Electronic Help

Discussion in 'Homework Help' started by fastcharlie2, Oct 16, 2014.

  1. fastcharlie2

    Thread Starter New Member

    Oct 16, 2014
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    upload_2014-10-16_19-58-58.png

    Trying to calculate AC Vout. I did the DC analysis but dont know where to start the AC.
     
  2. b1u3sf4n09

    Member

    May 23, 2014
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    14
    Can you please show us what work you have done?
     
  3. fastcharlie2

    Thread Starter New Member

    Oct 16, 2014
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    I took the capacitor as an open and did a KVL from the 2V sourece to the 1.2kohm.
    -Vb+Vbe+Ie(100+1.2k)=0
    Ie=(2-.70/(100+1.2k)=1mA
    Ie is approximate to Ic, Ic=1mA
    Then a KVL at the output
    -10V+1k x Ic+Vout=0
    Vout=9V

    The only thing I know for AC analysis is re=25mV/Ie=25ohm
     
  4. t_n_k

    AAC Fanatic!

    Mar 6, 2009
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    One would need to know the source frequency since there are frequency dependent components in series with the source.
     
  5. fastcharlie2

    Thread Starter New Member

    Oct 16, 2014
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    The frequency is from 1kHz to 100kHz. But I dont understand how to do the AC analysis of this circuit.
     
  6. t_n_k

    AAC Fanatic!

    Mar 6, 2009
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    Are you able to draw the small signal AC equivalent circuit? This is essentially a grounded base configuration. How would you know that it is grounded base?
     
  7. fastcharlie2

    Thread Starter New Member

    Oct 16, 2014
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    0
    upload_2014-10-17_11-6-52.png

    I got it like this for the AC small signal but what do I got to do next?
     
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