Non-volatile memory device and method for driving the same

A method for driving a non-volatile memory device which includes a memory string and a string selection transistor, the memory string including a plurality of non-volatile memory cells provided between a common source line and a bit line, the string selection transistor provided between the memory string and the common source line, wherein each non-volatile memory cell is coupled to a word line, the method comprising:

• providing a first voltage to the string selection transistor during a precharge operation;
• providing a second voltage to the common source line during the precharge operation;
• applying a word line selection voltage to a selected word line, the selected word line being coupled to one of the non-volatile memory cells;
• and
• precharging the bit line by providing the second voltage to the memory string in response to the first voltage.

A method for precharging a non-volatile memory device having a bit line, a common source line and a memory string that is provided between the bit line and the common source line, the method comprising:

• applying a first voltage to a gate terminal of a string selection transistor, the string selection transistor having first terminal coupled to the memory string and a second terminal coupled to the common source line;
• applying a second voltage to the second terminal of the string selection transistor via the common source line;
• and
• applying a word line selection voltage to a selected word line coupled to a gate terminal of a memory cell, the word line selection voltage having a voltage level sufficient to turn on the memory cell if the memory cell is a first state but insufficient to turn on the memory cell if the memory cell is in a second state,
• wherein the bit line is precharged if the memory cell is in the first state and not precharged if the memory cell is in the second state.