A nonvolatile semiconductor memory device obtained by combining a
nonvolatile memory device with a SRAM is provided to improve operating
speed and reliability. The nonvolatile semiconductor memory device
includes a plurality of data registers. Preferably, each of the plurality
of data registers includes a pull-up driving unit adapted and configured
to pull up a storage node, a pull-down driving unit adapted and
configured to pull down the storage node, a data input/output unit
adapted and configured to selectively input and output data between a bit
line and the storage node depending on a voltage applied to a word line,
and a data storing unit adapted and configured to store data of the
storage node depending on a voltage applied to a top word line and a
bottom word line or to output the stored data to the storage node.