Pages: [1]   Go Down
Author Topic: Basic RGB Led Strip Controlling  (Read 939 times)
0 Members and 1 Guest are viewing this topic.
Offline Offline
Newbie
*
Karma: 0
Posts: 1
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

Hi,

I am looking for help on how to control the color a 2 meter RGB strip through a computer. They are 12V.

I have found different ways on going about doing this, but most are a couple years old, and each method seems to use different parts. I just want to know what is the best current method to controlling the led strips, what I need to buy, and how I should connect all those things.

Yes I am new to this, so any help is greatly appreciated.  smiley-mr-green

Manny
Logged

Offline Offline
Newbie
*
Karma: 0
Posts: 38
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

You and me both. Haven't ever used an Arduino but am anxious to learn it to control a 10m length
of HL1606 LED's. Hope to be able to sync effects with a soundtrack somehow.

Carl
Logged

Offline Offline
Jr. Member
**
Karma: 0
Posts: 95
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

The best method is using 3 PWM pins, each pin will then control a transistor and each transistor will control one of the colours.

Giving specific details of which transistors or the size of the external power supply is impossible without more details about your LED strips.

Are the common Anode or common Cathode? How many LEDs are there per meter? etc etc.

(picture stolen from google images, you will probably want 12V dc supply capable of 1-2 amps rather than then 4.1V shown in the pic).
http://i54.tinypic.com/2qjlobd.jpg
(the LED would be replaced with the whole strip and you would need one per colour).
Logged

Boston Suburbs
Offline Offline
God Member
*****
Karma: 14
Posts: 955
I am above your silly so-called "Laws", Mister Ohm.
View Profile
WWW
 Bigger Bigger  Smaller Smaller  Reset Reset



   

This is a RGB+White LED floodlight I'm building.. 3 watts each of color, one watt LED's.  When complete, it will have two heads, for a total of 24 watts.

You are going to want to do PWM fading, which is what allows for color mixing.  In this video I just have tossed a plastic cup over it as a diffuser, and I am running at reduced current so that I don't fry a retina.  Three watts of LED light from a few inches away is BLINDING and leaves afterimages for quite a while.  

A decent switching transistor is what is needed, I've always been a big fan of TIP120, as it can handle a lot of current and has a very high gain (meaning you can control a lot of power with a little bit going in).  If I remember correctly, TIP120 can handle 5 amps, which is more than you need.

For my build, I am using smaller transistors (rated for 600mA) as I am only driving 350mA, and LM317 constant-current drivers.  Power comes from the switching 12v power supply, it can pitch out 12amps if required, a bit of overkill but it was in the bins.  The board I made does each channel independently, so it has eight individual power supplies and switching transistors.  On the board, the power regulators are the devices with the heatsink tabs and are in the rear of the board, the switching transistors are near the front and are actually a bit smaller and have no heatsinking tab.

On the Arduino side, it's just four lines (red,green,blue,white) and power/ground.  I've just got it sending random levels in this demo, I'll have a few fades and washes and the like written up in a few days.
« Last Edit: October 13, 2011, 11:43:48 pm by focalist » Logged

When the testing is complete there will be... cake.

Pages: [1]   Go Up
Jump to: