Coding to decrease error rate discrepancy between pages

A method, comprising:

• operating a memory device using a first unit-distance code that indicates a mapping between a plurality of pages of a memory cell and respective first subsets of a plurality of read voltages;
• receiving a read command to retrieve data from the memory cell, the data associated with a first page from the plurality of pages;
• selecting, from the plurality of read voltages, a second subset of the plurality of read voltages that are associated with the first page according to a second unit-distance code, wherein the second unit-distance code indicates a mapping between the plurality of pages of the memory cell and respective second subsets of the plurality of read voltages;
• and
• retrieving, from the memory cell, the data indicated by the read command based at least in part on applying one or more of the second subset of the plurality of read voltages to the memory cell, wherein a range of average read voltage drifts that each correspond to one of the plurality of pages and is based at least in part on voltage drifts of the read voltages within respective first subsets of the plurality of read voltages indicated by the first unit-distance code is greater than a range of average read voltage drifts that each correspond to one of the plurality of pages and is based at least in part on voltage drifts of the read voltages within respective second subsets of the plurality of read voltages indicated by the second unit-distance code.

A memory system, comprising:

• one or more memory devices comprising a plurality of memory cells, the plurality of memory cells each comprising a plurality of pages;
• and
• processing circuitry coupled with the one or more memory devices and configured to cause the memory system to:
• operate the one or more memory devices using a first unit-distance code that indicates a mapping between the plurality of pages of a memory cell of the plurality of memory cells and respective first subsets of a plurality of read voltages;
• receive a read command to retrieve data from the memory cell of the plurality of memory cells, the data associated with a first page from the plurality of pages;
• select, from the plurality of read voltages, a second subset of the plurality of read voltages that are associated with the first page according to a second unit-distance code, wherein the second unit-distance code indicates a mapping between the plurality of pages of the memory cell and respective second subsets of the plurality of read voltages;
• and
• retrieve, from the memory cell, the data indicated by the read command based at least in part on applying one or more of the second subset of the plurality of read voltages to the memory cell, wherein a range of average read voltage drifts that each correspond to one of the plurality of pages and is based at least in part on voltage drifts of the read voltages within respective first subsets of the plurality of read voltages indicated by the first unit-distance code is greater than a range of average read voltage drifts that each correspond to one of the plurality of pages and is based at least in part on voltage drifts of the read voltages within respective second subsets of the plurality of read voltages indicated by the second unit-distance code.