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RGB LED Home lighting project

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Today is my first visit to this Forum - and after spending the last couple of hours reading through these forums I feel that I have arrived home!

Ok... Onto my first major lighting project! I am setting up a Home cinema room and I want to do all the lighting in the room with Red Green & Blue LEDs - linked to some controller so I can change the colour/mood in the room.

I have found the exact thing I'm looking for, but alas.. these things are far too expensive for me! Check out **broken link removed**

Now... Question 1... Is it do-able to build this kind of light yourself (some electronics knowledge, but basic!)

Q2 - Any hints/tips/links/circuits/ideas/guides out there?

Best Regards,
Shure you can!

You yust need a lot leds and some transistors!

You can use a PIC to thurn on difrent led's on difrent times!

I dosent look to hard (you joust need some $$$ for all those led's)
The blue leds in particular are rather expensive. It seems it might be easier to use a couple of low wattage and/or low voltage red/green/blue bulbs which have the advantage of not being point-source type lights. Further, you could use a translucent screen to sort of blend the colors.

I triac coupled with a micro would give you the same type of control that you want now, perhaps at a lower cost and probably easier to assemble as there wont be a zillion leds.

Using 110V bulbs such as the 25W or so you can get the basic colors from the regular hardware store. If you wanted to go the low voltage route, I would use many of the little holiday bulbs. The low voltage route would probably not work with a triac, instead you could use a mosfet and PWM the lights to get the desired brightness.
I think I am coming to the same conclusion myself. Even though I love LEDs I think I might switch to using conventional bulbs (at least for my first test rig). I also have 3 of the x10 type lamp modules which I will try to wire up to the Red, Green and Blue bulb circuits to control the variable dimming... will let you know how things go!

I have accomplished what you are looking for using:

1 x BasicATOM Pro 24 Microcontroller
1 x ULM2803 Darlington driver
? x LEDS

The B-AtomPro is a programmable controller that is fairly easy to use, it is programmed in Basic and costs around $30-40US. It has a feature that sets it apart from other similar controllers in that it has 3 hardware based PWM outputs. That means it can vary the current in about 255 levels, so you can dim 3 channels independently.. RGB

The UML2803 driver takes these 3 inputs and allows you to add a whole lotta LEDs, I daisy chain the ins/outs and have 3 channels of 1amp power for the LEDS. You could probably safely drive 30-40 LEDS from one channel. And you can just add more 2803's for more leds. You can also go the way of mosfets and transistors but I used it for it's simplicity. The 2803 is probably under $1US

I buy my leds from They are extremely cheap. High Bright Leds for $0.45US-$0.65US and they sell RGB leds for about $1.10US/Each and $2.00US Shipping pretty much worldwide I do believe. The RGB leds are nice, but hooking them up is a pain as there are 4 leads where 2 would ususally go.

I like the programmable controller becuase you can hook up switches and sensors and program the effects you like and then run the thing from a push of a button. The hardware PWM is the only way to go as Software base PWM is a pain in the butt. And the code for controls is pretty simple.

eg. Dim a channel from bright to off:

FOR ledlevel = 0 TO 255

HPWM 10, ledlevel, 10


or how about brighten one channel and dim another:


FOR ledlevel = 0 TO 255

HPWM 10, ledlevel, 10
HPWM 11, 255-ledlevel, 10


I have about 75 different lighting effects programmed into mine.
You can find info on the Atom at

It's obviously not the cheapest way to go, but is by far one of the most simple. Have a look at Luxeon leds too, they kick butt in the bright department, but they are truly the brightest on the planet and I would put 3 luxeons against 75 normal leds any day..and that's my next project..


Cheers for the info - I've just been checking and I should be able to get the various components in the UK. I'll let you know how I get on...
Other Info

If you go to and go in to the documents section you fill find a HUGH amount of free training manuals, hints/tips for their STAMP controllers. The Basic Atom is pretty similar and the programming language is almost exact as the Stamp controllers. Once you've learned how to use these devices going to a Microchip PIC controller would be the next logical step as they can perform the same functions, but aren't as user friendly as the Stamp/Atom prepackaged devices. The Atom controllers have a lot more features as compared to the Stamps, but Stamps are more reliable and have a huge support base.

I use STAMPs, BasicAtoms and OOPICs for quite a bit of my projects, including anything from controlling fuel injection on my jet engines to controlling large RGB led matrixs.

I've found that they can simulate quite a few different circuits and can be used over and over again. I look at it this way, if I were to build a circuit it would probably cost just as much for the parts, time spent, and pcb design as I would spend on one of these controllers.

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