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View Full Version : pwm drivers! need help. I'm confused

patrikk
06/17/2013, 06:19 AM
Hi,

I'm about to buy all the parts for my DIY led project. I was planning on buying cree leds from rapid with heatsink.


but when it comes to the power supply I have some questions.

Im planing of using arduino to be abel to control the leds ( diming etc) with PWM.

so then I guess I cant use the power supplies at rapidled in the package deals with heat sink etc?

I've also read a lot about the LDD that people have used here on this forum but those can not be used with the PS from rapid led correct?

I read that I need a power supply that has constant voltage for PWM control - comments on that?

what do I actually need for controlling the 24 LEDs diming, timer, lightning etc. with an arduino?

thanks,
daplatapus
06/17/2013, 06:33 AM
You'll need the arduino, software, some LDD drivers (or any pwm controlled drivers) and a power supply unit like the Meanwell SE-350-36. But you'll have to design your system to see what size of PSU you'll need to supply the V's and A's for your particular situation.
patrikk
06/17/2013, 07:01 AM
You'll need the arduino, software, some LDD drivers (or any pwm controlled drivers) and a power supply unit like the Meanwell SE-350-36. But you'll have to design your system to see what size of PSU you'll need to supply the V's and A's for your particular situation.


Does the LDD dim using 0-10 V but takes a pwm signal to do it or does it actually use the current to dim the LEDs?

and I got the arduino and home made software( almost finished)
pwreef
06/18/2013, 02:56 PM
LDD dims using duty cycle. At 50% duty cycle the LED is on 50% of the time.
Eud
06/18/2013, 06:49 PM
Pwreef is right.

Take a look at page 3 on the spec sheet http://www.meanwell.com/search/LDD-H/LDD-H-spec.pdf and you will see that as the pwm turns on and off you get the max current (which depends on which LDD you bought) turning on and off at the PWM frequency.
Numlock10
06/19/2013, 02:23 AM
Those drivers would suit an Arduino well as it only requires the 5v PWM signal, some of the other drivers require 10v PWM and they take a little extra work on the hardware side to make them run with the Arduino