Patent ID: 8874992

Claim:
A method comprising: in a data storage device that includes a non-volatile memory, performing: determining that a current error correction code page count (CEC) value is equal to or larger than a target error correction code page count (TEC) value by comparing the CEC value to the TEC value, wherein the CEC value is a count of error correction code (ECC) pages of data read from the non-volatile memory during a time period from a previous time to a particular time, wherein the data is read using a set of reference voltages; and in response to the CEC value being equal to or larger than the TEC value, updating a subset of the set of reference voltages conditioned upon a difference between a current mean error count (CMEC) and a previous mean error count (PMEC) being at least as large as a target mean delta error (TMDE), wherein the CMEC is based on a count of read errors associated with the data read from the non-volatile memory during the time period.