SEMICONDUCTOR MEMORY DEVICE, INTERNAL REFRESH STOP METHOD, COMPETITION PROCESSING METHOD OF EXTERNAL ACCESS AND INTERNAL REFRESH,COUNTER INITIALIZING METHOD, REFRESH ADDRESS DETECTING METHOD OF EXTERNAL REFRESH, AND EXECUTION SELECTING METHOD OF EXTERNAL REFRESH

摘要

PROBLEM TO BE SOLVED: To achieve a semiconductor memory device which can arbitrate the competition of various external access and internal simultaneous refresh without regarding to an internal refresh word line address by a system side, on which the semiconductor memory device using no memory bank constitution is mounted with a small footprint. SOLUTION: A refresh block counter is composed of counters of two systems of an increment counter 360 and a decrement counter 370. The semiconductor memory device includes a refresh counter control circuit 350. The refresh counter control circuit 350 stops refresh access for a corresponding block when an address of the increment counter 360 or an address the decrement counter 370 and an external access block address are coincident. When the value of the increment counter 360 becomes larger than the value of the decrement counter 370, refresh and count-up operation are stopped. COPYRIGHT: (C)2009,JPO&INPIT