Arduino: TKs FFTDuino 2: Fast Fourier Transform Spectrum Analyzer Color Organ
Continuing the build of the FFT-based color organ.
I’m amazed at the brightness/current ratio of these LEDs. They are really bright. When I first tried them I used 5 v and 220R and they were blinding. I finally settled on 470R as a good value, and when I calculated the current based on the fwd voltage drop and the supply, I couldn’t believe the numbers so I decided to measure. The LEDs / resistors are drawing between 4.5 and 6.5 milliAmps each (except for the one mini green) and the whole display seems to stay under 40 mA when operating as FFT. This is all good.