OPAMP İnverting Amplifiers

in the inverting amplifier circuit, the opamp connected 2 resistors 

input signal (-) is applied inseries with R1 and the output is connected to the inverting input through Rf

 (+) pin is  connected to the Ground. and  (-) pin is used  as input signal.
and so obtain  180 degrees phase  differencies.


couse of the input impedance is  very high, the current that flows on amplifier is very small, and according to I1 and If , the current can neglect.

and therefore  we can say:


 and therefore can be written;

in the opamps the gain is very high, so   


and can accept V1=0

therefore, can be prove

if Rı = R2 

in this case The  gain  is "1".

Note that the voltage at the inverting input is zero, the input signalwill see aninput impedance equal toR1, or 1K.

For more high input impedances, the values both two resistor can be increased.

Keywords : Opamp, Op-amp, Amplifiers, Inverting, Amplificator, Amplification, Info, Tutorial
Writer : delon  |
18 Apr 2006 Tue   
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