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For an RC phase shift oscillator, the following statements are cited: a) Amplifier gain is negative b) Phase shift introduced by the feedback circuit is either 0 or 360° c) Amplifier gain is positive d) Phase shift introduced by the feedback circuit is 180° Which of the following options is correct?

For an RC phase shift oscillator, the following statements are cited: a) Amplifier gain is negative b) Phase shift introduced by the feedback circuit is either 0 or 360° c) Amplifier gain is positive d) Phase shift introduced by the feedback circuit is 180° Which of the following options is correct? Correct Answer Both a) and d) are correct

RC phase shift oscillator:

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  • RC phase shift oscillator as shown in the figure is used to invert the input for a 180° phase difference. Hence, the gain of the RC phase shift oscillator is negative. (Statement 1 is correct and 3 is incorrect)
  • The single R-C network gives the 60° phase shift. Hence the total phase shift provided by the feedback network is 1800. (Statement 2 is incorrect and 4 is correct)
  • In the RC phase shift oscillator, the inverting amplifier produces a 180° phase shift.
  • The RC Phase shift Oscillator: has a fixed frequency and is used at lower frequencies 

 

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