How to calculate the amplification factor of operational amplifier

What is the inherent magnification (open-loop magnification) of the integrated operational amplifier? Generally, it is more than 10000 times (equivalent to 80dB). Although the open-loop magnification of integrated operational amplifier is high, it is nonlinear and has poor temperature stability, so it is not interchangeable. Therefore, integrated operational amplifiers are generally used in closed loop (feedback).

When the integrated operational amplifier is used in closed loop, the magnification is generally limited to 100, which is relatively stable and has good linearity. And the chips are interchangeable. Magnification G=()R2/R0,? G has nothing to do with R 1 Don't use R 1, it has no positive effect.

Operational amplifier is an amplifier circuit that can perform mathematical operations. Operational amplifiers can not only amplify by increasing or decreasing analog input signals, but also perform operations such as addition, subtraction and calculus.

Extended data

The circuit symbol of the operational amplifier has two input pins, namely the noninverting input terminal Vin(+) and the inverting input terminal VIN (-) and an output pin Vout. In fact, the operational amplifier also has power supply pins (+power supply,-power supply) and offset input pins, which are not shown in the circuit symbols.

The main function of operational amplifier is to amplify the difference between two analog signals with high gain. We call an operational amplifier that amplifies the difference between two input voltages a differential amplifier. When the voltage of Vin(+) is high, the output is amplified in the forward direction. When the voltage of vin (-) is high, the output is amplified negatively. In addition, the operational amplifier has the characteristics of extremely high input impedance and extremely low output impedance.

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