LED project for a car

[Ballard540]

I'm not sure what the deal is with my title .... never the less.

Ok the story. I am working on an LED project for a car. Having said that I have the plan figured out on how I am going to build the actual power supply for the LEDs what voltage I am going to bring it down to, which I hope is a decent design. My question is this. In my assembly I am going to have two different colors of LED (white and orange) . One is going to be on all the time (White) . While the other will come on when I apply power to it (Orange). (Power will be coming from the turn signal if you are wondering) To reduce heat on the LED and prolong life I want the first white LED to switch of when power is applied to the orange one. I need some advice on what would be the best set up of doing that. And my minor snag is that The LEDs need not switch back everytime the turn signal flashes off. If there was a good way to set up say a two second delay before it switched back to the main LED would be great. Thank you in advance!

 

[Laplace]

"One is going to be on all the time (White)."
"I want the first white LED to switch off when power is applied to the orange one."

There seems to be a difficulty with your design specifications. Also, the correct method to deal with overheating is to not overdrive the LED (if it is a low-power LED) and to use a proper heatsink (if it is a high-power LED). Trying to turn off the white LED for the brief periods that the turn signal is used will not protect the LED.

 

[Ballard540]

I'm going to use a high power LED with a 40mm x 25mm heat sink. I guess more of my reason for wanting to turn one off is yes because of heat, but more so i do not want the colors to "bleed" together. This is white and orange yes I know. But after i complete this one i will make others with different colors in them.

 

[(*steve*)]

I have the plan figured out on how I am going to build the actual power supply for the LEDs what voltage I am going to bring it down to, which I hope is a decent design.

Voltage is not the issue. Current is. You driver needs to supply a current, not a voltage.

A voltage source connected to a LED is a recipe for (eventual) failure.

 

[Ballard540]

I'm sorry I didn't take quite the time I should have to type all this. I do understand that current is everything to LEDs. Voltage is only the carrier. I am mainly concerned with how I need to make the switch to work properly