# output of the circuit

1. ## 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.

2. ## 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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3. ## Re: output of the circuit

Originally Posted by FvM
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.

4. ## 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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5. ## Re: output of the circuit

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

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6. ## 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.

7. ## Re: output of the circuit

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

8. ## Re: output of the circuit

Originally Posted by crutschow
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.

9. ## Re: output of the circuit

You show the symbol for an N-channel Mosfet which is wrong. The Mosfet with its source terminal at the positive supply must be a P-channel.

10. ## 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.

11. ## Re: output of the circuit

Originally Posted by Akshaay
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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12. ## 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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