Input Impedance Of Inverting Op Amp. It is found that the input impedance for this op amp circuit is at least the that between non inverting and inverting inputs which is typically 1 mω to 10 tω plus the impedance of the path from the inverting input to ground i e. By doing this you will learn what opamps are all about which is what your prof intended.
By doing this you will learn what opamps are all about which is what your prof intended. If the input resistances made all equal r 1 r 2 then the circulating currents cancel out as they can not flow into the high impedance non inverting input of the op amp and the voutput voltage becomes the sum of its inputs. So the input impedance of this configuration depends upon the value of r1.
If the input resistances made all equal r 1 r 2 then the circulating currents cancel out as they can not flow into the high impedance non inverting input of the op amp and the voutput voltage becomes the sum of its inputs.
So in case of inverting op amp there are no current flows into the input terminal also the input voltage is equal to the feedback voltage across two resistors as they both share one common virtual ground source. Due to the virtual ground the input resistance of the op amp is equal to the input resistor of the op amp which is r2. Similarly apply a current to the output and calculate the change in voltage the output impedance is v i. If the input resistances made all equal r 1 r 2 then the circulating currents cancel out as they can not flow into the high impedance non inverting input of the op amp and the voutput voltage becomes the sum of its inputs.
