I’ve been browsing this forum and the internet now for a couple of days and what I thought would be an easy side project turned into a (for me) quite complicated matter.
I’m planning to build a mood light that consists of 12 common cathode rgb LEDs with each colour being controlled by an Arduino’s PWM pins.
In this diagram that has been posted here a while ago I found pretty much the outline for all that I want to do:
My research took me so far to understand the basic matters of a needed external 12 V Power source and the fact that I’d have to wire the LEDs parallel with respective resistors on each. What I would need help with is what transistors to choose and what resistors for them:
Should I use normal PNP transistors or a MOSFET? Are there specifically recommendable versions of each? And which resistors would I need in front of the transistor?
Important to me is, that one can control the individual colours smoothly and that there is not so much heat generation that I’d need a sink.
For more detail: The Transistor Menace – Questions regarding an Arduino rgb LED project
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