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1. Homework Statement
1) Consider an inverting operational amplifier as shown in figure. Suppose R1= 1000 ohm & Rf = 10^6 ohm. It is said that the input impedance=R1=1000 ohm and the Output impedance= 0.
2) Consider a non inverting operational amplifier as shown in figure. Suppose R1= 3500 ohm & Rf = 15000 ohm. It is said that the input impedance=infinite. Why is it so? Here Rf is the feedback resistor.But only for an ideal OpAmp, the input impedance is infinite and not for a real one, isn’t it? So, can R1 be taken as the input impedance of the OpAmp in both cases?
2. Homework Equations
3. The Attempt at a Solution
1) Consider an inverting operational amplifier as shown in figure. Suppose R1= 1000 ohm & Rf = 10^6 ohm. It is said that the input impedance=R1=1000 ohm and the Output impedance= 0.
2) Consider a non inverting operational amplifier as shown in figure. Suppose R1= 3500 ohm & Rf = 15000 ohm. It is said that the input impedance=infinite. Why is it so? Here Rf is the feedback resistor.But only for an ideal OpAmp, the input impedance is infinite and not for a real one, isn’t it? So, can R1 be taken as the input impedance of the OpAmp in both cases?
2. Homework Equations
3. The Attempt at a Solution
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