What happen if I detach out R1 and C1 the circuit and connecting buffer output to -inp of 2nd stage .?hi,
R1 and C1 form a filter/smoothing circuit for the PH signal.
Also if you connected the buffer output to the -inp of the 2nd stage, Vout would be inverted.
Why do you want to change the circuit.?
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What happen if I detach out R1 and C1 the circuit and connecting buffer output to -inp of 2nd stage .?