Volatile memory device and data sensing method thereof

A data sensing method of a volatile memory device, the data sensing method comprising:

• precharging a first bit line using a first precharge voltage;
• sensing first 2-bit data through a first sense amplifier connected to the first bit line, the first 2-bit data being stored in a first memory cell connected between the first bit line and a selected word line;
• precharging a second bit line using a second precharge voltage different from the first precharge voltage, the second bit line having a length greater than a length of the first bit line;
• and
• sensing second 2-bit data through a second sense amplifier connected to the second bit line, the second 2-bit data being stored in a second memory cell connected between the second bit line and the selected word line.

A data sensing method of a memory device comprising volatile memory cells storing single-bit data, the data sensing method comprising:

• precharging a first bit line with a first precharge voltage in a sensing operation on a first memory cell connected to the first bit line having a first length;
• sensing first 1-bit data stored in the first memory cell;
• precharging a second bit line with a second precharge voltage in a sensing operation on a second memory cell connected to the second bit line having a second length that is greater than the first length;
• and
• sensing second 1-bit data stored in the second memory cell.