Based on energy conservation considerations we study the nonlinear dynamic behavior of a quantum mesoscopic circuit, which is characterized through parameters of inductance and capacitance. Nonlinearity is given by the initial conditions of magnetic flux and discreteness charge which oscillate in the interval [- , + ], being the magnetic flux normalized by . This LC circuit with quantized electric charge is excited by energy battery that can produce an electrical discreteness charge on the capacitor. The dynamics of the mesoscopic circuit is highly nonlinear. Our results show for the magnetic flux a nearly square wave with an elongated period when compared with the linear case and a train of narrow pulses for the discrete charge.