AGC circuit with reference voltage

Discussion in 'The Projects Forum' started by chihiro, Dec 16, 2009.

  1. chihiro

    Thread Starter Member

    May 18, 2008
    hello everyone, got a term project of automatic gain control circuit with a given reference voltage, the circuit is not supposed to set the input voltage to the reference voltage if the output does not exceed the reference voltage, however if the output exceeds the reference voltage, i need to obtain preset reference voltage output... i had some confusions since i have to use all peak detector, difference amplifier, negative feedback and a voltage controlled amplifier. i know it sounds harsh to ask for help without doing anything but this topic is only for some helpful ideas and some ready circuits if u have any...

    some info: the biasing voltages Vcc Vee are +/- 5V, highest freq. limit is 10 kHz...

    once again: i know this post doesnt look a well-tried-before one but need a hand so much thanks
  2. chihiro

    Thread Starter Member

    May 18, 2008
    and moreover min. Vref is 100mV thanks
  3. Audioguru


    Dec 20, 2007
    You listed all the groups of parts needed to make the automatic gain control circuit.
    1) What will the peak detector do?
    2) What will the voltage controlled amplifier do?
    3) Why is there a voltage reference?
    4) What will the comparator compare?
    5) Why will there be negative feedback?

    It is very simple.