100 x LED Yellow 3mm Round

LED Yellow 3mm tinted, clear LED in T-1 package.

The max. continuous current is 20mA, resulting in 2.0-2.1V forward voltage.

LED Yellow 3mm are operated at constant current, not voltage! It is necessary, to limit the LEDs forward current with a resistor.

The value of the resistor is easy to calculate following Ohm's law: R = U / I. For example, on a 12V power supply, U = 12-2 = 10V, I = 0.02A. The resistor in this circuit should not be less than 10V / 0.02A = 500 Ohm (for max. brightness).

LEDs, operating on their current limit, are barely producing more visible brightness than when operated with a lower current, but they will have a much shorter life span. Therefore, we always set the LED current to about 1-5mA in our developments.