| 摘要 |
<p>PURPOSE:To restrict a parasitic thyristor effect and perform a stable writing operation by impressing a high voltage generated in a writing terminal during writing to a non-selected word line. CONSTITUTION:By connecting a restricted voltage impressing circuit 12 to a writing terminal,an electric potential of a word line in a non-selected condition is raised above the potential of a digit line. Accordingly, a circuit 12 operates, but since in resistances R1M, R2M a high resistance is selected, an electric current scarcely flows, a lowering of a voltage becomes a sum of a voltage between a collector and an emitter of a pnp FET Q1M, a voltage between the emitter and a base of an npn FET Q2M, a forward direction voltage of a diode D1M, a word line W1 has a high voltage, and an operation of a parasitic thyristor comprising a written cell and a writing cell in the same word line W1 can be prevented.</p> |
