A sense amplifier includes a first sense amplification circuit electrically connected between a bit line, to which a multi-bit memory cell is also connected, and a complementary bit line. The first sense amplification circuit is configured to sense a least significant bit (LSB) of 2-bit data in the memory cell and latch the LSB in a first sensing bit line pair. A second sense amplification circuit is provided, which is configured to sense a most significant bit (MSB) of the 2-bit data and latch the MSB in a second sensing bit line pair. A switching circuit is provided, which is configured to selectively connect between bit lines of the first sensing bit line pair and bit lines of the second sensing bit line pair.