Color Controllable High Power Lighting - no longer for billionaires only! Build your own fully color controllable RGB room or spot lighting for under $100. Perhaps you are asking yourself: "why would i want an any-color light?" well, for starters you can give your pets a virtual color make-over! ever wondered if Fido might look better in purple? perhaps you'd like to see your makeup the way Bono's seeing it with those blue-lens sunglasses? or maybe you're sick of your almond-white wall paint and want to give it just a tweak of eggshell today? of course, it's a gimme for the dance-party, but you can also use it to tweak the shade on your existing room lighting, or as a standalone to get any shade of white (and perfect color rendering) - invaluable for visual arts. in search of an existential crisis? i just spent a good half an hour with this light staring at my hand and trying to figure out what color it is *supposed* to be. Recently i've been using it as a portable personal light-space. you know - you walk around with an ipod to have your own sound-space, no you can walk around bathed in your own personal color too!

- Controller can power up to 360 watts of LED lighting - between 3 and 100+ power LED's
- Analog dial or slider for Red, Green and Blue - create an infinite number of light colors!
- easy to make a room light or a spot light by switching lenses / covers
- very fine analog control for precise color matching (or white matching)
- Includes current-limiting protection circuit
- Simple 7-component thru-hole circuit - No microcontrollers or programming!
- Controller cost: $25
- 50-watt, 15-LED lamp cost: $50
- Efficient: 50 watts of LED light equals 100 to 150 watts of incandescent light.
- Efficient: 80-90% controller efficiency
- Controller can be used with a variety of power sources
- Recycled materials & electronics: 20-40%

I've included a lot of detail in this instructable that applies to any power-LED project, and i've got several other power-LED instructables too, check those out for other notes & ideas. 

why not digital?? this controller was specially designed to be as simple as possible by using analog-only. it turns out that it works really well. yes, a digital PWM controller is "better", but it requires "chips" and is thus more complicated to build. i've included a circuit for a digital PWM controller here.

This article is brought to you by MonkeyLectric and the Monkey Light bike light.

Step 1: How Does Color Mixing Work?

this step explains some of the basic science behind how you can make an 'any color light' using the common technique of "color mixing".

lets start with your eye, which is an incredibly complex and sophisticated image sensor. how does your eye see an image? your eye has millions of individual sensor cells, a bit like the pixels in a digital camera sensor. your eye has 2 major types of cells: rods and cones. there are about 100 million rods, they are very sensitive to light but only see black and white images - they are your night vision. there are also about 5 million cones, which come in three types. each of the three types of cones sees different colors. you can think of the three types of cone sensors as 'red cones', 'green cones' and 'blue cones', although this is a bit of a simplification of how it really works.

so, how do we see colors? every color you can see is a result of how your brain interprets the signals it gets from the three types of cones. if you look at something and only your 'red cones' see it, then your brain sees red. if you look at something and both your 'red cones' and 'green cones' see it, then your brain interprets yellow. every color you can see is the result of how the brain interprets the different strength of signal from the three types of cones.

how does that help us? it means that using only three different colored lights (red, green and blue), we can easily fool the brain into thinking it is seeing any possible color. lets say we have a real yellow light: this light activates both the red and the green cone sensors in a specific proportion. but we can also activate the red sensor with a red light and the green sensor with a green light. if we activate the two sensors in the same proportion that the yellow light would have, then our brain can't tell the difference from a real yellow light and we see that red plus green equals yellow. we've fooled our brain!

it turns out that this is a very popular trick. every color television and computer screen ever made uses this exact principle! also most printers, cameras, and other imaging devices are based on this principle. if you have an older 'tube' screen or a plasma screen - look closely at it while it is displaying images and you can see all the small red, green and blue pixels (a magnifying glass helps).

