DIY Wall Art Sticker Home Decal Mural PVC Paper, 36" Wall Mount Electric Fireplace Heater Tempered Curved Glass Back Light 520APB, New "Simple Life" Design Home Decor Mural DIY Wall Sticker PVC Art Stickers, New Rose Flower Style DIY Wall Art Sticker Home Decor Mural PVC Stickers, New Rose Red "Love Is the Drug" DIY Wall Art Sticker home Decor Mural Stickers, NEW Grey "Happy Mail Box" Style DIY Home Decor Mural Wall PVC Art Stickers, New "Love and Be Loved" Home Decor Decal Mural DIY Wall PVC Art Stickers, New Charm Bear Measuring Height DIY Wall PVC Stickers Home Mural Children's Room, New Time Memory Black Photo Style Home DIY Wall Art Stickers, NEW "Happy Time" DIY Home Decals Mural wall PVC Art Sticker Stickers, New Giraffe Height DIY Wall stickers Children Baby Kid Room Home Decal Mural, New Green Tree Photo Posted DIY Art Wall Stickers left Home Decal Mural, New Coffee Reed Flowers Style Home Decals Mural DIY Wall PVC Stickers, New Fashion "Time Memory" Style DIY Wall Art Home Decal Mural PVC Stickers Gray, New Black Music Note DIY Wall Art PVC Stickers Home Decor Mural, 36-inch Wall Mount Modern Electric Fireplace Heater LED Remote Control 510E-PB, Home Office Magnetic DIY Door Stopper Stop Holder Catch Doorstop + Screw, Green Animal Style Child Baby Safety Helper Door stop Stopper Finger Protector, NEW Multi-function Hook Hat/Tie/Jewelry Flocking Pothook Useful, New Child Baby Room DIY Wall Art Stickers Jungle Train Home Decal Decor Mural, New Fashion Colors Butterfly Design Art DIY Wall PVC Stickers Home Sticker, New "Life Is A Journey" Style Home Decor Mural DIY Wall Sticker Art Stickers, New Black Flower Elves Design DIY Wall Art PVC Stickers home Decor Mural, New Birds & Branch Style DIY Wall Art Sticker Home Decor Mural PVC Stickers, New Lovely White Love Is the Drug DIY Wall PVC Stickers Home Decor Mural, New Orange DoDo-Fish Home Decal Decor Mural DIY Wall Art PVC Sticker Stickers, New Fashion "Have A Nice Day" Home Decal Mural DIY Wall Art PVC Stickers, New Bicycle & Tree DIY Art Wall Sticker Home Decor Mural PVC Stickers, New Small African Daisy DIY Wall Stickers PVC Black Home Decor Mural, New Snowflake Child Kid's Room DIY Wall Art Stickers Vinyl Home Decor Mural, New Reed Flowers Design White DIY Wall Art PVC Stickers, New Colorful Butterfly Flower & Fence Design DIY Wall Art PVC Stickers, NEW "Happy Mail Box" grey DIY Home Decor Decal Mural Wall PVC Stickers, Compact 9.8"-11" Invisible Plate Hanger Polished Decorating Porch Wall holding , New Reed Flowers Style DIY Wall Stickers PVC Home Decor Mural Black , New "Time Memory" Style DIY Wall Art Sticker Home Decal Mural PVC Stickers Gray, New "Love and Be Loved" Style Home Decor Mural DIY Wall PVC Stickers, New Small Orange African Daisy Home Decor Mural DIY Wall Art PVC Stickers, New "Time Memory" Black Photo Frame Design DIY Wall Art Vinyl Stickers, New "Time Memory" DIY Wall Art Sticker Home Decor Mural Brown PVC Stickers, New Cartoon Sunflower DIY Wall Stickers Baby Child Kid's Room Home Decor Mural, New "Simple Life" Home Decal Mural DIY Wall Sticker PVC Art Stickers, Charm "Life is a Journey" Coffee DIY Home Decal Mural Art Wall PVC Sticker, New Green Tree Style Photo Posted DIY Art Wall Stickers left Home Decor Mural, New Child Baby Room Jungle Train Style DIY Wall Art Stickers Home Decor Mural, New Black Flower Elves Styel DIY Wall Art Sticker PVC Stickers, New 7 Color Flicking LED Change flameless lights Bulb Candle Tea Light Candles, New Bicycle Tree Style DIY Art Wall Stickers Home Decor Mural, New Giraffe Style Height DIY Wall stickers Children Baby Room Home Decor Mural, Green Child Baby Kid Safety Helper Door stop Guard Lock Stopper Finger Protector, New Zinc Alloy Magnetic DIY Door Stopper Stop Holder Catch Doorstop + Screw, New Colorful Butterfly Art DIY Wall Sticker PVC Stickers,
This entry was posted on
Tuesday, December 14th, 2010 at
3:35 pm and is filed under
home decor . You can follow any responses to this entry through the
RSS 2.0 feed.
Responses are currently closed, but you can trackback from your own site.
