PHASE CHANGE MEMORY DEVICE

摘要

A phase change memory device is provided to perform efficiently a write operation by applying a set voltage and a reset voltage corresponding to characteristics of a phase change cell of each unit in a write operation mode. A cell array unit includes phase change cells(C) which are arranged in crossing regions between word lines(WL0-WL3) and bit lines(BL0-BL2). A voltage selection control unit selects one of a plurality of multi-voltages according to voltage control signals and outputs the selected voltage as a driving voltage. A write driving unit(W/D) controls finely a level of the driving voltage according to voltage fine control signals and supplies the controlled voltage to the cell array unit.