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  1. #1
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    output of the circuit

    Kindly explain how the large signal input will effect this circuit's output. what should be done if i want the output of the circuit to be oscillatory.

    Click image for larger version. 

Name:	IMG20190721133850.jpg 
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ID:	154530

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  2. #2
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    Re: output of the circuit

    No useful question without specifying the OP parameters. Too many possible answers.

    What do you exactly mean with "oscillatory" in this context?



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    Re: output of the circuit

    Quote Originally Posted by FvM View Post
    No useful question without specifying the OP parameters. Too many possible answers.

    What do you exactly mean with "oscillatory" in this context?
    can be considered as ideal opamp.
    with oscillatory i mean that can it be employed as some kind of oscillator if i use a capacitor in parallel with resistor.



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    Re: output of the circuit

    Expect the positive half wave copied to Vout. No oscillator feature.

    Connecting a real OP brings up stability issues, apparently beyond your scope.



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    Re: output of the circuit

    Quote Originally Posted by FvM View Post
    Expect the positive half wave copied to Vout. No oscillator feature.
    There is a positive feedback in the circuit.



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    Re: output of the circuit

    No positive feedback. MOSFET in CS configuration is inverting the signal, thus overall negative feedback. Practical problem is gain in feedback path, not stable with universally frequency compensated OP, additional compensation network required.



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    Re: output of the circuit

    Yes, the circuit will likely oscillate, but why do you want that?
    Zapper
    Curmudgeon Elektroniker



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    Re: output of the circuit

    Quote Originally Posted by crutschow View Post
    Yes, the circuit will likely oscillate, but why do you want that?
    can you explain how it will oscillate?
    I am just curious to know if the input to opamp is given through negative terminal or through positive terminal then how my output voltage will change.



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    Re: output of the circuit

    You show the symbol for an NClick image for larger version. 

Name:	Mosfet symbol.png 
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ID:	154533-channel Mosfet which is wrong. The Mosfet with its source terminal at the positive supply must be a P-channel.



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    Re: output of the circuit

    The symbol in post #1 is among the commonly understood PMOS symbols, see
    https://en.m.wikipedia.org/wiki/MOSFET#Circuit_symbols

    Please notice that the arrow is no substrate indicator.



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    Re: output of the circuit

    Quote Originally Posted by Akshaay View Post
    can you explain how it will oscillate?
    I am just curious to know if the input to opamp is given through negative terminal or through positive terminal then how my output voltage will change.
    My I suggest that you try simulate your circuit in one of the numerous free online simulators or whatever you prefer, then you can answer your own "what if?" questions with ease and learn more about circuit behavior at your own leisure.



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    Re: output of the circuit

    can you explain how it will oscillate?
    A circuit oscillates if the Barkhausen criterion is fulfilled. In this case if the originally negative feedback turns into positive feedback due to multiple circuit poles.

    Analysis of circuit stability needs to consider the real circuit parameters, particularly OP transfer function.



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