Patent ID: 7626858

Claim:
An integrated circuit having a memory comprising: a resistivity changing element having a first side and a second side; a bit line coupled to the first side of the element; an access device coupled to the second side of the element; a word line coupled to the access device for controlling the access device; and a circuit to program the element to a selected one of three or more states, the circuit adapted to precharge the bit line to a first bit line precharge voltage having a first bit line precharge voltage amplitude and then to apply a voltage pulse having a first word line voltage amplitude to the word line if the element is to be programmed to a first selected state, and to precharge the bit line to a second bit line precharge voltage having a second bit line precharge voltage amplitude and then to apply a voltage pulse having a second word line voltage amplitude to the word line if the element is to be programmed to a second selected state, wherein the first bit line precharge voltage amplitude is smaller than the second bit line precharge voltage amplitude.