Patent ID: 8154948

Claim:
A method of operating a nonvolatile memory device, comprising: providing page buffers each coupled to one or more bit lines; supplying a variable voltage of a first voltage level to a selected page buffer among the page buffers and supplying the variable voltage to a first bit line, coupled to a selected memory cell selected for data reading, for a first time period; cutting off the supply of the variable voltage to the first bit line, after the first time period, and precharging the first bit line to a second voltage level through a sense node of the selected page buffer, which is in a precharge state; evaluating a voltage of the first bit line, after the precharging of the first bit line, so that the voltage of the first bit line is shifted according to a program state of the selected memory cell; and sensing the voltage of the first bit line, after the evaluating of the voltage of the first bit line, and latching data in the selected memory cell.