Mood lamp without mcu

Thread Starter


Joined Sep 18, 2009
Hi there,

I want to make a "mood lamp". Is there a way how to do it without need of a MCU?

There should be 16 red LEDs, 16 green LEDs, 16 blue LEDs.

And if it is possible there should be a potenciometer which will control the speed of transition. Maybe via PWM.

Anyone can help???


Joined May 9, 2009
Get some automatic rainbow color LEDs which cycle color over a few seconds. Wire them in series. The LEDs need to be powered from about 15V for 5 LEDs.

The varying voltage across each LED due to sudden transitions will create a quite nice mood light, causing the LEDs to reset mid-cycle and run at different speeds.

However the speed cannot be easily changed.


Joined Dec 20, 2007
Years ago I made many Mood Lamps with opamp triangle-wave generators. The 3 oscillators oscillate slowly at different frequencies so the RGB colours add "randomly" and produce millions of colours at all brightnesses. The LEDs have a wide-angle beam so their colours overlap on the ceiling.