EM47CM1688SBB
Revision History
Revision 0.1 (Jun. 2012)
-First release.
Jun. 2012
1/38
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EM47CM1688SBB
1Gb (8M×8Bank×16) Double DATA RATE 3 SDRAM
Features
Description
• JEDEC Standard VDD/VDDQ = 1.5V±0.075V.
• All inputs and outputs are compatible with SSTL_15
interface.
• Fully differential clock inputs (CK, /CK) operation.
• Eight Banks
• Posted CAS by programmable additive latency: 0,
CL-1 & CL-2
• Bust length: 4 with Burst Chop (BC) and 8.
• CAS Write Latency (CWL): 5,6,7,8
• Programmable CAS Latency (CL): 6, 7, 8, 9, 10, 11
• Write Latency (WL) =Read Latency (RL) -1.
• Bi-directional Differential Data Strobe (DQS).
• Data inputs on DQS centers when write.
• Data outputs on DQS, /DQS edges when read.
• On chip DLL align DQ, DQS and /DQS transition
with CK transition.
• DM mask write data-in at the both rising and falling
edges of the data strobe.
• Sequential & Interleaved Burst type available both
for 8 & 4 with BC.
• Multi Purpose Register (MPR) for pre-defined
pattern read out
• On Die Termination (ODT) options: Synchronous
ODT, Dynamic ODT, and Asynchronous ODT
• Auto Refresh and Self Refresh
• 8,192 Refresh Cycles / 64ms
• Refresh Interval: 7.8us Tcase between 0°C ~ 85°C
• Refresh Interval: 3.9us Tcase between 85°C ~ 95°C
• RoHS Compliance
• Driver Strength:RZQ/7, RZQ/6 (RZQ=240Ω)
• High Temperature Self-Refresh rate enable
• ZQ calibration for DQ drive and ODT
• RESET pin for initialization and reset function
The EM47CM1688SBB is a high speed Double Date
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Rate 3 (DDR3) Synchronous DRAM fabricated with
ultra high performance CMOS process containing 1G
bits which organized as 8Mbits x 8 banks by 16 bits.
This synchronous device achieves high speed
double-data-rate transfer rates of up to 1600
Mb/sec/pin (DDR3-1600) for general applications.
The chip is designed to comply with the following key
DDR3 SDRAM features: (1) posted CAS with
additive latency, (2) write latency = read latency -1,
(3) On Die Termination (4) programmable driver
strength data,(5) seamless BL4 access. All of the
control and address inputs are synchronized with a
pair of externally supplied differential clocks. Inputs
are latched at the cross point of differential clocks
(CK rising and /CK falling). All I/Os are synchronized
with a pair of bidirectional differential data strobes
(DQS and /DQS) in a source synchronous fashion.
The address bus is used to convey row, column and
bank address information in a /RAS and /CAS
multiplexing style. The 1Gb DDR3 devices operates
with a single power supply: 1.5V ± 0.075V VDD and
VDDQ. Available package: FBGA-96Ball (with 0.8mm
- 0.8mm ball pitch)
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EM47CM1688SBB
Ordering Information
Organization Max. Freq
Part No
Package
Grade
EM47CM1688SBA-150
64M X 16
DDR3-1333H (9-9-9)
FBGA-96B
Commercial
EM47CM1688SBA-125
64M X 16
DDR3-1600K (11-11-11)
FBGA-96B
Commercial
Note: Speed ( tCK *) is in order of CL-tRCD-tRP
Parts Naming Rule
* EOREX reserves the right to change products or specification without notice.
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EM47CM1688SBB
Pin Assignment: Top View
1
2
3
7
8
VDDQ
DQU5
DQU7
VSSQ
VDD
VSS
VDDQ
DQU3
VSSQ
9
A
DQU4
VDDQ
VSS
B
/DQSU
DQU6
VSSQ
DQU1
C
DQSU
DQU2
VDDQ
VDDQ
DMU
D
DQU0
VSSQ
VDD
VSS
VSSQ
DQL0
E
DML
VSSQ
VDDQ
VDDQ
DQL2
DQSL
F
DQL1
DQL3
VSSQ
VSSQ
DQL6
/DQSL
G
VDD
VSS
VSSQ
VREFDQ
VDDQ
DQL4
H
DQL7
DQL5
VDDQ
NC
VSS
RAS
J
CK
VSS
NC
ODT
VDD
CAS
K
CK
VDD
CKE
NC
CS
WE
L
A10/AP
ZQ
NC
VSS
BA0
BA2
M
NC
VREFCA
VSS
VDD
A3
A0
N
A12/ BC
BA1
VDD
VSS
A5
A2
P
A1
A4
VSS
VDD
A7
A9
R
A11
A6
VDD
VSS
RESET
NC
T
NC
A8
VSS
96 Ball FBGA
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EM47CM1688SBB
Pin Description (Simplified)
Pin
Name
Function
(System Clock)
J7,K7
CK, CK
CK and CK are differential clock inputs. All address and control
input signals are sampled on the crossing of the positive edge of
CK and negative edge of CK . Output (read) data is referenced to
the crossings of CK and CK (both directions of crossing).
(Chip Select)
L2
CS
All commands are masked when CS is registered HIGH.
CS provides for external Rank selection on systems with
multiple Ranks. CS is considered part of the command code.
K9
CKE
(Clock Enable)
CKE high activates and CKE low deactivates internal clock
signals and device input buffers and output drivers. Taking CKE
low provides precharge power-down and self- refresh operation
(all banks idle), or active power-down (row active in any bank).
CKE is asynchronous for self refresh exit. After VREFCA has
become stable during the power on and initialization sequence, it
must be maintained during all operations (including self-refresh).
CKE must be maintained high throughout read and write
accesses. Input buffers, excluding CK, CK , ODT and CKE are
disabled during power-down. Input buffers, excluding CKE, are
disabled during self -refresh.
(Address)
N3,P7,P3,N2,
P8,P2,R8,R2,
T8,R3,L7,R7,
A0~A9,A10/AP,
A11,A12( BC ),
N7
Provided the row address (RA0 – RA12) for active commands
and the column address (CA0-CA9) and auto precharge bit for
read/write commands to select one location out of the memory
array in the respective bank. A10 is sampled during a precharge
command to determine whether the precharge applies to one
bank (A10 LOW) or all banks (A10 HIGH). The address inputs
also provide the op-code during Mode Register Set commands.
A12 is sampled during read and write commands to determine if
burst chop (on-the-fly) will be performed. (HIGH: no burst chop,
LOW: burst chopped). See command truth table for details.
(Bank Address)
M2,N8,M3
K1
BA0, BA1,BA2
ODT
BA0 – BA2 define to which bank an active, read, write or
precharge command is being applied. Bank address also
determines if the mode register is to be accessed during a MRS
cycle.
(On Die Termination)
ODT (registered HIGH) enables termination resistance internal to
the DDR3 SDRAM. When enabled, ODT is applied to each DQ,
DQS, DQS , DMU and DML signal. The ODT pin will be ignored if
the Mode Register MR1 is programmed to disable ODT.
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EM47CM1688SBB
Pin Description (Continued)
DQSU,
C7,B7,F3,G3
DQSU ,
DQSL,
DQSL
J3, K3, L3
RAS ,
CAS , WE
(Data Strobe)
Output with read data, input with write data. Edge-aligned with read data,
centered in write data. DQSL corresponds to the data on DQL0-DQL7;
DQSU corresponds to the data on DQU0-DQU7. The data strobes DQSL,
and DQSU are paired with differential signals DQSU and DQSL
respectively, to provide differential pair signaling to the system during
reads and writes. DDR3 SDRAM supports differential data strobe only and
does not support single-ended.
(Command Inputs)
RAS , CAS & WE (along with CS ) define the command being entered.
(Input Data Mask)
D3,E7
D7,C3,C8,C2,A7,
A2,B8,A3
E3,F7,F2,F8,H3,
H8,G2,H7
B2,D9,G7,K2,K9,N
1,N9,R1,R9/A9,B3,
E1,G8,J2,J8,M1,M
9,P1,P9,T1,T9
A1,A8,C1,C9,D2,E
9,F1,H2,H9 /B1,
B9,D1,D8,E2,E8,
F9,G1,G9
L8
DMU,DML
DQU0~7
DQL0~7
VDD/VSS
VDDQ,
/VSSQ
ZQ
DMU & DML are input mask signal for write data. Input data is masked
when DMU or DML are sampled HIGH coincident with that input data
during a write access. DMU & DML is sampled on both edges of DQSU &
DQML respectively.
(Data Input/Output)
Data inputs and outputs are on the same pin.
(Data Input/Output)
Data inputs and outputs are on the same pin.
(Power Supply/Ground)
VDD and VSS are power supply for internal circuits.
(DQ Power Supply/DQ Ground)
VDDQ and VSSQ are power supply for the output buffers.
(ZQ Calibration)
Reference pin for ZQ calibration
(Active Low Asynchronous Reset)
Reset is active when RESET is LOW, and inactive when RESET is
T2
RESET
H1
VREFDQ
M8
VREFCA
J1,J9,L1,L9,
M7,T3, T7
NC
HIGH. RESET must be HIGH during normal operation. RESET is a
CMOS rail to rail signal with DC high and low at 80% and 20% of VDD, i.e.
1.20V for DC high and 0.30V for DC low.
(Reference Voltage)
Reference voltage for DQ
(Reference Voltage)
Reference voltage for CA
(No Connection)
No internal electrical connection is present.
