Astable Multivibrator Using 741 Op-Amp

Posted on Feb 6, 2014

The positive feedback comparator circuit increases the gain ofthe op-amp, which helps to switch very fast between the two states of a multivibrator. The positive feedback also provides hysteresis to the circuit. A capacitor `C` is connected to the inverting terminal of the Op-Amp with its other end grounded. The capacitor along with the resistor `R`

Astable Multivibrator Using 741 Op-Amp
Click here to download the full size of the above Circuit.

acts as a RC integrator. The vol;tage across the capacitor is given by Vc. Thebelow figure demonstrates the working of an Astable Multivibrator using IC 741 Operationalamplifier, consisting of a comparator circuit having a positive feedback with a feedback factor. Now, the op-amp has a voltage of `Vc` at the inverting terminal and [R2/(R1+R2)]Vo atthe non-inverting terminal, giving rise to a voltage equal to+Vsat or -Vsat at the output. On the other hand at the inverting terminal, the capacitor tries to charge to +Vsat, which is available to the capaciror through `R`. but on the way to +Vsat, when the capacitor reaches at a potential equal to the potential at the non-inverting terminal of the op-amp. Since the op-amp behaves as a comparator circuit, the output changes from +Vsat to -Vsat, because the inverting potential is greater than non-inverting potential.

Leave Comment

characters left:

Related Circuits

  • New Circuits



    Popular Circuits

    AM/cw 10-meter band transmitter
    autopilot with rev 2.2 board
    10 To 1Hz Timebase Circuit
    Rf Signal Generator Circuit
    Laser Beam Light Activated Remote Control Circuit
    ethernet Poor eye diagram where to start looking
    converting circuits to c
    120 vac lamp dimmer
    A Mixed-Signal LED Clock
    Voice Shield for Arduino
    Tabletop Tree Lights
    555 IC using a delay circuit ter