A memory device includes memory cell blocks, bit line sense amplifier blocks, and a control circuit connected to one or more of the bit line sense amplifier blocks arranged between the memory cell blocks. The control circuit controls levels of currents respectively supplied to a first sensing driving voltage line and a second sensing driving voltage line driving bit line sense-amplifiers, to be constant. A first sensing driving control signal and/or a second sensing driving control signal, output from the sensing-matching control circuit is provided to the bit line sense amplifiers in all of the bit line sense amplifier blocks, so that the bit line sense amplifiers are constantly driven based on the constant levels of currents supplied to the first sensing driving voltage line and the second sensing driving voltage line.