| 摘要 |
PURPOSE:To hold a word line to a prescribed level even when a refresh cycle is changed and the number of the selecting word line is changed by switching the connection of plural capacitance elements for boosting according to a refresh cycle switching signal. CONSTITUTION:When the refresh cycle switching signal RFS is a high/low level (II/L), the output of an inverter. (IV) 1 is inverted and becomes L/H. Then, when the signal RFS is II, a word active signal WAC is not transmitted to the capacitance element C2 and a word line drive voltage Vwd is boosted by only a capacitance element C1 through the IV 2, 3. Further, when the signal RFS is L, the signal WAC is transmitted to the C2 through NAD gate G1 and the IV4 and the voltage Vwd boosted by the elements C1, C2 is supplied to a word driver circuit 3. Thus, the word line is held to a prescribed level even when the word line selected by the refresh cycle becomes two pieces or four pieces and the efficiency of the read/write of information is improved. |
