Data storage device and method for managing a hot count difference in sub-block mode
A block of memory in a data storage device can be partitioned into two or more sub-blocks, where each sub-block is independent of the other sub-blocks. If the program-erase counts of the sub-blocks are sufficiently low, the same programming voltage can be used to program each of the sub-blocks. However, for higher program-erase counts, disturb effects can create issues in using the same programming voltage. With the embodiments presented herein, the programming voltage of a given sub-block can be based on the program-erase count of the sub-block. This can avoid the need to compare program-erase counts of various sub-blocks and perform a relocation operation.
1 . A data storage device comprising:
a memory comprising a block configured to be partitioned into two or more sub-blocks; and
one or more processors, individually or in combination, configured to:
determine whether a program-erase count of each sub-block exceeds a threshold;
in response to determining that the program-erase count of each sub-block does not exceed the threshold, use a same programming voltage to program each sub-block; and
in response to determining that the program-erase count of each sub-block exceeds the threshold, use an adaptive programming voltage to program each sub-block by, for each sub-block;
determining a program-erase count of the sub-block;
determining a programming voltage for the sub-block based on the program-erase count of the sub-block; and
programming the sub-block using the programming voltage determined for the sub-block.
2 . The data storage device of claim 1 , wherein the programming voltage for the sub-block is determined from a data structure that associates a plurality of program-erase counts with a respective plurality of programming voltages.
3 . The data storage device of claim 1 , wherein the one or more processors, individually or in combination, are further configured to avoid both comparing program-erase counts between two sub-blocks of the two or more sub-blocks and performing unselected-sub-block-disturb (USBD) relocation handling.
4 . The data storage device of claim 1 , wherein the one or more processors, individually or in combination, are further configured to partition the block of memory into the two or more sub-blocks.
5 . The data storage device of claim 1 , wherein each sub-block of the two or more sub-blocks occupies a single x-y location but is located in a different z location.
6 . The data storage device of claim 1 , wherein each sub-block of the two or more sub-blocks is connected vertically to a same memory hole.
7 . The data storage device of claim 1 , wherein each sub-block of the two or more sub-blocks comprises its own wordline zone.
8 . The data storage device of claim 1 , wherein each sub-block of the two or more sub-blocks operates independently of other sub-blocks of the two or more sub-blocks.
9 . The data storage device of claim 1 , wherein the block is a single-level cell (SLC) block.
10 . The data storage device of claim 1 , wherein the memory comprises a three-dimensional memory.
11 . In a data storage device comprising a memory comprising a block that comprises two or more sub-blocks, a method comprising:
determining whether a hot count of each sub-block exceeds a threshold;
in response to determining that the hot count of each sub-block does not exceed the threshold, using a same programming voltage to program each sub-block; and
in response to determining that the hot count of each sub-block exceeds the threshold, using an adaptive programming voltage to program each sub-block by, for each sub-block:
determining a hot count of the sub-block;
determining a changing an adaptive programming programing voltage to a level for the sub-block based on the hot count of the sub-block; and
programming the sub-block using the programming voltage determined for the sub-block.
12 . The method of claim 11 , wherein a data structure stores an association of programming voltages and hot counts.
13 . The method of claim 11 , further comprising avoiding both comparing hot counts between two sub-blocks of the two or more sub-blocks and performing unselected-sub-block-disturb (USBD) relocation handling.
14 . The method of claim 11 , wherein each sub-block of the two or more sub-blocks occupies a single x-y location but is located in a different z location.
15 . The method of claim 11 , wherein each sub-block of the two or more sub-blocks is connected vertically to a same memory hole.
16 . The method of claim 11 , wherein each sub-block of the two or more sub-blocks comprises its own wordline zone.
17 . The method of claim 11 , wherein each sub-block of the two or more sub-blocks operates independently of other sub-blocks of the two or more sub-blocks.
18 . The method of claim 11 , wherein the memory comprises a three-dimensional memory.
19 . A data storage device comprising:
a memory comprising a plurality of sub-blocks; and
means for:
determining whether a program-erase count of each sub-block exceeds a threshold;
in response to determining that the program-erase count of each sub-block does not exceed the threshold, using a same programming voltage to program each sub-block; and
in response to determining that the program-erase count of each sub-block exceeds the threshold, using an adaptive programming voltage to program each sub-block by, for each sub-block:
determining a program-erase count of the sub-block;
determining a programming voltage for the sub-block based on the program-erase count of the sub-block; and
programming the sub-block using the programming voltage determined for the sub-block.