US Patent 7916525 Phase-change memory device

A phase-change memory device includes a data write control unit configured to generate write control signals according to a data combination of a plurality of input data and output write control codes with a code update period controlled according to an activation period of one of the write control signal, and a data write unit configured to output a program current in response to the write control signals and control a level of the program current according to a code combination of the write control codes.