AS4C256M16D3A-12BINTR - ALLIANCE MEMORY

Revision History

4Gb AS4C256M16D3A-12BIN - 96 ball FBGA PACKAGE

Revision Details Date

Rev 1.0 Preliminary datasheet May. 2016

Alliance Memory Inc. 511 Taylor Way, San Carlos, CA 94070 TEL: (650) 610-6800 FAX: (650) 620-9211

Alliance Memory Inc. reserves the right to change products or specification without notice

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256M x 16 bit DDR3 Synchronous DRAM (SDRAM)

Features

•JEDEC Standard Compliant

•Power supplies: VDD & VDDQ = +1.5V ± 0.075V

•Operating temperature: -40~95°C (TC)

•Supports JEDEC clock jitter specification

•Fully synchronous operation

•Fast clock rate: 800MHz

•Differential Clock, CK & CK#

•Bidirectional differential data strobe

- DQS & DQS#

•8 internal banks for concurrent operation

•8n-bit prefetch architecture

•Pipelined internal architecture

•Precharge & active power down

•Programmable Mode & Extended Mode registers

•Additive Latency (AL): 0, CL-1, CL-2

•Programmable Burst lengths: 4, 8

•Burst type: Sequential / Interleave

•Output Driver Impedance Control

•8192 refresh cycles / 64ms

- Average refresh period

7.8µs @ -40°C ≦TC≦ +85°C

3.9µs @ +85°C ＜TC≦ +95°C

•Write Leveling

•ZQ Calibration

•Dynamic ODT (Rtt_Nom & Rtt_WR)

•RoHS compliant

•Auto Refresh and Self Refresh

•96-ball 9 x 13 x 1.0mm FBGA package

-Pb and Halogen Free

Overview

The 4Gb Double-Data-Rate-3 DRAMs is double data

rate architecture to achieve high-speed operation. It is

internally configured as an eight bank DRAM.

The 4Gb chip is organized as 32Mbit x 16 I/Os x 8

bank devices. These synchronous devices achieve

high speed double-data-rate transfer rates of up to

1866 Mb/sec/pin for general applications.

The chip is designed to comply with all key DDR3

DRAM key features and 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 differential DQS

pair in a source synchronous fashion.

These devices operate with a single 1.5V ± 0.075V

power supply and are available in BGA packages.

Table 1. Ordering Information

Product part No Org Temperature Max Clock (MHz)

AS4C256M16D3A-12BIN 256M x 16 Industrial -40°C to 95°C 800

Package

96-ball FBGA

Table 2. Speed Grade Information

Speed Grade Clock Frequency CAS Latency tRCD (ns) tRP (ns)

DDR3-1600 800 MHz 11 13.75 13.75

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Figure 1. Ball Assignment (FBGA Top View)

…

123 789

VDDQ DQ13

VSSQ VDD

VDDQ DQ11

VSSQ VDDQ

VSS VSSQ

DQ15

VSS

DQ9

UDM

DQ0

DQ12 VDDQ

UDQS# DQ14

UDQS DQ10

DQ8 VSSQ

LDM VSSQ

VSS

VSSQ

VDDQ

VDD

VDDQ

FVDDQ DQ2 LDQS DQ1 DQ3 VSSQ

GVSSQ DQ6 LDQS# VDD VSS VSSQ

HVREFDQ VDDQ DQ4 DQ7 DQ5 VDDQ

JNC VSS RAS# CK VSS NC

KVDD CAS# CK# VDD CKE

LNC CS# WE# A10/AP ZQ

MBA0 BA2 NC VREFCA VSS

NVDD A3 A0 A12/BC # BA1

PA5 A2 A1 A4 VSS

RVDD A7 A9 A11 A6

ODT

VSS

TRESET# A13 A14 A8 VSS

VDD

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Figure 2. Block Diagram

CK#

CKE

CS#

RAS#

CAS#

WE#

DLL

CLOCK

BUFFER

COMMAND

DECODER

COLUMN

COUNTER

ADDRESS

BUFFER

A10/AP

A11

A13

A14

BA0

BA1

BA2

LDQS

LDQS#

UDQS

UDQS#

Buffer

LDM

UDM

DQ15

DQ0

ODT

32M x 16

CELL AR RAY

(BANK #0)

Row

Decoder

Column Decoder

32M x 16

CELL AR RAY

(BANK #1)

Row

Decoder

Column Decoder

32M x 16

CELL AR RAY

(BANK #2)

Row

Decoder

Column Decoder

32M x 16

CELL AR RAY

(BANK #3)

Row

Decoder

Column Decoder

32M x 16

CELL AR RAY

(BANK #4)

Row

Decoder

Column Decoder

32M x 16

CELL AR RAY

(BANK #5)

Row

Decoder

Column Decoder

32M x 16

CELL AR RAY

(BANK #6)

Row

Decoder

Column Decoder

32M x 16

CELL AR RAY

(BANK #7)

Row

Decoder

Column Decoder

CONTROL

SIGNAL

GENERATOR

A0~A9

REFRESH

COUNTER

DATA

STROBE

BUFFER

MODE

CAL

ZQCS

ZQCL

RESET#

A12/BC#

VSSQ RZQ

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Figure 3. State Diagram

This simplified State Diagram is intended to provide an overview of the possible state transitions and the

commands to control them. In particular, situations involving more than one bank, the enabling or disabling of on-die

termination, and some other events are not captured in full detail

Power

Automatic Sequence

Command Sequence

Power

applied Reset

Procedure Initialization

RESET

from any

state ZQCL

Calibration Idle

Self

Refresh

Refreshing

SRE

MRS

REF

SRX

ZQCL,ZQCS

Active

Power

Down

Activating

Precharge

Power

Down

PDE

PDX

ACT

Bank

Activating

Writing

Reading

Precharging

PDX

PDE

READ

READ A

WRITE

READ

WRITE

WRITE A

READ A

PRE, PREA

WRITE A

PRE, PREA

ACT = Active

PRE = Precharge

REF = Refresh

PREA = Precharge All

MRS = Mode Register Set

ZQCL = ZQ Calibration Long

Read = RD, RDS4, RDS8

Read A = RDA, RDAS4, RDAS8

Write = WR, WRS4, WRS8

Write A = WRA, WRAS4, WRAS8

RESET = Start RESET Procedure

ZQCS = ZQ Calibration Short

PDE = Enter Power-down

PDX = Exit Power-down

SRE = Self-Refresh entry

SRX = Self-Refresh exit

MPR = Multi-Purpose Register

Reading

MRS,MPR,

Write

Leveling

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Ball Descriptions

Table 3. Ball Descriptions

Symbol Type Description

CK, CK# Input Differential Clock: CK and CK# are driven by the system clock. All SDRAM input signals

are sampled on the crossing of 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).

CKE Input

Clock Enable: CKE activates (HIGH) and deactivates (LOW) the CK signal. If CKE goes

LOW synchronously with clock, the internal clock is suspended from the next clock cycle

and the state of output and burst address is frozen as long as the CKE remains LOW.

When all banks are in the idle state, deactivating the clock controls the entry to the Power

Down and Self Refresh modes.

BA0-BA2 Input

Bank Address: BA0-BA2 define to which bank the BankActivate, Read, Write, or Bank

Precharge command is being applied.

A0-A14 Input

Address Inputs: A0-A14 are sampled during the BankActivate command (row address

A0-A14) and Read/Write command (column address A0-A9 with A10 defining Auto Precharge).

A10/AP Input

Auto-Precharge: A10 is sampled during Read/Write commands to determine whether

Autoprecharge should be performed to the accessed bank after the Read/Write operation.

(HIGH: Autoprecharge; LOW: no Autoprecharge). A10 is sampled during a Precharge

command to determine whether the Precharge applies to one bank (A10 LOW) or all

banks (A10 HIGH).

A12/BC# Input

Burst Chop: A12/BC# 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).

CS# Input

Chip Select: CS# enables (sampled LOW) and disables (sampled HIGH) the command

decoder. All commands are masked when CS# is sampled HIGH. It is considered part of

the command code.

RAS# Input

Row Address Strobe: The RAS# signal defines the operation commands in conjunction

with the CAS# and WE# signals and is latched at the crossing of positive edges of CK

and negative edge of CK#. When RAS# and CS# are asserted "LOW" and CAS# is

asserted "HIGH," either the BankActivate command or the Precharge command is

selected by the WE# signal. When the WE# is asserted "HIGH," the BankActivate

command is selected and the bank designated by BA is turned on to the active state.

When the WE# is asserted "LOW," the Precharge command is selected and the bank

designated by BA is switched to the idle state after the precharge operation.

CAS# Input Column Address Strobe: The CAS# signal defines the operation commands in

conjunction with the RAS# and WE# signals and is latched at the crossing of positive

edges of CK and negative edge of CK#. When RAS# is held "HIGH" and CS# is asserted

"LOW," the column access is started by asserting CAS# "LOW." Then, the Read or Write

command is selected by asserting WE# “HIGH " or “LOW".

