Hi everyone, I'm currently working on an LED array of around 80 leds to be used as a spot light (starting small, would like to use this on a 200+ led array if all works out).
I primarily want to run this off a car battery, both when the car is running or not and therein lies the problem. Once that works, I'd like to be able to power this from 240VAC as well.
Originally I was going to use resistors, but then brightness is affected when powered from the car. I then tried voltage regulating with an lm317t followed by resistors, but that was far too inefficient and made the regulator too hot even with a big heatsink (which I didn't want anyway).
So that brings me here, I stumbled accross a thread mentioning constant current buck converters and it sounded good, so thought i'd give that a shot. I've done quite alot of searching but still don't quite understand the whole concept yet and alot of what I found was either relating to high voltages/currents, or low current circuits well under the 1.6A+ that I need.
I'd also like this to be as physically small as possible and as efficient as possible, without going overcomplicated.
By the way i'll be using white 3.6v 20ma 5mm leds.
Thanks everyone.
I primarily want to run this off a car battery, both when the car is running or not and therein lies the problem. Once that works, I'd like to be able to power this from 240VAC as well.
Originally I was going to use resistors, but then brightness is affected when powered from the car. I then tried voltage regulating with an lm317t followed by resistors, but that was far too inefficient and made the regulator too hot even with a big heatsink (which I didn't want anyway).
So that brings me here, I stumbled accross a thread mentioning constant current buck converters and it sounded good, so thought i'd give that a shot. I've done quite alot of searching but still don't quite understand the whole concept yet and alot of what I found was either relating to high voltages/currents, or low current circuits well under the 1.6A+ that I need.
I'd also like this to be as physically small as possible and as efficient as possible, without going overcomplicated.
By the way i'll be using white 3.6v 20ma 5mm leds.
Thanks everyone.