Processing shaped data

• US 9,575,683 B2
• Filed: 07/20/2015
• Issued: 02/21/2017
• Est. Priority Date: 11/30/2012
• Status: Active Grant

• Current Assignee: SanDisk Technologies LLC (Western Digital Corporation)
• Original Assignee: SanDisk Technologies LLC (Western Digital Corporation)
• Inventors: Achtenberg, Stella, Sharon, Eran
• Primary Examiner(s): Alphonse, Fritz
• Application Number:
  US14/803,777
• Publication Number:
  US 20150324148A1
• Time in Patent Office: 582 Days
• Field of Search: 714/773, 714/770, 714/763
• US Class Current: 1/1
• CPC Class Codes: G06F 11/1012 using codes or arrangements adapted for a specific type of error G06F11/1048 takes precedence
• CPC Class Codes: G06F 3/0614 Improving the reliability of storage systems
• CPC Class Codes: G06F 3/0644 Management of space entities, e.g. partitions, extents, pools
• CPC Class Codes: G06F 3/0679 Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]
• CPC Class Codes: G11C 11/5621 using charge storage in a floating gate
• CPC Class Codes: G11C 16/3459 Circuits or methods to verify correct programming of nonvolatile memory cells
• CPC Class Codes: G11C 16/349 Arrangements for evaluating degradation, retention or wearout, e.g. by counting erase cycles

Abstract

Systems and methods of processing shaped data to include selectively performing a modification operation. The modification operation may be performed in response to determining that shaped data satisfies one or more shaping adjustment criteria. Shaping of data may be discontinued to at least a portion of a memory based on a health metric for the portion satisfying a threshold.

Claims

1. A method comprising:

in a data storage device including a non-volatile memory, performing;

determining that shaped data satisfies one or more criteria indicative of one or more particular combinations of logical pages; and

initiating a modification operation in response to determining that the shaped data satisfies the one or more criteria.

2. The method of claim 1, wherein the modification operation includes interchanging one or more logical pages of the shaped data prior to storing the shaped data to a physical page of a multi-level cell portion of the non-volatile memory.

3. The method of claim 2, wherein interchanging the one or more logical pages includes interchanging at least two of the one or more logical pages.

4. The method of claim 1, wherein the modification operation includes scrambling the shaped data.

5. The method of claim 1, wherein the modification operation includes selectively performing a logical NOT operation to bit values of one or more logical pages of the shaped data prior to storing the shaped data to a physical page of a multi-level cell portion of the non-volatile memory.

6. The method of claim 1, wherein the modification operation includes an adaptive trim operation.

7. The method of claim 1, wherein the modification operation includes a page matching operation.

8. The method of claim 1, wherein the modification operation includes a triggering operation to trigger performance of at least a portion of a write verify operation.

9. The method of claim 8, wherein a read operation of the write verify operation is performed periodically in response to determining that a bit error rate associated with the shaped data satisfies a threshold.

10. The method of claim 1, wherein the modification operation includes adjusting a threshold associated with a write verify operation.

11. A method comprising:

in a data storage device including a non-volatile memory, the data storage device configured to perform a shaping operation to shape data prior to storing the data to the non-volatile memory, performing;

determining that a health metric corresponding to at least a portion of the non-volatile memory satisfies a threshold; and

in response to determining that the health metric satisfies the threshold, discontinuing performance of the shaping operation to data to be stored in the portion of the non-volatile memory.

12. The method of claim 11, wherein the health metric corresponds to a bit error rate of the portion of the non-volatile memory.

13. The method of claim 11, wherein the health metric corresponds to a count of program/erase cycles of the portion of the non-volatile memory.

14. A flash memory device comprising:

a non-volatile memory;

a controller coupled to the non-volatile memory, the controller including a shaping unit configured to shape data; and

a shaped data tester configured to determine whether shaped data satisfies one or more criteria indicative of one or more particular combinations of logical pages.

15. The flash memory device of claim 14, further comprising a modification engine configured to perform a modification operation associated with the shaped data in response to determining that the shaped data satisfies the one or more criteria.

16. The flash memory device of claim 15, wherein the modification operation includes interchanging one or more logical pages of the shaped data prior to storing the shaped data to a physical page of a multi-level cell portion of the non-volatile memory.

17. The flash memory device of claim 16, wherein interchanging the one or more logical pages includes interchanging at least two of the one or more logical pages.

18. The flash memory device of claim 15, wherein the modification operation includes scrambling the shaped data.

19. The flash memory device of claim 15, wherein the modification operation includes selectively performing a logical NOT operation to bit values of one or more logical pages of the shaped data prior to storing the shaped data to a physical page of a multi-level cell portion of the non-volatile memory.

20. The flash memory device of claim 15, wherein the modification operation includes an adaptive trim operation.

21. The flash memory device of claim 15, wherein the modification operation includes a page matching operation.

22. The flash memory device of claim 15, wherein the modification operation includes a triggering operation to trigger performance of at least a portion of a write verify operation.

23. The flash memory device of claim 22, wherein a read operation of the write verify operation is performed periodically in response to determining that a bit error rate (BER) associated with the shaped data satisfies a threshold.

24. The flash memory device of claim 15, wherein the modification operation includes adjusting a threshold associated with a write verify operation.

25. The flash memory device of claim 15, wherein the controller includes the shaped data tester and the non-volatile memory includes the modification engine.

26. The flash memory device of claim 15, wherein the controller includes the shaped data tester and the modification engine.

27. The flash memory device of claim 15, wherein the non-volatile memory includes the shaped data tester and the modification engine or the non-volatile memory includes the shaped data tester and the controller includes the modification engine.

28. A flash memory device comprising:

a non-volatile memory; and

a controller coupled to the non-volatile memory, the controller including a shaping unit configured to shape data, the controller further including a comparator configured to compare a health metric for at least a portion of the non-volatile memory to a threshold, wherein the controller is configured to bypass the shaping unit in response to the comparator indicating that the health metric for the at least the portion of the non-volatile memory satisfies the threshold.

29. The flash memory device of claim 28, wherein the health metric for the at least the portion of the non-volatile memory corresponds to a bit error rate.

30. The flash memory device of claim 28, wherein the health metric for the portion of the non-volatile memory corresponds to a count of program/erase cycles of the at least the portion of the non-volatile memory.