DATA STORAGE DEVICE AND OPERATING METHOD THEREOF

• US 20140006694A1
• Filed: 06/26/2013
• Published: 01/02/2014
• Est. Priority Date: 06/29/2012
• Status: Active Grant

• Current Assignee: Industry Academic Cooperation Foundation, SK Hynix Inc.
• Original Assignee: Industry Academic Cooperation Foundation, SK Hynix Inc.
• Inventors: SEO, Hyeok-Jun, KO, Seok-Min, CHUNG, Eui-Young
• Granted Patent: US 9,223,694 B2
• Time in Patent Office: Days
• US Class Current: 711/103
• CPC Class Codes: G06F 12/0246 in block erasable memory, e.g. flash memory
• CPC Class Codes: G06F 12/0253 Garbage collection, i.e. reclamation of unreferenced memory
• CPC Class Codes: G06F 2212/7203 Temporary buffering, e.g. using volatile buffer or dedicated buffer blocks
• CPC Class Codes: G06F 2212/7205 Cleaning, compaction, garbage collection, erase control
• CPC Class Codes: G06F 2212/7211 Wear leveling
• CPC Class Codes: G11C 2211/5641 Multilevel memory having cells with different number of storage levels

Abstract

A data storage device includes a first memory device configured to store data having a first property, and a second memory device including a first block configured to store data having a second property and a second block configured to store data transferred from the first memory device.

Claims

1. A data storage device comprising:

a first memory device configured to store data having a first property; and

a second memory device comprising a first block configured to store data having a second property and a second block configured to store data transferred from the first memory device.

2. The data storage device of claim 1, further comprising a request separator configured to classify data requested from outside into data having the first property or data having the second property.

3. The data storage device of claim 2, wherein the request separator comprises:

a first selection circuit configured to classify a property of the data requested from outside into the first property or the second property according to a length of the data requested from outside; and

a second selection circuit configured to reclassify data, which has a property classified into the second property by the first selection circuit, into data having the first property or data having the second property according to a request count of the data to be reclassified.

4. The data storage device of claim 3, wherein the second selection circuit comprises:

a storage unit configured to sequentially store logical page addresses (LPAs) of the data requested from outside according to a request sequence; and

a selection controller configured to reclassify data corresponding to a predetermined number of LPAs stored in the storage unit into data having the first property.

5. The data storage device of claim 1, further comprising:

a first buffer configured to temporarily store the data having the first property; and

a second buffer configured to temporarily store data that is to be transferred from the first memory device to the second memory device.

6. The data storage device of claim 1, further comprising a controller configured to select one or more data stored at a certain physical location of the first memory device, and transfer the selected data to the second memory device or store the selected data at a different physical location of the first memory device according to an update count (UC) of an address at which the data are stored.

7. The data storage device of claim 6, wherein the selected data includes data that has not been used for the longest time among data stored in the first memory device.

8. The data storage device of claim 6, wherein the controller transfers data stored at the certain physical location, which has a UC equal to or less than a threshold value, to the second memory device.

9. The data storage device of claim 6, wherein the controller stores data stored at the certain physical location, which has a UC greater than a threshold value, at the different physical location of the first memory device.

10. The data storage device of claim 1, further comprising a controller configured to perform a garbage collection operation on the second memory device.

11. The data storage device of claim 10, wherein the controller stores data, which is collected in the garbage collection operation or transferred from the first memory device to the second memory device, in the second block.

12. The data storage device of claim 1, wherein the first memory device comprises a memory device including single-level cells, and the second memory device comprises a memory device including multi-level cells.

13. The data storage device of claim 1, wherein at least one of the first and second memory devices comprises a nonvolatile memory device.

14. An operating method of a data storage device, the operating method comprising:

storing data having a first property in a first memory device;

storing data having a second property in a first block of a second memory device; and

storing data transferred from the first memory device in a second block of the second memory device.

15. The operating method of claim 14, further comprising, before storing data in the first and second memory device, classifying a property of data requested from outside into the first property or the second property.

16. The operating method of claim 15, wherein the classifying of the property of the data comprises:

a first step of classifying the property of the data requested from outside into the first property or the second property according to a length of the data requested from outside; and

a second step of reclassifying data, which has a property classified into the second property at the first step, into data having the first property or data having the second property according to a request count of the data to be reclassified.

17. The operating method of claim 16, wherein the second step comprises:

sequentially storing addresses of the data requested from outside in a storage device having a predetermined length according to a request sequence; and

reclassifying data, which corresponds to a predetermined number of addresses stored in the storage device, into data having the first property.

18. The operating method of claim 14, further comprising:

selecting one or more data in the first memory device; and

transferring the selected data to the second memory device if a UC corresponding to an address of the selected data does not exceed a threshold value.

19. The operating method of claim 18, further comprising, if the UC corresponding to the address of the data exceeds the threshold value, storing the selected data in the first memory device again.

20. The operating method of claim 19, further comprising resetting the UC corresponding to the address of the selected data when the selected data is stored again in the first memory device.

21. The operating method of claim 18, further comprising, when new data is written at an address of valid data existing in the first memory device, increasing a UC corresponding to the address.

22. The operating method of claim 18, wherein the selecting of the one or more data comprises selecting one or more data including data that has not been used for the longest time in the first memory device.

23. The operating method of claim 14, further comprising performing a garbage collection operation on the second memory device.

24. The operating method of claim 23, wherein the performing of the garbage collection operation comprises storing data collected in the garbage collection operation in the second block of the second memory device.