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Class A amplifier

  1. Dec 5, 2011 #1
    1. The problem statement, all variables and given/known data

    Designing a Class A amplifier for project with high voltage gain and high efficency or at least as high as we can get. It has to have a 12V power supply. We have the design but the when we add the power supply that converts the 120v ac to 12v dc our output voltage goes completely wack and isn't smooth at all, yet whats coming out of the rectifier is 12V according to multisim, so whats the problem?

    2. Relevant equations

    3. The attempt at a solution

    I attached a picture of the circuit with the Vp-p output and the power supply output. This circuit doesn't produce a smooth AC output voltage when the power supply is connected.

    Attached Files:

  2. jcsd
  3. Dec 5, 2011 #2
    If the supply voltage is not smooth it suggests your smoothing capacitors are too small.
    I think I can see 1mF before the voltage regulator and 100nF after the regulator
    Do you mean 1 microFarad by 1mF or 1 milliFarad?
    100nF means 100 nanoFarads
    These seem small for smoothing capacitors.
  4. Dec 5, 2011 #3
    Can describe how you arrived at the values of the resistors and capacitors?
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