This is a Simple Non Inverting Amplifier Circuit Diagram. The non
inverting amplifier has a gain of R2/R3 (1 in this case) and produces a
voltage of V,`` during a positive excursion of Vin with respect to
ground. The inverting amplifier accommodates the negative excursions of
V..; its gain is given by -R6/R7, which equals -1 to maintain symmetry
with the non invert;1g amplifier. R9 provides adjustment for the
symmetry, supply variations, and offsets. Even though the circuit
operates on a single supply, Vin can go negative to the same extent that
it goes positive. Link
Simple Non Inverting Amplifier Circuit Diagram
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