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What Determines the Forward Voltage of an LED at low Currents?

  1. May 28, 2009 #1
    A number of years ago I required a low voltage, extremely low current, voltage regulator.

    Normal Zener diodes do not function well at low currents.

    I became aware that the forward voltage of red LED's was approximately 1 Volt at even extremely low currents (less than 1 microamp).

    My question is (and I have been unable to find an answer), what physical properties determine the forward voltage of LED's at low currents?

    Manufacturer's data sheets all indicate that it is approximately 1 Volt at very low (zero?) current.

    Attached Files:

  2. jcsd
  3. May 28, 2009 #2
    I understand it comes from the energy in electron volts of the light that the LED emits.
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