aarthivg
aarthivg
Branch Unspecified
14 Apr 2012

Does Oscillator Need Feedback? If yes, Positive Or Negative?

does oscillator require feedback.If so what type of feedback? positive of negative?
B. R. Sain

B. R. Sain

Branch Unspecified
14 Apr 2012
yes, a positive feedback is required. As oscillator does not use any input ideally so it uses positive feedback. When output is applied to the input , it is called positive feedback. This is also due to the Bakhausen criterion.
anees fathima

anees fathima

Branch Unspecified
14 Apr 2012
Osillator which means producing output without input, it means we give feedback as input.The input must be positive-directly taken from output,so it is called as positive feedback.If the feedback was negative, it would serve to damp the oscillation and to "kill" the oscillator.
aarthivg

aarthivg

Branch Unspecified
15 Apr 2012
B. R. Sain
yes, a positive feedback is required. As oscillator does not use any input ideally so it uses positive feedback. When output is applied to the input , it is called positive feedback. This is also due to the Bakhausen criterion.
thanks @ B. R. Sain.
what is Bakhausen criterion
silverscorpion

silverscorpion

Branch Unspecified
15 Apr 2012
^^ Barkhausen criterion is a set of conditions under which a linear electronic circuit will oscillate.

Barkhausen Stability Criteria

Actally, the 2 condtions are, simply,

1) The loop gain should be 1 and
2) The phase shift around the lop should be zero or a multiple of 2*pi

If these conditions are satisfied, then that circuit will oscillate.
30 Sep 2018

Why - ve feed not produce oscillations

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