Amplifier design level shifting stage w/ current source equations

Discussion in 'Homework Help' started by wazzizit, May 30, 2015.

  1. wazzizit

    Thread Starter New Member

    Jan 14, 2015
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    Could anyone help by giving the equations used to calculate the resistor values in the circuit attached please?

    Many Thanks :)
     
  2. Jony130

    AAC Fanatic!

    Feb 17, 2009
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    All transistor in your diagram are connected backward or simply you are using wrong transistor type.
     
  3. wazzizit

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    Jan 14, 2015
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    The top and bottom power supplies are the wrong way round. Assuming they're flipped, how do I derive the res values please?
     
  4. Jony130

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    Feb 17, 2009
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    Well all you need is Ohm's law and two Kirchhoff's laws.
    Ic2 = Ic1 = Ic3 = (Vd - Vbe1)/R1
    And
    Vo = Vi + Vbe3 +Ic3*R3
     
  5. wazzizit

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    Jan 14, 2015
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    Any chance you could sub in some values please? I'm struggling to know what the Vbe, Ic2, Ic1 and Ic3 values are
     
  6. Jony130

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    You do not know what Vbe is ??
     
  7. wazzizit

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    Jan 14, 2015
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    I know it's the voltage from base to emitter...
     
  8. Jony130

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    And typical Vbe values is ??
     
  9. wazzizit

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    Jan 14, 2015
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    .7V?
     
  10. Jony130

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    Yes.
     
  11. wazzizit

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    Jan 14, 2015
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    Always? how about the currents?
     
  12. crutschow

    Expert

    Mar 14, 2008
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    You need to take a stab at it before we can help.

    The is Homework Help forum, not a Do Your Homework one. :rolleyes:
     
  13. wazzizit

    Thread Starter New Member

    Jan 14, 2015
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    Please see my other thread where I have posted half of my efforts on this task so far.
     
  14. Jony130

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