WE# Input

Write Enable: The WE# signal defines the operation commands in conjunction with the

RAS# and CAS# signals and is latched at the crossing of positive edges of CK and

negative edge of CK#. The WE# input is used to select the BankActivate or Precharge

command and Read or Write command.

LDQS,

LDQS#

UDQS

UDQS#

Input /

Output

Bidirectional Data Strobe: Specifies timing for Input and Output data. Read Data Strobe

is edge triggered. Write Data Strobe provides a setup and hold time for data and DQM.

LDQS is for DQ0~7, UDQS is for DQ8~15. The data strobes LDOS and UDQS are paired

with LDQS# and UDQS# to provide differential pair signaling to the system during both

reads and writes.

LDM,

UDM

Input Data Input Mask: Input data is masked when DM is sampled HIGH during a write cycle.

LDM masks DQ0-DQ7, UDM masks DQ8-DQ15.

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DQ0 - DQ15 Input /

Output Data I/O: The DQ0-DQ15 input and output data are synchronized with positive and

negative edges of DQS and DQS#. TheI/Os are byte-maskable during Writes.

ODT Input

On Die Termination: ODT (registered HIGH) enables termination resistance internal to

the DDR3 SDRAM. When enabled, ODT is applied to each DQ, DQS, DQS#. The ODT

pin will be ignored if Mode-registers, MR1and MR2, are programmed to disable RTT.

RESET# Input

Active Low Asynchronous Reset: Reset is active when RESET# is LOW, and inactive

when RESET# is 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

VDD Supply Power Supply: +1.5V ±0.075V

VSS Supply Ground

VDDQ Supply DQ Power: +1.5V ±0.075V.

VSSQ Supply DQ Ground

VREFCA Supply Reference voltage for CA

VREFDQ Supply Reference voltage for DQ

ZQ Supply

Reference pin for ZQ calibration.

NC -

No Connect: These pins should be left unconnected.

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Operation Mode Truth Table

Table 4. Truth Table (Note (1), (2))

Command State

CKEn-1(3) CKEnDM BA0-2 A10/AP A0-9, 11, 13-14 A12/BC# CS# RAS# CAS# WE#

BankActivate Idle(4) H H X V Row address L L H H

Single Bank Precharge Any H H X V L V V L L H L

All Banks Precharge Any H H X V H V V L L H L

Write (Fixed BL8 or BC4) Active(4) H H X V L V V L H L L

Write (BC4, on the fly) Active(4) H H X V L V L L H L L

Write (BL8, on the fly) Active(4) H H X V L V H L H L L

Write with Autoprecharge

(Fixed BL8 or BC4) Active(4) H H X V H V V L H L L

Write with Autoprecharge

(BC4, on the fly) Active(4) H H X V H V L L H L L

Write with Autoprecharge

(BL8, on the fly) Active(4) H H X V H V H L H L L

Read (Fixed BL8 or BC4) Active(4) H H X V L V V L H L H

Read (BC4, on the fly) Active(4) H H X V L V L L H L H

Read (BL8, on the fly) Active(4) H H X V L V H L H L H

Read with Autoprecharge

(Fixed BL8 or BC4) Active(4) H H X V H V V L H L H

Read with Autoprecharge

(BC4, on the fly) Active(4) H H X V H V L L H L H

Read with Autoprecharge

(BL8, on the fly) Active(4) H H X V H V H L H L H

(Extended) Mode Register Set Idle H H X V OP code L L L L

No-Operation Any

H H X V V V V L H H H

Device Deselect Any H H X X X X X H X X X

Refresh Idle

H H X V V V V L L L H

SelfRefresh Entry Idle H L X V V V V L L L H

X X X X H X X X

SelfRefresh Exit Idle L H X V V V V L H H H

X X X X H X X X

Power Down Mode Entry Idle H L X V V V V L H H H

X X X X H X X X

Power Down Mode Exit Any L H X V V V V L H H H

Data Input Mask Disable Active H X L X X X X X X X X

Data Input Mask Enable(5) Active

H X H X X X X X X X X

ZQ Calibration Long Idle H H X X H X X L H H L

ZQ Calibration Short Idle H H X X L X X L H H L

NOTE 1: V=Valid data, X=Don't Care, L=Low level, H=High level

NOTE 2: CKEn signal is input level when commands are provided.

NOTE 3: CKEn-1 signal is input level one clock cycle before the commands are provided.

NOTE 4: These are states of bank designated by BA signal.

NOTE 5: LDM and UDM can be enabled respectively.

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Functional Description

The DDR3 SDRAM is a high-speed dynamic random access memory internally configured as an eight-bank DRAM.

The DDR3 SDRAM uses an 8n prefetch architecture to achieve high speed operation. The 8n Prefetch architecture

is combined with an interface designed to transfer two data words per clock cycle at the I/O pins. A single read or

write operation for the DDR3 SDRAM consists of a single 8n-bit wide, four clock data transfer at the internal DRAM

core and two corresponding n-bit wide, one-half clock cycle data transfers at the I/O pins.

Read and write operation to the DDR3 SDRAM are burst oriented, start at a selected location, and continue for a

burst length of eight or a ‘chopped’ burst of four in a programmed sequence. Operation begins with the registration

of an Active command, which is then followed by a Read or Write command. The address bits registered coincident

with the Active command are used to select the bank and row to be activated (BA0-BA2 select the bank; A0-A14

select the row). The address bit registered coincident with the Read or Write command are used to select the

starting column location for the burst operation, determine if the auto precharge command is to be issued (via A10),

and select BC4 or BL8 mode ‘on the fly’ (via A12) if enabled in the mode register.

Prior to normal operation, the DDR3 SDRAM must be powered up and initialized in a predefined manner. The

following sections provide detailed information covering device reset and initialization, register definition, command

descriptions and device operation.

Figure 4. Reset and Initialization Sequence at Power-on Ramping

CK#

VDDQ

Tb Tc Td Te Tf Tg Th Ti TjTa

RESET#

tCKSRX

T=200µs T=500µs

tDLLK

tXPR tMRD tMRD tMRD tMOD tZQinit

MRSNote 1 MRS MRS MRS ZQCL Note 1 VALID

MR3MR2 MR1 MR0 VALID

VALID

VDD

CKE

ODT

RTT

Tmin=10ns tIS

tIS

Static LOW in case RTT_Nom is enabled at time Tg, otherwise static HIGH or LOW

Don't CareTIME BREAK

NOTE 1. From time point Td until Tk NOP or DES commands must be applied between MRS and ZQCL commands.

COMMAND

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zPower-up and Initialization

The Following sequence is required for POWER UP and Initialization

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 200us with stable power. CKE is pulled “Low” anytime before

RESET# being de-asserted (min. time 10ns). The power voltage ramp time between 300mV to VDDmin must be

no greater than 200ms; 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 0.95V max once power ramp is finished, AND

-Vref tracks VDDQ/2.

- 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 500us until CKE become active. During this time, the DRAM will

start internal state initialization; this will be done independently of external clocks.

3. Clock (CK, CK#) need to be started and stabilized for at least 10ns or 5tCK (which is larger) before CKE goes

active. Since CKE is a synchronous signal, the corresponding set up time to clock (tIS) must be meeting. Also a

NOP or Deselect command must be registered (with tIS set up time to clock) before CKE goes active. Once the

CKE 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 DRAM will keep its on-die termination in high impedance state as long as RESET# is asserted.

Further, the DRAM 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 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 being registered high, wait minimum of Reset CKE Exit time, tXPR, before issuing the first MRS

command to load mode register.(tXPR=max (tXS, 5tCK))

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 and 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-BA2)

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.

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zReset Procedure at Stable Power

The following sequence is required for RESET at no power interruption initialization.

1. Asserted RESET below 0.2*VDD anytime when reset is needed (all other inputs may be undefined). RESET

needs to be maintained for minimum 100ns. CKE is pulled “Low” before RESET being de-asserted (min. time

10ns).

2. Follow Power-up Initialization Sequence step 2 to 11.

3. The Reset sequence is now completed. DDR3 SDRAM is ready for normal operation.

Figure 5. Reset Procedure at Power Stable Condition

CK#

VDDQ

Tb Tc Td Te Tf Tg Th Ti TjTa

RESET#

tCKSRX

T=100ns T=500µs

tDLLK

tXPR tMRD tMRD tMRD tMOD tZQinit

MRSNote 1 MRS MRS MRS ZQCL Note 1 VALID

MR3MR2 MR1 MR0 VALID

VALID

VDD

COMMAND

CKE

ODT

RTT

tIS

Static LOW in case RTT_Nom is enabled at time Tg, otherwise static HIGH or LOW

Don't CareTIME BREAK

NOTE 1. From time point Td until Tk NOP or DES commands must be applied between MRS and ZQCL commands.

