PHASE VARIATION MEMORY DEVICE OPERATING AS NONVOLATILE MEMORY AND VOLATILE MEMORY SELECTIVELY AND OPERATING METHOD OF THE SAME

摘要

PURPOSE: A phase variation memory device is provided, which operates as a nonvolatile memory and a volatile memory selectively and is driven by a small current. CONSTITUTION: A memory array block(410) comprises a plurality of phase variation memory cells connected to a word line and bit line pair. A write control unit(420) writes data into the phase variation memory cell in the memory array block in response to a data signal, an inverted data signal, a reset current, and a set current, and it writes data into the phase variation memory cell again in response to a rewrite control signal. A transmitter unit(430) amplifies data being output from the memory array block, and transmits the amplified data to a local input/output line(LIO,/LIO) in response to a column selection signal. A global input/output line(GIO,/GIO) receives data from the local input/output line and then outputs it to the external, and transmits the data to the write control unit in response to the rewrite control signal. And a current source unit(440) varies the intensity of the reset current and the set current according to an operation mode.