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PNP versus NPN bipolar transistors

  1. Aug 1, 2014 #1

    Could anybody explain me why the base current of a pnp is higher than a npn for the same collector current?

  2. jcsd
  3. Aug 5, 2014 #2
    It depends a great deal on the particular transistors. Some are designed for high current, some for low, and the current gain varies with many different influences: current, voltage, temperature for starters.
    Some manufacturers do make complementary pairs of transistors in NPN and PNP which are designed to match each other reasonably well, for push-pull applications.
  4. Sep 7, 2014 #3
    The simple reason traces to hole mobility - which translates to a lower beta - which translates to a higher Ib for the same Ic value compared to an NPN.
  5. Sep 7, 2014 #4


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    Science Advisor

    A transistor which has less current gain than another will require more base current for the same collector current.

    PNP and NPN transistors come in a variety of current gain versions, so you couldn't claim PNP types have lower gain without producing some evidence that this is true.
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