A circuit provides a first current corresponding to the differential input Inn and Inp, and a second current corresponding to the common mode input Vcm. The circuit then mirrors the differential current and the common mode current to a third current and a fourth current. Based on the difference between the mirrored differential current and the mirrored common mode current, the circuit pulls up or pulls down these currents to balance the corresponding difference between the differential input and the common mode input. In effect, the circuit adjusts the input common mode voltage to a desired level, without providing an opportunity for it to rise to an unwanted level.