W972GG6JB-18-TR Datasheet, PDF (12/87 Pages) Winbond – 16M 8 BANKS 16 BIT DDR2 SDRAM

W972GG6JB
8.2.2.2 DLL Enable/Disable
The DLL must be enabled for normal operation. DLL enable is required during power-up initialization,
and upon returning to normal operation after having the DLL disabled. The DLL is automatically
disabled when entering Self Refresh operation and is automatically re-enabled and reset upon exit of
Self Refresh operation. Any time the DLL is enabled (and subsequently reset), 200 clock cycles must
occur before a Read command can be issued to allow time for the internal clock to be synchronized
with the external clock. Failing to wait for synchronization to occur may result in a violation of the tAC
or tDQSCK parameters.
BA2 BA1 BA0 A13 A12 A11 A10 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0
Address Field
0
0
1
0 Qoff 0*¹ DQS OCD program
Rtt AdditiveWLRatencByT Rtt D.I.C DLL Extended Mode Register (1)
BA1 BA0
0
0
0
1
1
0
1
1
MRS mode
MRS
EMR (1)
EMR (2)
EMR (3)
A6 A2 Rtt (nominal)
0
0 ODT disabled
0
1
75 ohm
1
0
150 ohm
1
1
50 ohm*²
A0 DLL Enable
0
Enable
1
Disable
Driver impedance adjustment
A9 A8 A7 OCD Calibration Program
0
0
0 OCD calibration mode exit; matain setting
0
0
1 Drive (1)
0
1
0 Drive (0)
1
0
0 Adjust mode*³
1
1
1 OCD Calibration default*⁴
A12
Qoff (Optional)*⁵
0 Output buffer enabled
1 Output buffer disabled
A10
DQS
0
Enable
1
Disable
A10
(DQS Enable)
0 (Enable)
1 (Disable)
Strobe Function Matrix
DQS
DQS
DQS
DQS
DQS
Hi-z
Additive Latency
A5 A4 A3
Latency
0
0
0
0
0
0
1
1
0
1
0
2
0
1
1
3
1
0
0
4
1
0
1
5
1
1
0
6
1
1
1 Reserved
Output Driver Impedance Control
A1
Output driver
impedance control
Driver
size
0
Normal
100%
1
Reduced
60%
Notes:
1. A11 default is “0” RDQS disabled.
2. Optional for DDR2-667, mandatory for DDR2-800 and DDR2-1066.
3. When Adjust mode is issued, AL from previously set value must be applied.
4. After setting to default, OCD calibration mode needs to be exited by setting A9-A7 to 000. Refer to the section 8.2.3 for
detailed information.
5. Output disabled - DQs, LDQS, LDQS , UDQS, UDQS . This feature is used in conjunction with DIMM IDD measurements
when IDDQ is not desired to be included.
Figure 3 – EMR (1)
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Publication Release Date: Jul. 28, 2014
Revision: A03