I bought a RGB led common anode from radioshack #276-0028 and i want to makee sure i did the calcuations right for the resistor value.
(green/blue)
Forward current: 30ma
Forward voltage: 3.5 v typ 4.0v max
(Red)
Forward current: 50 ma
Forward voltage: 2.0v typ 2.6v max
mA =(1.25/R) x 15].
For 30ma I got
1.25/650 ohms x 15=0.0288
For 50ma I got
1.25/400 ohms x 15=0.046875
Because I done the calculations for 20 ma and it gave me
1.25/1000 ohm x 15=0.01875