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Homework Help: Transistor Circuit

  1. May 14, 2014 #1
    1. The problem statement, all variables and given/known data
    So I am supposed to find Vo in this circuit. Given, Vb-Ve=0.7, ic=100ib, ie=ic+ib

    3. The attempt at a solution
    In order to solve for Vout i did KVL for the two loops:

    Loop 1 (left side, clockwise):


    Ve=ie(416)=2.18V (this one i am not sure)

    Loop 2 (Right side, anti-clockwise)

    Subbing in everything i get

    But the answer is supposed to be 5 Volts, i am not sure where i made a mistake.

  2. jcsd
  3. May 14, 2014 #2


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    Science Advisor

    The 2V and the 0.7V in the left hand loop are in opposite directions, so they should subtract, not add, so you should get 1.3-52016*Ib=0.
    Last edited: May 14, 2014
  4. May 14, 2014 #3
    I still don't get the right answer, this time around i get 7.87
  5. May 15, 2014 #4


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    Science Advisor

    You've made another mistake in the right hand loop, but you don't really need that. With what I gave you, you should get Ib = 25μA. Ic = 100* Ib = 2.5 mA. Vout = 10.0 - 2.5mA * 2.0 kΩ = 5.0V
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