Building your own ambient color lighting bars

Step 6 Wiring up the controller

Common anode goes to the 5v in and the cathodes go to the different ports. I stuck it all in a box and cut a hole in the side.

I'm running the power for my controller off the power supply for my media pc. The power supply is rated for 20A on the 5V line, but this system requires around 12A. The controller is not capable of powering off usb unless you are doing under 500ma total and this is way beyond that.

191 led's * 3 colors * 20ma = 11460ma. 11460 = 11.45A, plus a bit for the controller.

I initially powered this off my 550w power supply in my pc but with this on my 5v line drops to 4.85v from it's normal 4.98v and my usb devices start to act very sketchy. I grabbed a spare 400 watt very cheap no-name power supply which I had sitting around and it died after running this for 15 minutes. I recommend a decent brand which is separate from your computer.

If you want to use an external power supply, you can connect the green wire in the motherboard connector to a ground (any black) to power it on without a pc. You can find more details here or on google.

Comments

[barkers30]

I just come across this today and it's exactly what I've been looking. I was just wondering about the external supply though, would you be able to use something like this instead: http://cgi.ebay.com.au/12V-5V-AC-Adapter-FOR-HARD-DISK-DRIVE-Power-Supply-A057_W0QQitemZ320285880089QQihZ011QQcategoryZ111429QQcmdZViewItem

An additional info you could provide on wiring an external power supply would be much appreciated.

[the_babou]

does anyone found a better power supply than a computer one wich must waste energy for nothing used like this ?

[purpulhaze]

Possibly could find something better suited for the job but don't expect it to be as cheap as a computer power supply.

[the_babou]

in NO way, the external supply must be able to provide about 50watts that mean about 10 A (I may be wrong, tell me if i am) in this configuration, you external supply on ebay can only deliver 2A, it will burn in a few seconds ! ! ! !

[barkers30]

Ah yes, of course. Might help if pay a little closer attention. Just thought that it would be a simpler way.

[the_babou]

i am also looking for a better power supply, i will post here if i find something ;-)

[Spike002]

Yahh.... I really like the idea of this project, and actually I've been planning to build an ambient lighting thing and I have the LEDs already, but I was going off of another instructable in which they didn't use a controller. So now I'd really love to use a controller and control it with my computer or something, but I have no experience or knowledge about them. You didn't really explain exactly what the controller even does, so is there any site you can show me or could you explain it briefly for me? Otherwise this instructable is awsome, thanks!

[geofry]

Would a Arduino Diecimila USB Microcontroller Board work better for this project than a LED-Wiz or is a LED-Wiz the easiest way to go... cause im guessing ShadLight or Boblight wont work with the Arduino?

[Sh4d0w]

It'd be doable, but you are going to have to build it out more since the arduino isn't capable of driving enough pwm channels or at nearly enough current. I doubt it'd be hard to modify boblight to work with an arduino, it's already dumping out a serial port so you just need to code the arduino.

[geofry]

i think im gona go with led-wiz just to keep it simple thanks for the help... btw the rgb leds i bought are common cathode but i dont think that will make much of a difference... i believe i will just have to watch the polarity i hook it up at correct?

[purpulhaze]

I bought a bunch of the same. There is a guy who used these and built his own controller on Instructables. His site with all the specifics is down at the moment and I'm not sure when or if it will be back up.
http://www.instructables.com/id/LED-RGB-controller/

[Sh4d0w]

I wouldn't be so sure about that...

http://groovygamegear.com/PDF/LEDWIZ_INSTALL.pdf

The LED wiz is expecting the cathode to go to the ports, so if you use those LED's you won't be able to control each color properly I don't think.

[geofry]

aw that sucks... well it wont hurt to much to try it out cause my LEDs already been shipped from Hong Kong lol... if doesnt work i'll just order some more... i also sent a question about it to groovy game gear so maybe they will know

[Sh4d0w]

I'm pretty sure you could rig them up to work using a transistor, but you'd need a transistor for each individual port.............. I'm no electrical engineer so I could be wrong but at a quick glance I think you could pull it off: http://www.kpsec.freeuk.com/trancirc.htm has some good details

Once you factor in the price of buying the transistors and making the circuit more complicated you might want to just forget it and get the other LED's. *shrug*

[purpulhaze]

I'm no engineer either but I think your right. A Fet or transistor should work for that sort of set up.

[geofry]

i was thinkiing that it might work if i supply a negative voltage to the cathode but i dont know if i can do that without messing up the LED-Wiz... im just gona have to see when every thing comes in... but ur right 100 LEDs only cost 10 bucks and another 25 to ship lol

[deviouskoopa]

Hey I was looking to build this with not much prior electronics experience and based solely on this Instructable. Assuming I need to buy a computer power supply, what Wattage and brand is a good choice? Can you show me an example off Newegg or something... Thanks

[Sh4d0w]

The key is to look at the specs...

http://www.newegg.com/Product/Product.aspx?Item=N82E16817170018

This is a super cheap one and a non-name brand, but it lists under the specs +5V@36A. This is totally overkill so if the power supply is capable of putting out anywhere near that much in reality, it should work fine. All you need is around 15A. Your current PC power supply might be enough as it is.

[deviouskoopa]

Well you mentioned something about using a current PC psu but the voltage dropped and devices started bugging out... This is what I currently have running in my PC: http://www.newegg.com/Product/Product.aspx?Item=N82E16817182087

Would I be able to use this reliably without the 5V line dropping significantly and causing problems as you mentioned?

[Sh4d0w]

Should be fine. Really the best way is to just try it and see. With my power supply the 5v sits at 4.98v regularly and running the lights drops it to 4.85v.

[deviouskoopa]

Alright I'll try it out... but is there any risk involved with trying with a current psu? Like I should be able to notice stuff flakin' out and removing the lights will return everything back to normal?

[Schnullerfresser]

Nice project! I see you have wired the LEDs in parallel, so you need 12A. If you wire several LEDs in series, you would require a higher voltage, but less amps. Also your resistors would create a lot less heat. I have built a similar lamp with 279 LEDs. That would have required around 7A @ 5V. So I decided to put 3 green/blue and 6 red LEDs in series. Now I power the whole lamp with a 12V 1A supply. Because the controller runs off 5V I used an 7805 to get the 5V and 3 Mosfets (one for each colour) to drive the LEDs, because normal transistors didn't put the full 12V to the LEDs.

[dolulob]

the problem is, you cannot wire normal RGB LEDs in series, since you (usually) only have either one anode or cathode....

[Schnullerfresser]

Ouch! Of Course, you're right! I forgot that. In my lamp I used single-colour LEDs. 97x R/G/B. But I guess if you search ebay a bit, you should find some RGB LEDs with separate anode and cathode for each color. If not, try looking for those 3 Watt LEDs. They are SMD, but big enough to solder without problems and they often have separate anodes/cathodes.

[craig3]

See, here i was thinking i could make this, until i got to step 6. I have no hope of making this work now, haha

[Sh4d0w]

There's nothing complicated about step 6. The common ground between all of them goes together, the single individual wires just go into each of the ports on the controller. Anything in particular you are confused about and I'll expand on the docs a litt/e?