1. A method of changing data states in a non-volatile memory integrated circuit, comprising: applying at least one voltage pulse to a non-volatile memory cell including a steering element in series with a state change element; changing an amplitude of said at least one voltage pulse during said applying to increase an amount of bias applied to said non-volatile memory cell; and changing a resistance of said non-volatile memory cell from a first resistance state to a second resistance state by applying said at least one voltage pulse.