Reading memory cells using multiple thresholds

A data storage apparatus, comprising:

• an interface, which is operative to communicate with a memory that includes a plurality of analog memory cells;
• and
• a memory signal processor (MSP), which is connected to the interface and is coupled to store data, which is encoded with an Error Correction Code (ECC), in the analog memory cells by writing respective input analog values that program the analog memory cells to a set of memory states, to read the stored data multiple times from each analog memory cell by performing multiple read operations that compare analog output values of the analog memory cells to different, respective read thresholds so as to produce multiple comparison results for each of the analog memory cells, wherein the analog output values associated with each memory state lie in a respective analog value region, wherein analog value regions are separated by one or more boundary regions, and wherein at least two of the read thresholds are positioned in a boundary region between a pair of, to compute soft metrics responsively to the multiple comparison results, and to decode the ECC using the soft metrics, so as to extract the data stored in the analog memory cells.

A data storage apparatus, comprising:

• an interface, which is operative to communicate with a memory that includes a plurality of analog memory cells;
• and
• a memory signal processor (MSP), which is connected to the interface and is coupled to store data, which is encoded with an Error Correction Code (ECC), in a group of analog memory cells of the memory by writing to the analog memory cells in the group respective analog input values, to read the data from the analog memory cells in the group by comparing analog output values of the analog memory cells in the group to one or more read thresholds, and applying ECC decoding to the read data, and, upon a failure of the ECC decoding, to cancel interference caused to the analog memory cells in the group by at least one other analog memory cell, and to re-decode the ECC.