Note: Input pins only BA0-BA2, A0-A12, RAS , CAS , WE , CS , CKE, ODT and RESET do not supply
termination.
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EM47CM1688SBB
Absolute Maximum Rating
Symbol
Item
Rating
Units
VIN, VOUT
Input, Output Voltage
-0.4 ~ +1.975
V
VDD
Power Supply Voltage
-0.4 ~ +1.975
V
VDDQ
Power Supply Voltage
-0.4 ~ +1.975
V
TOP
Operating Temperature Range
TSTG
Storage Temperature Range
-55 ~ +100
°C
VREFCA
Reference Voltage for Control
-0.4 ~ 0.6*VDD
V
VREFDQ
Reference Voltage for DQ
-0.4 ~ 0.6*VDDQ
V
Commercial
°C
0 ~ +70
Note: Caution Exposing the device to stress above those listed in Absolute Maximum Ratings
could cause permanent damage. The device is not meant to be operated under conditions
outside the limits described in the operational section of this specification.
Recommended DC Operating Conditions
Symbol
Parameter
Min.
Typ.
Max.
Units
VDD
Power Supply Voltage
1.425
1.5
1.575
V
VDDQ
Power Supply for I/O Voltage
1.425
1.5
1.575
V
Single-Ended AC and DC Input Levels for Command and Address
Symbol
Parameter
Min.
Max.
Units
VIHCA (DC100)
DC input logic high
VREF+0.100
VDD
V
VILCA (DC100)
DC input logic low
VSS
VREF-0.100
V
VIHCA (AC175)
AC input logic high
VREF+0.175
-
V
VILCA (AC175)
AC input logic low
-
VREF-0.175
V
VIHCA (AC150)
AC input logic high
VREF+0.150
-
V
VILCA (AC150)
AC input logic low
-
VREF-0.150
V
0.49*VDD
0.51*VDD
V
Max.
Units
VREFCA (DC)
Reference voltage for ADD, CMD
Single-Ended AC and DC Input Levels for DQ and DM
Symbol
Parameter
Min.
VIHDQ (DC100)
DC input logic high
VREF+0.100
VDD
V
VILDQ (DC100)
DC input logic low
VSS
VREF-0.100
V
VIHDQ (AC175)
AC input logic high
VREF+0.150
-
V
VILDQ (AC175)
AC input logic low
-
VREF-0.150
V
VIHDQ (AC150)
AC input logic high
VREF+0.150
-
V
VILDQ (AC150)
AC input logic low
-
VREF-0.150
V
VREFDQ (DC)
Reference voltage for DQ, DM
0.49*VDD
0.51*VDD
V
Note1. For input pins except /RESET: VREF= VREFCA (DC) or VREF= VREFDQ (DC).
Note2. The AC peak noise on VREF may not allow VREF to deviate from VREFCA (DC) or VREF= VREFDQ (DC)
by more than ±1% VDD (for reference: approx. ±15mV.
Note3. For reference voltage = VDD/2 ±15mV.
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EM47CM1688SBB
Pin Capacitance
Symbol
Parameters
Pins
Min.
Max.
Unit
Notes
CCK
Input pin capacitance, CK, /CK
CK, /CK
0.8
1.4
pF
1,3
CDCK
Delta input pin capacitance,
CK, /CK
0
0.15
pF
1,2
CIN_CTRL
Input pin capacitance, control
pins
0.75
1.3
pF
1
CDIN_CTRL
Delta input pin capacitance,
control pins
-0.4
0.2
pF
1,4
CIN_ADD_CMD
Input pin capacitance, address
and command pins
0.75
1.3
pF
1
CDIN_ADD_CMD
Delta input pin capacitance,
address and command pins
-0.4
0.4
pF
1,5
CIO
Input/output pins capacitance
CDIO
Delta input/output pins
capacitance
CDDQS
CZQ
/CS,CKE,ODT
/RAS,/CAS,/WE,
Address
DQ,DQSU,/DQSU
DQSL,/DQSL,
DMU, DML
1.5
2.5
pF
1,6
-0.5
0.3
pF
1,7,8
Delta input/output pins
capacitance
DQS, /DQS
0
0.15
pF
1,10
Input/output pin capacitance,
ZQ
ZQ
-
3
pF
1,9
Notes1. VDD, VDDQ, VSS, VSSQ applied and all other pins (except the pin under test) floating. VDD = VDDQ
=1.5V, VBIAS=VDD/2.
Notes2. Absolute value of CCK(CK-pin) - CCK(/CK-pin).
Notes3. CCK (min.) will be equal to CIN (min.)
Notes4. CDIN_CTRL = CIN_CTRL - 0.5*(CCK(CK-pin) + CCK(/CK-pin))
Notes5. CDIN_ADD_CMD = CIN_ADD_CMD - 0.5*(CCK(CK-pin) + CCK(/CK-pin))
Notes6. Although the DMU and DML pins have different functions, the loading matches DQ and DQS.
Notes7. DQ should be in high impedance state.
Notes8. CDIO = CIO (DQ, DM) - 0.5*(CIO(DQS-pin) + CIO(/DQS-pin)).
Notes9. Maximum external load capacitance on ZQ pin is 5pF.
Notes10. Absolute value of CIO(DQS) - CIO(/DQS).
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EM47CM1688SBB
AC and DC Logic Input Levels for Differential Signals
Differential signals definition
Differential AC and DC Input Levels
Parameter
Min.
Max.
Units
Note
VIHdiff
Differential input high
+0.2
See Note3
V
1
VILdiff
Differential input low
See Note3
-0.2
V
1
Symbol
VIHdiff (AC)
AC Differential input high
2x(VIH(AC)-VREF)
See Note3
V
2
VILdiff (AC)
AC Differential input low
See Note3
2x(VIL(AC)-VREF)
V
2
Note1. It is used to define a differential signal slew-rate.
Note2. For CK - /CK use VIH/VIL(AC) of address/command and VREFCA; for strobes (DQS, DQS) use VIH/VIL(AC) of
DQs and VREFDQ; if a reduced ac-high or ac-low level is used for a signal group, then the reduced level applies
also here.
Note3. These values are not defined, however they single-ended signals CK, /CK, DQS, /DQS need to be
within the respective limits (VIH(DC) max, VIL(DC)min) for single-ended signals.
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EM47CM1688SBB
Differential swing requirements for clock (CK - /CK) and strobe (DQS - /DQS)
- Allowed time before ringback (tDVAC) for CK - /CK and DQS - /DQS
Slew Rate [V/ns]
tDVAC [ps] @ |VIH/Ldiff(ac)| = 350mV
tDVAC [ps] @ |VIH/Ldiff(ac)| = 300mV
-
Min
Max
Min
Max
>4.0
75
-
175
-
4.0
57
-
170
-
3.0
50
-
167
-
2.0
38
-
163
-
1.8
34
-
162
-
1.6
29
-
161
-
1.4
22
-
159
-
1.2
13
-
155
-
1.0
0
-
150
-
<1.0
0
-
150
-
Single-ended requirements for differential signals
Each individual component of a differential signal (CK, DQS, /CK, /DQS) has also to comply with certain
requirements for single-ended signals.
CK and /CK have to approximately reach VSEHmin / VSELmax (approximately equal to the ac-levels
(VIH(AC) / VIL(AC) ) for Address/Command signals) in every half-cycle.
DQS, /DQS have to reach VSEHmin / VSELmax [approximately the ac-levels (VIH(AC) / VIL(AC) ) for DQ
signals] in every half-cycle preceding and following a valid transition.
Note that the applicable AC-levels for Address/Command and DQ’s might be different per speed-bin etc. E.g., if
VIHCA(AC150)/VILCA(AC150) is used for Address/Command signals, then these AC-levels apply also for the
single-ended components of differential CK and /CK.
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EM47CM1688SBB
Note that while Address/command and DQ signal requirements are with respect to VREF, the single-ended
components of differential signals have a requirement with respect to VDD/2; this is nominally the same.
The transition of single-ended signals through the AC-levels is used to measure setup time. For singleended
components of differential signals the requirement to reach VSEL max, VSEH min has no bearing on timing, but
adds a restriction on the common mode characteristics of these signals.
Single-ended levels for CK, DQS, /CK, /DQS
Symbol
VSEH
VSEL
Min.
Max.
Units
Note
Single-ended high-level for strobes
(VDD/2)+0.175
See Note3
V
1,2
Single-ended high-level for CK, /CK
(VDD/2)+0.175
See Note3
V
1,2
Single-ended low-level for strobes
See Note3
(VDD/2)-0.175
V
1,2
Single-ended low-level for CK, /CK
See Note3
(VDD/2)-0.175
V
1,2
Parameter
Note1. For CK, /CK use VIH/VIL(AC) of address/command; for strobes (DQS, DQS) use VIH/VIL(AC) of DQs.
Note2. VIH(AC)/VIL(AC) for DQs is based on VREFDQ; VIH(AC)/VIL(AC) for address/command is based on
VREFCA; if a reduced AC-high or AC-low level is used for a signal group, then the reduced level
applies also here.
Note3. These values are not defined, however the single-ended components of differential signals CK, /CK,
DQS, /DQS need to be within the respective limits (VIH(DC) max, VIL(DC) min) for single-ended signals
as well as the limitations for overshoot and undershoot.
