Memory system

Abstract

According to the embodiments, a memory system includes a nonvolatile semiconductor memory and a writing-loop-count monitoring unit that monitors a loop count of an applied voltage to the nonvolatile semiconductor memory required for data writing of the nonvolatile semiconductor memory as a writing loop count. Moreover, the memory system includes a management table for managing the writing loop count in block unit that is a unit of data erasing and a life managing unit that determines a degraded state of the nonvolatile semiconductor memory based on the management table.

1 . (canceled) 
     
     
         2 . A system comprising:
 a memory system; and   a management unit to be installed in a host with a display device to be connected to the memory system,   the memory system comprising:
 a semiconductor nonvolatile memory which includes a plurality of blocks as a unit of data erasing; 
 a nonvolatile random access memory; and 
   a controller configured to control the semiconductor nonvolatile memory and the nonvolatile random access memory, wherein   the nonvolatile random access memory is configured to store a first information related to a degraded state of the semiconductor nonvolatile memory, and   the management unit is configured to cause the display device to display a warning based upon the first information.   
     
     
         3 . The system according to  claim 2 , wherein
 the management unit is configured to cause the display device to display a first warning based upon the first information, and when degradation has progressed, configured to cause the display device to further display a second warning that indicates a life of the memory system becomes shorter based upon the first information.   
     
     
         4 . The system according to  claim 2 , wherein
 the management unit is configured to determine which degraded stage the degraded state is among a plurality of degraded stages, and cause the display device to display a third warning that indicates the determined degraded stage.   
     
     
         5 . The system according to  claim 3 , wherein
 the semiconductor nonvolatile memory is a NAND flash memory.   
     
     
         6 . The system according to  claim 5 , wherein
 the first information is managed in block units in the semiconductor nonvolatile memory.   
     
     
         7 . The system according to  claim 6 , wherein
 the first information includes a loop count at a time of erasing in the semiconductor nonvolatile memory for each block unit.   
     
     
         8 . The system according to  claim 6 , wherein
 the first information includes a loop count at a time of writing in the semiconductor nonvolatile memory for each block unit.   
     
     
         9 . The system according to  claim 6 , wherein
 the nonvolatile random access memory is a FeRAM.   
     
     
         10 . The system according to  claim 6 , wherein
 the nonvolatile random access memory is a MRAM.   
     
     
         11 . A method of managing a memory system which is connected to a host with a display device and includes a semiconductor nonvolatile memory and a nonvolatile random access memory, the semiconductor nonvolatile memory including a plurality of blocks as a unit of data erasing, the method comprising:
 controlling the semiconductor nonvolatile memory and the nonvolatile random access memory;   storing a first information related to a degraded state of the semiconductor nonvolatile memory, in the s nonvolatile random access memory; and   displaying a warning based upon the first information.   
     
     
         12 . The method according to  claim 11 , further comprising:
 displaying a first warning based upon the first information, and when degradation has progressed, further displaying a second warning that indicates a life of the memory system becomes shorter based upon the first information.   
     
     
         13 . The method according to  claim 11 , further comprising:
 determining which degraded stage the degraded state is among a plurality of degraded stages, and   displaying a third warning that indicates the determined degraded stage.   
     
     
         14 . The method according to  claim 12 , wherein
 the semiconductor nonvolatile memory is a NAND flash memory.   
     
     
         15 . The method according to  claim 14 , further comprising:
 managing the first information in block units in the semiconductor nonvolatile memory,   
     
     
         16 . The method according to  claim 15 , wherein
 the first information includes a loop count at a time of erasing in the semiconductor nonvolatile memory for each block unit.   
     
     
         17 . The method according to  claim 15 , wherein
 the first information includes a loop count at a time of writing in the semiconductor nonvolatile memory for each block unit.   
     
     
         18 . The method according to  claim 15 , wherein
 the nonvolatile random access memory is a FeRAM.   
     
     
         19 . The method according to  claim 15 , wherein
 the nonvolatile random access memory is a MRAM.