I'm planning on getting one of these LEDs for my car. Since it's for my car it's being wired into a 12v source. What resistor would I need for it to work?

It will be wired to my interior lights so it turns on with the dome light. Their back will be pulled tight against a plastic molded compartment in my dash. The light shouldn't get too hot right? And the website says "Intensity MCD (typical): 600 mlm" That doesn't seem right, is it? They have a 10mm LED that is 28,500mcd. I would get that but it only has a 10˚ viewing angle.

LED Page:
http://www.radioshack.com/product/index.jsp?productId=3060973

Resistor Page:
http://www.radioshack.com/family/index.jsp?s=A-StorePrice-RSK&x=10&y=7&categoryId=2032267&pg=1&searchSort=TRUE&retainProdsInSession=1

Thanks!

Yeah, I found a site pretty close to that before I posted. I try to find my own answer before I ask.

I don't know how to fill in the chart. I know supply voltage, 12V, but the other's I'm not sure of.

Supply Voltage
12V
Voltage Drop Across LED
3.5V?
Desired LED Current
20mA?
How many LEDs Connected
1

That gives me:
Exact calculated resistance = 425OHMS
Nearest higher rated resistor = 470OHMS
Wattage recommended for resistor = 1/4W

It also gives this picture:


Does that mean that I'm looking for this?
http://www.radioshack.com/product/index.jsp?productId=2062342

Also, I just noticed that the LED i picked out has four pins. Does it still get wired the same as a regular 2 pin LED, with just two wires, one on each side?

This seems about right. As for the four pin led, did you pick it up from RS? Is it a dual color led, or a blinking led? In this case, you'd probably wire to both positives (along with your resistors) and then to the negatives.

If you don't mind waiting for shipping from HK go to ebay and look for BestHongKong that's where I get my led's from. Usually 50 for less than 10 shipped. And they give you resistor's too.

Sorry I didn't read this post right. No you only wire up two pins. Its not a dual element led. What are you using this for?

Thanks for the eBay link. They don't have any items for sale right now tho. I checked their website and the leds I was interested in were a little too much for my piggy bank right now. But srsly, I'll keep them in mind for future projects.

I'm probably going to go to RS tonight and buy them after class, and after the people from my apartment come and fix meh oven.

I'm putting it in a little cubby hole in my dash just below my radio. It's about 4" deep, 1.5" tall, 2.5" wide. So I need something with a very wide angle and preferably as short as possible. It will be mounted on the roof of the cubby. God I hate the word cubby.

Oh so you just need some light in there. I have some prewird white ones ill sell ya cheap.

Thanks, but I just got back from "The Shack". That's what they're apparently calling themselves in the store now.

How do I know which side is positive and which is negative? Also the resistor should go on the positive side right?

In this picture is the positive on the left side (the side where the pins go up and are obviously connected to the diode) or the right side (the side where the pins go up and look like they're not connected to the diode)?

Got it all wired up. It seems like the LED is quite dim tho. I used one 470Ω resistor wired to the positive side. It's not the power source because I replaced all of the lights inside my car with LEDs so I have a lot more free power than I did with the stock halogen bulbs.







I'll prolly edit with a night shot later tonight. It ended up costing just over $8 but I have quite a few extra parts now. I'm about 8/10 happy. I would have preferred the white to be a cooler white. The light is probably 5000K and I would prefer it to match the rest of my lights which are 6000K. It would also help if it was a little brighter too.

Thanks for the helps!

You could possibly get by with a 330Ohm res... Or parallel 4- 100 ohm ones. If you got an LED with a bit more of a lense to it, that would help disperse the light better too.

See this: http://www.maushammer.com/systems/tail- ... Light.html

I took a night time pic and it seems to be bright enough. It's not a huge hole so I didn't need a blinding light in it. The LED I chose says it has a 130˚ angle and I can see that it has no lens on it. It'll do for now because the light isn't really useful for anything just nice to have.

Also, the color temperature seems cooler at night and closer to my other lights. You can't really tell from the picture but the entire hole is pretty evenly lit and I can't see a hot spot. In the picture there looks like there is a hot spot right under the LED. That is a reflection from a little rubber mat that is lining the hole.

Looks nice, what vehicle?

It's my Aztek Rally! Don't say it.
http://www.xoxideforums.com/lounge/82279-my-new-first-car.html

It looks a little different now. I have the rear tail lights blacked out which makes a huge difference in the looks. I also switched every halogen light on the vehicle, inside and out, to LEDs. I got 6000K HIDs for my lows and fogs and I replaced my Highs/DRLs with 6000K LEDs. I also replaced the foglight's stock, plastic lenses with dark tinted glass lenses. It makes the fog lights kind of fade into the bumper and makes the front end looks a little less strange.

Post some new pics then... lol. At least you didnt have the rainbow apple sticker... that WOULD be gay

Lol, I'd never put one of the original apple stickers on it. They get stolen because people think they're worth a bunch of money. There've been stories about people who even put them on the inside of the glass and someone breaks the window to steal the sticker. Plus the rainbow kind of disrupts my color theme of dark and red.

Not to mention, your sexuality LOL

Haha, Yup!