| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a nonvolatile semiconductor memory device capable of improving the writing efficiency, and to provide its writing method. <P>SOLUTION: The memory device includes: bit lines to which drain areas of a plurality of nonvolatile memory cells in the same column direction are connected in common; and word lines to which gate electrodes of a plurality of nonvolatile memory cells in the same row direction are connected in common, wherein the device further includes: a memory cell array to which source areas of the nonvolatile memory cells in the same column direction are grounded in common; a word line driving circuit for selecting the word line according to a row address signal to apply a voltage to a selected word line; and a writing circuit for creating a writing voltage according to writing data and also selecting the bit line according to a column address signal to apply the writing voltage to a selected bit line. In the writing operation, after predetermined voltages are respectively applied to the drain area and a control gate, the voltage to be applied to the control gate is released. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
