Apparatus and method for writing in phase change memory by using power calculation and data inversion

An apparatus and a method for writing data in a phase change memory by using write power calculation and data inversion function are provided to reduce power consumption for writing data on the phase change memory, by storing data with lower power consumption between write power in case of storing input data and write power in case of inverting and storing the input power. An input part(101) receives data to be written into a phase change memory. A read part(104) reads data stored on a cell position(110) of the phase change memory. An original data power calculation part(102) calculates total power consumption value for writing bits different from the previously stored data among the inputted data on the basis of power consumption value according to each bit value of the phase change memory, by comparing the inputted data with the read-out data per bit. An inversion data power calculation part(103) calculates total power consumption value for writing bits different from the previously stored data among the inverted data on the basis of the power consumption value according to each bit value of the phase change memory, by inverting the inputted data and then comparing the inverted data with the previously stored data per bit. A write part(105) stores smaller total power consumption value, by comparing the total power consumption value for the inputted data with the total power consumption value for the inverted data on the cell position of the phase change memory to be written.