W632GG6KB
Publication Release Date: Jan. 03, 2017
Revision: A06
- 32 -
TIME BREAK
DON'T CARE
CK#
*5
ODT
Command
Diff_DQS
*4
Prime DQ
*1
One Prime DQ:
Late Remaining DQs
Early Remaining DQs
Late Prime DQs
*1
Early Prime DQs
*1
All DQs are Prime:
MRS
*2
NOP
*3
NOP
NOP
NOP
NOP
NOP
NOP
NOP
NOP
NOP
NOP
t
MOD
t
WLDQSEN
t
WLMRD
t
WLMRD
t
DQSL
*6
t
DQSH
*6
t
DQSL
*6
t
DQSH
*6
t
WLO
t
WLO
t
WLOE
t
WLO
t
WLO
t
WLOE
t
WLO
t
WLOE
t
WLO
t
WLO
t
WLO
T1
t
WLS
t
WLH
T2
t
WLS
t
WLH
UNDEFINED DRIVING MODE
CK
Notes:
1. DRAM has the option to drive leveling feedback on a prime DQ or all DQs. If feedback is driven only on one DQ, the
remaining DQs must be driven low, as shown in above Figure, and maintained at this state through out the leveling
procedure.
2. MRS: Load MR1 to enter write leveling mode.
3. NOP: NOP or Deselect.
4. Diff_DQS is the differential data strobe (DQS, DQS#). Timing reference points are the zero crossings. DQS is shown with
solid line, DQS# is shown with dotted line.
5. CK, CK#: CK is shown with solid dark line, where as CK# is drawn with dotted line.
6. DQS, DQS# needs to fulfill minimum pulse width requirements t
DQSH
(min) and t
DQSL
(min) as defined for regular Writes; the
max pulse width is system dependent.
Figure 14
– Timing details of Write leveling sequence [DQS - DQS# is capturing CK - CK# low at
T1 and CK - CK# high at T2]