Method and apparatus for using a one-time or few-time programmable memory with a host device designed for erasable/rewriteable memory

• US 20070208907A1
• Filed: 04/27/2007
• Published: 09/06/2007
• Est. Priority Date: 08/24/2004
• Status: Active Grant

• Current Assignee: SanDisk Technologies LLC (Western Digital Corporation)
• Original Assignee: Adrian Jeday, Chia Yang, Christopher Moore, Derek Bosch, Matt Fruin
• Inventors: Jeday, Adrian, Bosch, Derek, Fruin, Matt, Moore, Christopher, Yang, Chia
• Granted Patent: US 7,861,058 B2
• Time in Patent Office: Days
• US Class Current: 711/103
• CPC Class Codes: G06F 11/1068 in sector programmable memories, e.g. flash disk G06F11/1072 takes precedence
• CPC Class Codes: G06F 12/0238 Memory management in non-volatile memory, e.g. resistive RAM or ferroelectric memory
• CPC Class Codes: G06F 2212/1032 Reliability improvement, data loss prevention, degraded operation etc
• CPC Class Codes: G06F 2212/1036 Life time enhancement
• CPC Class Codes: G06F 2212/2142 using write-once memory, e.g. OTPROM
• CPC Class Codes: G06F 2212/7201 Logical to physical mapping or translation of blocks or pages
• CPC Class Codes: G06F 2212/7207 management of metadata or control data
• CPC Class Codes: G06F 3/0607 by facilitating the process of upgrading existing storage systems, e.g. for improving compatibility between host and storage device
• CPC Class Codes: G06F 3/0661 Format or protocol conversion arrangements
• CPC Class Codes: G06F 3/0679 Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]
• CPC Class Codes: G06F 3/08 from or to individual record carriers, e.g. punched card , memory card, integrated circuit [IC] card or smart card

Abstract

The embodiments described herein can be used to enable one-time or few-time programmable memories to work with existing consumer electronic devices (such as those that work with flash—an erasable, non-volatile memory) without requiring a firmware upgrade, thereby providing backwards compatibility while minimizing user impact. As such, these embodiments are a viable way to bridge one-time or few-time programmable memories with existing consumer electronic devices that have flash card slots. These embodiments also allow future consumer electronic devices to be designed without updating firmware to include a file system customized for a one-time or few-time programmable memory.

Claims

1. A memory device comprising:

a memory array, wherein the memory array is organized into logical units that can be partially written into, whereby multiple write operations can be performed to each logical unit before the logic unit is full; and

a controller in communication with the memory array, wherein the controller is operative to write ECC data for a logical unit when a last write operation is made to the logical unit.

2. The memory device of claim 1, wherein the controller is operative to write ECC data for a logical unit only when a last write operation is made to the logical unit.

3. The memory device of claim 1, wherein the controller is operative to write ECC data for a logical unit both when a first write operation is made to the logical unit and when a last write operation is made to the logical unit.

4. The memory device of claim 1, wherein the controller is operative to write ECC data for a logical unit when a last two bytes are written to the logical unit.

5. The memory device of claim 1, wherein the controller is operative to write ECC data for a logical unit when a last six bytes are written to the logical unit.

6. The memory device of claim 1, wherein the controller is further operative to perform a remap operation in response to an ECC word being invalid.

7. The memory device of claim 1, wherein the memory array comprises a one-time programmable memory array.

8. The memory device of claim 1, wherein the memory array comprises a few-time programmable memory array.

9. The memory device of claim 1, wherein the memory array comprises a three-dimensional memory array.