Tmin=10ns

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zProgramming the Mode Registers

For application flexibility, various functions, features, and modes are programmable in four Mode Registers,

provided by the DDR3 SDRAM, as user defined variables and they must be programmed via a Mode Register Set

(MRS) command. As the default values of the Mode Registers are not defined, contents of Mode Registers must be

fully initialized and/or re-initialized, i.e., written, after power up and/or reset for proper operation. Also the contents of

the Mode Registers can be altered by re-executing the MRS command during normal operation. When

programming the mode registers, even if the user chooses to modify only a sub-set of the MRS fields, all address

fields within the accessed mode register must be redefined when the MRS command is issued. MRS command and

DLL Reset do not affect array contents, which mean these commands can be executed any time after power-up

without affecting the array contents.

The mode register set command cycle time, tMRD is required to complete the write operation to the mode register

and is the minimum time required between two MRS commands shown in Figure of tMRD timing.

Figure 6. tMRD timing

T1 T2 Ta0 Ta1 Tb0 Tb1 Tb2 Tc0 Tc1T0 Tc2

VALID

tMRD

ODTLoff + 1

Don't CareTIME BREAK

VALIDVALID VALID MRS NOP/DES NOP/DES MRS NOP/DES NOP/DES VALID VALID

VALIDVALID VALID VALID VALID VALID VALID VALID VALID VALID VALID

Old Settings Updating Settings

VALIDVALID

VALIDVALID VALID VALID VALID VALID VALID VALID VALID VALID VALID

tMOD

New Settings

RTT_Nom ENABLED prior and/or after MRS command

RTT_Nom DISABLED prior and after MRS command

CK#

ADDRESS

COMMAND

CKE

Settings

ODT

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The MRS command to Non-MRS command delay, tMOD, is require for the DRAM to update the features except

DLL reset, and is the minimum time required from an MRS command to a non-MRS command excluding NOP and

DES shown in Figure of tMOD timing.

Figure 7. tMOD timing

CK#

T1 T2 Ta0 Ta1 Ta2 Ta3 Ta4 Tb0 Tb1T0

ADDRESS

Tb2

VALID

COMMAND

CKE

Settings

ODT

ODTLoff + 1

Don't CareTIME BREAK

VALIDVALID VALID MRS NOP/DES NOP/DES NOP/DES NOP/DES NOP/DES VALID VALID

VALIDVALID VALID VALID VALID VALID VALID VALID VALID VALID VALID

Old Settings Updating Settings

VALIDVALID

VALIDVALID VALID VALID VALID VALID VALID VALID VALID VALID VALID

tMOD

New Settings

RTT_Nom ENABLED prior and/or after MRS command

RTT_Nom DISABLED prior and after MRS command

The mode register contents can be changed using the same command and timing requirements during normal

operation as long as the DRAM is in idle state, i.e., all banks are in the precharged state with tRP satisfied, all data

bursts are completed and CKE is high prior to writing into the mode register. The mode registers are divided into

various fields depending on the functionality and/or modes.

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zMode Register MR0

The mode-register MR0 stores 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 DRAM 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 following figure.

Table 5. Mode Register Bitmap

BA2 BA1 BA0 A14 A13 A12 A11 A10 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0 Address Field

0*1 0 0

0*1 0

*1 PPD WR DLL TM CAS Latency RBT CL BL Mode Register (0)

BA1 BA0 MRS mode A7 Mode A3 Read Burst Type A1 A0 BL

0 0 MR0 0 Normal 0 Nibble Sequential 0 0 8 (Fixed)

0 1 MR1 1 Test 1 Interleave 0 1

BC4 or 8 (on the fly)

1 0 MR2 1 0 BC4 (Fixed)

1 1 MR3

1 1 Reserved

A11 A10 A9 WR (cycles)

0 0 0 Reserved A6 A5 A4 A2 CAS Latency

0 0 1 5*2 0000 Reserved

0 1 0 6*2 0010 5

0 1 1 7*2 0100 6

1 0 0 8*2 0110 7

1 0 1 10*2 1000 8

1 1 0 12*2 1010 9

1 1 1 14*2 1100 10

1110 11

A12 DLL Control for Precharge PD 0001

0 Slow exit (DLL off) 0011

A8 DLL Reset 1 Fast exit (DLL on) 0101 Reserved

0 No 0111 Reserved

1 Yes 1001 Reserved

1011 Reserv

1101 Reserv

1111 Reserv

Note 1: Reserved for future use and must be set to 0 when programming the MR.

Note 2: WR (write recovery for autoprecharge) min in clock cycles is calculated by dividing tWR (ns) by tCK (ns) and

rounding up to the next integer WRmin [cycles] =Roundup (tWR / tCK). The 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.

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Reserved

- Burst Length, Type, and Order

Accesses within a given burst may be programmed to sequential or interleaved order. The burst type is selected via

bit A3 as shown in the MR0 Definition as above figure. The ordering of access within a burst is determined by the

burst length, burst type, and the starting column address. The burst length is defined by bits A0-A1. Burst lengths

options include fix BC4, fixed BL8, and on the fly which allow BC4 or BL8 to be selected coincident with the

registration of a Read or Write command via A12/BC#

Table 6. Burst Type and Burst Order

Starting Column

Address

Burst Length Read

Write A2 A1 A0

Sequential

A3=0

Interleave

A3=1 Note

0 0 0 0, 1, 2, 3, T, T, T, T 0, 1, 2, 3, T, T, T, T

0 0 1 1, 2, 3, 0, T, T, T, T 1, 0, 3, 2, T, T, T, T

0 1 0 2, 3, 0, 1, T, T, T, T 2, 3, 0, 1, T, T, T, T

0 1 1 3, 0, 1, 2, T, T, T, T 3, 2, 1, 0, T, T, T, T

1 0 0 4, 5, 6, 7, T, T, T, T 4, 5, 6, 7, T, T, T, T

1 0 1 5, 6, 7, 4, T, T, T, T 5, 4, 7, 6, T, T, T, T

1 1 0 6, 7, 4, 5, T, T, T, T 6, 7, 4, 5, T, T, T, T

Read

1 1 1 7, 4, 5, 6, T, T, T, T 7, 6, 5, 4, T, T, T, T

1, 2, 3

0 V V 0, 1, 2, 3, X, X, X, X 0, 1, 2, 3, X, X, X, X

Chop

Write 1 V V 4, 5, 6, 7, X, X, X, X 4, 5, 6, 7, X, X, X, X 1, 2, 4, 5

0 0 0 0, 1, 2, 3, 4, 5, 6, 7 0, 1, 2, 3, 4, 5, 6, 7

0 0 1 1, 2, 3, 0, 5, 6, 7, 4 1, 0, 3, 2, 5, 4, 7, 6

0 1 0 2, 3, 0, 1, 6, 7, 4, 5 2, 3, 0, 1, 6, 7, 4, 5

0 1 1 3, 0, 1, 2, 7, 4, 5, 6 3, 2, 1, 0, 7, 6, 5, 4

1 0 0 4, 5, 6, 7, 0, 1, 2, 3 4, 5, 6, 7, 0, 1, 2, 3

1 0 1 5, 6, 7, 4, 1, 2, 3, 0 5, 4, 7, 6, 1, 0, 3, 2

1 1 0 6, 7, 4, 5, 2, 3, 0, 1 6, 7, 4, 5, 2, 3, 0, 1

Read

1 1 1 7, 4, 5, 6, 3, 0, 1, 2 7, 6, 5, 4, 3, 2, 1, 0

Write V V V 0, 1, 2, 3, 4, 5, 6, 7 0, 1, 2, 3, 4, 5, 6, 7 2, 4

Note 1: 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.

Note 2: 0~7 bit number is value of CA[2:0] that causes this bit to be the first read during a burst.

Note 3: T: Output driver for data and strobes are in high impedance.

Note 4: V: a valid logic level (0 or 1), but respective buffer input ignores level on input pins.

Note 5: X: Don’t Care.

- CAS Latency

The CAS Latency is defined by MR0 (bit A2, A4~A6) as shown in the MR0 Definition figure. 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 (bit7=0) and all other bits set to the desired values shown in the

MR0 definition figure. Programming bit A7 to a ‘1’ places the DDR3 SDRAM into a test mode that is only used by

the DRAM manufacturer and should not be used. No operations or functionality is guaranteed if A7=1.

- DLL Reset

The DLL Reset bit is self-clearing, meaning 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. Anytime 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.)

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- 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 (ns) by

tCK (ns) and rounding up to the next integer: WR min [cycles] = Roundup (tWR [ns]/tCK [ns]). The WR must be

programmed to be equal 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.

zMode Register MR1

The Mode Register MR1 stores the data for enabling or disabling the DLL, output 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 and low on BA1 and BA2, while controlling the states of address pins according to the

following figure.

