common source amplifier not giving proper gain on multisim

Discussion in 'Homework Help' started by Ahmed Yassien 1, May 24, 2016.

  1. Ahmed Yassien 1

    Thread Starter New Member

    May 24, 2016
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    so our professor gave us an assignment of mic to speaker amplifying cct but the output voltage is always in micro or milli volt range so i decided to start with something simple a common source amplifier but when i draw it on multisim i still get output voltage in the range of milli or micro volts

    idk how too upload the multisim design itself
     
    Last edited: May 24, 2016
  2. crutschow

    Expert

    Mar 14, 2008
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    First you have to bias the amplifier in its active region.
    Has your prof taught you about that?
     
  3. Ahmed Yassien 1

    Thread Starter New Member

    May 24, 2016
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    ughh right 4vpk should do it right ? to be in sat region?
    howwwwwwwwever now it gives const Vout (9vpp) regardless of Vinp
     
  4. Alec_t

    AAC Fanatic!

    Sep 17, 2013
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    So now you need to research how typical FET amplifier stages are configured for amplifying weak AC signals.
     
  5. Bordodynov

    Active Member

    May 20, 2015
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    See
    Com_Source2N7000.png
     
  6. crutschow

    Expert

    Mar 14, 2008
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    We normally don't do the homework problem for the op in this forum.
    We help them find a solution so they can better learn.
     
  7. Bordodynov

    Active Member

    May 20, 2015
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    I did not use multisim.
    Do you think that a beginner will be able to come up with a circuitry that specifies the mode of the transistor? He can peep it at the other, and if it you are lucky, you will find it in textbooks. I just reduced the amount of effort. Or study the difficulties is the goal?
     
  8. crutschow

    Expert

    Mar 14, 2008
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    It's trivial to transfer a circuit from Ltspice to Multisim since they are both Spice simulators.

    The goal of studies is for the OP to learn how to solve the problem on his own.
    I think it's better to direct him towards articles or tutorials that discuss his problem rather the giving him a solution.
     
    Last edited: May 24, 2016
  9. JoeJester

    AAC Fanatic!

    Apr 26, 2005
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