3
\$\begingroup\$

enter image description here

In the question above I was asked to solve the general shape of Vout, and the exact values in t=0.5ms,1ms.

My question is - can I approximate a constant virtual ground in the negative input of the opamp?

From the one hand, it's an ideal opamp with negative feedback But from the other hand, there's finite supply voltages, so it's not that simple to use the infinite gain argument (the relation Vout=A(V+ - V-) is no longer valid outside the linear regime of the opamp)

*Except the finite supply voltages, the opamp is ideal

\$\endgroup\$
1
\$\begingroup\$

If the output does not saturate the op amp will be able to keep the virtual ground.

\$\endgroup\$
1
\$\begingroup\$

When an ideal opamp model is used, there will be no DC offset at the output node - and the circuit will work without DC feedback. But only in this case!!

\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.