Subtraction circuit

Shown is a subtraction circuit. The voltage is added to
the inverting input terminal of the operational amplifier through Ri, the voltage is divided by R2 and R3 and then added to the non-inverting input terminal,
and the pump is fed back to the inverting input terminal through Rf. In order to
balance the two input terminals of the operational amplifier, }Rl/,RrRzllR3.
    The output voltage of the subtraction circuit is equal to the difference between the two input voltages, thus realizing the subtraction of
the two input signals . The subtractor fork is called a
differential input arithmetic circuit and has a suppression effect on common-mode signals. Therefore, the subtractor can not only subtract signals, but can also be used to amplify signals
containing common-mode interference .