HYBRID FLASH MEMORY DEVICE AND METHOD OF CONTROLLING THE SAME

• US 20090248965A1
• Filed: 03/10/2009
• Published: 10/01/2009
• Est. Priority Date: 03/25/2008
• Status: Abandoned Application

• Current Assignee: Asmedia Technology Incorporated (ASUSTek Computer, Inc.)
• Original Assignee: Asmedia Technology Incorporated (ASUSTek Computer, Inc.)
• Inventors: Lee, Yuan-Huei, Chang, Chi, Chen, Chia-Hsin, Liu, Ming-Che
• Application Number:
  US12/401,466
• Publication Number:
  US 20090248965A1
• 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 2212/7202 Allocation control and policies
• CPC Class Codes: G06F 2212/7208 Multiple device management, e.g. distributing data over multiple flash devices

Abstract

A hybrid flash memory device and a control method of the hybrid flash memory device are provided. The hybrid flash memory device includes a micro controller connected to a host bus for receiving data to be written in the hybrid flash memory device from a host via the host bus; and a memory module coupled to the micro controller. The flash module includes a first type of flash memory and a second type of flash memory. The data are determined to be written in a first log block of the first type of flash memory when the data size is not greater than a predetermined data size. On the contrary, the data are determined to be written in a second log block of the second type of flash memory when the data size is greater than the predetermined data size.

Claims

1. A hybrid flash memory device comprising:

a micro controller connected to a host bus for receiving data to be written in the hybrid flash memory device from a host via the host bus; and

a memory module coupled to the micro controller and comprising therein a first type of flash memory and a second type of flash memory,

wherein the data are written in a first log block of the first type of flash memory when the data have a size not greater than a predetermined data size, and the data are written in a second log block of the second type of flash memory when the data have a size greater than the predetermined data size.

2. The hybrid flash memory device according to claim 1 wherein the data to be written in the second log block are written in pages including an initial page of the second log block.

3. The hybrid flash memory device according to claim 1 wherein the data to be written in the second log block are merged with previous data stored in at least one page including an initial page, and the merged data are written in the second log block.

4. The hybrid flash memory device according to claim 1 wherein the first type of flash memory is a single level cell NAND flash memory and the second type of flash memory is a multi level cell NAND flash memory.

5. The hybrid flash memory device according to claim 1 wherein the first type of flash memory is a first grade flash memory and the second type of flash memory is a second grade flash memory.

6. The hybrid flash memory device according to claim 1 wherein the hybrid flash memory device is produced as one of a thumb drive, a compact flash device, a secure digital device and a multimedia card device.

7. A method of controlling a hybrid flash memory device comprising a first type of flash memory and a second type of flash memory, the method comprising steps of:

receiving data to be written in the hybrid flash memory device from a host;

writing the data in a first log block of the first type of flash memory when the data have a size not greater than a predetermined data size; and

writing the data in a second log block of the second type of flash memory when the data have a size greater than the predetermined data size.

8. The method according to claim 7 wherein the data to be written in the second log block are written in pages including an initial page of the second log block.

9. The method according to claim 7 wherein the data to be written in the second log block are merged with previous data stored in at least one page including an initial page, and the merged data are written the second log block.

10. The method according to claim 7 wherein the first type of flash memory is a single level cell NAND flash memory and the second type of flash memory is a multi level cell NAND flash memory.

11. The method according to claim 7 wherein the first type of flash memory is a first grade flash memory and the second type of flash memory is a second grade flash memory.

12. The method according to claim 7 wherein the hybrid flash memory device is produced as one of a thumb drive, a compact flash device, a secure digital device and a multimedia card device.