Nonvolatile method device and sensing method of the same

A sensing method of a nonvolatile memory device comprising a plurality of multi-level cells, the method comprising:

• precharging a bit line of a selected memory cell and a sense-out node connected to the bit line;
• applying a first sensing voltage to a selected word line where the selected memory cell is located;
• developing the sense-out node during a develop interval;
• and
• sensing the sense-out node multiple times during the develop interval,
• wherein the sensing the sense-out node multiple times comprises:
• identifying a first state of the selected memory cell by sensing a first voltage level of the sense-out node at a first sensing point in the develop interval;
• and
• identifying a second state of the selected memory cell by sensing a second voltage level of the sense-out node at a second sensing point after the first sensing point,
• wherein the second state is a program state adjacent to the first state.

A sensing method of a nonvolatile memory device comprising a plurality of multi-level cells and being configured to perform a plurality of sensing loops of a selected memory cell connected to a selected word line, the sensing method, performed by at least one sensing loop among the plurality of sensing loops, comprising:

• precharging a bit line connected to the selected memory cell during a first precharge interval;
• precharging a sense-out node connected to the bit line to a first sense-out precharge voltage during the first precharge interval;
• developing the sense-out node during a develop time;
• sensing an ith program state (i is an integer) of the selected memory cell by sensing a first voltage level of the sense-out node during a first sensing interval;
• precharging the sense-out node to a second sense-out precharge voltage during a second precharge interval;
• developing the sense-out node for a period longer than the develop time by a change amount in the develop time;
• and
• sensing an (i+1)th program state of the selected memory cell by sensing a second voltage level of the sense-out node during a second sensing interval.