SEMICONDUCTOR MEMORY DEVICE, AND METHOD FOR CONTROLLING REFRESHING OF SEMICONDUCTOR MEMORY DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor memory device in which current consumption in a standby state is reduced by a preferable sampling refresh-function and a method for controlling refreshing. SOLUTION: When a sampling refresh-function is added while refresh- operation and external access operation are performed independently, a refresh- address Add(C) is outputted from a refresh-address counter 12, the prescribed high-order bits out of the above are inputted to a sampling refresh-control circuit 1 as a high-order refresh-address Add(C)(m), and whether refresh- operation is to be executed or not is determined. A refresh-execution permission signal RFEN being a determination result is inputted to a word driver 18, and activation control of the word driver 18 is preformed. Determination processing by the sampling refresh-control circuit 1 can be incorporated in an access time of a row system. COPYRIGHT: (C)2003,JPO