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Topic: Project help - Cree LED, Drivers, and Arduino (Read 619 times) previous topic - next topic

Idiosensory

I am pretty new to all of this so please forgive my ignorance. I have been working with an Arduino and a bread board and am trying to apply what I learned to a real world project. I have 6 Cree LED lights that I am hooking up in a light panel, each light will be 2 ft apart. I want to control the lights with the Arduino. From bread board to real world, how do I get there? Right now prototyping is powered through the Arduino, but for the Cree I will need to add a power supply, I am also using drivers in place of resistors. I also need to be able to run clean wiring at some distance since the lights will be 2 feet apart. I can't find anything that explains how you might put this together, like do I wire everything back to a perfboard and then wire that to the Arduino. How do I introduce a power supply and driver? What is the cleanest way to run wires at length?

Any help or direction to a "how to" is much appreciated.

Thanks,

PeterH

I don't know anything about Cree lights, but you will need to know how they can be controlled. If you don't already know, you will need to find out. Is it just a matter of switching the power supply on and off? If so, you need to know what sort of power supply they use and select some hardware capable of being controlled by an Arduino which can switch that voltage and current. At the same time you will need to decide whether you are going to use an Arduino board (and which one) or design your own hardware, and this will constrain which switching shields/boards are available to you. This decision will dictate the types of connectors available to you and hence what sort of wiring connections you will need.
I only provide help via the forum - please do not contact me for private consultancy.

JoshD

Another thing to take into consideration is heat.  Depending on which Cree LEDs you're using, you may need to mount them on a pretty substantial heat sink rather than perfboard.  Failure to do so may result in one bright flash of the LED followed by immediate and permanent failure.  As for the rest, like PeterH said, the answers to your questions depend on what specific hardware you're using.

Idiosensory

Thanks so much for your help, here is what I am planning to use:

6x Cree Cool-White XP-E 1-Up Indus Star - 3.0Vf - Typ. Forward Voltage @ 350mA
Luxdrive FlexBlock - Max Output Current: 350mA, Max Input Voltage: 32VDC, Min Input Voltage: 10VDC, 0-10V Dimming Compatible
12VDC, 2.0A, 25Watt Power Supply

I will be mounting to a heatsink. Would a switch board allow me to bring this together with clean wiring? Do you know a good place to pick something like that up? Does this configuration seem compatible?

Again, thank you for your help.

PeterH

I don't know what that list of parts means. Is there a mechanism to turn them on and off in there somewhere?
I only provide help via the forum - please do not contact me for private consultancy.

JoshD

#5
Dec 29, 2012, 03:10 am Last Edit: Dec 29, 2012, 03:29 am by JoshD Reason: 1
It looks like it can be dimmed with a 10V PWM signal.  Since the driver can also run on the same voltage, using a 10V power supply might simplify things.  Then you'd just need a transistor to convert the arduino's 5V PWM signal into the 10V that the driver needs for dimming.  There's lots of examples of how to do that floating around.

EDIT: Oops, I just noticed...  Looks like it needs a 200hz pwm signal.  You'll need to change the PWM frequency on the arduino or generate the 200hz signal using software.  A 20k digital pot is also an option.

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