for more information:
<p>Thanks for the great Instructable! I used it to make a grow light for starting seedlings in my not-so-bright apartment. I'm having a problem though: after running for about a minute or so, the LEDs start flickering. Also I'm not sure if it's related, but at startup, the LEDs also blink a few times at a rate about once per second before staying on continuously. My first guess is that it's insufficient heat sinking on the voltage regulator (they really do get hot!), but if this is an issue with a known solution I'd really appreciate suggestions. This is my first DIY electronic project, so I wouldn't be surprised if I'm missing something obvious.</p>
I'd recommend attaching one LED and running it at full power for a while to make sure that your attachment/heatsinking method is good before you do the rest of the LEDs. Three watts is nothing to take lightly -- they'll easily burn your fingers if they aren't heat sunk. (yep, I did that!) There are thermally conductive epoxies (basically epoxy with little bits of metal in it), so that may be an option. Check the electrical conductivity of this epoxy before using it with the 3W LEDs.
the point of this instructable is: i already did the trial-and-error work for you! i have tested the "GE Silicone 2" adhesive, and it works great with the 3-watt stars running at well over the rated power. as i mentioned above, feel free to do it the "pro" way if you want, but the purpose of the instructable is to show you some easier/cheaper ways using common materials that work just as well for this particular application.
<p>Hi I an new to this forum .I have been doing some research on Thermal conductivity of different adhesives and when mounting 3w. led's this is important. I have found when you are looking at a particular adhesive you want the highest &quot;w/mk&quot; # you can find. The higher the number the better it transfers heat from one surface to another. ie. silver has a number of 4.3 w m/k, aluminum has a number of 2.36 w/mk ,Styrofoam .03 w/mk. Arctic carry's a line of high # heat transfer compounds. ie. Arctic MX-4 Thermal compound that transfer number is 8.5 w/mk it all has to do with what is mixed into the compound to transfer the heat. Not all the compounds are adhesives though. Some you may need an alternative way to affix them to your heat sink. The most important thing is heat transfer than second should be attachment. </p>
<p>Hi all, I hate to admit it, but it's been twenty years since college algebra and I cannot, for the life of me, remember how to solve for two variables. Can someone- anyone- please walk through solving for R1 &amp; R2? It's killing me and I can't google the answer and i am running out of paper...... additionally, I am not talented at building electronics. I am attempting to build an exposure box for alternative photography techniques using H/O UV LEDs. I'm using 2.8v for my shut off voltage and 3.8 for max power. 2K or 2.5K for the potentiometer. 5 LED string x2 parallel, 28v total, 700ma LED string Current. I think that's information overkill. Help please! I want to learn how to do, so please show your work! Thanks! Johnny</p>
<p>Hi Johnny50,</p><p>if potentiometer 2K then R1=500 ohm R2=5100 ohm</p><p>if 2.5K then R1= 625 R2=6375</p><p>But your system will go hot, because the output is too much (28V). The ideal output would be 20V and 1.6 A.</p>
<p>Hello,</p><p>Which GE Silicone-2 did you use? From what I read there is a very wide range of them. (Or would any do?)</p>
Hey there, <br> <br>I tried to assemble a circuit like that with 4 SEOUL LEDs of each color (R42182, G42182, B42182), however the 10k slider I added does not seem to work like expected. <br> <br>With my 19V power source I can switch only between like 13.2V and 12.9V incoming to the LEDs. It joes does not dimm anything... <br> <br>No matter what resistors I use with R1/R2 (tried several combinations, even plain trial&amp;error), even without any resistors the circuit is just lighting. Without of course at maximum brightness. <br> <br>Anyone got an idea where I have failed here? (Also have some 12V computer power supplies laying around if that would be all it takes...)
Wow, your way is a lot more complex than mine. I basically take a full voltage and a nail and bolt and just place it on the heat sink.<br /> <br /> <a href="http://www.learningaboutelectronics.com/Articles/Why-attach-a-heat-sink-to-a-voltage-regulator" rel="nofollow">http://www.learningaboutelectronics.com/Articles/Why-attach-a-heat-sink-to-a-voltage-regulator</a><br /> <br /> But great job on putting this together. Great stuff.
hay man thanks for the hint of running the 1 watt overspec.. <br>i have also sinilar led costs .3 USD here ( yes 1/3 rd of a dollar us ) in pakistan.. they say its one watt.. i tried it running at 750mA it was muchg much brifghter but was also very hot .. so i returned back to 350mA usng pot .. so i think if i attach a large number f these to a pc heatsink and attach a 12 volts (1.5 Watt) dc brushless fan it can be very bright as well as cool and give more life ? what r ur words? have u over driven it ? can u share more info ..
