Voltage generation circuit and nonvolatile memory device using the same

A voltage generation circuit, comprising:

• a first signal output unit configured to generate a first voltage level determination signal having a fixed data value;
• a second signal output unit configured to output a second voltage level determination signal having a varying data value;
• a selection unit configured to output one of the first and second voltage level determination signals in response to a selection signal;
• and
• a voltage generation unit configured to output a voltage having a single pulse form or a voltage having a pulse form whose rising edge portion rises in incremental voltage steps in response to the voltage level determination signal outputted from the selection unit.

A nonvolatile memory device, comprising:

• a bit line coupling unit configured to couple memory cells to a bit line of a cell string;
• a precharge unit configured to precharge a sense node;
• a sense unit coupled between the bit line coupling unit and the precharge unit;
• a latch unit coupled to the sense node;
• and
• a voltage generation circuit configured to output a first sense voltage having a single pulse form or a second sense voltage having a pulse form whose rising edge portion rises in incremental voltage steps to the sense unit,
• wherein the voltage generation circuit is configured to output the second sense voltage during an operation for precharging the bit line.