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EM47CM1688SBB
AC and DC Output Measurement Levels
Symbol
Parameter
VOH(DC)
Note
Specification
Units
DC output high measurement level (for IV curve linearity)
0.8*VDDQ
V
VOM(DC)
DC output middle measurement level (for IV curve linearity)
0.5*VDDQ
V
VOL(DC)
DC output low measurement level (for IV curve linearity)
0.2*VDDQ
V
VOH(AC)
AC output high measurement level (for output slew rate)
VTT+0.1*VDDQ
V
1
VOL(AC)
AC output low measurement level (for output slew rate)
VTT-0.1*VDDQ
V
1
VOHdiff(DC)
AC differential output high measurement level (for output
slew rate)
0.2*VDDQ
V
VOLdiff(DC)
AC differential output low measurement level (for output
slew rate)
-0.2*VDDQ
V
2
2
Notes1. The swing of ±0.1 × VDDQ is based on approximately 50% of the static single-ended output high or
low swing with a driver impedance of 34Ω and an effective test load of 25Ω to VTT = VDDQ/2 at each of the
differential outputs.
Notes2. The swing of ±0.2 × VDDQ is based on approximately 50% of the static single-ended output high or
low swing with a driver impedance of 34Ω and an effective test load of 25Ω to VTT = VDDQ/2 at each of the
differential outputs.
DQS Output Crossing Voltage - VOX (DDR3-1600 or Higher Speed Bin)
DQS, /DQS differential slew rate
Symbol
Parameters
5V/ns 6V/ns 7V/ns 8V/ns 9V/ns
Deviation of DQS,
VOX (AC) max. /DQS output
+100 +120 +140 +160 +180
cross point
VOX (AC) min. voltage from
-100
-120
-140
-160
-180
0.5*VDDQ
DQS Output Crossing Voltage - VOX (DDR3-1333 or Lower Speed Bin)
DQS, /DQS differential slew rate
Symbol
Parameters
5V/ns 6V/ns 7V/ns 8V/ns 9V/ns
Deviation of DQS,
VOX (AC) max. /DQS output
+125 +150 +175 +200 +225
cross point
-125
-150
-175
-200
-225
VOX (AC) min. voltage from
0.5*VDDQ
Unit
10V/ns
11V/ns
12V/ns
+200
+200
+200
mV
-200
-200
-200
mV
10V/ns
11V/ns
12V/ns
+225
+225
+225
mV
-225
-225
-225
mV
Unit
Notes1. Measured using an effective test load of 25Ω to 0.5* VDDQ at each of the differential outputs.
Notes2. For a differential slew rate in between the listed values, the VOX value may be obtained by linear
interpolation.
Notes3. The DQS, /DQS pins under test are not required to be able to drive each of the slew rates listed in the
table; the pins under test will provide one VOX value when tested with specified test condition. The DQS and
/DQS differential slew rate when measuring VOX determines which VOX limits to use.
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EM47CM1688SBB
Recommended DC Operating Conditions
(VDD,VDDQ=1.5V±0.075V)
Symbol
-125
Parameter & Test Conditions
-150
Max
Units
Operating One Bank Active-Read-Precharge Current:
IDD1
CKE: High; External clock: On; tCK, nRC, nRAS, nRCD, CL: see
timing used table; BL: 81; AL: 0; /CS: High between ACT, RD and
PRE; Command, Address, Data IO: partially toggling; DM:stable at 0;
Bank Activity: Cycling with one bank active at a time; Output Buffer
and RTT: Enabled in Mode Registers; ODT Signal: stable at 0
120
115
mA
30
25
mA
40
35
mA
35
30
mA
220
190
mA
230
200
mA
170
160
mA
Precharge Power-Down Current Fast Exit:
IDD2P1
CKE: Low; External clock: On; tCK, CL: see timing used table; BL: 8;
AL: 0; /CS: stable at 1; Command, Address: stable at 0; Data IO:
FLOATING; DM: stable at 0; Bank Activity: all banks closed; Output
Buffer and RTT: Enabled in Mode Registers; ODT Signal: stable at 0;
Pre-charge Power Down Mode: Fast Exit
Precharge Standby Current:
IDD2N
CKE: High; External clock: On; tCK, CL: see timing used table; BL: 8;
AL: 0; /CS: stable at 1; Command, Address: partially toggling; Data
IO: FLOATING; DM:stable at 0; Bank Activity: all banks closed;
Output Buffer and RTT: Enabled in Mode Registers; ODT Signal:
stable at 0
Active Power-Down Current:
IDD3P
CKE: Low; External clock: On; tCK, CL: see timing used table; BL: 8;
AL: 0; /CS: stable at 1; Command, Address: stable at 0; Data IO:
FLOATING; DM: stable at 0; Bank Activity: all banks open; Output
Buffer and RTT: Enabled in Mode Registers; ODT Signal: stable at 0
Operating Burst Write Current:
IDD4W
CKE: High; External clock: On; tCK, CL: see timing used table; BL: 8;
AL: 0; /CS: High between WR; Command, Address: partially toggling;
Data IO: seamless write data burst with different data between one
burst and the next one; DM: stable at 0; Bank Activity: all banks open,
WR commands cycling through banks: 0,0,1,1,2,2,...; Output Buffer
and RTT: Enabled in Mode Registers; ODT Signal: stable at HIGH
Operating Burst Read Current:
IDD4R
CKE: High; External clock: On; tCK, CL: see timing used table; BL: 8;
AL: 0; /CS: High between RD; Command, Address: par-tially toggling;
Data IO: seamless read data burst with different data between one
burst and the next one; DM: stable at 0; Bank Activity: all banks open,
RD commands cycling through banks: 0,0,1,1,2,2,...; Output Buffer
and RTT: Enabled in Mode Registers; ODT Signal: stable at 0
Burst Refresh Current:
IDD5B
Jun. 2012
CKE: High; External clock: On; tCK, CL, nRFC: see timing used
table; BL: 8; AL: 0; /CS: High between REF; Command, Address:
partially toggling; Data IO: FLOATING; DM: stable at 0; Bank Activity:
REF command every nRFC; Output Buffer and RTT: Enabled in
Mode Registers; ODT Signal: stable at 0
13/38
www.eorex.com
EM47CM1688SBB
-125
-150
Symbol
Parameter & Test Conditions
IDD6
Self Refresh Current: Normal Temperature Range; TCASE: 085°C; Auto Self-Refresh (ASR): Disabled; Self-Refresh
Temperature Range (SRT): Normal; CKE: Low; External clock: Off;
CK and /CK: LOW; CL: see timing used table; BL: 8; AL: 0; CS,
Command, Address, Data IO: FLOATING; DM: stable at 0; Bank
Activity: Self-Refresh operation; Output Buffer and RTT: Enabled in
Mode Registers; ODT Signal: FLOATING
8
8
mA
IDD7
Operating Bank Interleave Read Current; CKE: High; External
clock: On; tCK, nRC, nRAS, nRCD, nRRD, nFAW, CL: see timing
used table; BL: 8; AL: CL-1; CS: High between ACT and RDA;
Command, Address: partially toggling; Data IO: read data bursts
with different data between one burst and the next one; DM: stable
at 0; Bank Activity: two times interleaved cycling through banks (0,
1, ...7) with different addressing; Output Buffer and RTT: Enabled in
Mode Registers; ODT Signal: stable at 0
300
270
mA
Max
Units
Note 1: Burst Length: BL8 fixed by MRS: set MR0 A[1,0]=00B
Note 2: Output Buffer Enable: set MR1 A[12] = 0B; set MR1 A[5,1] = 01B; RTT_Nom enable: set MR1 A[9,6,2]
= 011B; RTT_Wr enable: set MR2 A[10,9] = 10B
Note 3: Precharge Power Down Mode: set MR0 A12=0B for Slow Exit or MR0 A12=1B for Fast Exit
Note 4: Auto Self-Refresh (ASR): set MR2 A6 = 0B to disable or 1B to enable feature
Note 5: Self-Refresh Temperature Range (SRT): set MR2 A7=0B for normal or 1B for extended temperature
range
Note 6: Refer to DRAM supplier data sheet and/or DIMM SPD to determine if optional features or requirements
are supported by DDR3 SDRAM
Note 7: Read Burst type: Nibble Sequential, set MR0 A[3]=0B
Jun. 2012
14/38
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EM47CM1688SBB
Block Diagram
DM
/RESET
Auto/ Self
Refresh Counter
ZQ
ODT
DQM
Control
A0
CLK, /CLK
A1
A2
A6
A7
A8
A9
Row Decoder
A5
Address Register
A4
DQS
Generator
Row Add. Buffer
A3
DLL
Memory
Array
Driver
S/ A & I/ O Gating
A10
Write
FIFO
CLK, /CLK
A11
Col. Decoder
A12
A13
Receiver
Col. Add. Buffer
BA0
BA1
BA2
Data In
Mode Register Set
Data Out
Col Add. Counter
Burst Counter
DIO
Timing Register
DQ[7:0]
/CLK
Jun. 2012
CLK
CKE
/CS
/ RAS
15/38
/ CAS
/ WE
DM/TDQS /TDQS DQS,/DQS
www.eorex.com
EM47CM1688SBB
AC Operating Test Characteristics
DDR3-1333 & DDR3-1600 Speed Bins
(VDD, VDDQ=1.5V±0.075V)
Symbol
Speed Bin
-125
(DDR3-1600)
-150
(DDR3-1333)
CL-nRCD-nRP
11-11-11
9-9-9
Parameter
Min.
Max.
Min.
Max.
