Memory device and method for estimating characteristics of multi-bit programming

A device comprising:

• a multi-bit cell array;
• and
• a controller configured to estimate a first threshold voltage change of a plurality of threshold voltage states corresponding to data stored in the multi-bit cell array based on a second threshold voltage change of at least one reference threshold voltage state selected from the plurality of threshold voltage states,
• wherein the second threshold voltage change is based on a difference between a threshold voltage when data is programmed and a threshold voltage after a passage of an amount of time from when the data is programmed.

A device comprising:

• a multi-bit cell array;
• and
• a detection unit configured to extract data stored in the multi-bit cells using read voltage levels of a plurality of threshold voltage states corresponding to the data stored in the multi-bit cell array,
• wherein the detection unit is configured to adjust the read voltage levels of the plurality of threshold voltage states based on a threshold voltage change of at least one reference threshold voltage state selected from the plurality of threshold voltage states, the threshold voltage change being based on a difference between a threshold voltage when data is programmed and a threshold voltage after a passage of an amount of time from when the data is programmed.

An operating method of a memory device, the method comprising:

• extracting a first threshold voltage change of at least one reference threshold voltage state from a plurality of threshold voltage states stored in a multi-bit cell array;
• sending the first threshold voltage change to a estimation unit;
• estimating second threshold voltage changes of the plurality of threshold voltage states based on the received threshold voltage change;
• reading data from the multi-bit cell array based on the estimated second threshold voltage changes.