Memory device and controlling method of the same

A memory device comprising:

• a memory which has memory areas;
• and
• a controller configured to, upon receipt of write data, write data in the memory areas while managing correspondence between logical addresses of the write data and memory areas which store corresponding write data, configured to recognize a logical address group which consists of successive logical addresses, and configured to, upon receipt of a first command, shift to a real-time write enable mode, wherein
• upon receipt of a data writing instruction, the controller in the real-time write enable mode writes data in a work area temporarily prepared for a logical address group which contains the logical address of the write data in the ascending order of logical addresses of pieces of the write data, and
• assigns a logical address to the work area after completion of data writing to the last memory area in the work area.