SEMICONDUCTOR MEMORY DEVICE

PURPOSE:To reduce power consumption by so forming the titled device that only the word line in a memory mat selected by an X-address decoder which selectively acts, is made in selective state. CONSTITUTION:The internal complementary address signal formed in accordance with an address signal AX which is in synchronization with a raw address strobing signal RAS is selectively supplied to raw address decoders R-DCR 1 and R-DCR 2 via a multiplexer MPX. The DCR 1(2) forms a selecting signal for the word line in accordance with an address signal for refreshing from a circuit REF or with an address signal. By this selecting action, only the one of the DCRs 1 and 2 that actually executes the word-line-selecting action for reading/writing complying with an address signal for mat-changeover, is actuated. Either of the DCRs 1 or 2 that is made in active state by the address signal for changeover, selects the word line in synchronization with a word-line selecting timing signal phix.