W632GU6NB
Publication Release Date: Aug. 20, 2018
Revision: A01
- 14 -
4. The DDR3L SDRAM keeps its on-die termination in high-impedance state as long as RESET# is
asserted. Further, the SDRAM keeps its on-die termination in high impedance state after RESET#
deassertion until CKE is registered HIGH. The ODT input signal may be in undefined state until t
IS
before CKE is registered HIGH. When CKE is registered HIGH, the ODT input signal may be
statically held at either LOW or HIGH. If Rtt_Nom is to be enabled in MR1, the ODT input signal
must be statically held LOW. In all cases, the ODT input signal remains static until the power up
initialization sequence is finished, including the expiration of t
DLLK
and t
ZQ
init.
5. After CKE is being registered high, wait minimum of Reset CKE Exit time, t
XPR
, before issuing the
first MRS command to load mode register. (t
XPR
=max (t
XS
; 5 * t
CK
)
6. Issue MRS Command to load MR2 with all application settings. (To issue MRS command for MR2,
provide “Low” to BA0 and BA2, “High” to BA1.)
7. Issue MRS Command to load MR3 with all application settings. (To issue MRS command for MR3,
provide “Low” to BA2, “High” to BA0 and BA1.)
8. Issue MRS Command to load MR1 with all application settings and DLL enabled. (To issue
“DLL
Enable
” command, provide “Low” to A0, “High” to BA0 and “Low” to BA1-BA2).
9. Issue MRS Command to load MR0 with all application settings and
“DLL reset”. (To issue DLL
reset command, provide
“High” to A8 and “Low” to BA0-2).
10. Issue ZQCL command to starting ZQ calibration.
11. Wait for both t
DLLK
and t
ZQ
init completed.
12. The DDR3L SDRAM is now ready for normal operation.
TIME BREAK
DON'T CARE
Ta
Tb
Tc
Td
Te
Tf
Tg
Th
Ti
Tj
Tk
CK, CK#
VDD, VDDQ
RESET#
Command
BA
ODT
RTT
t
CKSRX
T = 200 µs
T = 500 µs
t
DLLK
VALID
VALID
VALID
VALID
Static LOW in case Rtt_Nom is enabled at time Tg. Otherwise static HIGH or LOW
*1
ZQCL
MRS
*1
MRS
MRS
MRS
MR2
MR3
MR1
MR0
t
IS
t
IS
t
IS
t
IS
t
XPR
t
MRD
t
MRD
t
MRD
t
MOD
t
ZQ
init
Tmin
CKE
10 ns
Note:
1.
From time point “Td” until “Tk” NOP or DES commands must be applied between MRS and ZQCL commands.
Figure 1
– Reset and Initialization Sequence at Power-on Ramping