when mounting the VREG with a TO220(or similar) casing, how did you manage to get the screw that holds the VREG to the heatsink, not to touch the inside of the hole in the VREG ? I always had this problem, how did you resolve it ?
Hi. Have read all your material with great interest and appreciation. Thank you. Have built your LM1084 circuit many times for LED projects. The lastest is interesting in that I designed a 1.55A array using a 0.4 sense resistor (actually 2 X 0.8 ohm sense resistor in parallel). When I measure the amperage while the circuit is ON the reading is a steady state 600ma and no where near the 1.55A the circuit should draw. Any ideas or suggestions appreciated.<br><br>Thanks again for all the helpful instructables.
I have an idea. Due to changes in the light's enviroment like temperature, time, or weather they change to preset colors. <br><br>ex.<br><br>60 degrees and under bright blue<br><br>Sunny Day Yellow<br><br>Get home from work/school Cyan
I wonder if Q1 getting really hot in a short time is normal. It is similar to the one used in this instructable.
That is normal - hence the big heat sink. The more power the regulator dissipates, the more you have to sink.
I am using an LED with these stats:<br>2.9V @ 700mA<br>3.35V @ 3A<br>I want to control it up to the max current. Seems you define R3 for a single current. Do I calculate that with the max (3A) current, giving a 0.2-Ohm resistor (closest value)? Thanks!
I'm wondering, could this potentially be used to "wash" a wall with blue or green while having foreground objects lit with "white" light. The reason I'm asking is this might be used as a "magic" portable blue or green screen for video composting. Yes? No? Maybe? Go to hell?
that should work. i dont see why not. try it, that's the only way to see.
should work, as long as your wall isnt too reflective
im pretty positive that wouldn't work at all.... good idea though, and companies like datavideo actually sell chroma key kits that work with a retro-reflective screen and a ring of green/blue leds around the camera lens<br /> <br /> <a href="http://Datavideo CKL-200 Dual-Color Chromakey Light System" rel="nofollow">Datavideo CKL-200 Dual-Color Chromakey Light System</a><br /> <h1 class="irregualrHeader">&nbsp;</h1> <br /> <br /> <br />
They sell thermal epoxy specifically for heatsinks.. a lot better than silicone. In fact, that's what the reefer led supply shops recommend if you don't drill and screw the stars down. &quot;Arctic Silver Premium Thermal Adhesive&quot;.
Hey, having a little trouble getting this to work right. Mostly it seems the resistor combinations I use won't turn off the LEDs(voltage not low enough) and won't turn them up high enough. I'm using LED's with FV of 3.2 and max of 3.75. Using a 2k pot. 19.5v supply. The LM1084IT-ADJ. What should my R1 and R2 be? Thanks!
Never-mind, I figured it out. Ended up with R1=680, R2=2.7k. I had blown the regulator chip earlier experimenting and didn't realize it! :) Dropped in a new one and presto! Thanks, this circuit deserves grand kudos!
Great instructable!! I really like it, but there is one question that comes to my mind.<br /> <br /> Lets say i have a power source V and a luxeon Led, and Resistor(R1) in between that makes the led shine in full power.<br /> and now i insert in between a pot meter in series, This would change the resistance of the circuit lowering the current, meaning making the led give off less light, never allowing to go above the R1 value which is the max.<br /> now do this three times for RGB and you got the same project with simpler circuitry don't you? why wouldn't that be good?<br /> <br /> why do you choose to use voltage regulator and transistors?<br /> &nbsp;<br /> This is my only question before i start making this instructable so could someone please explain this in detail to me? Thanks
Because the potentiometer would start smouldering and eventually fail completely. <br><br>Say the current flowing through each LED is 700mA (0.7A) which is quite common for high powered LED's. Now, if the voltage across the LED is 3.2V (full brightness), the the power being dissipated is: P=IV = 0.7*3.2 = 2.24W. If you connected a potentiometer in series with this LED then it would also have to be capable of dissipating this much power. However, most pots have an absolute maximum power rating of 0.5W which is well below what is necessary, which is why it starts smouldering. <br><br>Using the voltage regulator, the current on the input branch (the one with all of the resistors in it) is kept very low and therefore the power dissipated by each resistor is very low. But, the current in the output side can be SET (using R3) to anywhere up to 3 or 5A depending upon what voltage regulator you use.
Hello! This project is amazing - I would like to make it for some friends of mine that just got married and a house. They built their own bath tub, which is amazing in itself. Now, they would like to have some rgb LED's to light the tub romantically and who am I not to provide? But I would like to offer them some dynamics and a remote. I have found the following product:<br><br>http://www.superbrightleds.com/cgi-bin/store/index.cgi?action=DispPage&amp;Page2Disp=/specs/LDRF-RGB4.htm<br><br>but I am not quite happy since the analog driver that makes this project so beautiful is not included, which is neigh impossible with a remote I imagine. Anyway, do you have any advice for me? Thanks in advance!
