Please download the dossier by clicking on the dossier button x
×

MEMORY SYSTEM AND CONTROL METHOD OF THE SAME

  • US 20170177235A1
  • Filed: 03/11/2016
  • Published: 06/22/2017
  • Est. Priority Date: 12/18/2015
  • Status: Active Grant
First Claim
Patent Images

1. A memory system comprising:

  • a nonvolatile memory including a plurality of blocks;

    a volatile memory including a write buffer configured to temporarily store data designated by a write command received from a host; and

    a controller electrically connected to the nonvolatile memory, and configured to;

    write the data stored in the write buffer to a first block, the first block being included in the plurality of blocks;

    execute a garbage collection when the number of free blocks in the nonvolatile memory is not greater than a first threshold value;

    calculate a first number based on amounts of invalid data in a plurality of second blocks, the first number being a ratio of the number of copy destination blocks needed for the garbage collection to the number of blocks to which the data designated by the write command is written, the plurality of second blocks being included in the plurality of blocks;

    determine whether the first number is greater than a second threshold value when an empty area exists in the first block and the controller receives a first command from the host, the first command being either a command for instructing preparation of power-off, or a command for requesting flushing the data stored in the write buffer to the nonvolatile memory;

    perform fill-up processing for the first block by writing, to the empty area in the first block, at least one of unwritten data in the write buffer and data written to the nonvolatile memory, when the first number is not greater than the second threshold value; and

    save the data written to the first block to a third block and write dummy data to the empty area of the first block, when the first number is greater than the second threshold value, the third block being included in the plurality of blocks.

View all claims
  • 5 Assignments
Timeline View
Assignment View
    ×
    ×