Hi everyone
I am a total noob so please bear with me. I am in the middle of makeing a light bar for my jeep and I am using some high power leds (SST-50).These will be wired in series. The specs of the leds are MaxVf 3.6v and 5A max. I am in need of a power supply that can use my car battery as a source voltage(12-14vdc) and output needs to be adjuatable from 0-15v(what ever my Vf of led string is, 3.6v x 4 leds=14.4v) and 4 to 5A fixed. Is there any way this can be done? I am no stranger to using solder, heatsinks and all that good stuff I just need help in the design. Any help would be appreciated.

 

If you're wanting to vary the brightness of the LEDs I'd keep the voltage at full and feed them with a variable duty cycle pulse. LEDs don't exactly dim like light bulbs do. From 0V you have a long period of nothing followed by a minimal amount of adjustment as the amount of current is varied through them while they're conducting.

 

No I do not want to vary the brightness of them so I guess I need a fixed input voltage 12v (engine not running)(close to 14v egnine running). And a fixed 5A output and Vout needs to be my Vf of leds.

 

You'd get the most efficiency with the "4 in series" method so just need a buck/boost regulated supply capable of providing the 5A would be required.

http://www.luminus.com/stuff/conten...3_sst_50_w_product_datasheet_illumination.pdf

 

Oops - this is a topic that is no longer open for discussion on the forums.

Please see the "Automotive Guidelines" in the General Electronic Discussions forum.

Vehicle exterior lighting is one of the prohibited topics.

 

Hello,

SgtWookie is right.
Vehicle exterior lighting is one of the prohibited topics.
It is a safety matter.

Bertus