Units
Notes
tAA
Internal read command to first data
13.75
-
13.5
-
ns
8
tRCD
Active to read or write delay
13.75
-
13.5
-
ns
8
tRP
Precharge command period
13.75
-
13.5
-
ns
8
tRC
Active to active/auto refresh command
48.75
-
49.5
-
ns
8
tRAS
Active to precharge command period
35
9*tREFI
36
9*tREFI
ns
7
tCK (AVG)
Average Clock Cycle, CL=6, CWL=5
2.5
3.3
2.5
3.3
ns
1,2,3,5
.6
tCK (AVG)
Average Clock Cycle, CL=7, CWL=6
1.875
2.5
1.875
2.5
ns
1,2,3,4
,5,6
tCK (AVG)
Average Clock Cycle, CL=8, CWL=6
1.875
2.5
1.875
2.5
ns
1,2,3,5
,6
tCK (AVG)
Average Clock Cycle, CL=9, CWL=7
1.5
1.875
1.5
1.875
ns
1,2,3,4
,6
tCK (AVG)
Average Clock Cycle, CL=10, CWL=7
1.5
1.875
1.5
1.875
ns
1,2,3,6
tCK (AVG)
Average Clock Cycle, CL=11, CWL=8
1.25
1.5
-
-
ns
1,2,3
-
Support CL Settings
6,7,8,9,10,11
6,7,8,9,10
nCK
-
Support CWL Settings
5,6,7,8
5,6,7
nCK
Notes1. The CL setting and CWL setting result in tCK (avg) (min.) and tCK (avg) (max.) requirements. When
making a selection of tCK (avg), both need to be fulfilled: Requirements from CL setting as well as
requirements from CWL setting.
Notes2. tCK (avg) (min.) limits: Since /CAS latency is not purely analog - data and strobe output are
synchronized by the DLL - all possible intermediate frequencies may not be guaranteed. An application
should use the next smaller JEDEC standard tCK (avg) value (2.5, 1.875, 1.5, or 1.25ns) when
calculating CL (nCK) = tAA (ns) / tCK (avg)(ns), rounding up to the next ‘Supported CL’.
Notes3. tCK (avg) (max.) limits: Calculate tCK (avg) + tAA (max.)/CL selected and round the resulting tCK (avg)
down to the next valid speed bin (i.e. 3.3ns or 2.5ns or 1.875ns or 1.25ns). This result is tCK (avg)
(max.) corresponding to CL selected.
Notes4. ‘Reserved’ settings are not allowed. User must program a different value.
Notes5. Any DDR3-1333 speed bin also supports functional operation at lower frequencies as shown in the
table DDR3-1333 Speed Bins which is not subject to production tests but verified by
design/characterization.
Notes6. Any DDR3-1600 speed bin also supports functional operation at lower frequencies as shown in the
table DDR3-1600 Speed Bins which is not subject to production tests but verified by
design/characterization.
Notes7. tREFI depends on operating case temperature (TC).
Notes8. For devices supporting optional down binning to CL = 7 and CL = 9, tAA/tRCD/tRP(min.) must be
13.125 ns or lower. SPD settings must be programmed to match.
Jun. 2012
16/38
www.eorex.com
EM47CM1688SBB
AC Operating Test Characteristics
(VDD, VDDQ=1.5V±0.075V)
Symbol
Speed Bin
-125
(DDR3-1600)
-150
(DDR3-1333)
CL-nRCD-nRP
11-11-11
9-9-9
Parameter
Units
Notes
6
Min.
Max.
Min.
Max.
8
-
8
-
ns
Average CK high/low level width
0.47
0.53
0.47
0.53
ns
tRRD
Active bank A to active bank B
command period
7.5
-
7.5
-
ns
4
-
4
-
nCK
tFAW
Four Activate Window
40
-
45
-
ns
tIH(base)
DC100
Address and Control input hold time
(VIH/VIL(DC100) levels)
120
-
140
-
ps
16
tIS(base)
AC175
Address and Control input setup time
(VIH/VIL(AC175) levels)
45
-
65
-
ps
16
tIS(base)
AC150
Address and Control input setup time
(VIH/VIL(AC150) levels)
45+125
-
65+125
-
ps
16,24
tDH(base)
DQ and DM input hold time
(VIH/VIL(DC) levels)
45
-
65
-
ps
17
tDS(base)
DQ and DM input setup time
(VIH/VIL(AC) levels)
10
-
30
-
ps
17
tIPW
Address and control input pulse width
for each input
560
-
620
-
ps
25
tDIPW
DQ and DM input pulse width for
each input
360
-
400
-
ps
25
tCK
tCH, tCL (AVG)
Minmum clock cycle, DLL-off mode
tHZ(DQ)
DQ high impedance time
-
225
-
250
ps
13,14
tLZ(DQ)
DQ low impedance time
-450
225
-500
250
ps
13,14
-
225
-
250
ps
13,14
-450
225
-500
250
ps
13,14
12,13
tHZ(DQS)
tLZ(DQS)
DQS,/DQS high impedance time
RL+BL/2 reference
DQS,/DQS low impedance time
RL-1 reference
tDQSQ
DQS,/DQS to DQ skew per group,
per access
-
100
-
125
ps
tCCD
/CAS to /CAS command delay
4
-
4
-
nCK
tQH
DQ output hold time from DQS, /DQS
0.38
-
0.38
-
tCK
(avg)
12,13
tDQSCK
DQS,/DQS rising edge output access
time from rising CK,/CK
-225
225
-255
255
ps
12,13
tDQSS
DQS latch rising transitions to
associated clock edges
-0.27
0.27
-0.25
0.25
tCK
(avg)
tDQSH
DQS input high pulse width
0.45
0.55
0.45
0.55
tCK
(avg)
Jun. 2012
17/38
27,28
www.eorex.com
EM47CM1688SBB
AC Operating Test Characteristics
(VDD, VDDQ=1.5V±0.075V)
Symbol
Speed Bin
-125
(DDR3-1600)
-150
(DDR3-1333)
CL-nRCD-nRP
11-11-11
9-9-9
Parameter
Min.
Max.
Min.
Max.
Units
Notes
tDSH
DQS falling edge hold time from
rising CK
0.18
-
0.2
-
tCK
(avg)
29
tDSS
DQS falling edge setup time to rising
CK
0.18
-
0.2
-
tCK
(avg)
29
tDQSL
DQS input low pulse width
0.45
0.55
0.45
0.55
tCK
(avg)
26,28
tQSH
DQS output high time
0.40
-
0.40
-
tCK
(avg)
12,13
tQSL
DQS output low time
0.40
-
0.40
-
tCK
(avg)
12,13
tMRD
Mode register set command cycle
4
-
4
-
nCK
tMOD
Mode register set command update
delay
15
-
15
-
ns
12
-
12
-
nCK
tRPRE
Read preamble time
0.9
-
0.9
-
tCK
(avg)
13,19
tRPST
Read postamble time
0.3
-
0.3
-
tCK
(avg)
11,13
tWPRE
Write preamble time
0.9
-
0.9
-
tCK
(avg)
1
tWPST
Write postamble time
0.3
-
0.3
-
tCK
(avg)
1
Write recovery time
15
-
15
-
ns
tWR
Auto precharge write recovery +
precharge time
WR + roundup[tRP / tCK(avg)
tMPRR
Multi purpose register recovery time
1
-
1
-
nCK
tWTR
Internal write to read command delay
7.5
-
7.5
-
ns
4
-
4
-
nCK
tRTP
Internal read to precharge command
delay
7.5
-
7.5
-
ns
4
-
4
-
nCK
tCKE (min)
+1
-
tCKE (min)
+1
-
nCK
tDAL(min)
nCK
tCKESR
Minimum CKE low width for selfrefresh entry to exit
tCKSRE
Valid clock requirement after selfrefresh entry or power-down entry
10
-
10
-
ns
5
-
5
-
nCK
tCKSRX
Valid clock requirement before selfrefresh exit or power-down exit
10
-
10
-
ns
5
-
5
-
nCK
Jun. 2012
18/38
22
18
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EM47CM1688SBB
AC Operating Test Characteristics
(VDD, VDDQ=1.5V±0.075V)
Symbol
Speed Bin
-125 (DDR3-1600)
-150 (DDR3-1333)
CL-nRCD-nRP
11-11-11
9-9-9
Parameter
tXS
tXSDLL
Exit self-refresh to commands not
requiring a locked DLL
Exit self-refresh to commands
requiring a locked DLL
Units
Min.
Max.
Min.
Max.
tRFC(min)
+ 10
-
tRFC(min)
+ 10
-
ns
5
-
5
-
nCK
tDLL(min)
-
tDLL(min)
-
nCK
160
-
160
-
ns
tRFC
Auto-refresh to active/auto-refresh
command
tREFI
Average periodic refresh interval
0℃≦TC≦+85℃
-
7.8
-
7.8
µs
tREFI
Average periodic refresh interval
+85℃≦TC≦+95℃
-
3.9
-
3.9
µs
tCKE
CKE minimum high and low pulse
width
5
-
5.625
-
ns
3
tXPR
tDLLK
tPD
tXPDLL
tXP
tWRPDEN
(min)
tWRPDEN
(min)
tWRAPDEN
Exit reset from CKE high to a valid
command
Power-down entry to exit time
-
nCK
-
-
ns
5
-
5
-
nCK
512
-
512
-
nCK
tCKE(min)
9*tREFI
tCKE(min)
9*tREFI
24
-
24
-
ns
10
-
10
-
nCK
6
-
6
-
ns
3
-
3
-
nCK
Exit precharge power-down with
DLL frozen to commands requiring
a locked DLL
Exit power-down with DLL on to any
valid command; Exit precharge
power-down with DLL frozen to
commands not requiring a locked
DLL
Timing of WR command to powerdown entry
WL + 4 + [tWR / tCK(avg)]
15
2
nCK
(BL8OTF, BL8MRS, BL4OTF)
9
Timing of WR command to powerdown entry
WL + 2 + [tWR / tCK(avg)]
nCK
(BC4MRS)
Timing of WRA command to powerdown entry
Timing of WRA command to powerdown entry
(BC4MRS)
Jun. 2012
3
tRFC(min)
+ 10
DLL locking time
(BL8OTF, BL8MRS, BL4OTF)
tWRAPDEN
-
tRFC(min)
+ 10
Notes
WL + 4 +
WR + 1
-
WL + 4 +
WR + 1
-
nCK
10
WL + 2 +
WR + 1
-
WL + 2 +
WR + 1
-
nCK
10
19/38
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EM47CM1688SBB
AC Operating Test Characteristics
(VDD, VDDQ=1.5V±0.075V)
Symbol
Speed Bin
-125
(DDR3-1600)
-150
(DDR3-1333)
CL-nRCD-nRP
11-11-11
9-9-9
Parameter
Min.
