Contour Enthusiasts Group Archives Forums Modifications Aesthetics Anybody that has worked with LEDs

The subject should have been a clue.

I want to do some experimentation with some LED lighting on my car now that LEDs are available so cheaply (and there some really bright ones available). My question is: how would I hook up several of then to a 12-14V circuit? Can I connect then in a series-parallel arrangement so that the combined forward voltage works out to the 12-14V? Or, should I try to use a zener diode to limit the voltage available to each "group" of LEDs that I wire together?

Any help is appreciated.

Mike

Wowww...

Ahhh... I'll take this one folks

Depending on what voltage a single LED you are using, uses, you will want to wire them in series. The voltage of the single LED will dictate how many to put in series. For example:

1 diode operates at 1.5-2.0V Car puts out 13-14.4V

You would want to have maybe 8-10 diodes wired in series.

I you need to use fewer diodes, then you will need a resistor to compensate for the lack of resistance, otherwise the LED's get really bright for only less than a second and go "pop!"

What application are you wanting to use these LED's for? Check out my site for some useful information.

OOO! I'm interested in this discussion too! I love LEDs! Make sure you keep the rest of us updated, Mike. Don't you go off on just email with Chris or somethin'!

agree with chris. find outthe resistance of each led when the circuit returns back to the power you must have 0 volts if not you will blow something. so if you have a 2v led and your running 12 volts to it you need at least a a risitor that will only let 2 volts out.

Ok, so how many ohms should my resistor be? I'd be looking to installl blue led's in my doors when I do my stereo...assuming the car puts out 12v (DC or AC?), the led's I bought at radio shack (for my psx) are 5v.....what resistor do I need? I forget a little from my ET class every day.

Thanks for the interest .

Chris, I checked out your website and I really like your idea with the LEDs in the side mirrors. I may copy your idea in the future for my car.

Some other things that I'd like to try are: 1) 'puddle lights' installed in the bottoms of the doors using white LEDs; 2) some sort of side marker (maybe custom fabbed using resin to encapsulate the LEDs); 3) augmenting the center stop light with some LEDs (LEDs light up faster; 4) using white LEDs as auxiliary lighting in parts of the interior (a string of LEDs attached to the bottom-rear of the front seats would help at night to find that small, lost toy that one of my kids dropped ).

Give me some more time and I could possibly think up some more uses .

Another question for Chris: what value of current limiting resistor did you use for your LEDs? [Or: could you give me some instruction on how to figure it out; I still remember Ohm's law .]

Thanks for your time.

Mike

TheGreatOne,

I would need to know what the ohms are on that 5V LED before I can accurately tell you what resistor value you need.

mbesket, I didn't use any resistors for the mirror markers. I used 10 per side which handle 13-ish volts just fine.

On another note for LED's, has anybody seen the new IBM laptop that has the white LED that shines on the keyboard? That was my idea. I mentioned it briefly to a co-worker when I was working for Dell. Didn't think to patent it or even write it down. They might have come up with that idea on their own though. Who knows?

Bad news Chris: I've been selling a product like that at my store for a while now. Not exactly the same, plugs into the USB and is powered off of it; with a flexable neck. Kingston makes it. Very cool. Has given me a number of ideas....

Chris: Thanks you for the information. I'll post something when I get around to doing this kind of mod.

ProudSVTDriver (and anybody else interested): you can buy those light-up things for Game Boys too ($10).

Enjoy!

Mike