I'm pretty new to this whole thing, but I think I managed to figure out just enough to be able to build what I need:
I want to control multiple RGB LEDs (not individually. there aren't enough ports supporting PWM for that...). There's a similar thread here (I've followed it - in my schematic there's only 1 LED, but following what goes on on the other thread, I know that I shouldn't group all the cathodes corresponding to the same color into 1 resistor, but give each one it's own resistor)
The problem is that I need more amperage than one can get from Arduino without going over the recommended limits, So I figured I'll just use a cellphone charger. Since I know very little about electronics, I looked it up, and found this:
So, switching out the battery with a cellphone charger (about 5v), both here and in my diagarm, I should get enough amps to connect multiple LEDs in parallel.
My Schematic:
(I'm assuming the voltage drop on the transistor is standard ~0.6V, Vf=2, 20mA for red, Vf=3.1, 15mA for green and blue in the LED)
My only concern is this: wiring two grounds together doesn't seem right. (Unless there's a diode which will prevent current flow from the ground maybe?)
So, will this work? Is my concern founded? If so, it there a simple way to fix this?
If I screwed it up too badly let me know, and I'll just buy normal grow lights and keep studying. I know this isn't the place to ask someone to do a project for you and I don't mean to do so.
Thank you!