Max.
Min.
Max.
Units
Notes
nCK
20,
21
tREFPDEN
Timing of REF command to powerdown entry
1
-
1
-
tMRSPDEN
Timing of MRS command to powerdown entry
tMOD
(min)
-
tMOD
(min)
-
Command pass disable delay
1
-
1
-
nCK
tACTPDEN
Timing of ACT command to powerdown entry
1
-
1
-
nCK
20
tPRPDEN
Timing of PRE command to powerdown entry
1
-
1
-
nCK
20
tRDPDEN
Timing of RD/RDA command to
power-down entry
RL + 4
+1
-
RL + 4
+1
-
nCK
-225
225
-250
250
ps
2
8.5
2
8.5
ns
0.3
0.7
0.3
0.7
tCK
(avg)
Asynchronous RTT turn-off delay
(Power-down with DLL frozen)
2
8.5
2
8.5
ns
ODTH4
ODT high time without write command
or with write command and BC4
4
-
4
-
nCK
ODTH8
ODT high time with write command
and BL8
6
-
6
-
nCK
tCPDED
tAON
tAONPD
tAOF
tAOFPD
RTT turn-on
Asynchronous RTT turn-on delay
(Power-down with DLL frozen)
RTT_Nom and RTT_WR turn-off time
from ODTLoff reference
7
8
tADC
RTT dynamic change skew
0.3
0.7
0.3
0.7
tCK
(avg)
tZQinit
Power-up and reset calibration time
512
-
512
-
nCK
tZQoper
Normal operation full calibration time
256
-
256
-
nCK
tZQCS
Normal operation short calibration time
64
-
64
-
nCK
23
tWLMRD
First DQS pulse rising edge after write
leveling mode is programmed
40
-
40
-
nCK
3
DQS./DQS delay after write leveling
mode is programmed
25
-
25
-
nCK
3
-
RL +
tCCD/2 +
2nCK-W
L
-
-
tWLDQSEN
tRTW
Read to write command delay
(BC4MRS, BC4OTF)
RL + tCCD/2
+
2nCK-WL
tRTW
Read to write command delay
(BL8MRS, BL8OTF)
RL + tCCD/2
+
2nCK-WL
-
RL +
tCCD/2 +
2nCK-W
L
tRAP
Active to read with auto precharge
command delay
tRCD min
-
tRCD
min
Jun. 2012
20/38
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EM47CM1688SBB
AC Operating Test Characteristics
(VDD, VDDQ=1.5V±0.075V)
Symbol
Speed Bin
-125 (DDR3-1600)
-150 (DDR3-1333)
CL-nRCD-nRP
11-11-11
9-9-9
Parameter
Units
Min.
Max.
Min.
Max.
tWLS
Write leveling setup time from
rising CK,/CK crossing to rising
DQS,/DQS crossing
165
-
195
-
ps
tWLH
Write leveling hold time from
rising DQS,/DQS crossing to
rising CK,/CK crossing
165
-
195
-
ps
tWLO
Write leveling output delay
0
7.5
0
9
ns
tWLOE
Write leveling output error
0
2
0
2
ns
tCK (avg)min+
tJIT(per)min
tCK (avg)max+
tJIT (per)max
tCK (avg)min+
tJIT (per)min
tCK (avg)max+
tJIT (per)max
ps
Notes
tCK (abs)
Absolute clock period
tCH (abs)
Absolute clock high pulse width
0.43
-
0.43
-
tCK
(avg)
30
tCL (abs)
Absolute clock low pulse width
0.43
-
0.43
-
tCK
(avg)
31
tJIT (per)
Clock period jitter
-70
70
-80
80
ps
Clock period jitter during DLL
locking period
-60
60
-70
70
ps
Cycle to cycle period jitter
-
140
-
160
ps
tJIT (cc,lck)
Cycle to cycle period jitter during
DLL locking period
-
120
-
140
ps
tERR (2per)
Cumulative error across 2 cycles
-103
103
-118
118
ps
tERR (3per)
Cumulative error across 3 cycles
-122
122
-140
140
ps
tERR (4per)
Cumulative error across 4 cycles
-136
136
-155
155
ps
tERR (5per)
Cumulative error across 5 cycles
-147
147
-168
168
ps
tERR (6per)
Cumulative error across 6 cycles
-155
155
-177
177
ps
tERR (7per)
Cumulative error across 7 cycles
-163
163
-186
186
ps
tERR (8per)
Cumulative error across 8 cycles
-169
169
-193
193
ps
tERR (9per)
Cumulative error across 9 cycles
-175
175
-200
200
ps
tERR (10per)
Cumulative error across 10
cycles
-180
180
-205
205
ps
tERR (11per)
Cumulative error across 11
cycles
-184
184
-210
210
ps
tERR (12per)
Cumulative error across 12
cycles
-188
188
-215
215
ps
tJIT (per,lck)
tJIT (cc)
tERR (nper)
Jun. 2012
Cumulative error across
tERR (nper)min=(1+0.68ln(n))*tJIT (per)min
n= 13,14,… 49,50 cycles
tERR (nper)max=(1+0.68ln(n))*tJIT (per)max
21/38
ps
32
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EM47CM1688SBB
AC Operating Test Characteristics
(VDD, VDDQ=1.5V±0.075V)
Symbol
Speed Bin
-125 (DDR3-1600)
-150 (DDR3-1333)
CL-nRCD-nRP
11-11-11
9-9-9
Parameter
Units
Min.
Max.
Min.
Max.
ODT to power-down entry/ exit
latency
WL–1
-
WL–1
-
nCK
ODTLon
ODT turn on latency
WL–2
WL–2
WL–2
WL–2
nCK
ODTLoff
ODT turn off latency
WL–2
WL–2
WL–2
WL–2
nCK
ODTLcnw
ODT latency for changing from
RTT_Nom to RTT_WR
WL–2
WL–2
WL–2
WL–2
nCK
ODTLcwn4
ODT latency for changing from
RTT_WR to RTT_Nom (BC4)
-
4+ODTLoff
-
4+ODTLoff
nCK
ODTLcwn8
ODT latency for changing from
RTT_WR to RTT_Nom (BL8)
-
6+ODTLoff
-
6+ODTLoff
nCK
tANPD
Notes
Note 1: Actual value dependant upon measurement level definitions which are TBD.
Note 2: Commands requiring a locked DLL are: READ (and READA) and synchronous ODT commands.
Note 3: The max values are system dependent.
Note 4: WR as programmed in mode register.
Note 5: Value must be rounded-up to next higher integer value.
Note 6: There is no maximum cycle time limit besides the need to satisfy the refresh interval, tREFI.
Note 7: ODT turn on time (min.) is when the device leaves high impedance and ODT resistance begins to turn
on. ODT turn on time (max.) is when the ODT resistance is fully on. Both are measured from ODTLon.
Note 8: ODT turn-off time (min.) is when the device starts to turn-off ODT resistance. ODT turn-off time (max.)
is when the bus is in high impedance. Both are measured from ODTLoff.
Note 9: tWR is defined in ns, for calculation of tWRPDEN it is necessary to round up tWR / tCK to the next
integer.
Note 10: WR in clock cycles as programmed in MR0.
Note 11: The maximum read postamble is bound by tDQSCK(min) plus tQSH(min) on the left side and
tHZ(DQS)max on the right side.
Note 12: Output timing deratings are relative to the SDRAM input clock. When the device is operated with input
clock jitter, this parameter needs to be derated by TBD.
Note 13: Value is only valid for RON34.
Note 14: Single ended signal parameter. Refer to the section of tLZ(DQS), tLZ(DQ), tHZ(DQS), tHZ(DQ) Notes
for definition and measurement method.
Note 15: tREFI depends on operating case temperature (Tc).
Note 16: tIS(base) and tIH(base) values are for 1V/ns command/ addresss single-ended slew rate and 2V/ns
CK, /CK differential slew rate, Note for DQ and DM signals, VREF(DC) = VREFDQ(DC). For input only pins
except RESET, VREF(DC) = VREFCA(DC). See Address / Command Setup, Hold and Derating section.
Note 17: tDS(base) and tDH(base) values are for 1V/ns DQ single-ended slew rate and 2V/ns DQS, /DQS
differential slew rate. Note for DQ and DM signals, VREF(DC)= VREFDQ(DC). For input only pins except
RESET, VREF(DC) = VREFCA(DC). See Data Setup, Hold and and Slew Rate Derating section.
