A memory device includes a memory cell array that includes memory cells, a row decoder that is connected with the memory cell array through word lines, a column decoder that is connected with the memory cell array through bit lines and source lines, and a write driver that outputs a write voltage in a write operation. The column decoder includes switches, which are respectively connected to the bit lines and are respectively connected to the source lines. During the write operation, a selected switch of the switches transfers the write voltage to a selected bit line of the bit lines. Each unselected switch of the switches electrically separates the write driver from a corresponding unselected bit line of the bit lines by using the write voltage.