Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Diode Barrier Potential

  1. Dec 28, 2014 #1

    For a PN junction diode, am I correct in thinking that the barrier potential (due to depletion region and hole-electron recombination etc.) is the same as the 'forward voltage' quoted on datasheets? Also, when a forward bias condition is created and the applied voltage is greater than the barrier potential, am I correct in thinking that the diode will then conduct?
  2. jcsd
  3. Dec 28, 2014 #2


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    You've pretty much got it.
  4. Dec 29, 2014 #3


    User Avatar
    Gold Member

    One thing people don't seem to get is that the conduction of a diode is a continuous exponential function.

    From the wikipedia article:
    "The diode is commonly said to have a forward "threshold" voltage, which it conducts above and is cutoff below. However, this is only an approximation as the forward characteristic is according to the Shockley equation absolutely smooth".

    The flow is exponential relative to the barrier voltage until it is dominated by ohmic effects at higher currents.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook