Multi-Level Cell Flash Memory Control Mechanisms
First Claim
1. A method, in multi-layer cell (MLC) flash memory device comprising a MLC flash memory and a controller, for controlling an operation of the MLC flash memory device, the method comprising:
- controlling, by the controller, accesses to a block of memory pages in the MLC flash memory to be performed to the full block of memory pages in a MLC mode of operation;
determining, by the controller, whether a MLC retirement threshold has been met or exceeded by an operating characteristic of the block of memory pages;
switching, by the controller, in response to detecting that the operating characteristic of the block of memory pages has met or exceeded the MLC retirement threshold, an operating mode associated with the block of memory pages from the MLC mode of operation to a single-level cell (SLC) mode of operation in which a sub-set of pages of the block of memory pages are utilized for access operations; and
controlling, by the controller, access operations to the block of memory pages in accordance with the SLC mode of operation in response to switching the operating mode of the block of memory pages from the MLC mode of operation to the SLC mode of operation.
1 Assignment
0 Petitions
Accused Products
Abstract
Mechanisms are provided, in multi-layer cell (MLC) flash memory device comprising a MLC flash memory and a controller, for controlling an operation of the MLC flash memory device. The controller controls accesses to a block of memory pages in the MLC flash memory to be performed to the full block of memory pages in a MLC mode of operation. The controller determines whether a MLC retirement threshold has been met or exceeded by an operating characteristic of the block of memory pages. The controller, in response to detecting that the operating characteristic of the block of memory pages has met or exceeded the MLC retirement threshold, switches an operating mode associated with the block of memory pages from the MLC mode of operation to a single-level cell (SLC) mode of operation. The controller enforces the SLC mode of operation when performing access operations to the block of memory pages.
76 Citations
20 Claims
-
1. A method, in multi-layer cell (MLC) flash memory device comprising a MLC flash memory and a controller, for controlling an operation of the MLC flash memory device, the method comprising:
-
controlling, by the controller, accesses to a block of memory pages in the MLC flash memory to be performed to the full block of memory pages in a MLC mode of operation; determining, by the controller, whether a MLC retirement threshold has been met or exceeded by an operating characteristic of the block of memory pages; switching, by the controller, in response to detecting that the operating characteristic of the block of memory pages has met or exceeded the MLC retirement threshold, an operating mode associated with the block of memory pages from the MLC mode of operation to a single-level cell (SLC) mode of operation in which a sub-set of pages of the block of memory pages are utilized for access operations; and controlling, by the controller, access operations to the block of memory pages in accordance with the SLC mode of operation in response to switching the operating mode of the block of memory pages from the MLC mode of operation to the SLC mode of operation. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A computer program product comprising a computer readable storage medium having a computer readable program stored therein, wherein the computer readable program, when executed by a controller of a multi-layer cell (MLC) flash memory device, causes the controller to:
-
control accesses to a block of memory pages in the MLC flash memory to be performed to the full block of memory pages in a MLC mode of operation; determine whether a MLC retirement threshold has been met or exceeded by an operating characteristic of the block of memory pages; switch, in response to detecting that the operating characteristic of the block of memory pages has met or exceeded the MLC retirement threshold, an operating mode associated with the block of memory pages from the MLC mode of operation to a single-level cell (SLC) mode of operation in which a sub-set of pages of the block of memory pages are utilized for access operations; and control access operations to the block of memory pages in accordance with the SLC mode of operation in response to switching the operating mode of the block of memory pages from the MLC mode of operation to the SLC mode of operation. - View Dependent Claims (12, 13, 14, 15, 16, 17, 18, 19)
-
-
20. An apparatus comprising:
-
a multi-layer cell (MLC) flash memory; and a controller coupled to the MLC flash memory, wherein the controller comprises logic configured to cause the controller to; control accesses to a block of memory pages in the MLC flash memory to be performed to the full block of memory pages in a MLC mode of operation; determine whether a MLC retirement threshold has been met or exceeded by an operating characteristic of the block of memory pages; switch, in response to detecting that the operating characteristic of the block of memory pages has met or exceeded the MLC retirement threshold, an operating mode associated with the block of memory pages from the MLC mode of operation to a single-level cell (SLC) mode of operation in which a sub-set of pages of the block of memory pages are utilized for access operations; and control access operations to the block of memory pages in accordance with the SLC mode of operation in response to switching the operating mode of the block of memory pages from the MLC mode of operation to the SLC mode of operation.
-
Specification