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Diode polarity means?

  1. Dec 14, 2014 #1
    What is meant by diode polarity. If we do connect anode to positive and cathode to negative then its means it works on Forward Bias mode. I think positive means higher potential than negative, in other words, if positive terminal which is Anode is to be at 5 volts and negative terminal which is Cathode will have to at 2 volts then Diode will work in Forward bias region.? Please explain if I'm right understanding of this.
  2. jcsd
  3. Dec 15, 2014 #2


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  4. Dec 15, 2014 #3
  5. Dec 15, 2014 #4


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    so is there something specific on any of those 2 links that you don't understand in how it may answer your original question ?
  6. Dec 17, 2014 #5


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    Hi Usame. You have it right. All the diode itself sees at its terminals is the potential difference there.

    But with 3V across the diode and no current limiting, the diode current will be very high (remember, it's an exponential relationship). If it is a low power diode it will instantly burn out. A big power diode constructed like a bolt so it can be mounted on a heatsick, will be capable of withstanding 3V in forward conduction. It has some ohmic resistance and this will help limit the current.
    Good luck with your studies! http://thumbnails111.imagebam.com/37333/4d0696373324852.jpg [Broken]
    Last edited by a moderator: May 7, 2017
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