NTC Proprietary
Level: Property
DDR3(L)-2Gb SDRAM
NT5CB(C)256M8JQ/NT5CB(C)128M16JR
Timing detail of Write Leveling exit
T0
T1
T2
Ta0
Tb0
Tc0
Tc1
Tc2
Td0
Td1
Te0
Te1
CK
CK
CMD
NOP
NOP
NOP
NOP
NOP
NOP
NOP
MRS
MR1
NOP
tMRD
Valid
tMOD
Valid
NOP
Valid
Valid
BA
ODT
tAOFmin
tIS
tODTLoff
tWLO
RTT_DQS_DQS
RTT_Nom
tAOFmax
DQS_DQS
DQ
Result = 1
Undefined
Driving Mode
Time Break
Transitioning
Do not Care
Extended Temperature Usage
Nanya’s DDR3(L) SDRAM supports the optional extended temperature range of 0°C to +95°C, TC. Thus, the SRT and
ASR options must be used at a minimum. The extended temperature range DRAM must be refreshed externally at 2X
(double refresh) anytime the case temperature is above +85°C (in supporting temperature range). The external refreshing
requirement is accomplished by reducing the refresh period from 64ms to 32ms. However, self refresh mode requires
either ASR or SRT to support the extended temperature. Thus either ASR or SRT must be enabled when TC is above
+85°C or self refresh cannot be used until the case temperature is at or below +85°C.
Mode Register Description
Field
Bits
Description
Auto Self-Refresh (ASR)
When enabled, DDR3(L) SDRAM automatically provides Self-Refresh power management functions for all
supported operating temperature values. If not enabled, the SRT bit must be programmed to indicate TOPER
during subsequent Self-Refresh operation.
ASR
MR2(A6)
0 = Manual SR Reference (SRT)
1 = ASR enable
Self-Refresh Temperature (SRT) Range
If ASR = 0, the SRT bit must be programmed to indicate TOPER during subsequent Self-Refresh operation. If
ASR = 1, SRT bit must be set to 0.
SRT
MR2(A7)
0 = Normal operating temperature range
1 = Extended operating temperature range
Version 1.4
05/2019
42
Nanya Technology Cooperation ©
All Rights Reserved.
NANYA [ Nanya Technology Corporation. ]
