Resistance variable memory device performing program and verification operation

[0023] Embodiments of the invention will now be described in some additional detail with reference to the drawings. However, the invention may be embodied in different forms and should not be construed as limited to only the illustrated embodiments. Rather, these embodiments are presented as teaching examples. Throughout the drawings and specification, the same reference numerals and symbols are used to refer to the same or similar elements.

[0024] Throughout the description below, phase change memory is used as an example of a broader class of variable resistance memory devices. Embodiments of the present invention cover all classes of variable resistance memory devices, not limited to phase change memory.

[0025] figure 1 is a block diagram of a variable resistance memory device according to an embodiment of the present invention. refer to figure 1 , variable resistance memory device 100 includes memory cell array 110, write and verify driver 120, write buffer 130, d...