HYB25D256[16/40/80]0C[E/C/F/T](L)
256 Mbit Double-Data-Rate SDRAM
Functional Description
T1
CK
CK
Command
Write
T2
T3
T4
T5
T6
NOP
NOP
NOP
Read
NOP
t
WTR
Address
BAa, COL b
BAa, COL n
t
DQSS
(nom)
DQS
DQ
DM
DI a-b
CL = 2
1
1
DI a-b = data in for bank a, column b.
An interrupted burst is shown, 4 data elements are written.
3 subsequent elements of data in are applied in the programmed order following DI a-b.
t
WTR
is referenced from the first positive CK edge after the last desired data in pair.
The Read command masks the last 2 data elements in the burst.
A10 is Low with the Write command (Auto Precharge is disabled).
The Read and Write commands are not necessarily to the same bank.
1 = These bits are incorrectly written into the memory array if DM is low.
Don鈥檛 Care
Figure 25
Write to Read: Nominal DQSS, Interrupting (CAS Latency = 2; Burst Length = 8)
Data Sheet
50
Rev. 1.6, 2004-12