JPS6457488A - Dynamic type ram - Google Patents

Abstract

PURPOSE:To highly accurately offset the coupling noise of a data line, by disposing plural dummy word lines correspondingly to plural word lines assigned to the decoder of a unit and using plural word line selecting timing signals as selecting signals thereof. CONSTITUTION:As the dummy word line for offsetting the coupling of the word lines W0-W3 and the data lines D, the inverse of D through a memory cell, the plural dummy word lines DW0-DW3 are disposed correspondingly to the plural word lines assigned to the decoder of the unit and as the selecting signal, the plural word line selecting timing signals supplied to the decoder UDCR of the unit are used. Accordingly, the word lines and the dummy word lines can be controlled by the same selecting timing signal. Thereby, the coupling noise appearing on the data line can be offset at high accuracy to increase the level margin of a reading signal from the memory cell.