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Emerald

Member Since: May 30, 2014

Country: United States

  • 2.2 volts is the minimum voltage drop across the diode for it to light up. So, 24 VDC satisfies that requirement next you need to make sure the current through the diode does not exceed the max 20mA rating listed, recommends designing for 16-18mA current. Let’s say 16mA for ease of calculation. With a series circuit of power supply, LED and a resistor you get Vres = 24 - 2.2 = 21.8 V. Then simply, R = V/I = 21.8 / 16e-3 =~ 1.3kOhm.

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