64Mbit – Enhanced SDRAM
8Mx8, 4Mx16 ESDRAM
Preliminary Datasheet
Power Down Modes
Power Down mode is initiated by holding CKE low after all banks are precharged and the required precharge delay (tRP) is
satisfied. In this mode no refresh cycles can occur so the device must not remain in this state longer than the refresh period
(tREF). Power Down mode is exited one clock cycle after bringing CKE high.
Clock Suspend Mode
When CKE is brought low during normal operation, the execution of the current command is suspended until CKE is
clocked high. There is a one clock delay after registration of CKE low before ESDRAM operation is suspended. Clock
Suspend mode is exited one clock cycle after CKE returns high. During a read burst, the last data is held valid until
normal operation resumes. During a write burst, input data is masked and ignored until normal operation resumes.
This is a product in sampling or pre-production phase of development. Charac-
teristic data and other specifications are subject to change without notice.
Enhanced Memory Systems Inc., 1850 Ramtron Dr., Colo Spgs, CO 80921
PHONE: (800) 545-DRAM; FAX: (719) 488-9095; http://www.edram.com
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RAMTRON [ RAMTRON INTERNATIONAL CORPORATION ]
