A voltage regulator and a phase change memory are disclosed. In an embodiment a phase-change memory includes an array of a plurality of phase-change memory cells, an address decoder configured for receiving an address signal and selecting a sub-area in the array of the plurality of memory cells, the selected sub-area having a given number of bits of a data signal and a writing circuit including a control circuit configured for receiving the data signal and determining, for each memory cell in the selected sub-area, whether a respective bit of the data signal indicates that the memory cell is to be changed from the amorphous state to the polycrystalline state and one or more driving circuits supplied via a regulated voltage and configured for applying the set current for the first interval to the memory cells that are to be changed from the amorphous state to the polycrystalline state.