Table 7. Extended Mode Register EMR (1) Bitmap

BA2 BA1 BA0 A14 A13 A12 A11 A10 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0 Address Field

0*1 0 1

0*1 0*1 Qoff 0*1 0*1 Rtt_Nom 0*1 Level Rtt_Nom D.I.C AL Rtt_Nom D.I.C DLL Mode Register (1)

BA1 BA0 MRS mode A4 A3 Additive Latency A0 DLL Enable

0 0 MR0 0 0 0 (AL disabled) 0 Enable

0 1 MR1 0 1 CL – 1 1 Disable

1 0 MR2 1 0 CL – 2

1 1 MR3 1 1 Reserved

A12 Qoff *2

0 Output buffer enabled A9 A6 A2 Rtt_Nom

1 Output buffer disabled 0 0 0 Rtt_Nom disabled

001 RZQ/4

A7 Write leveling enable 010 RZQ/2

0 Disabled 0 1 1 RZQ/6

1 Enabled 1 0 0 RZQ/12

Note: RZQ = 240 Ω 101 RZQ/

A5 A1

Output Driver Impedance Control 1 1 0 Reserved

0 0 RZQ/6 1 1 1 Reserved

0 1 RZQ/7 Note: RZQ = 240 Ω

1 0 Reserved

1 1 Reserved

Note 1: Reserved for future use and must be set to 0 when programming the MR.

Note 2: Outputs disabled - DQs, DQSs, DQS#s.

Note 3: 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.

Note 4: If RTT_Nom is used during Writes, only the values RZQ/2, RZQ/4 and RZQ/6 are allowed.

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- 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. During normal operation (DLL-on) with MR1 (A0=0),

the DLL is automatically disabled when entering Self-Refresh operation and is automatically re-enable 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, expect when RTT_WR is enabled and the DLL is required for proper ODT operation. For

more detailed information on DLL Disable operation are described in 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

- Output Driver Impedance Control

The output driver impedance of the DDR3 SDRAM device is selected by MR1 (bit A1 and A5) as shown in MR1

definition figure.

- 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 programmable in MR1. A separate value (Rtt_WR) may be programmable 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 (AL)

Additive Latency (AL) operation is supported to make command and data bus efficient for sustainable bandwidth in

DDR3 SDRAM. In this operation, the DDR3 SDRAM 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. A summary of the AL register options are shown in MR.

- 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 benefits from reducing number of stubs and their length but in other

aspect, causes flight time skew between clock and strobe at every DRAM on DIMM. It makes difficult for the

Controller to maintain tDQSS, tDSS, and tDSH specification. Therefore, the controller should support ‘write leveling’

in DDR3 SDRAM to compensate for skew.

- Output Disable

The DDR3 SDRAM outputs maybe enable/disabled by MR1 (bit 12) as shown in MR1 definition. When this feature

is enabled (A12=1) all output pins (DQs, DQS, DQS#, etc.) are disconnected from the device removing any loading

of the output drivers. This feature may be useful when measuring modules power for example. For normal operation

A12 should be set to ‘0’.

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zMode Register MR2

The Mode Register MR2 stores the data for controlling refresh related features, Rtt_WR impedance, and CAS write

latency. The Mode Register 2 is written by asserting low on CS#, RAS#, CAS#, WE#, high on BA1 and low on BA0

and BA2, while controlling the states of address pins according to the table below.

Table 8. Extended Mode Register EMR (2) Bitmap

BA2 BA1 BA0 A14 A13 A12 A11 A10 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0 Address Field

0*1 1 0 0*1 Rtt_WR 0*1 SRT ASR CWL PASR Mode Register (2)

BA1 BA0 MRS mode A6 Auto Self-Refresh (ASR)

0 0 MR0 0 Manual SR Reference (SRT)

0 1 MR1 1 ASR enable (Optional)

1 0 MR2

1 1 MR3

A10 A9 RTT_WR

0 0

Dynamic ODT off (Write does not affect Rtt value) A2 A1 A0 Partial Array Self-Refresh (Optional)

0 1 RZQ/4 0 0 0 Full Array

1 0 RZQ/2 001 HalfArray (BA[2:0]=000,001,010,&011)

1 1 Reserved 010 Quarter Array (BA[2:0]=000,&001)

011 1/8th Array (BA[2:0]=000)

100

3/4 Array (BA[2:0]=010,011,100.101,110,&111)

101 HalfArray (BA[2:0]=100,101,110,&111)

110 Quarter Array (BA[2:0]=110,&111)

111 1/8th Array (BA[2:0]=111)

A7 Self-Refresh Temperature (SRT) Range A5 A4 A3 CAS write Latency (CWL)

0 Normal operating temperature range 000 5 (tCK(avg)≧2.5ns)

1 Extended (optional) operating temperature range 001 6 (2.5ns＞tCK(avg)≧1.875ns)

010 7 (1.875ns＞tCK(avg)≧1.5ns)

011 8 (1.5ns＞tCK(avg)≧1.25ns)

100 9 (1.25ns＞tCK(avg)≧1.07ns)

1 0 1 Reserved

1 1 0 Reserved

1 1 1 Reserved

Note 1: BA2 and A8, A11~ A14 are RFU and must be programmed to 0 during MRS.

Note 2: The Rtt_WR value can be applied during writes even when Rtt_Nom is disabled.

During write leveling, Dynamic ODT is not available.

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- Partial Array Self-Refresh (PASR)

Optional in DDR3 SDRAM: Users should refer to the DRAM supplier data sheet and/or the DIMM SPD to determine

if DDR3 SDRAM devices support the following options or requirements referred to in this material.

If PASR (Partial Array Self-Refresh) is enabled, data located in areas of the array beyond the specified address

range will be lost if Self-Refresh is entered. Data integrity will be maintained if tREFI conditions are met and no Self-

Refresh command is issued.

- CAS Write Latency (CWL)

The CAS Write Latency is defined by MR2 (bits A3-A5) shown in MR2. 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 DRAM 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.

For more information on the supported CWL and AL settings based on the operating clock frequency, refer to

“Standard Speed Bins”. For detailed Write operation refer to “WRITE Operation”.

- Auto Self-Refresh (ASR) and Self-Refresh Temperature (SRT)

DDR3 SDRAM must support Self-Refresh operation at all supported temperatures. Applications requiring Self-

Refresh operation in the Extended Temperature Range must use the ASR function or program the SRT bit

appropriately.

Optional in DDR3 SDRAM: Users should refer to the DRAM supplier data sheet and/or the DIMM SPD to determine

if DDR3 SDRAM devices support the following options or requirements referred to in this material. For more details

refer to “Extended Temperature Usage”. DDR3 SDRAMs must support Self-Refresh operation at all supported

temperatures. Applications requiring Self-Refresh operation in the Extended Temperature Range must use the

optional ASR function or program the SRT bit appropriately.

- 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.

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. For details on Dynamic ODT operation, refer to “Dynamic ODT”.

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zMode Register MR3

The Mode Register MR3 controls Multi-purpose registers. 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

Table 9. Extended Mode Register EMR (3) Bitmap

BA2 BA1 BA0 A14 A13 A12 A11 A10 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0 Address Field

0*1 1 1 0*1 MPR MPR Loc Mode Register (3)

BA1

BA0

MRS

mode A2 MPR

A1 A0

MPR location

0 0 MR0 0 Normal operation

*3 0 0

Predefined pattern *2

0 1 MR1 1 Dataflow from MPR 0 1 RFU

1 0 MR2 1 0 RFU

1 1 MR3 1 1 RFU

Note 1: BA2, A3 - A14 are RFU and must be programmed to 0 during MRS.

Note 2: The predefined pattern will be used for read synchronization.

Note 3: When MPR control is set for normal operation (MR3 A[2] = 0) then MR3 A[1:0] will be ignored.

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Table 10. Absolute Maximum DC Ratings

Symbol Parameter Values Unit Note

VDD Voltage on VDD pin relative to Vss -0.4 ~ 1.8 V 1,3

VDDQ Voltage on VDDQ pin relative to Vss -0.4 ~ 1.8 V 1,3

VIN, VOUT Voltage on any pin relative to Vss -0.4 ~ 1.8 V 1

TSTG Storage temperature -55~100 °C1,2

NOTE1: Stresses greater than those listed under "Absolute Maximum Ratings" may cause permanent damage to the

device.This is a stress rating only and functional operation of the device at these or any other conditions above

those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating

conditions for extended periods may affect reliability.

NOTE2: Storage Temperature is the case surface temperature on the center/top side of the DRAM.

NOTE3: VDD and VDDQ must be within 300mV of each other at all times; and Vref must be not greater than 0.6VDDQ,

when VDD and VDDQ are less than 500mV; Vref may be equal to or less than 300mV.

Table 11. Temperature Range

Symbol Parameter Values Unit Note

TOPER Industrial Temperature Range -40~95 °C1-4

NOTE1: Operating temperature is the case surface temperature on center/top of the DRAM.

NOTE2: The operating temperature range is the temperature where all DRAM specification will be supported.

Outside of this temperature range, even if it is still within the limit of stress condition, some deviation on portion of

operating specification may be required. During operation, the DRAM case temperature must be maintained

between 0-85°C under all other specification parameter. Supporting 0 - 85 °C with full JEDEC AC & DC specifications.

NOTE3: Some applications require operation of the DRAM in the Extended Temperature Range between 85 °C and 95 °C

case temperature. Full specifications are guaranteed in this range, but the following additional apply.

a) Refresh commands must be doubled in frequency, therefore, reducing the Refresh interval tREFI to 3.9us. It is

also possible to specify a component with 1x refresh (tREFI to 7.8us) in the Extended Temperature Range.

b) If Self-Refresh operation is required in the Extended Temperature Range, then it is mandatory to either use the

Manual Self-Refresh mode with Extended Temperature Range capability (MR2 A6=0 and MR2 A7=1) or enable

the optional Auto Self-Refresh mode (MR2 A6=1 and MR2 A7=0).

