Electronic system and refresh method

摘要

An electronic system having a plurality of dynamic semiconductor memory devices and a refresh method for the same. The system comprises a plurality of dynamic semiconductor memory devices and a controller. Each of the dynamic semiconductor memory devices includes a storage device for storing a designated number designating an order for performing a refresh operation, a refresh enable signal generating circuit for generating a refresh enable signal in response to a refresh control command supplied from the controller and a delaying circuit for delaying the refresh enable signal by different time intervals determined by the designated number.