Electrical – Resistors for 3W RGB LED

currentledresistors

I have 3.3V switching power supply. I want to power 3W RGB LED.

Forward voltages are: 2.2~2.8V(Red), 3.0~3.8V(Green), 3.0~3.8V(Blue)
Current: ~350mA

Should I use current limiting resistors? As I understand, for Red I need to drop 3.3V to under 2.8V and the resistor is necessary, but how to be with Green and Blue? Can I connect them directly?

Please explain.

Thanks.

Best Answer

You can't get there from here.

3.3V is not enough the reliably light the green and blue parts. and the red part with only between 0.5 and 1.1V spare may give variable performance if you use a 3.1 ohm resistor.

look instead for switched-mode LED driver that's compatible with your supply and LED.

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