Storage System and Method for Handling a Burst of Errors

• US 20180246783A1
• Filed: 05/01/2018
• Published: 08/30/2018
• Est. Priority Date: 03/04/2016
• Status: Active Grant

• Current Assignee: SanDisk Technologies LLC (Western Digital Corporation)
• Original Assignee: SanDisk Technologies LLC (Western Digital Corporation)
• Inventors: Avraham, David, Zamir, Ran, Sharon, Eran
• Granted Patent: US 10,725,860 B2
• Time in Patent Office: Days
• 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 11/1068 in sector programmable memories, e.g. flash disk G06F11/1072 takes precedence
• CPC Class Codes: G06F 16/9024 Graphs; Linked lists G06F16/9027 takes precedence
• CPC Class Codes: G11C 29/52 Protection of memory contents; Detection of errors in memory contents
• CPC Class Codes: H03M 13/1102 Codes on graphs and decoding on graphs, e.g. low-density parity check [LDPC] codes
• CPC Class Codes: H03M 13/1108 Hard decision decoding, e.g. bit flipping, modified or weighted bit flipping
• CPC Class Codes: H03M 13/1111 Soft-decision decoding, e.g. by means of message passing or belief propagation algorithms
• CPC Class Codes: H03M 13/17 Burst error correction, e.g. error trapping, Fire codes
• CPC Class Codes: H03M 13/27 using interleaving techniques
• CPC Class Codes: H03M 13/2909 Product codes
• CPC Class Codes: H03M 13/618 Shortening and extension of codes

Abstract

A storage system and method for handling a burst of errors is provided. In one embodiment, the method comprises generating a protograph using an error code generation method; generating a first partially-lifted protograph based on the generated protograph that avoids a first burst of errors; generating a fully-lifted protograph based on the generated protograph and the generated first partially-lifted protograph; and providing the fully-lifted protograph to a storage system comprising a memory.

Claims

1. A method for handling a burst of errors, the method comprising:

generating a protograph using an error code generation method;

generating a first partially-lifted protograph based on the generated protograph that avoids a first burst of errors;

generating a fully-lifted protograph based on the generated protograph and the generated first partially-lifted protograph; and

providing the fully-lifted protograph to a storage system comprising a memory.

2. The method of claim 1, wherein the burst of errors is caused by a grown bad column.

3. The method of claim 1, wherein the first partially-lifted protograph comprises K number of edges, wherein every K number of bits in a codeword contains an error.

4. The method of claim 1 further comprising generating at least one other partially-lifted protograph that avoids a respective at least one other burst of errors.

5. The method of claim 4, wherein the first partially-lifted protograph comprises K number of edges, wherein every K number of bits in a codeword contains an error, and wherein one of the at least one other partially-lifted protograph comprises N number of edges, wherein every N number of bits in the codeword contains an error.

6. The method of claim 1, wherein the memory comprises a three-dimensional memory.

7. The method of claim 1, wherein the storage system is embedded in a host.

8. The method of claim 1, wherein the storage system is removably connectable to a host.

9. A system comprising:

a memory; and

a controller configured to;

generate a protograph with minimal overlapping checks between variables; and

generate a partially-lifted protograph by lifting the generated protograph by K number of levels, wherein every K number of bits in a codeword contains an error.

10. The system of claim 9, wherein the controller is further configured to generate additional partially-lifted protographs until a fully-lifted protograph is created.

11. The system of claim 10, wherein the controller is further configured to provide the fully-lifted protograph to a storage system.

12. The system of claim 11, wherein the storage system is embedded in a host.

13. The system of claim 11, wherein the storage system comprises a three-dimensional memory.

14. The system of claim 9, wherein the error is caused by a grown bad column.

15. A system comprising:

means for generating a bipartite graph using an error code generation method;

means for generating a first partially-lifted bipartite graph based on the generated bipartite graph that avoids a first error; and

means for generating a fully-lifted bipartite graph based on the generated bipartite graph and the generated first partially-lifted bipartite graph.

16. The system of claim 15, wherein the error is caused by a grown bad column.

17. The system of claim 15, wherein the first partially-lifted bipartite graph comprises K number of edges, wherein every K number of bits in a codeword contains an error.

18. The system of claim 15 further comprising means for generating at least one other partially-lifted bipartite graph that avoids a respective at least one other error.

19. The system of claim 15 further comprising means for providing the fully-lifted bipartite graph to a storage system.

20. The system of claim 19, wherein the storage system comprises a three-dimensional memory.