I'm new at this forum and been messing around with arduino in the last couple of months or so, and been having lots of fun.
A friend asked me to help out with a project he's been working on, and presented me with an high powered led.
He bought that led on ebay and from the purchase page I couldn't get much information about the exact model name, but I know it's specs, which are:
P = 3W
Red = 2.0-2.4V
Blue/Green = 3.0-3.6V
And it has 4 connections, which are CRGB (Red, Blue, Green, and my guess is that C is common).
But the problem is: whenever I connect one of the colors to a digital pin, and the common to ground, nothing happens when I turn that pin on, but when I switch between the color and the common (meaning, common goes to a digital pin, and the color goes to ground) it works.
That is a problem because that means that I can't control each color individually, since they're all bunched up in ground, and not in the digital pins (PWM, by the way).
The more summarized question is: how do I connect this thing so that I can control each color separately so that I can create colors out of the RGB range?
P.S: I've attached a photo of the led for reference, there's nothing at the back (if you were wondering).
but when I switch between the color and the common (meaning, common goes to a digital pin, and the color goes to ground) it works.
So you need to connect the common to +5V and each colour, through at least a 100R resistor to a PWM pin.
It will then be inverted, that is an analogue write of 255 will turn it off and an analogue write of 0 will turn it full on. If you want to invert this then simply subtract the value you want to use from 255 before the analogue write.
NOTE:- This is for testing only, to use it correctly you will need a constant current driver supply on each colour.
You connot drive a LED like that from a Arduino directly. Not because of the connection is a problem, because it's not, but because of the amount of power. You can drive it with less power thou but what's the point of a big LED like that? Each color needs about 300mA of current. To connect it in a way you can drive it at en higher brightness you need at least a transistor and resistor for each color and a resistor for each transistor. Also, use a power supply that can supply 1A @ 5v, the Arduino can not!
And I said the configuration isn't a problem. You have to get out of your head that HIGH equals ON and LOW equals OFF. Because why? HIGH will pull the pin HIGH (to 5v) and LOW will pull the pin low (to GND). But if I connect a LED+resistor (with the anode) fixed to the 5v line and the other side (Cathode) to a pin I can control it. If i makethe pin LOW the LED turns on (connector to 5v and GND) end if I drive the pin HIGH the LED turns off because both of the pins are connector to 5V. To be off something doesn't need to be connected to GND. As long as one pin is not connected (and LOW is connected to GND, relay will really disconnect something) or both pins are connected to the same thing.
