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General Category => General Discussion => Topic started by: mattias89 on February 04, 2011, 13:56:36 PM

Title: Car Front LED Delay
Post by: mattias89 on February 04, 2011, 13:56:36 PM
Hi!
I have 2 pcs of http://www.stylingbutiken.se/flextube-vit-24cm-/2309-0

I now want the following action from the led delay.

When I turn off the car, I want the leds to be on for a couple of more secounds say for example 10 secounds. I Dont need any resitors because the leds are 12 V already and they can function with my battery.

What do I have to buy and how will I construct my LED delay?

Thank you very much.

I have bought transistors 2n222 and a lot of capicators
Title: Re: Car Front LED Delay
Post by: kam on February 05, 2011, 14:01:51 PM
Hi mattias89. You need an LED off delay circuit. Google for one, or use mine:

LED Off Delay with dimming effect (http://pcbheaven.com/circuitpages/LED_Off_Delay)

Because your LEDs are ready for 12V, you will connect them in parallel (as many as you like) and then directly to the emitter of the 2n2222 (i use the same transistor). Hope this circuit is ok for you.
Title: Re: Car Front LED Delay
Post by: kam on February 05, 2011, 14:03:40 PM
Oh, and something else: How much current each one draws? Is important for the 2n2222 transistor. Do not exceed the total power dissipation and mac current