W632GU6NB
Publication Release Date: Aug. 20, 2018
Revision: A01
- 148 -
17. When the device is operated with input clock jitter, this parameter needs to be derated by the actual
t
ERR
(mper),act of the input clock, where 2
≤ m ≤ 12. (Output deratings are relative to the actual SDRAM
input clock.)
For example, if the measured jitter into a DDR3L-1333 SDRAM has t
ERR
(mper),act,min = - 138 pS and
t
ERR
(mper),act,max = + 155 pS, then
t
DQSCK,
min(derated) = t
DQSCK
,min - t
ERR
(mper),act,max = - 255 pS - 155 pS = - 410 pS and
t
DQSCK
,max(derated) = t
DQSCK
,max - t
ERR
(mper),act,min = 255 pS + 138 pS = + 393 pS.
Similarly, t
LZ(DQ)
for DDR3L-1333 derates to t
LZ(DQ)
,min(derated) = - 500 pS - 155 pS = - 655 pS and
t
LZ(DQ
),max(derated) = 250 pS + 138 pS = + 388 pS. (Caution on the min/max usage!)
Note that t
ERR
(mper),act,min is the minimum measured value of t
ERR
(nper) where 2
≤ n ≤ 12, and
t
ERR
(mper),act,max is the maximum measured value of t
ERR
(nper) where 2
≤ n ≤ 12.
18. When the device is operated with input clock jitter, this parameter needs to be derated by the actual
t
JIT
(per),act of the input clock. (Output deratings are relative to the SDRAM input clock.)
For example, if the measured jitter into a DDR3L-1333 SDRAM has t
CK
(avg),act = 1500 pS,
t
JIT
(per),act,min = - 58 pS and t
JIT
(per),act,max = + 74 pS, then
t
RPRE
,min(derated) = t
RPRE
,min + t
JIT
(per),act,min = 0.9 x t
CK
(avg),act + t
JIT
(per),act,min = 0.9 x 1500
pS - 58 pS = + 1292 pS.
Similarly, t
QH
,min(derated) = t
QH
,min + t
JIT
(per),act,min = 0.38 x t
CK
(avg),act + t
JIT
(per),act,min = 0.38 x
1500 pS - 58 pS = + 512 pS. (Caution on the min/max usage!).
19. WR in clock cycles as programmed in mode register MR0.
20. t
WR
(min) is defined in nS, for calculation of t
WRPDEN
it is necessary to round up t
WR
(min)/t
CK
(avg) to the
next integer value.
21. The maximum read preamble is bound by t
LZ(DQS
)
min on the left side and t
DQSCK
(max) on the right side.
See Figure 24 -
“READ Timing; Clock to Data Strobe relationship”
on page 46.
22. The maximum read postamble is bound by t
DQSCK
(min) plus t
QSH
(min) on the left side and t
HZ
(DQS)
max
on the right side. See Figure 24 -
“READ Timing; Clock to Data Strobe relationship”
on page 46.
23. Value is only valid for RON34.
24. Single ended signal parameter.
25. t
REFI
depends on T
OPER
.
26. Start of internal write transaction is defined as follows:
For BL8 (fixed by MRS and on- the-fly): Rising clock edge 4 clock cycles after WL.
For BC4 (on- the- fly): Rising clock edge 4 clock cycles after WL.
For BC4 (fixed by MRS): Rising clock edge 2 clock cycles after WL.
27. CKE is allowed to be registered low while operations such as row activation, precharge, auto-precharge
or refresh are in progress, but power down I
DD
spec will not be applied until finishing those operations.
28. Although CKE is allowed to be registered LOW after a REFRESH command once t
REFPDEN
(min) is
satisfied, there are cases where additional time such as t
XPDLL
(min) is also required. See section 8.17.3
“Power-Down clarifications - Case 2”
on page 76.
29. Defined between end of MPR read burst and MRS which reloads MPR or disables MPR function.
30. ODTH4 is measured from ODT first registered high (without a Write command) to ODT first registered
low, or from ODT registered high together with a Write command with burst length 4 to ODT registered
low.
31. ODTH8 is measured from ODT registered high together with a Write command with burst length 8 to
ODT registered low.
32. This parameter applies upon entry and during precharge power down mode with DLL frozen.