US 10,891,063 B2
Apparatus and methods for managing data storage among groups of memory cells of multiple reliability ranks
Carla L. Christensen, Boise, ID (US); Avani F. Trivedi, Eagle, ID (US); and Tracy D. Evans, Boise, ID (US)
Assigned to Micron Technology, Inc., Boise, ID (US)
Filed by MICRON TECHNOLOGY, INC., Boise, ID (US)
Filed on Nov. 28, 2018, as Appl. No. 16/202,219.
Prior Publication US 2020/0167087 A1, May 28, 2020
Int. Cl. G06F 3/06 (2006.01); G11C 16/04 (2006.01); G11C 11/56 (2006.01); G11C 16/08 (2006.01)
CPC G06F 3/0631 (2013.01) [G06F 3/0604 (2013.01); G06F 3/0679 (2013.01); G11C 11/5621 (2013.01); G11C 11/5671 (2013.01); G11C 16/0483 (2013.01); G11C 16/08 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method of operating an electronic system, comprising:
allocating a group of memory cells of a particular plurality of groups of memory cells having a particular rank of a plurality of ranks for storing data of a particular data level of a plurality of data levels, wherein each rank of the plurality of ranks is indicative of characteristics of a respective plurality of groups of memory cells regarding its determined ability to retain data at a plurality of different storage densities;
determining a need for an additional group of memory cells for storing data of the particular data level;
moving or discarding data from a different group of memory cells storing data of a different data level of the plurality of data levels in response to determining the need for the additional group of memory cells for storing data of the particular data level; and
allocating the different group of memory cells for storing data of the particular data level;
wherein each data level of the plurality of data levels corresponds to a respective target reliability level,
wherein the respective target reliability level for any data level of the plurality of data levels is different than the respective target reliability level of each remaining data level of the plurality of data levels; and
wherein, for each rank of the plurality of ranks whose respective plurality of groups of memory cells has a determined ability to retain data of two or more data levels of the plurality of data levels, the determined ability of its respective plurality of groups of memory cells to retain data for each data level of its two or more data levels is greater than or equal to the respective target reliability level for that data level of its two or more data levels for at least one storage density of the plurality of different storage densities.