amplifier stage

Discussion in 'Homework Help' started by propel, Apr 8, 2012.

  1. propel

    Thread Starter New Member

    Apr 8, 2012
    i am designing a gain stage for an amplifier, and have still not designed the previous stage. Im using a common-emitter. My only spec is for the amp to have an output of 8v rms, to drive the output stage. After that i am to design the first stage depending on the input requirements of this one, so no specific gain requirements apply.

    How should i go about designing it in order to get the best gain possible?
  2. panic mode

    Senior Member

    Oct 10, 2011
    when designing stages order does matter. since we are designing amplifier consider this:

    sounds like you have three stage circuit and suppose you start with first stage and finish with last one, you may find that parameters are way off. then you change one or two things and start from begin and check design when complete. this is inefficient as it can go on forever.

    proper way is to start with final stage and work your way back to input. this approach requires single pass.

    my point is that 8Vrms is not enough information and design will depend greatly on output stage (loading to second stage, swing range, supply voltage...).

    also what is best gain possible? is that the same as maximum gain?
  3. Audioguru


    Dec 20, 2007
    A single transistor with a high voltage gain has horrible distortion. Usually an amplifier uses more than one transistor so that the open-loop gain is much more than is needed and negative feedback is applied to reduce the gain and reduce the distortion.