Apparatus and methods for read retry with conditional data refresh

A method comprising:

• first reading a block of non-volatile memory cells using default read levels;
• determining that the first read failed to successfully read the block of non-volatile memory cells;
• re-tuning the first read levels to determine re-tuned read levels each associated with a corresponding default read level;
• second reading the block of non-volatile memory cells using the re-tuned read levels;
• determining a first difference between a first default read level and a corresponding first re-tuned read level;
• predicting based on the first difference that the first read failed because of data retention or read disturb;
• and
• re-writing data to the block of non-volatile memory cells.

Apparatus comprising:

• a plurality of non-volatile memory cells;
• a control circuit coupled to the non-volatile memory cells, the control circuit configured to:
• first read a block of non-volatile memory cells using a first setoff read parameters;
• determine that the first read fails to successfully read the block of non-volatile memory cells;
• second read the block of memory cells using a second set of read parameters different from the first plurality of read levels;
• determine that the second read successfully reads the block of non-volatile memory cells;
• predict that the first read failed because of read disturb;
• and
• re-write data to the block of non-volatile memory cells.