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512Mb: x4, x8, x16 DDR SDRAM
512Mx4x8x16DDR_B.p65
–
Rev. B; Pub 4/01
Micron Technology, Inc., reserves the right to change products or specifications without notice.
2001, Micron Technology, Inc.
512Mb: x4, x8, x16
DDR SDRAM
ADVANCE
Figure 13
READ to PRECHARGE
CK
CK#
COMMAND
6
READ
NOP
PRE
NOP
NOP
ACT
ADDRESS
Bank
a
,
Col
n
Bank
a
,
(
a
or
all
)
Bank
a
,
Row
READ
NOP
PRE
NOP
NOP
ACT
Bank
a
,
Col
n
CL = 2
tRP
tRP
NOTE
: 1. DO
n
= data-out from column
n
.
2. Burst length = 4, or an interrupted burst of 8.
3. Three subsequent elements of data-out appear in the programmed order following DO
n
.
4. Shown with nominal tAC, tDQSCK, and tDQSQ.
5. READ to PRECHARGE equals two clocks, which allows two data pairs of data-out.
6. A READ command with AUTO-PRECHARGE enabled would cause a precharge to be performed
at x number of clock cycles after the READ command, where x = BL / 2.
7. PRE = PRECHARGE command; ACT = ACTIVE command.
CK
CK#
COMMAND
6
ADDRESS
DQ
DQS
CL = 2.5
DQ
DQS
DO
n
DO
n
T0
T1
T2
T3
T2n
T3n
T4
T5
T0
T1
T2
T3
T2n
T3n
T4
T5
Bank
a
,
(
a
or
all
)
Bank
a
,
Row
DON
’
T CARE
TRANSITIONING DATA