NOTE4: During Industrial Temperature Operation Range, the DRAM case temperature must be maintained between

-40°C~95°C under all operating Conditions.

Table 12. Recommended DC Operating Conditions

Symbol Parameter Min. Typ. Max.

Unit Note

VDD Power supply voltage 1.425 1.5 1.575 V 1,2

VDDQ Power supply voltage for output 1.425 1.5 1.575 V 1,2

NOTE1: Under all conditions VDDQ must be less than or equal to VDD.

NOTE2: VDDQ tracks with VDD. AC parameters are measured with VDD and VDDQ tied together.

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Table 13. Single-Ended AC and DC Input Levels for Command and Address

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Symbol Parameter Min. Max.

Unit Note

VIH.CA(DC100) DC input logic high V

REF+0.1 VDD V 1,5

VIL.CA(DC100) DC input logic low VSS V

REF-0.1 V 1,6

VIH.CA(AC175) AC input logic high VREF+0.175 - V 1,2

VIL.CA(AC175) AC input logic low - VREF-0.175 V 1,2

VIH.CA(AC150) AC input logic high VREF+0.15 - V 1,2

VIL.CA(AC150) AC input logic low - VREF-0.15 V 1,2

VIH.CA(AC135) AC input logic high - -

V 1,2

VIL.CA(AC135) AC input logic low - -

V 1,2

VRefCA(DC) Reference Voltage for ADD, CMD inputs 0.49xVDD 0.51xVDD V 3,4

NOTE 1: For input only pins except RESET#. Vref = VrefCA(DC).

NOTE 2: See “Overshoot and Undershoot Specifications”.

NOTE 3: The ac peak noise on VRef may not allow VRef to deviate from VRefCA(DC) by more than +/-1% VDD.

NOTE 4: For reference: approx. VDD/2 +/- 15 mV.

NOTE 5: VIH(dc) is used as a simplified symbol for VIH.CA(DC100)

NOTE 6: VIL(dc) is used as a simplified symbol for VIL.CA(DC100)

NOTE 7: VIH(ac) is used as a simplified symbol for VIH.CA(AC175), VIH.CA(AC150), VIH.CA(AC135) and VIH.CA(AC175)

value is used when Vref + 0.175V is referenced, VIH.CA(AC150) value is used when Vref + 0.150V is referenced,

VIH.CA(AC135) value is used when Vref + 0.135V is referenced.

NOTE 8: VIL(ac) is used as a simplified symbol for VIL.CA(AC175), VIL.CA(AC150), VIL.CA(AC135) and VIL.CA(AC175)

value is used when Vref - 0.175V is referenced, VIL.CA(AC150) value is used when Vref - 0.150V is referenced,

VIL.CA(AC135) value is used when Vref - 0.135V is referenced.

Table 14. Single-Ended AC and DC Input Levels for DQ and DM

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Symbol Parameter Min. Max.

Unit Note

VIH.DQ(DC100) DC input logic high V

REF+0.1 VDD V 1,5

VIL.DQ(DC100) DC input logic low VSS V

REF-0.1 V 1,6

VIH.DQ(AC150) AC input logic high VREF+0.15 - V 1,2

VIL.DQ(AC150) AC input logic low - VREF-0.15 V 1,2

VIH.DQ(AC135) AC input logic high - -

V 1,2

VIL.DQ(AC135) AC input logic low - -

V 1,2

VRefDQ(DC) Reference Voltage for DQ, DM inputs 0.49xVDD 0.51xVDD V 3,4

NOTE 1: Vref = VrefDQ(DC).

NOTE 2: See “Overshoot and Undershoot Specifications”.

NOTE 3: The ac peak noise on VRef may not allow VRef to deviate from VRefDQ(DC) by more than +/-1% VDD.

NOTE 4: For reference: approx. VDD/2 +/- 15 mV.

NOTE 5: VIH(dc) is used as a simplified symbol for VIH.DQ(DC100)

NOTE 6: VIL(dc) is used as a simplified symbol for VIL.DQ(DC100)

NOTE 7: VIH(ac) is used as a simplified symbol for VIH.DQ(AC150), VIH.DQ(AC135) and VIH.DQ(AC150) value is used

when Vref + 0.150V is referenced, VIH.DQ(AC135) value is used when Vref + 0.135V is referenced.

NOTE 8: VIL(ac) is used as a simplified symbol for VIL.DQ(AC150), VIL.DQ(AC135) and VIL.DQ(AC150) value is used

when Vref - 0.150V is referenced, VIL.DQ(AC135) value is used when Vref - 0.135V is referenced.

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Table 15. Differential AC and DC Input Levels

Symbol Parameter Min. Max. Unit Note

VIHdiff Differential input high 0.2 Note 3 V 1

VILdiff Differential input logic low Note 3 - 0.2 V 1

VIHdiff(ac) Differential input high ac 2 x (VIH(ac) - VREF) Notes 3 V 2

VILdiff(ac) Differential input low ac Note 3 2 x (VIL(ac) - VREF) V 2

NOTE 1: Used to define a differential signal slew-rate.

NOTE 2: For CK - CK# use VIH/VIL(ac) of ADD/CMD and VREFCA; for DQSL, DQSL#, DQSU, DQSU# 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.

NOTE 3: These values are not defined; however, the single-ended signals CK, CK#, DQSL, DQSL#, DQSU, DQSU# 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.

Table 16. Capacitance (VDD = 1.5V, f = 1MHz, TOPER = 25 °C)

DDR3-1600

Symbol Parameter Unit Note

CIO Input/output capacitance,

(DQ, DM, DQS, DQS#) 1.4 2.3 pF 1, 2, 3

CCK Input capacitance, CK and CK# 0.8 1.4 pF 2, 3

CDCK Input capacitance delta,

CK and CK# 0 0.15 pF 2, 3, 4

CDDQS Input/output capacitance delta,

DQS and DQS# 0 0.15 pF 2, 3, 5

CI Input capacitance,

(CTRL, ADD, CMD input-only pins) 0.75 1.3 pF 2, 3, 6

CDI_CTRL Input capacitance delta,

(All CTRL input-only pins) -0.4 0.2 pF 2, 3, 7,

CDI_ADD_CMD Input capacitance delta,

(All ADD, CMD input-only pins) -0.4 0.4 pF 2, 3, 9,

CDIO Input/output capacitance delta,

(DQ, DM, DQS, DQS#) -0.5 0.3 pF 2, 3,

CZQ Input/output capacitance of ZQ pin - 3 pF 2, 3,

NOTE 1: Although the DM pins have different functions, the loading matches DQ and DQS.

NOTE 2: This parameter is not subject to production test. It is verified by design and characterization. VDD=VDDQ=1.5V,

VBIAS=VDD/2 and ondie termination off.

NOTE 3: This parameter applies to monolithic devices only; stacked/dual-die devices are not covered here.

NOTE 4: Absolute value of CCK-CCK#.

NOTE 5: Absolute value of CIO(DQS)-CIO(DQS#).

NOTE 6: CI applies to ODT, CS#, CKE, A0-A14, BA0-BA2, RAS#, CAS#, WE#.

NOTE 7: CDI_CTRL applies to ODT, CS# and CKE.

NOTE 8: CDI_CTRL=CI(CTRL)-0.5*(CI(CK)+CI(CK#)).

NOTE 9: CDI_ADD_CMD applies to A0-A12, BA0-BA2, RAS#, CAS# and WE#.

NOTE 10: CDI_ADD_CMD=CI(ADD_CMD) - 0.5*(CI(CK)+CI(CK#)).

NOTE 11: CDIO=CIO(DQ,DM) - 0.5*(CIO(DQS)+CIO(DQS#)).

NOTE 12: Maximum external load capacitance on ZQ pin: 5 pF.

Min. Max.

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Table 17. IDD specification parameters and test conditions (VDD = 1.5V ± 0.075V, TOPER = -40~95 °C)

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Parameter & Test Condition Symbol Max. Unit

Operating One Bank Active-Precharge Current

CKE: High; External clock: On; BL: 8*1; AL: 0; CS#: High between ACT and

PRE; Command, Address, Bank Address Inputs: partially toggling; Data IO:

MID-LEVEL; DM:stable at 0; Bank Activity: Cycling with one bank active at a

time: 0,0,1,1,2,2,...;Output Buffer and RTT: Enabled in Mode Registers*2;

ODT Signal: stable at 0.

IDD0 63 mA

Operating One Bank Active-Read-Precharge Current

CKE: High; External clock: On; BL: 8*1, 7; AL:0; CS#: High between ACT, RD

and PRE; Command, Address, Bank Address Inputs, Data IO: partially

toggling; DM:stable at 0; Bank Activity: Cycling with one bank active at a time:

0,0,1,1,2,2,...; Output Buffer and RTT: Enabled in Mode Registers*2; ODT

Signal: stable at 0.

IDD1 83 mA

Precharge Standby Current

CKE: High; External clock: On; BL: 8*1; AL: 0; CS#: stable at 1; Command,

Address, Bank Address Inputs: partially toggling; Data IO: MID-LEVEL;

DM:stable at 0; Bank Activity: all banks closed; Output Buffer and RTT:

Enabled in Mode Registers*2; ODT Signal: stable at 0.

IDD2N 30 mA

Precharge Pow er-Down Current Slow Exit

CKE: Low; External clock: On; BL: 8*1; AL: 0; CS#: stable at 1; Command,

Address, Bank Address Inputs: stable at 0; Data IO: MID-LEVEL; DM:stable

at 0; Bank Activity: all banks closed; Output Buffer and RTT: Enabled in

Mode Registers*2; ODT Signal: stable at 0; Pecharge Power Down Mode:

Slow Exit.*3

IDD2P0 18 mA

Precharge Power-Down Current Fast Exit

CKE: Low; External clock: On; BL: 8*1; AL: 0; CS#: stable at 1; Command,

Address, Bank Address Inputs: stable at 0; Data IO: MID-LEVEL; DM:stable

at 0; Bank Activity: all banks closed; Output Buffer and RTT: Enabled in

Mode Registers*2; ODT Signal: stable at 0; Pecharge Power Down Mode:

Fast Exit.*3

IDD2P1 26 mA

Precharge Quiet Standby Current

CKE: High; External clock: On; BL: 8*1; AL: 0; CS#: stable at 1; Command,

Address, Bank Address Inputs: stable at 0; Data IO: MID-LEVEL; DM:stable

at 0;Bank Activity: all banks closed; Output Buffer and RTT: Enabled in

Mode Registers*2; ODT Signal: stable at 0.

IDD2Q 30 mA

Active Standby Current

CKE: High; External clock: On; BL: 8*1; AL: 0; CS#: stable at 1; Command,

Address, Bank Address Inputs: partially toggling; Data IO: MID-LEVEL;

DM:stable at 0;Bank Activity: all banks open; Output Buffer and RTT:

Enabled in Mode Registers*2; ODT Signal: stable at 0.

IDD3N 69 mA

Active Power-Down Current

CKE: Low; External clock: On; BL: 8*1; AL: 0; CS#: stable at 1; Command,

Address, Bank Address Inputs: stable at 0; Data IO: MID-LEVEL;DM:stable

at 0; Bank Activity: all banks open; Output Buffer and RTT: Enabled in

Mode Registers*2; ODT Signal: stable at 0

IDD3P 49 mA

Operating Burst Read Current

CKE: High; External clock: On; BL: 8*1, 7; AL: 0; CS#: High between RD;

Command, Address, Bank Address Inputs: partially toggling; DM:stable at

0; Bank Activity: all banks open, RD commands cycling through banks:

0,0,1,1,2,2,...; tput Buffer and RTT: Enabled in Mode Registers*2; ODT

Signal: stable at 0.

IDD4R 208 mA

Operating Burst Write Current

CKE: High; External clock: On; BL: 8*1; AL: 0; CS#: High between WR;

Command, Address, Bank Address Inputs: partially toggling; DM: stable at

0; Bank Activity: all banks open. Output Buffer and RTT: Enabled in Mode

Registers*2; ODT Signal: stable at HIGH.

IDD4W 175 mA

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Burst Refresh Current

CKE: High; External clock: On; BL: 8*1; AL: 0; CS#: High between tREF;

Command, Address, Bank Address Inputs: partially toggling; Data IO: MID-

LEVEL;DM:stable at 0; Bank Activity: REF command every tRFC; Output

Buffer and RTT: Enabled in Mode Registers*2; ODT Signal: stable at 0.

IDD5B 185 mA

TCASE: 0 - 85°C IDD6 20 mA

Self Refresh Current:

Auto Self-Refresh (ASR): Disabled*4; Self-Refresh

Temperature Range (SRT): Normal*5; CKE: Low; External

clock: Off; CK and CK#: LOW; BL: 8*1; AL: 0; CS#,

Command, Address, Bank Address, Data IO: MID-

LEVEL;DM:stable at 0; Bank Activity: Self-Refresh

operation; Output Buffer and RTT: Enabled in Mode

Registers*2; ODT Signal: MID-LEVEL

TCASE: -40 - 95°C IDD6ET 25 mA

Operating Bank Interleave Read Current

CKE: High; External clock: On; BL: 8*1, 7; AL: CL-1; CS#: High between ACT

and RDA; Command, Address, Bank Address Inputs: partially toggling;

DM:stable at 0; Output Buffer and RTT: Enabled in Mode Registers*2; ODT

Signal: stable at 0.

IDD7 230 mA

RESET Low Current

RESET: LOW; External clock: Off; CK and CK#: LOW; CKE: FLOATING;

CS#, Command, Address,

Bank Address, Data IO: FLOATING; ODT Signal: FLOATING

RESET Low current reading is valid once power is stable and RESET has

been LOW for at least 1ms.

IDD8 19 mA

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. Pecharge 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. Read Burst Type: Nibble Sequential, set MR0 A[3] = 0B

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Table 18. Electrical Characteristics and Recommended A.C. Operating Conditions

(VDD = 1.5V ± 0.075V, TOPER = -40~95 °C)

Symbol Parameter Min. Unit

tAA Internal read command to first data 13.75 20 ns

tRCD ACT to internal read or write delay time 13.75 - ns

tRP PRE command period 13.75 - ns

tRC ACT to ACT or REF command period 48.75 - ns

tRAS ACTIVE to PRECHARGE command period 35 9 * tREFI ns

CL=7, CWL=6 1.875 <2.5 ns

CL=8, CWL=6 1.875 <2.5 ns

CL=9, CWL=7 1.5 <1.875 ns

CL=10, CWL=7 1.5 <1.875 ns

CL=11, CWL=8 1.25 <1.5 ns

tCK(avg) Average clock period

tCK (DLL_OFF) Minimum Clock Cycle Time (DLL off mode) 8-ns

tCH(avg) Average clock HIGH pulse width 0.47 0.53 tCK

tCL(avg) Average Clock LOW pulse width 0.47 0.53 tCK

tDQSQ DQS, DQS# to DQ skew, per group, per access - 100 ps

tQH DQ output hold time from DQS, DQS# 0.38 - tCK

tLZ(DQ) DQ low-impedance time from CK, CK# -450 225 ps

tHZ(DQ) DQ high impedance time from CK, CK# - 225 ps

AC150 10 - ps

tDS(base) Data setup time to DQS, DQS#

referenced to Vih(ac) / Vil(ac) levels AC135 -- ps

tDH(base) Data hold time from DQS, DQS#

referenced to Vih(dc) / Vil(dc) levels DC100 45 - ps

tDIPW DQ and DM Input pulse width for each input 360 - ps

tRPRE DQS,DQS# differential READ Preamble 0.9 - tCK

tRPST DQS, DQS# differential READ Postamble 0.3 - tCK

tQSH DQS, DQS# differential output high time 0.4 - tCK

tQSL DQS, DQS# differential output low time 0.4 - tCK

tWPRE DQS, DQS# differential WRITE Preamble 0.9 - tCK

tWPST DQS, DQS# differential WRITE Postamble 0.3 - tCK

tDQSCK DQS, DQS# rising edge output access

time from rising CK, CK# -225 225 ps

tLZ(DQS) DQS and DQS# low-impedance time

(Referenced from RL - 1) -450 225 ps

tHZ(DQS) DQS and DQS# high-impedance time

(Referenced from RL + BL/2) - 225 ps

tDQSL DQS, DQS# differential input low pulse width 0.45 0.55 tCK

tDQSH DQS, DQS# differential input high pulse width 0.45 0.55 tCK

tDQSS DQS, DQS# rising edge to CK, CK# rising edge -0.27 0.27 tCK

tDSS DQS, DQS# falling edge setup time to

CK, CK# rising edge 0.18 - tCK

tDSH DQS, DQS# falling edge hold time from

CK, CK# rising edge 0.18 - tCK

tDLLK DLL locking time 512 - tCK

tRTP Internal READ Command to

PRECHARGE Command delay

max

(4nCK,

7.5ns) -

-12

Max.