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Note 18: Start of internal write transaction is defined as follows ;
For BL8 (fixed by MRS and on-the-fly, OTF) : Rising clock edge 4 clock cycles after WL.
For BC4 (on-the-fly, OTF) : Rising clock edge 4 clock cycles after WL.
For BC4 (fixed by MRS) : Rising clock edge 2 clock cycles after WL.
Note 19: The maximum read preamble is bound by tLZDQS(min) on the left side and tDQSCK(max) on the
right side.
Note 20: CKE is allowed to be registered low while operations such as row activation, precharge, auto
precharge or refresh are in progress, but power-down IDD spec will not be applied until finishing those
operation.
Note 21: Although CKE is allowed to be registered LOW after a REFRESH command once tREFPDEN(min) is
satisfied, there are cases where additional time such as tXPDLL(min) is also required.
Note 22: Defined between end of MPR read burst and MRS which reloads MPR or disables MPR function.
Note 23: One ZQCS command can effectively correct a minimum of 0.5 % (ZQCorrection) of RON and RTT
impedance error within 64 nCK for all speed bins assuming the maximum sensitivities specified in the “Output
Driver Voltage and Temperature Sensitivity” and “ODT Voltage and Temperature Sensitivity” tables. The
appropriate interval between ZQCS commands can be determined from these tables and other application
specific parameters. One method for calculating the interval between ZQCS commands, given the temperature
(Tdriftrate) and voltage (Vdriftrate) drift rates that the SDRAM is subject to in the application, is illustrated. The
interval could be defined by the following formula:
ZQCorrection
(TSens x Tdriftrate) + (VSens x Vdriftrate)
where TSens = max(dRTTdT, dRONdTM) and VSens = max(dRTTdV, dRONdVM) define the SDRAM
temperature and voltage sensitivities.
Note 24: The tIS(base) AC150 specifications are adjusted from the tIS(base) specification by adding an
additional 100 ps of derating to accommodate for the lower alternate threshold of 150 mV and another 25 ps to
account for the earlier reference point [(175 mv - 150 mV) / 1 V/ns].
Note 25: Pulse width of a input signal is defined as the width between the first crossing of VREF(DC) and the
consecutive crossing of VREF(DC).
Note 26: tDQSL describes the instantaneous differential input low pulse width on DQS - /DQS, as measured
from one falling edge to the next consecutive rising edge.
Note 27: tDQSH describes the instantaneous differential input high pulse width on DQS - /DQS, as measured
from one rising edge to the next consecutive falling edge.
Note 28: tDQSH,act + tDQSL,act = 1 tCK,act ; with tXYZ,act being the actual measured value of the respective
timing parameter in the application.
Note 29: tDSH,act + tDSS,act = 1 tCK,act ; with tXYZ,act being the actual measured value of the respective
timing parameter in the application.
Note 30: tCH(abs) is the absolute instantaneous clock high pulse width, as measured from one rising edge to
the following falling edge.
Note 31: tCL(abs) is the absolute instantaneous clock low pulse width, as measured from one falling edge to
the following rising edge.
Note 32: n = from 13 cycles to 50 cycles. This row defines 38 parameters.
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Simplified State Diagram
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1. Command Truth Table
Command
Symbol
CKE
n-1
N
/CS
/RAS
/CAS
/WE
BA0~
BA2
A10
A12,
A10~A0
Device Deselect
DES
H
H
H
X
X
X
X
X
X,X
No Operation
NOP
H
H
L
H
H
H
V
V
V,V
RD
H
H
L
H
L
H
BA
L
V,CA
Read (fixed BL8/BC4)
Read (BC4, OTF)
RDS4
H
H
L
H
L
H
BA
L
L,CA
Read (BL8, OTF)
RDS8
H
H
L
H
L
H
BA
L
H,CA
Read with Auto Precharge (fixed BL8/BC4)
RDA
H
H
L
H
L
H
BA
H
V,CA
RDAS4
H
H
L
H
L
H
BA
H
L,CA
RDAS8
H
H
L
H
L
H
BA
H
H,CA
WR
H
H
L
H
L
L
BA
L
V,CA
Write (BC4, OTF)
WRS4
H
H
L
H
L
L
BA
L
L,CA
Write (BL8,OTF)
WRS8
H
H
L
H
L
L
BA
L
H,CA
Write with Auto Precharge (fixed BL8/BC4)
WRA
H
H
L
H
L
L
BA
H
V,CA
H
H
L
H
L
L
BA
H
L,CA
H
H
L
H
L
L
BA
H
H,CA
H
H
L
L
H
H
BA
PRE
H
H
L
L
H
L
BA
L
V,V
Pre-charge All Banks
PREA
H
H
L
L
H
L
V
H
V,V
Mode Register Set
MRS
H
H
L
L
L
L
BA
Refresh
REF
H
H
L
L
L
H
V
V
V,V
Self Refresh entry
SRE
H
L
L
L
L
H
V
V
V,V
Self Refresh Exit
SRX
L
H
H
X
X
X
X
X
X,X
L
H
H
H
V
V
V,V
H
L
H
X
X
X
X
X
X,X
H
L
L
H
H
H
V
V
V,V
L
H
H
X
X
X
X
X
X,X
L
H
L
H
H
H
V
V
V,V
Read with Auto Precharge (BC4, OTF)
Read with Auto Precharge (BL8, OTF)
Write (fixed BL8/BC4)
Write with Auto Precharge (BC4, OTF)
Write with Auto Precharge (BL8, OTF)
Bank Activate
Pre-charge Single Bank
WRAS
4
WRAS
8
ACT
Power Down Entry
PDE
Power Down Exit
PDX
RA
OP Code
ZQ Calibration Long
ZQCL
H
H
L
H
H
L
X
H
X,X
ZQ Calibration Short
ZQCS
H
H
L
H
H
L
X
L
X,X
H = High level, L = Low level, X = Don't care, V = Valid, BA=Bank Address, CA=Column Address, RA=Row Address
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Note1. All DDR3 SDRAM commands are defined by states of /CS, /RAS, /CAS, /WE and CKE at the rising
edge of the clock. The MSB of BA, RA and CA are device density and configuration dependant.
Note2. /RESET is low enable command which will be used only for asynchronous reset so must be maintained
HIGH during any function.
Note3. Bank addresses (BA) determine which bank is to be operated upon. For (E)MRS BA selects an
(Extended) Mode Register.
Note4. “V” means “H or L (but a defined logic level)” and “X” means either “defined or undefined (like floating)
logic level”.
Note5. Burst reads or writes cannot be terminated or interrupted and Fixed/on-the-Fly (OTF) BL will be defined
by MRS.
Note6. The Power Down Mode does not perform any refresh operation.
Note7. The state of ODT does not affect the states described in this table. The ODT function is not available
during Self Refresh.
Note8. Self Refresh Exit is asynchronous.
Note9. VREF(Both VREFDQ and VREFCA) must be maintained during Self Refresh operation. VREFDQ
supply may be turned OFF and VREFDQ may take any value between VSS and VDD during Self
Refresh operation, provided that VREFDQ is valid and stable prior to CKE going back high and that first
Write operation or first Write Leveling Activity may not occur earlier than 512 nCK after exit from Self
Refresh.
Note10. The No Operation command should be used in cases when the DDR3 SDRAM is in an idle or wait
state. The purpose of the No Operation command (NOP) is to prevent the DDR3 SDRAM from
registerng any unwanted commands between operations. A No Operation command will not terminate
a pervious operation that is still executing, such as a burst read or write cycle.
Note11. The Deselect command performs the same function as No Operation command.
Note12. Refer to the CKE Truth Table for more detail with CKE transition.
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2. CKE Truth Table
CKE
Current State
Command (n)
Action (n)
Notes
X
Maintain power down
14,15
H
DESELECT or NOP
Power down exit
11,14
L
L
X
Maintain self refresh
15,16
L
H
DESELECT or NOP
Self refresh exit
8,12,16
Bank Active
H
L
DESELECT or NOP
Active power down entry
11,13,14
Reading
H
L
DESELECT or NOP
Power down entry
11,13,14,17
Writing
H
L
DESELECT or NOP
Power down entry
11,13,14,17
Precharging
H
L
DESELECT or NOP
Power down entry
11,13,14,17
Refreshing
H
L
DESELECT or NOP
Precharge power down entry
11
H
L
DESELECT or NOP
Precharge power down entry
11,13,14,18
H
L
REFRESH
Self refresh
9,13,18
Power Down
Self Refresh
All Banks Idle
n-1
n
/RAS, /CAS, /WE, /CS
L
L
L
For more details with all signals, see “Command Truth Table”
10
Note1. CKE (n) is the logic state of CKE at clock edge n; CKE (n-1) was the state of CKE at the previous clock
edge.
Note2. Current state is defined as the state of the DDR3 SDRAM immediately prior to clock edge n.
Note3. Command (n) is the command registered at clock edge n, and ACTION (n) is a result of Command (n),
ODT is not included here.
Note4. All states and sequences not shown are illegal or reserved unless explicitly described elsewhere in this
document.
Note5. The state of ODT does not affect the states described in this table. The ODT function is not available
during Self-Refresh.
Note6. During any CKE transition (registration of CKE H->L or CKE L->H) the CKE level must be maintained
until 1nCK prior to tCKEmin being satisfied (at which time CKE may transition again).
Note7. DESELECT and NOP are defined in the “Command Truth Table”.
Note8. On self-refresh exit DESELECT or NOP commands must be issued on every clock edge occurring
during the tXS period. Read or ODT commands may be issued only after tXSDLL is satisfied.
