System and method of page buffer operation for memory devices

• US 20080209108A1
• Filed: 07/06/2007
• Published: 08/28/2008
• Est. Priority Date: 02/22/2007
• Status: Active Grant

• Current Assignee: Conversant Intellectual Property Management Inc (MOSAID Technologies Inc. (f/k/a Conversant Intellectual Property Management))
• Original Assignee: MOSAID Technologies Inc. (f/k/a Conversant Intellectual Property Management)
• Inventors: Kim, Jin-Ki, Oh, HakJune, Pyeon, Hong Beom
• Granted Patent: US 8,086,785 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 12/0893 Caches characterised by their organisation or structure
• CPC Class Codes: G06F 2212/1044 Space efficiency improvement
• CPC Class Codes: G06F 2212/2022 Flash memory
• CPC Class Codes: G06F 2212/3042 being part of a memory device, e.g. cache DRAM
• CPC Class Codes: G06F 2212/7203 Temporary buffering, e.g. using volatile buffer or dedicated buffer blocks
• CPC Class Codes: G06F 2212/7208 Multiple device management, e.g. distributing data over multiple flash devices
• CPC Class Codes: G11C 2207/2245 Memory devices with an internal cache buffer
• CPC Class Codes: G11C 7/1039 using pipelining techniques, i.e. using latches between functional memory parts, e.g. row/column decoders, I/O buffers, sense amplifiers
• CPC Class Codes: G11C 7/106 Data output latches
• CPC Class Codes: G11C 7/1087 Data input latches

Abstract

Systems and methods are provided for using page buffers of memory devices connected to a memory controller through a common bus. A page buffer of a memory device is used as a temporary cache for data which is written to the memory cells of the memory device. This can allow the memory controller to use memory devices as temporary caches so that the memory controller can free up space in its own memory.

Claims

1. A method for controlling a memory device connected with a controller, the device having a page buffer and memory cells, the controller having a data storage, the method comprising:

writing data from the data storage of the controller to the page buffer of the device; and

reading back the data at a later time from the page buffer of the device to the data storage of the controller, before programming the data from the page buffer into the memory cells of the device.

2. The method of claim 1 wherein the step of writing comprises:

enabling the device;

providing a data load command and data to the device, the data being transmitted from the data storage of the controller; and

providing a command strobe to the device,

the page buffer of the enabled device storing the data in the page buffer thereof in response to the data load command and the command strobe.

3. The method of claim 1 further comprising:

freeing up space in the data storage where the data is occupied, upon writing the data from the data storage of the controller to the page buffer of the device.

4. The method of claim 1 wherein the step of reading back comprises:

enabling the device;

providing a data strobe to the device,

the data stored in the page buffer of the enabled device being outputted to the data storage of the controller in response to the data strobe.

5. A method for controlling a plurality of devices connected with a controller through a common bus, each of the devices having a page buffer and memory cells, the controller having a data storage, the method comprising:

writing data from the data storage of the controller to the page buffer of a designated device; and

reading back the data at a later time from the page buffer of the designated device to the data storage of the controller, before programming the data from the page buffer into the memory cells of the designated device.

6. The method of claim 5 further comprising:

freeing up space in the data storage where the data is occupied, upon writing the data from the data storage of the controller to the page buffer of the designated device.

7. The method of claim 6 wherein the step of writing comprises:

designating one device of the plurality of devices to enable it;

providing a data load command and data to the device, the data being transmitted from the data storage of the controller; and

providing a command strobe to the device,

the page buffer of the enabled device storing the data in the page buffer thereof in response to the data load command and the command strobe.

8. The method of claim 6 wherein the step of reading back comprises:

enabling the designated device;

providing a data strobe to the designated device,

the data stored in the page buffer of the designated device being outputted to the data storage of the controller in response to the data strobe.

9. The method of claim 5 wherein the step of writing comprises:

enabling first and second devices of the plurality of devices inclusive of said designated device;

providing a data load command and data to the first and second devices, the data being transmitted from the data storage of the controller; and

providing a command strobe to the first and second devices;

the page buffers of the first and second devices storing the data in the page buffer thereof in response to the data load command and the command strobe.

10. The method of claim 9 wherein the step of providing a data load and data comprises:

providing first data load and data and second data load and data.

11. The method of claim 10 wherein the step of providing first data load and data and second data load and data comprises:

providing the first and second data load simultaneously,

the page buffers of the first and second devices storing the data.

12. The method of claim 10 wherein the step of providing first data load and data and second data load and data comprises:

providing the first data load and first data and the second data load and second data in different timing,

the page buffers of the first and second devices storing the first and second data, respectively.

13. The method of claim 11 wherein the step of reading back comprises:

enabling the designated device of the first and second devices;

providing a data strobe to the designated device, and

the data stored in the page buffer of the enabled and designated device being outputted to the data storage of the controller in response to the data strobe.

14. The method of claim 12 wherein the step of reading back comprises:

enabling the designated device of the first and second devices;

providing a data strobe; and

the data stored in the page buffer of the enabled and designated device being outputted to the data storage of the controller in response to the data strobe.

15. An apparatus for controlling a plurality of devices connected with a common bus, each of the devices having a page buffer and memory cells, the apparatus having a data storage, the apparatus being capable of:

writing data from the data storage to the page buffer of a designated device; and

reading back the data at a later time from the page buffer of the designated device to the data storage, before programming the data from the page buffer into the memory cells of the designated device.

16. The apparatus of claim 15 being further capable of:

freeing up space in the data storage where the data is occupied, upon writing the data from the data storage to the page buffer of the designated device.

17. A system comprising:

a plurality of devices connected with a common bus, each of the devices having a page buffer and memory cells; and

a memory controller for controlling the plurality of devices, the memory controller being capable of;

writing data from a data storage of the controller to the page buffer of a designated device; and

reading back the data at a later time from the page buffer of the designated device to the data storage of the controller, before programming the data from the page buffer into the memory cells of the designated device.

18. The system of claim 17 wherein the memory controller is further capable of:

freeing up space in the data storage where the data is occupied, upon writing the data from the data storage of the controller to the page buffer of the designated device.

19. The system of claim 17 wherein each device of the plurality of devices comprises a flash memory device.

20. The system of claim 19 wherein each flash memory device comprises a NAND flash device.