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The circuit given in the problem

What is a modified forward path?

In the practise exam paper I'm doing I'm given this circuit and asked to draw an equivalent circuit of the 'modified forward path amplifier'. I'm told that it should include all resistive loadings of the source, load and feedback network but should ignore actual feedback gain.

I've looked through my course notes and google, but haven't been able to find out what a modified forward path is.

Could someone please explain?

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I think, it is your task to find a small-signal equivalent circuit diagram including opamp input and output resistances, which - normally - are neglected. However, they cause loading effects which in this case must not be ignored. See, for example, here (pages 70, 71):

https://books.google.de/books?id=V7sqBgAAQBAJ&pg=PA70&lpg=PA70&dq=modified+forward+path+amplifier&source=bl&ots=XFoZbm3bkA&sig=45aXgCAjYaIM9HFYGXOmtBre7Vs&hl=de&sa=X&ved=0CCgQ6AEwAWoVChMIsKXXsNnfyAIVKJNyCh3qnAWS

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Since it's a feedback system, I think your professor refers to the left-to-right path, instead of the one that you could analyse right-to-left. What you had to do is to consider your input signal, and draw an equivalent circuit of that left-to-right path, until you get your equation for your output signal.

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Conventionally, an inverting amplifier configuration has \$V^+\$ grounded and the input signal applied to \$R_1\$. The circuit, above, is a variation of this.

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