No current flows into the input, Rin = ∞
The output adjusts to bring Vin- to the same voltage as Vin+. Therefore Vin- = Vin and since no current flows into Vin- the same current must flow through R1 & R2. Vout is therefore VR1 + VR2 = Vin- + IR1 = Vin- + (Vin/R2)R1
Vout = Vin (1+ R1/R2).
Vout = Vin (1+ R1/R2).
Application hint: When dealing with larger signals keep in mind that the output can't exceed the power supply voltage (i.e. if the op-amp is powered from +/- 15V and have a one volt input and a gain of 20 you won't get 20V he output. The output will most likely stop a few volts
below the supply rail (around 13V). There are special op-amps designed to handle inputs and outputs that go all the way to the power supply rail but these op-amps usually only operate at lower voltages (i.e. 0-5V).
below the supply rail (around 13V). There are special op-amps designed to handle inputs and outputs that go all the way to the power supply rail but these op-amps usually only operate at lower voltages (i.e. 0-5V).
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