Methods of operating a memory system

• US 8,135,925 B2
• Filed: 03/28/2011
• Issued: 03/13/2012
• Est. Priority Date: 09/28/2001
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Gorobets, Sergey Anatolievich
• Primary Examiner(s): PATEL, HETUL B
• Application Number:
  US13/073,496
• Publication Number:
  US 20110173383A1
• Time in Patent Office: 351 Days
• Field of Search: 711/156, 711/159
• US Class Current: 711/154
• CPC Class Codes: G06F 3/0613 in relation to throughput
• CPC Class Codes: G06F 3/064 Management of blocks
• CPC Class Codes: G06F 3/0679 Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]

Abstract

Methods of operating a memory system are useful in facilitating access to data. Where repetitive data patterns are detected among portions of received data, and an indication is provided, a portion of the data may be stored and/or subsequently retrieved without having to store and/or retrieve, respectively, all portions of the data.

Claims

1. A method of operating a memory system, comprising:

receiving data having two or more data portions;

writing the data to a memory;

checking the data to determine whether each of the two or more data portions contain the same data pattern; and

if each of the two or more data portions of the data is determined to contain the same data pattern, storing the data pattern of one of the data portions in a sector allocation table and erasing the data from the memory.

2. The method of claim 1, wherein writing the data to a memory comprises writing the data to a non-volatile memory.

3. The method of claim 1, wherein receiving data having two or more data portions comprises receiving data having two or more data portions having a size selected from the group consisting of 1, 2 and 4 bytes.

4. The method of claim 1, wherein checking the data to determine whether each of the two or more data portions contain the same data pattern comprises XOR-ing a first data portion of the two or more data portions with each remaining data portion of the two or more data portions.

5. The method of claim 1, wherein checking the data to determine whether each of the two or more data portions contain the same data pattern comprises XOR-ing a received data portion of the two or more data portions with a previously received data portion of the two or more data portions.

6. The method of claim 1, wherein storing the data pattern of one of the data portions in a sector allocation table comprises storing the data pattern of only one of the data portions in the sector allocation table.

7. A method of operating a memory system, comprising:

receiving data having two or more data portions to be stored in a memory, wherein the data is associated with a logical sector of the memory;

writing the data to a physical sector of the memory corresponding to the logical sector of the memory;

checking the data to determine whether each of the two or more data portions contain the same data pattern; and

if each of the two or more data portions of the data is determined to contain the same data pattern, writing the data pattern of one of the data portions of the data to an entry of a sector allocation table corresponding to the logical sector of the memory, erasing the data from the physical sector of the memory, and indicating the logical sector of the memory to be erased in the entry of the sector allocation table.

8. The method of claim 7, further comprising:

if any one of the data portions of the data contains a different data pattern than any other data portion of the data, writing an address of the physical sector of the memory to the entry of the sector allocation table.

9. The method of claim 7, wherein erasing the data from the physical sector of the memory occurs after indicating the logical sector of the memory to be erased in the entry of the sector allocation table.

10. A method of operating a memory system, comprising:

receiving a plurality of sectors of data to be stored in a memory, each having two or more data portions, wherein each sector of data of the plurality of sectors of data is associated with a different logical sector of the memory;

writing the each sector of data of the plurality of sectors of data to a physical sector of the memory corresponding to its associated logical sector of the memory;

for each sector of data of the plurality of sectors of data, checking that sector of data to determine whether each of its two or more data portions contain the same data pattern; and

for each sector of data of the plurality of sectors of data, if each of the two or more data portions of that sector of data is determined to contain the same data pattern, writing the data pattern of one of the data portions of that sector of data to an entry of a sector allocation table corresponding to its associated logical sector of the memory, erasing that sector of data from its associated physical sector of the memory, and indicating its associated logical sector of the memory to be erased in the entry of the sector allocation table corresponding to its associated logical sector of the memory.

11. The method of claim 10, further comprising:

for each sector of data of the plurality of sectors of data, if any one of the data portions of that sector of data contains a different data pattern than any other data portion of that sector of data, writing an address of its associated physical sector of the memory to the entry of the sector allocation table corresponding to its associated logical sector of the memory.

12. The method of claim 11, wherein writing an address of a physical sector of the memory to an entry of the sector allocation table comprises writing a virtual address of that physical sector of the memory.

13. The method of claim 10, wherein indicating a logical sector of the memory to be erased occurs prior to erasing its associated physical sector of the memory.

14. The method of claim 10, further comprising:

wherein erasing a sector of data from its associated physical sector of the memory comprises erasing each sector of data of the plurality of sectors of data from their associated physical sectors of the memory in a single erase operation.

15. A method of operating a memory system, comprising:

receiving a plurality of sectors of data to be stored in a memory, each having two or more data portions, wherein each sector of data of the plurality of sectors of data is associated with a different logical sector of the memory;

writing the each sector of data of the plurality of sectors of data to a physical sector of the memory corresponding to its associated logical sector of the memory;

for each sector of data of the plurality of sectors of data, checking that sector of data to determine whether each of its two or more data portions contain the same data pattern, wherein a particular sector of data has a repetitive pattern if each of its two or more data portions contain the same data pattern and does not have a repetitive pattern if any one of its two or more data portions contains a different data pattern than any other one of its two or more data portions;

if each sector of data of the plurality of sectors of data has a repetitive pattern, writing the data pattern of one of the data portions of each sector of data of the plurality of sectors of data to different entries of a sector allocation table corresponding to their associated logical sectors of the memory, erasing each sector of data of the plurality of sectors of data from its associated physical sector of the memory, and indicating the logical sectors of the memory associated with each sector of data of the plurality of sectors of data to be erased in their corresponding entries of the sector allocation table; and

if any sector of data of the plurality of sectors of data does not have a repetitive pattern, writing addresses of the physical sectors of the memory corresponding to each sector of data of the plurality of sectors of data to different entries of the sector allocation table corresponding to their associated logical sectors of the memory.

16. The method of claim 15, further comprising:

if each sector of data of the plurality of sectors of data has a repetitive pattern, erasing each sector of data of the plurality of sectors of data from its associated physical sector of the memory in a single erase operation after indicating the logical sectors of the memory associated with each sector of data of the plurality of sectors of data to be erased in their corresponding entries of the sector allocation table.

17. A method of operating a memory system, comprising:

receiving a plurality of sectors of data to be stored in a memory, each having two or more data portions, wherein each sector of data of the plurality of sectors of data is associated with a different logical sector of the memory;

for each sector of data of the plurality of sectors of data, checking that sector of data to determine whether each of its two or more data portions contain the same data pattern; and

if any one of the data portions of any one sector of data of the plurality of sectors of data contains a different data pattern than any other data portion of that one sector of data, writing each sector of data of the plurality of sectors of data to the memory, otherwise storing only one data portion of each sector of data of the plurality of sectors of data.

18. The method of claim 17, wherein writing each sector of data of the plurality of sectors of data to the memory comprises writing no sector of data of the plurality of sectors of data to the memory until one of the data portions of any one sector of data of the plurality of sectors of data is determined to contain a different data pattern than any other data portion of that one sector of data.

19. The method of claim 17, wherein storing only one data portion of each sector of data of the plurality of sectors of data comprises storing only one data portion of each sector of data of the plurality of sectors of data to entries of a sector allocation table.

20. The method of claim 19, further comprising storing only one data portion of each sector of data of the plurality of sectors of data to a volatile memory before storing to the entries of the sector allocation table.