Servo Circuit Controls Sine-Wave Amplitude


Posted on Feb 7, 2014

The figure shows a schematic for an oscillator amplitude-control servo system. The circuit creates a closed-loop system that supplies a fixed and adjustable peak-to-peak amplitude ac signal centered around 0 V. A 1-kHz sine wave, labeled AC_INPUT, is ac-coupled to an AD633 multiplier chip. Then the AC_INPUT is multiplied by the SERVO signal. The m


Servo Circuit Controls Sine-Wave Amplitude
Click here to download the full size of the above Circuit.

ultiplier`s output is a scaled version of the AC_INPUT. This 1-V sine output signal is fed into a peak detector, and the peak of the signal is compared to a user-supplied reference voltage. The error integrator integrates the difference between the peak and the reference. This generates the servo signal that feeds the multiplier. The servo signal will force the peak amplitude of the AD633 output to match that of the user-supplied dc reference at the error integrator. The ac-coupling of the input signal and the frequency of the input signal are not fixed requirements. The circuit was successfully tested using a 1-kHz sine wave for the input with an amplitude of 4. 5 V, and it produced a 1-V amplitude sine-wave output using a 1-V reference for the set point.





Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    High-power battery-operated flasher
    1 khz oscillator
    wireless digital code lock with a status display
    stereo pll fm transmitter based bh1417
    mains ac xenon tube flasher circuit
    Battery charger circuit using LM317
    Small transistor amplifier Ideals
    300m FM transmitter circuit design project
    Audio Equalizer Circuits
    1W BTL Audio Amplifier
    Active Antenna
    Car Interior Lights Delay
    The current loop interface circuit diagram of AD694 being used as D / A converter



    Top