I just finished making my own rgba light (yes it has amber as well !) You can see it <a href="http://www.candlepowerforums.com/vb/showthread.php?t=286602">here</a>.&nbsp; It puts out over 2400 lumens at 80watts! Thank you Dan for the best instructable ever!
is very exelent, and veri prolijed
I've been using the more &quot;simple&quot; current driver with NFET, NPN, and R1&amp;R2, and it has work great for 1watt, 3 watt and 10 watt LEDs.<br /> I'd like to construct the controllable driver with voltage regulator for use with (2) 10 watt LEDs; V= 23 volts, current = 1000ma. Cut off voltage =18 volts, max voltage= 23 volts. I'll use the 2.5K pot for R4. I need to figure values for R1&amp;R2, but I am math/calculation deficient ,Any help will be appreciated.<br />
Hi, id like to know how you cut your board. Like what tool did you use? thanks.
Looks like there's a hacksaw in that photo. That's likely what he used.<br />
&nbsp;I found this controller shield for the arduino. Does anyone&nbsp;know&nbsp;that, if properly combined with this instructables controller, it could be used to control the system. it has 10 K&nbsp;potentiometers&nbsp;and other&nbsp;useful&nbsp;inputs and&nbsp;controls&nbsp;. i figure that if the programing was done right, it would make an&nbsp;excellent&nbsp;controller module. please&nbsp;respond&nbsp;ASAP and give me advice.<br /> <br /> <a href="http://www.sparkfun.com/commerce/product_info.php?products_id=9597" rel="nofollow">www.sparkfun.com/commerce/product_info.php</a><br />
Here you can see my assembly. It cost me about $200 here in Latvia.<br /> Used single 10W led for each colour. Also I used potentiometers with switch, so I can turn off each chanel completely without the VREG burning. The hardest part in all this was getting the right R1 and R2 and insulating the VREG.<br />
forgot to say thanks to Dan :)<br /> excellent instructable<br />
For 1W LED's, would 80 degree C wire be safe enough to use?
Thank you for all the responses!
Has anybody found a new website that sells these LED's. It seems that the links he posted are now dead.
ebay is usually the cheapest.
What I was saying before I deleted my own comment was:<br/><br/>Three Things:<br/><br/>1. The link <a rel="nofollow" href="http://www.lumiledsfuture.com/">http://www.lumiledsfuture.com/</a> is outdated, you should remove it.<br/>2. The other link <a rel="nofollow" href="http://www.futurecb.com/">http://www.futurecb.com/</a> works fine, but<br/>3. In the FutureCB link, there is a parenthesis at the end of the link, making it so you can't directly access the site from the link. You should edit the link so the parenthesis isn't messing up the link.<br/>
Oh yeah you should also replace LumiLEDsFuture with FutureElectronics.com
will a different type of npn transistor work, not many a stores sell them, and cbf ordering one
I've got everything I need for this project but my potentiometers/sliders are slightly different in terms of the legs, it has five pins on each side. Attached is a diagram and some pictures (sorry bad quality). Can you please help. Tell me which leg goes to which wire. Thanks
I would say the extreme corner pins are mounting pins to create a reinforced attachment to the circuit board and the two clusters of three pins are for TWO separate potentiometer tracks. Possible from a stereo system or something.
As a matter of fact you are right, I went to my electronics teacher and he wasn't too sure either so we used his multimeter and worked out that it didn't matter which side you would solder because it gives the same output. The very outer pins are for mounting, the single inner pins are the input and the two inner pins are the variable output. Its like on a circular potentiometer it has three pins and two are the variable output. My teacher said that if you solder them together it will give you both low and high variables of resistance.
Do you own a Multimeter ? Is there any text printed on the potentiometers ? If there is text google the text plus datasheet and probably you will find more.
I do not own a multimeter, it says: B10KX2 - but that is just the model number. Any ideas?
I recommend you to buy a Multimeter if you want to do more electronic-stuff. But you can build the whole circuit and connect the wires to the potentiometer in every possible configuration. This should be no problem cause every multimeter can have the value zero.
Ok, thanks - what does a multi meter do anyways? Sorry I'm not so smart in electronics but I want to be. lol.
A multimeter measures many things it depends on the type you take but it should be able to measure: - Resistance - Voltage - Amperage
So it will help me find out which leg connects to which part of the pcb/circuit board? - Sorry not clearly phrased.

About This Instructable




Bio: Dan Goldwater is a co-founder of Instructables. Currently he operates MonkeyLectric where he develops revolutionary bike lighting products.
More by dan:Giant Xylophone made from Bed Slats Easy Mothers Day Fudge (with small child) Mosaic Tile Pixel Art Car 
Add instructable to: