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Homework Help: Common emitter amplifier circuit using feedback biasing

  1. Mar 3, 2006 #1
    i don't have the basic of analog, but i tried to look for in the books. unfortunately, the books are using voltage divider biasing instead of feedback biasing.

    i have a circuit like this:

    http://www.mrnerdy.com/forum_img/BJTampfeedbackbiase.jpg

    would anyone tell me the flow of the current in the circuit, and made gain possible?
     
    Last edited by a moderator: Apr 22, 2017
  2. jcsd
  3. Mar 3, 2006 #2
    In DC, the caps are open circuits. Rc's current is given by

    [tex]I = \frac {V_2 - V_c}{R_c}[/tex]

    Current going through Rb is given by

    [tex]I_b = \frac {V_c - V_b}{R_b}[/tex]

    Since this is common emitter, then [itex]V_e = 0[/itex], then assume its forward biased then [itex]V_b = 0.7[/itex].

    Current going into the collector is

    [tex]I-I_b = \beta I_b[/tex]
     
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