Note9. Self-Refresh mode can only be entered from the All Banks Idle state.
Note10. Must be a legal command as defined in the “Command Truth Table”.
Note11. Valid commands for power-down entry and exit are NOP and DESELECT only.
Note12. Valid commands for self-refresh exit are NOP and DESELECT only.
Note13. Self-Refresh can not be entered during Read or Write operations.
Note14. The Power-Down does not perform any refresh operations.
Note15. “X” means “don’t care“ (including floating around VREF) in Self-Refresh and Power-Down. It also
applies to Address pins.
Note16. VREF (Both VREFDQ and VREFCA) must be maintained during Self-Refresh operation. VREFDQ
supply may be turned OFF and VREFDQ may take any value between VSS and VDD during Self Refresh
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operation, provided that VREFDQ is valid and stable prior to CKE going back high and that first write operation
or first write Leveling activity may not occur earlier than 512 nCK after exit from Self Refresh.
Note17. If all banks are closed at the conclusion of the read, write or precharge command, then Precharge
Power-Down is entered, otherwise Active Power-Down is entered.
Note18. ‘Idle state’ is defined as all banks are closed (tRP, tDAL, etc. satisfied), no data bursts are in progress,
CKE is high, and all timings from previous operations are satisfied (tMRD, tMOD, tRFC, tZQinit, tZQoper,
tZQCS, etc.) as well as all self-refresh exit and power-down exit parameters are satisfied (tXS, tXP, tXPDLL,
etc).
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Initialization
The following sequence is required for power-up and initialization and is shown in below Figure:
1. Apply power (/RESET is recommended to be maintained below 0.2 x VDD; all other inputs may be
undefined). /RESET needs to be maintained for minimum 200 us with stable power. CKE is pulled “Low”
anytime before /RESET being de-asserted (min. time 10 ns). The power voltage ramp time between 300 mv to
VDDmin must be no greater than 200 ms; and during the ramp, VDD > VDDQ and (VDD - VDDQ) < 0.3 volts.
• VDD and VDDQ are driven from a single power converter output, AND
• The voltage levels on all pins other than VDD, VDDQ, VSS, VSSQ must be less than or equal to
VDDQ and VDD on one side and must be larger than or equal to VSSQ and VSS on the other side. In
addition, VTT is limited to 0.95 V max once power ramp is finished, AND
• Vref tracks VDDQ/2. OR
• Apply VDD without any slope reversal before or at the same time as VDDQ.
• Apply VDDQ without any slope reversal before or at the same time as VTT & Vref.
• The voltage levels on all pins other than VDD, VDDQ, VSS, VSSQ must be less than or equal to
VDDQ and VDD on one side and must be larger than or equal to VSSQ and VSS on the other side.
2. After /RESET is de-asserted, wait for another 500 us until CKE becomes active. During this time, the DRAM
will start internal state initialization; this will be done independently of external clocks.
3. Clocks (CK, /CK) need to be started and stabilized for at least 10 ns or 5 tCK (which is larger) before CKE
goes active. Since CKE is a synchronous signal, the corresponding set up time to clock (tIS) must be met. Also,
a NOP or Deselect command must be registered (with tIS set up time to clock) before CKE goes active. Once
the CKE is registered “High” after Reset, CKE needs to be continuously registered “High” until the initialization
sequence is finished, including expiration of tDLLK and tZQinit.
4. The DDR3 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 de-assertion until CKE
is registered HIGH. The ODT input signal may be in undefined state until tIS 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
tDLLK and tZQinit.
5. After CKE is being registered high, wait minimum of Reset CKE Exit time, tXPR, before issuing the first MRS
command to load mode register. (tXPR=max (tXS ; 5 x tCK)
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"
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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 tDLLK and tZQinit completed.
12. The DDR3 SDRAM is now ready for normal operation.
Reset and Power up initialization sequence
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Mode Register Definition
Mode Register MR0
The Mode Register MR0 stores the data for controlling various operating modes of DDR3 SDRAM. It controls
burst length, read burst type, CAS latency, test mode, DLL reset, WR and DLL control for precharge
power-down, which include various vendor specific options to make DDR3 SDRAM useful for various
applications. The mode register is written by asserting low on /CS, /RAS, /CAS, /WE, BA0, BA1 and BA2, while
controlling the states of address pins according to the table below.
BA2
BA1
0
BA0
00
A13
A12
0
PPD
A11
A12
Slow exit (DLL off)
0
Fast exit (DLL on)
1
BA1
BA0
MR0
0
0
MR1
0
1
MR2
1
0
MR3
1
1
A9
WR
DLL Control
(for precharge PD)
MRS Mode
A10
A8
A7
DLL
TM
A6
A5
A4
CAS Latency
A3
A2
RBT
CL
A1
A0
BL
DLL Reset
A8
Mode
A7
Read Burst Type
A3
No
0
Normal
0
Nibble sequential
0
Yes
1
Test
1
Interleave
1
BL
A1
A0
8
0
0
4 or 8 (OTF)
0
1
4
1
0
Reserved
1
1
WR for autoprecharge
A11
A10
A9
CAS Latency
A6
A5
A4
A2
Reserved
0
0
0
Reserved
0
0
0
0
5
0
0
1
Reserved
0
0
1
0
6
0
1
0
6
0
1
0
0
7
0
1
1
7
0
1
1
0
8
1
0
0
8
1
0
0
0
10
1
0
1
9
1
0
1
0
12
1
1
0
10
1
1
0
0
Reserved
1
1
1
11
1
1
1
0
Note1. BA2 and A13 are reserved for future use and must be programmed to 0 during MRS.
Note2. WR (write recovery for autoprecharge) min in clock cycles is calculated by dividing tWR (in ns) by tCK (in
ns) and rounding up to the next integer: WRmin[cycles] = Roundup(tWR[ns]/tCK[ns]). The WR value in
the mode register must be programmed to be equal or larger than WRmin. The programmed WR value
is used with tRP to determine tDAL.
Note3. In CAS latency selection, the rest of the setting bit not listed above will be reserved.
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Burst Type (A3)
Burst Length
4 (chop)
8
R/W
A2
A1
A0
Sequential Addressing, A3=0
Interleave Addressing, A3=1
R
0
0
0
0123TTTT
0123TTTT
R
0
0
1
1230TTTT
1032TTTT
R
0
1
0
2301TTTT
2301TTTT
R
0
1
1
3012TTTT
3210TTTT
R
1
0
0
4567TTTT
4567TTTT
R
1
0
1
5674TTTT
5476TTTT
R
1
1
0
6745TTTT
6745TTTT
R
1
1
1
7456TTTT
7654TTTT
W
0
V
V
0123XXXX
0123XXXX
W
1
V
V
4567XXXX
4567XXXX
R
0
0
0
01234567
01234567
R
0
0
1
12305674
10325476
R
0
1
0
23016745
23016745
R
0
1
1
30127456
32107654
R
1
0
0
45670123
45670123
R
1
0
1
56741230
54761032
R
1
1
0
67452301
67452301
R
1
1
1
74563012
76543210
W
V
V
V
01234567
01234567
Note1. In case of burst length being fixed to 4 by MR0 setting, the internal write operation starts two clock
cycles earlier than for the BL8 mode. This means that the starting point for tWR and tWTR will be pulled
in by two clocks. In case of burst length being selected on-the-fly via A12 (/BC), the internal write
operation starts at the same point in time like a burst of 8 write operation. This means that during
on-the-fly control, the starting point for tWR and tWTR will not be pulled in by two clocks.
Note2. 0...7 bit number is value of CA[2:0] that causes this bit to be the first read during a burst.
Note3. T: Output driver for data and strobes are in high impedance.
Note4. V: a valid logic level (0 or 1), but respective buffer input ignores level on input pins.
Note5. X: Don’t Care.
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CAS Latency
The CAS Latency is defined by MR0 (bits A9-A11). CAS Latency is the delay, in clock cycles, between the
internal Read command and the availability of the first bit of output data. DDR3 SDRAM does not support any
half-clock latencies. The overall Read Latency (RL) is defined as Additive Latency (AL) + CAS Latency (CL); RL
= AL + CL.
Test Mode
The normal operating mode is selected by MR0 (bit A7 = 0) and rest bits set to the desired values.
Programming bit A7 to a ‘1’ places the DDR3 SDRAM into a test mode that is only used by the DRAM factory
and should NOT be used. No operations or functionality is specified if A7 = 1.
DLL Reset
The DLL Reset bit is self-clearing, meaning that it returns back to the value of ‘0’ after the DLL reset function
has been issued. Once the DLL is enabled, a subsequent DLL Reset should be applied. Any time that the DLL
reset function is used, tDLLK must be met before any functions that require the DLL can be used (i.e., Read
commands or ODT synchronous operations).
Write Recovery
The programmed WR value MR0 (bits A9, A10, and A11) is used for the auto precharge feature along with tRP
to determine tDAL. WR (write recovery for auto-precharge) min in clock cycles is calculated by dividing tWR (in
ns) by tCK (in ns) and rounding up to the next integer: WRmin[cycles] = Roundup(tWR[ns]/ tCK[ns]). The WR
must be programmed to be equal to or larger than tWR(min).
Precharge PD DLL
MR0 (bit A12) is used to select the DLL usage during precharge power-down mode. When MR0 (A12 = 0), or
‘slow-exit’, the DLL is frozen after entering precharge power-down (for potential power savings) and upon exit
requires tXPDLL to be met prior to the next valid command. When MR0 (A12 = 1), or ‘fast-exit’, the DLL is
maintained after entering precharge power-down and upon exiting power-down requires tXP to be met prior to
the next valid command.
