| 摘要 |
PURPOSE:To reduce testing time substantially by providing a selective nonvolatile memory cell at the time of carrying out a test as well as a using nonvolatile memory cell. CONSTITUTION:A gate in a nonvolatile memory is connected to a word line WD, a drain is connected to either plural number of bit lines B1, B2,..., Bm, and its source is connected to a common grounding power source VSS. When a voltage >=ten-V is impressed to an input terminal 50, a nonvolatile memory cell connected to a word line W2 and that connected to the word line WD are simultaneously selected. However, since the nonvolatile memory cell connected to the word line W2 is in the written condition, only for the nonvolatile memory cell connected to the word line WD writing and reading operations are carried out. The writing process at the time of carrying out a test of a nonvolatile memory is finished by one time; therefore testing time can be shortened substantially. |
