Aspects of the disclosure provide a method. The method includes causing a voltage level of a signal transmitted on a transmission line to be non-linearly modified to reduce a voltage variation at a target level, and providing the modified signal to a receiving circuit that is disposed on the transmission line. In an embodiment, the method includes causing the voltage level of the signal transmitted on the transmission line to be non-linearly modified to reduce a first voltage variation at a first target level corresponding to a first digital value and to reduce a second voltage variation at a second target level corresponding to a second digital value.