LED tailight help

[Chartoo]

Hi all.

 

Been busy working on my led taillight setup. Basically what i did was order a whole heap of those bright wide angle leds of the internet. Then i glued them into a pic of plastic and soldered them all up with a resistor on each led.

Hey presto works great for my indicators (only on and off) but im not too sure how i will do this with my stop / tail lights as there is the on / tail and brake functions.

 

How will this work with the resistors.

 

Anyone done this before?

 

Pics

Video link to the first test

[SteelToad]

You could have probably used just a single resistor instead of wiring each LED individually.

 

To replace the brake lights, lets say you're using 40 LED's you might group 8 of them together for the dimmer element, and the other 32 for the brighter element. Put a resistor in-line before each group. Make sure the 8 are not physically grouped together, you would want them spread throughout the light surface area.

 

 

                  .----O----.
 +                +----O----+        -
------////------+----O----+-------------
                  +----O----+
                  '----O----'

[Chartoo]

is there a way to make all 40 go from dim to bright?

[280Zone]

and now the video is gone.

[loy]

You could try playing around with setting up resistors in parallel, just gotta figure out the correct one with the formula.

 

I can't remember if the running lights stay on when the brake lights are applied.

[Chartoo]

i just checked the video still working and this is how i wired up the indicators

 

[Careless]

This page will clear everything up for you:

 

1 LED:

 

http://led.linear1.org/1led.wiz

LED ARRAY:

 

http://led.linear1.org/led.wiz

[Careless]

and if you happen to swear in your youtube video for no reason, you limit who can view the video in some cases

[Chartoo]

and if you happen to swear in your youtube video for no reason, you limit who can view the video in some cases

 

 

woops he he im a bit swear friendly in the shed

[SteelToad]

is there a way to make all 40 go from dim to bright?

 

You have to remember that you don't have one input with a high-low-off state, what you have is two separate inputs, one for high, one for low. You're going to make your circuit more complicated adding some switching to do that. It's by no means impossible, just more complicated.

 

Ignore what I said before about using a single resistor. I just tested here and remembered why it's a bad idea. If your LEDs arent exactly the same, the one that needs the least current will light and the others will be dim. That is, until the bright one burns out, and then the next in line will light ... until it burns out ... etc. I made the same exact mistake a few years back, you'd think it would be easy to remember.

 

If you want to get creative, you could use some tri-color (RGB) LEDs. You could light just the red lead for dim, and light all three (pseudo-white) for bright. Of course this could open some cool posibilities, maybe instead of the red leads, you tie into the blue, giving you really interesting purple (through the red lens) tail lights.

[Chartoo]

You have to remember that you don't have one input with a high-low-off state, what you have is two separate inputs, one for high, one for low. You're going to make your circuit more complicated adding some switching to do that. It's by no means impossible, just more complicated.

 

.

 

yeah this is what im talking about exactly. Any ideas on where to find plans for the circuitry?

[bjhines]

There are LED array drivers available to run large numbers of LEDs from one voltage source without resistors. These take the limiting resistor idea to the next level. They are current limiting devices using "bucking" transistorized circuits to provide enough current to drive very bright displays.

[AK-Z]

Have 3 leads coming from the array. One for ground, one with a higher resistor value and the other with the "standard" resistor value, both attached to the positive side. So the higher resistor lead will always be one but dimmer and when brakes are applied the positive will then use the the lead with the least resistance.

 

idk know if what I just wrote makes any sense. I'm on meds in another country .

[Careless]

I found this circuit driver.

it contains "light" and "stop" which i would assume are low and high output.

 

Anyone try a similar driver?

[Chartoo]

yeah im assuming there is

 

-----------------a ground wire

 

-----------------a low input-when light are on

 

----------------and a high input- when brakes are applies

 

 

so i need to make circut between these and

 

 

-----------------the postive

 

-----------------and negative on the led array.

 

This is far as my knowledge goes..............

[Daeron]

I don't understand why this is an issue.

 

 

The Brake/Tail light bulb is a dual filament bulb.

 

Install slightly less than half of your LEDs powered by the Tail light wire.

 

Install slightly more than half your LEDs powered by the Brake light wire.

 

 

KISS, right?

[AK-Z]

-------negative

 

----------resistor----- lower +

<

-----------------------High +

 

 

so low is constant. High only completes the circuit when brakes are applied

 

edit: high and low are suppose to be connected at the "<"

[Chartoo]

yeah after thinking about it half and half might be the way