Changing the Color of an LED (Q038E)


“Can I change the color of an LED by changing the frequency of the drive current? What would be the frequencies to be used?”


In one of our articlea we explain that the light emitted by the LEDs comes from the excitation of the atoms of the semiconductor material and is independent of the voltage or current and can not be altered. For common LEDs, power must be supplied with direct current. Alternating current of any frequency should not be used and does not change the light output. In order to obtain different colors what is done is to combine the light emitted by basic color LEDs, the RGB LEDs. See 7 colors with 3 LEDs in our articles for more information.



Circuit Bench

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