Feedback amplifier help

Discussion in 'Homework Help' started by dta333, Apr 11, 2011.

  1. dta333

    Thread Starter New Member

    Mar 6, 2011
    Hi all,

    Currently I am working on some homework. Where the teacher wants us to identify the feedback amplifier, based on the mixing at the input and sampling at the output. I'm stuck here, I know there are series shunt amps because he went over them in class but I don't know of others. Also how would you determine the feedback factor of the amp?
    Any help would be very grateful


    Last edited: Apr 11, 2011
  2. t_n_k

    AAC Fanatic!

    Mar 6, 2009
    The feedback mixing is either in series or parallel (shunt) with the input. Similarly the sensing is done in series with or parallel with the output. So there are four valid possibilities.

    In your first schematic the mixing is being done in series with the emitter leg - derived from voltage sensing in parallel (shunt) with the output. The feedback network "looks", in essence, like a voltage divider comprised of the 47Ω and the 2.7kΩ. This would be series-shunt feedback.

    Try to work out the nature of the feedback mixing and the sensing in your second case.