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tWTR Delay from start of internal write

transaction to internal read command

max

(4nCK,

7.5ns)

tWR WRITE recovery time 15 - ns

tMRD Mode Register Set command cycle time 4-tCK

tMOD Mode Register Set command update delay max

(12nCK,

15ns)

tCCD CAS# to CAS# command delay 4-tCK

tDAL(min) Auto precharge write recovery + prechargetime WR + tRP tCK

tMPRR Multi-Purpose Register Recovery Time 1-tCK

tRRD ACTIVE to ACTIVE command period max

(4nCK,

7.5ns)

tFAW Four activate window 40 - ns

AC175 45 - ps

AC150 170 - ps

tIS(base) Command and Address setup time to CK,

CK# referenced to Vih(ac) / Vil(ac) levels

AC135 -- ps

tIH(base) Command and Address hold time from CK,

CK# referenced to Vih(dc) / Vil(dc) levels DC100 120 - ps

tIPW Control and Address Input pulse width for

each input 560 - ps

tZQinit Power-up and RESET calibration time 512 - tCK

tZQoper Normal operation Full calibration time 256 - tCK

tZQCS Normal operation Short calibration time 64 - tCK

tXPR Exit Reset from CKE HIGH to a valid command

max

(5nCK,

tRFC+

10ns)

tXS Exit Self Refresh to commands not

requiring a locked DLL

max

(5nCK,

tRFC

+10ns)

tXSDLL Exit Self Refresh to commands requiring a

locked DLL

tDLLK

(min) - tCK

tCKESR Minimum CKE low width for Self Refresh

entry to exit timing

tCKE

(min) +

1 nCK

tCKSRE Valid Clock Requirement after Self Refresh Entry (SRE)

or Power-Down Entry (PDE)

max

(5 nCK,

10ns)

tCKSRX Valid Clock Requirement before Self Refresh Exit (SRX)

or Power-Down Exit (PDX) or Reset Exit

max

(5 nCK,

10ns)

tXP Exit Power Down with DLL on to any valid command;

Exit Precharge Power Down with DLL frozen to

commands not requiring a locked DLL

max

(3 nCK,

6ns)

tXPDLL Exit Precharge Power Down with DLL

frozen to commands requiring a lockedDLL

max

(10nCK,

24ns)

tCKE CKE minimum pulse width max

(3 nCK,

5ns)

tCPDED Command pass disable delay 1-tCK

tPD Power Down Entry to Exit Timing tCKE

(min)

9 *

tREFI

tACTPDEN Timing of ACT command to Power Down entry 1-tCK

tPRPDEN Timing of PRE or PREA command to

Power Down entry 1-tCK

tRDPDEN Timing of RD/RDA command to Power Down entry RL + 4 +

1 - tCK

tWRPDEN Timing of WR command to Power Down

entry (BL8OTF, BL8MRS, BC4OTF)

WL + 4

(tWR / tCK)

- tCK

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tWRAPDEN Timing of WRA command to Power

Down entry (BL8OTF, BL8MRS,BC4OTF)

WL + 4

WR + 1

- tCK

tWRPDEN Timing of WR command to Power Down entry

(BC4MRS)

WL + 2

(tWR / tCK)

- tCK

tWRAPDEN Timing of WRA command to Power Down entry

(BC4MRS)

WL + 2

WR + 1

- tCK

tREFPDEN Timing of REF command to Power Down entry 1-tCK

tMRSPDEN Timing of MRS command to Power Down entry tMOD

(min) -

ODTLon ODT turn on Latency WL - 2 = CWL + AL - 2

ODTLoff ODT turn off Latency WL - 2 = CWL + AL - 2 tCK

ODTH4

ODT high time without write command or

with write command and BC4 4-tCK

ODTH8 ODT high time with Write command and BL8 6-tCK

tAONPD Asynchronous RTT turn-on delay

(Power- Down with DLL frozen) 2 8.5 ns

tAOFPD Asynchronous RTT turn-off delay

(Power-Down with DLL frozen) 2 8.5 ns

tAON RTT turn-on -225 225 ps

tAOF RTT_Nom and RTT_WR turn-off time

from ODTLoff reference 0.3 0.7 tCK

tADC RTT dynamic change skew 0.3 0.7 tCK

tWLMRD First DQS/DQS# rising edge after write

leveling mode is programmed 40 - tCK

tWLDQSEN DQS/DQS# delay after write leveling

mode is programmed 25 - tCK

tWLS Write leveling setup time from rising CK,

CK# crossing to rising DQS, DQS# crossing 165 - ps

tWLH Write leveling hold time from rising DQS,

DQS# crossing to rising CK, CK# crossing 165 - ps

tWLO Write leveling output delay 0 7.5 ns

tWLOE Write leveling output error 0 2 ns

tRFC REF command to ACT or REF command time 260 - ns

-40°C to 85°C - 7.8 µs

tREFI Average periodic refresh interval 85°C to 95°C - 3.9 µs

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- Multi-Purpose Register (MPR)

The Multi Purpose Register (MPR) function is used to Read out a predefined system timing calibration bit sequence.

Figure 8. MPR Block Diagram

Memory Core

(all banks precharged)

MRS 3

【A2】

DQ, DM, DQS, DQS#

Multipurpose register

Pre-defined data for Reads

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. The

resulting operation, when a RD or RDA command is issued, is defined by MR3 bits A[1:0] when the MPR is enabled

as shown in table 20. 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). Note that in MPR mode RDA has the same

functionality as a READ command which means the auto precharge part of RDA is ignored. 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.

Table 19. MPR MR3 Register Definition

MR3 A[2] MR3 A[1:0] Function

MPR MPR-Loc

0b Don’t care (0b or 1b)

Normal operation, no MPR transaction.

All subsequent Reads will come from DRAM array.

All subsequent Write will go to DRAM array.

1b See the table 20 Enable MPR mode, subsequent RD/RDA commands defined by

MR3 A[1:0].

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- MPR Functional Description

• One bit wide logical interface via all DQ pins during READ operation.

• Register Read on x16:

• DQL[0] and DQU[0] drive information from MPR.

• DQL[7:1] and DQU[7:1] either drive the same information as DQL [0], or they drive 0b.

• Addressing during for Multi Purpose Register reads for all MPR agents:

• BA [2:0]: don’t care

• A[1:0]: A[1:0] must be equal to ‘00’b. Data read burst order in nibble is fixed

• A[2]: For BL=8, A[2] must be equal to 0b, burst order is fixed to [0,1,2,3,4,5,6,7], *) For Burst Chop 4 cases, the

burst order is switched on nibble base A [2]=0b, Burst order: 0,1,2,3 *) A[2]=1b, Burst order: 4,5,6,7 *)

• A[9:3]: don’t care

• A10/AP: don’t care

• A12/BC: Selects burst chop mode on-the-fly, if enabled within MR0.

• A11, A13, ... (if available): don’t care

•Regular interface functionality during register reads:

• Support two Burst Ordering which are switched with A2 and A[1:0]=00b.

• Support of read burst chop (MRS and on-the-fly via A12/BC)

• All other address bits (remaining column address bits including A10, all bank address bits) will be ignored by the

DDR3 SDRAM.

• Regular read latencies and AC timings apply.

• DLL must be locked prior to MPR Reads.

NOTE: *) Burst order bit 0 is assigned to LSB and burst order bit 7 is assigned to MSB of the selected MPR agent.

Table 20. MPR MR3 Register Definition

MR3

A[2] MR3

A[1:0] Function Burst Length Read Address

A[2:0] Burst Order and Data Pattern

BL8 000b Burst order 0, 1, 2, 3, 4, 5, 6, 7

Pre-defined Data Pattern

[0, 1, 0, 1, 0, 1, 0, 1]

BC4 000b Burst order 0, 1, 2, 3

Pre-defined Data Pattern

[0, 1, 0, 1]

1b 00b

Read Predefined

Pattern for

System

Calibration BC4 100b Burst order 4, 5, 6, 7

Pre-defined Data Pattern

[0, 1, 0, 1]

BL8 000b Burst order 0, 1, 2, 3, 4, 5, 6, 7

BC4 000b Burst order 0, 1, 2, 3

1b 01b RFU

BC4 100b Burst order 4, 5, 6, 7

BL8 000b Burst order 0, 1, 2, 3, 4, 5, 6, 7

BC4 000b Burst order 0, 1, 2, 3

1b 10b RFU

BC4 100b Burst order 4, 5, 6, 7

BL8 000b Burst order 0, 1, 2, 3, 4, 5, 6, 7

BC4 000b Burst order 0, 1, 2, 3

1b 11b RFU

BC4 100b Burst order 4, 5, 6, 7

zNo Operation (NOP) Command

The No operation (NOP) command is used to instruct the selected DDR3 SDRAM to perform a NOP (CS# low and

RAS#, CAS# and WE# high). This prevents unwanted commands from being registered during idle or wait states.

Operations already in progress are not affected.

zDeselect Command

The Deselect function (CS# HIGH) prevents new commands from being executed by the DDR3 SDRAM. The DDR3

SDRAM is effectively deselected. Operations already in progress are not affected.

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zDLL- Off Mode

DDR3 DLL-off mode is entered by setting MR1 bit A0 to “1”; this will disable the DLL for subsequent operations until

A0 bit set back to “0”. The MR1 A0 bit for DLL control can be switched either during initialization or later.

The DLL-off Mode operations listed below are an optional feature for DDR3. The maximum clock frequency for DLL-

off Mode is specified by the parameter tCKDLL_OFF. There is no minimum frequency limit besides the need to

satisfy the refresh interval, tREFI.

Due to latency counter and timing restrictions, only one value of CAS Latency (CL) in MR0 and CAS Write Latency

(CWL) in MR2 are supported. The DLL-off mode is only required to support setting of both CL=6 and CWL=6.

