| 摘要 |
PURPOSE:To prevent the resise of the potential of a word line and the double selection by controlling to attenuate with a prescribed time constant the discharge characteristics of the discharge current of the word line which is to be extracted out of the word line when a selection mode is switched to a non- selection mode. CONSTITUTION:The discharge current IDIS is gradually attenuated with the prescribed discharge characteristics since the sudden turn-off of the current IDIS will cause the rerise Q of potential. A word line discharging circuit WDC consists of a dummy cell DC and a transistor TD for the control of a word line discharge current. The base potential V'B of a transistor TME rises up when the rerise Q of potential starts within a memory cell MC which is changed to an NS mode from an S mode. Then a transistor TD is biased deep and continues the extraction f the word line discharge current in response to the potential V'B. In such a way, a practical discharging circuit for the word line is produced with the extraction of the discharge current I''DIS corresponding to the change of V'B.
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