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Mode Register MR1
The Mode Register MR1 stores the data for enabling or disabling the DLL, output driver strength, RTT_Nom
impedance, additive latency, write leveling enable and Qoff. The Mode Register 1 is written by asserting low on
/CS, /RAS, /CAS, /WE, high on BA0, low on BA1 and BA2, while controlling the states of address pins
according to the table below.
BA2
BA1
0
BA0
A13
A12
A11
A10
A9
A8
A7
A6
A5
0
Qoff
0
0
Rtt
0
Level
Rtt
D.I.C
01
Qoff
A12
Write leveling enable
A4
A3
AL
A2
A1
A0
Rtt
D.I.C
DLL
Output Driver
Impedance Control
A5
RZQ/6
0
0
RZQ/7
0
1
A8
Reserved
1
0
Reserved
1
1
Output buffer enabled
0
Disabled
0
Output buffer disabled
1
Enabled
1
MRS Mode
BA1
BA0
Rtt_Nom
A9
A6
A2
MR0
0
0
ODT disabled
0
0
MR1
0
1
RZQ/4
0
0
MR2
1
0
RZQ/2
0
MR3
1
1
A1
DLL Enable
A0
Enable
0
Disable
1
Additive Latency
A4
A3
0
0
0
0
1
CL - 1
0
1
1
0
CL - 2
1
0
Reserved
1
1
RZQ/6
0
1
1
RZQ/12
1
0
0
RZQ/8
1
0
1
Reserved
1
1
0
Reserved
1
1
1
Note1. BA2, A8, A10 and A13 are reserved for future use (RFU) and must be programmed to 0 during MRS.
Note2. Qoff: Outputs disabled - DQs, DQSs, /DQSs.
Note3. In Write leveling Mode (MR1[bit7] = 1) with MR1[bit12] = 1, all RTT_Nom settings are allowed; in Write
Leveling Mode (MR1[bit7] = 1) with MR1[bit12] = 0, only RTT_Nom settings of RZQ/2, RZQ/4 and
RZQ/6 are allowed.
DLL Enable
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. During normal operation (DLL-on) with MR1 (A0 =
0), the DLL is automatically disabled when entering self-refresh operation and is automatically re-enabled upon
exit of self-refresh operation. Any time the DLL is enabled and subsequently reset, tDLLK clock cycles must
occur before a read or synchronous ODT 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
tDQSCK, tAON or tAOF parameters. During tDLLK, CKE must continuously be registered high. DDR3 SDRAM
does not require DLL for any Write operation, except when RTT_WR is enabled and the DLL is required for
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proper ODT operation. For more detailed information on DLL Disable operation refers to “DLL-off Mode”.
The direct ODT feature is not supported during DLL-off mode. The on-die termination resistors must be
disabled by continuously registering the ODT pin low and/or by programming the RTT_Nom bits MR1{A9,A6,A2}
to {0,0,0} via a mode register set command during DLL-off mode. The dynamic ODT feature is not supported at
DLL-off mode. User must use MRS command to set Rtt_WR, MR2 {A10, A9} = {0,0}, to disable Dynamic ODT
externally.
ODT Rtt Values
DDR3 SDRAM is capable of providing two different termination values (Rtt_Nom and Rtt_WR). The nominal
termination value Rtt_Nom is programmed in MR1. A separate value (Rtt_WR) may be programmed in MR2 to
enable a unique RTT value when ODT is enabled during writes. The Rtt_WR value can be applied during writes
even when Rtt_Nom is disabled.
Additive Latency
Additive Latency (AL) operation is supported to make command and data bus efficient for sustainable
bandwidths in DDR3 SDRAM. In this operation, It allows a read or write command (either with or without
auto-precharge) to be issued immediately after the active command. The command is held for the time of the
Additive Latency (AL) before it is issued inside the device. The Read Latency (RL) is controlled by the sum of
the AL and CAS Latency (CL) register settings. Write Latency (WL) is controlled by the sum of the AL and CAS
Write Latency (CWL) register settings.
Write Leveling
For better signal integrity, DDR3 memory module adopted fly-by topology for the commands, addresses, control
signals, and clocks. The fly-by topology has the benefit of reducing the number of stubs and their length, but it
also causes flight time skew between clock and strobe at every DRAM on the DIMM. This makes it difficult for
the Controller to maintain tDQSS, tDSS, and tDSH specification. Therefore, the DDR3 SDRAM supports a
‘write leveling’ feature to allow the controller to compensate for skew.
Output Disable
The outputs may be enabled/disabled by MR1 (bit A12). When this feature is enabled (A12 = 1), all output pins
(DQs, DQS, /DQS, etc.) are disconnected from the device, thus removing any loading of the output drivers.
For normal operation, A12 should be set to ‘0’.
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Mode Register MR2
The Mode Register MR2 stores the data for controlling refresh related features, including RTT_WR impedance
and CAS write latency (CWL). The Mode Register 2 is written by asserting low on /CS, /RAS, /CAS, /WE, high
on BA1, low on BA0 and BA2, while controlling the states of address pins according to the table below.
BA2
BA1
BA0
A13
A12
A11
0
1
0
0
0
0
A10
A9
A8
A7
A6
0
SRT
0
Self refresh temp. range
A7
Normal operating temp. range
0
Extended temp. self refresh
1
Rtt_WR
A5
A4
A3
A2
A1
CWL
A0
0
MRS Mode
BA1
BA0
Rtt_WR
A10
A9
MR0
0
0
Dynamic ODT off
0
0
MR1
0
1
RZQ/4
0
1
CAS write latency (CWL)
A6
A4
A3
5( tCK ≧ 2.5ns)
0
0
0
MR2
1
0
RZQ/2
1
0
MR3
1
1
Reserved
1
1
6 (2.5ns＞tCK ≧ 1.875ns)
0
0
1
7 (1.875ns＞ tCK ≧ 1.5ns)
0
1
0
8 (1.5ns＞ tCK ≧ 1.25ns)
0
1
1
Reserved
1
0
0
Reserved
1
0
1
Reserved
1
1
0
Reserved
1
1
1
Note1. BA2, A8, A11 ~ A13 are RFU and must be programmed to 0 during MRS.
Note2. The Rtt_WR value can be applied during writes even when Rtt_Nom is disabled. During write leveling,
Dynamic ODT is not available.
CAS Write Latency (CWL)
The CAS Write Latency is defined by MR2 (bits A3-A5). CAS Write Latency is the delay, in clock cycles,
between the internal Write command and the availability of the first bit of input data. DDR3 SDRAM does not
support any half-clock latencies. The overall Write Latency (WL) is defined as Additive Latency (AL) + CAS
Write Latency (CWL); WL = AL + CWL.
Dynamic ODT (Rtt_WR)
DDR3 SDRAM introduces a new feature “Dynamic ODT”. In certain application cases and to further enhance
signal integrity on the data bus, it is desirable that the termination strength of the DDR3 SDRAM can be
changed without issuing an MRS command. MR2 Register locations A9 and A10 configure the Dynamic ODT
settings. In Write leveling mode, only RTT_Nom is available.
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Mode Register MR3
The Mode Register MR3 controls Multi Purpose Registers (MPR). The Mode Register 3 is written by asserting
low on CS, RAS, CAS, WE, high on BA1 and BA0, and low on BA2 while controlling the states of address pins
according to the table below.
BA2
BA1
BA0
A13
A12
A11
A10
A9
A8
A7
A6
A5
A4
A3
A2
0
1
1
0
0
0
0
0
0
0
0
0
0
0
MPR
MPR Operation
A2
Normal operation
0
Dataflow from MPR
1
A1
A0
MPR Location
MRS Mode
BA1
BA0
MPR Location
A1
A0
MR0
0
0
Predefined pattern
0
0
MR1
0
1
Reserved
0
1
MR2
1
0
Reserved
1
0
MR3
1
1
Reserved
1
1
Note1. BA2, A3 - A13 are reserved for future use (RFU) and must be programmed to 0 during MRS.
Note2. The predefined pattern will be used for read synchronization.
Note3. When MPR control is set for normal operation, MR3 A[2] = 0, MR3 A[1:0] will be ignored
Multi Purpose Register (MPR)
The Multi Purpose Register (MPR) function is used to Read out a predefined system timing calibration bit
sequence. To enable the MPR, a MODE Register Set (MRS) command must be issued to MR3 Register with
bit A2 = 1. Prior to issuing the MRS command, all banks must be in the idle state (all banks precharged and
tRP met). Once the MPR is enabled, any subsequent RD or RDA commands will be redirected to the Multi
Purpose Register. When the MPR is enabled, only RD or RDA commands are allowed until a subsequent MRS
command is issued with the MPR disabled (MR3 bit A2 = 0). Power-down mode, self-refresh and any other
non-RD/RDA command is not allowed during MPR enable mode. The RESET function is supported during
MPR enable mode.
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EM47CM1688SBB
Package Description: 96Ball-FBGA
Solder ball: Lead free (Sn-Ag-Cu)
Unit: mm
6.40
A1
9
8
7
6
5
4
3
2
1
A
0.80
B
C
D
E
F
G
12.00 ± 0.10
14.00 ± 0.10
H
J
K
L
M
7.00 ± 0.05
6.00± 0.05
N
P
R
T
4.00 ± 0.05
3.20 ± 0.05
8.00 ± 0.10
0.80 ± 0.05
1.2 MAX
0.45 ± 0.05
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