DLL-off mode will affect the Read data Clock to Data Strobe relationship (tDQSCK) but not the data Strobe to Data

relationship (tDQSQ, tQH). Special attention is needed to line up Read data to controller time domain. Comparing

with DLL-on mode, where tDQSCK starts from the rising clock edge (AL+CL) cycles after the Read command, the

DLL-off mode tDQSCK starts (AL+CL-1) cycles after the read command. Another difference is that tDQSCK may

not be small compared to tCK (it might even be larger than tCK) and the difference between tDQSCKmin and

tDQSCKmax is significantly larger than in DLL-on mode.

The timing relations on DLL-off mode READ operation have shown at the following Timing Diagram (CL=6, BL=8)

Figure 9. DLL-off mode READ Timing Operation

CK#

T1 T2 T3 T4 T5 T6 T7 T8 T9T0

ADDRESS

T10

COMMAND

DQS#

DQS

Don't Care

NOPREAD NOP NOP NOP NOP NOP NOP NOP NOP NOP

Bank,

Col b

RL (DLL_on) = AL + CL = 6 (CL = 6, AL = 0)

CL = 6

Din

b+1

Din

b+2

Din

b+3

Din

b+4

Din

b+5

Din

b+6

Din

b+7

Din

b+1

Din

b+2

Din

b+3

Din

b+4

Din

b+5

Din

b+6

Din

b+7

DQS#

DQS

Din

b+1

Din

b+2

Din

b+3

Din

b+4

Din

b+5

Din

b+6

Din

b+7

DQS#

DQS

(DLL_on)

(DLL_off)

RL (DLL_off) = AL + (CL-1) = 5 tDQSCK(DLL_off)_min

tDQSCK(DLL_off)_max

NOTE 1. The tDQSCK is used here for DQS, DQS# and DQ to have a simplified diagram; the DLL_off shif t will affect

both timings in the same way and the skew between all DQ and DQS, DQS# signals will stil l be tDQSQ.

TRANSITIONING DATA

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zDLL on/off switching procedure

DDR3 DLL-off mode is entered by setting MR1 bit A0 to “1”; this will disable the DLL for subsequent operation until

A0 bit set back to “0”.

zDLL “on” to DLL “off” Procedure

To switch from DLL “on” to DLL “off” requires the frequency to be changed during Self-Refresh outlined in the

following procedure:

1. Starting from Idle state (all banks pre-charged, all timing fulfilled, and DRAMs On-die Termination resistors,

RTT, must be in high impedance state before MRS to MR1 to disable the DLL).

2. Set MR1 Bit A0 to “1” to disable the DLL.

3. Wait tMOD.

4. Enter Self Refresh Mode; wait until (tCKSRE) satisfied.

5.Change frequency, in guidance with “Input Clock Frequency Change” section.

6. Wait until a stable clock is available for at least (tCKSRX) at DRAM inputs.

7. Starting with the Self Refresh Exit command, CKE must continuously be registered HIGH until all tMOD

timings from any MRS command are satisfied. In addition, if any ODT features were enabled in the mode

registers when Self Refresh mode was entered, the ODT signal must continuously be registered LOW until all

tMOD timings from any MRS command are satisfied. If both ODT features were disabled in the mode

registers when Self Refresh mode was entered, ODT signal can be registered LOW or HIGH.

8. Wait tXS, and then set Mode Registers with appropriate values (especially an update of CL, CWL, and WR

may be necessary. A ZQCL command may also be issued after tXS).

9. Wait for tMOD, and then DRAM is ready for next command.

Figure 10. DLL Switch Sequence from DLL-on to DLL-off

T1 Ta0 Ta1 Tb0 Tc0 Td0 Td1 Te0 Te1T0 Tf0

tMOD

Notes 1

Don't CareTIME BREAK

NOPMRS SRE NOP SRX NOP MRS NOP

VALID

tCKSRE

Notes 2 Notes 3 Notes 6 Notes 7

Notes 8

Notes 4 tCKSRX

Notes 5

tXS tMOD

tCKESR

VALID

Notes 8

NOTES:

1. Starting wit h Idle State, RTT in Hi-Z state

2. Disable DLL by setting MR1 Bit A0 to 1

3. Enter SR

4. Change Frequency

5. Clock must be stable tCKSRX

6. Exit SR

7. Update Mode registers with DLL off parameters setting

8. Any valid command

ODT: Static LOW in case RTT_Nom and RTT_WR is enabled, otherwise static Low or High

CK#

COMMAND

CKE

ODT

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zDLL “off” to DLL “on” Procedure

To switch from DLL “off” to DLL “on” (with requires frequency change) during Self-Refresh:

1. Starting from Idle state (all banks pre-charged, all timings fulfilled and DRAMs On-die Termination resistors

(RTT) must be in high impedance state before Self-Refresh mode is entered).

2.Enter Self Refresh Mode, wait until tCKSRE satisfied.

3. Change frequency, in guidance with “Input clock frequency change” section.

4.Wait until a stable clock is available for at least (tCKSRX) at DRAM inputs.

5. Starting with the Self Refresh Exit command, CKE must continuously be registered HIGH until tDLLK timing

from subsequent DLL Reset command is satisfied. In addition, if any ODT features were enabled in the mode

registers when Self Refresh mode was entered, the ODT signal must continuously be registered LOW until

tDLLK timings from subsequent DLL Reset command is satisfied. If both ODT features are disabled in the

mode registers when Self Refresh mode was entered, ODT signal can be registered LOW or HIGH.

6.Wait tXS, then set MR1 Bit A0 to “0” to enable the DLL.

7. Wait tMRD, then set MR0 Bit A8 to “1” to start DLL Reset.

8. Wait tMRD, then set Mode registers with appropriate values (especially an update of CL, CWL, and WR may

be necessary. After tMOD satisfied from any proceeding MRS command, a ZQCL command may also be

issued during or after tDLLK).

9.Wait for tMOD, then DRAM is ready for next command (remember to wait tDLLK after DLL Reset before

applying command requiring a locked DLL!). In addition, wait also for tZQoper in case a ZQCL command was

issued.

Figure11. DLL Switch Sequence from DLL-off to DLL on

CK#

Ta0 Ta1 Tb0 Tc0 Tc1 Td0 Te0 Tf1 Tg0T0

Th0

COMMAND

CKE

ODT

Notes 1

Don't CareTIME BREAK

SRENOP NOP SRX MRS MRS MRS

VALID

tCKSRE

Notes 2 Notes 5 Notes 7

Notes 3 tCKSRX

Notes 4

tXS tMRD

tCKESR

NOTES:

1. Startin g wit h Id le St a te

2. Enter SR

3. Change Frequency

4. Clock must be stable tCKSRX

5. Exit SR

6. Set DLL on by M R 1 A0 = 0

7. Start DLL Reset by MR0 A8=1

8. Update Mode registers

9. Any valid command

ODT: Static LOW in case RTT_Nom and RTT_WR is enabled, otherwise static Low or High

Notes 6 Notes 8

tDLLK

ODTLoff + 1 * tCK tMRD

Notes 9

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zJitter Notes

NOTE 1. Unit ‘tCK(avg)’ represents the actual tCK(avg) of the input clock under operation. Unit ‘nCK’

represents one clock cycle of the input clock, counting the actual clock edges.ex) tMRD = 4 [nCK]

means; if one Mode Register Set command is registered at Tm, another Mode Register Set command

may be registered at Tm+4, even if (Tm+4 - Tm) is 4 x tCK(avg) + tERR(4per),min.

NOTE 2. These parameters are measured from a command/address signal (CKE, CS#, RAS#, CAS#, WE#,

ODT, BA0, A0, A1, etc.) transition edge to its respective clock signal (CK/CK#) crossing. The spec

values are not affected by the amount of clock jitter applied (i.e. tJIT(per), tJIT(cc), etc.), as the setup

and hold are relative to the clock signal crossing that latches the command/address. That is, these

parameters should be met whether clock jitter is present or not.

NOTE 3. These parameters are measured from a data strobe signal (DQS(L/U), DQS(L/U)#) crossing to its

respective clock signal (CK, CK#) crossing. The spec values are not affected by the amount of clock

jitter applied (i.e. tJIT(per), tJIT(cc), etc.), as these are relative to the clock signal crossing. That is,

these parameters should be met whether clock jitter is present or not.

NOTE 4. These parameters are measured from a data signal (DM(L/U), DQ(L/U)0, DQ(L/U)1, etc.) transition

edge to its respective data strobe signal (DQS(L/U), DQS(L/U)#) crossing.

NOTE 5. For these parameters, the DDR3 SDRAM device supports tnPARAM [nCK] = RU{ tPARAM [ns] /

tCK(avg) [ns] }, which is in clock cycles, assuming all input clock jitter specifications are satisfied.

NOTE 6. When the device is operated with input clock jitter, this parameter needs to be derated by the actual

tERR(mper),act of the input clock, where 2 <= m <= 12. (output deratings are relative to the SDRAM

input clock.)

NOTE 7. When the device is operated with input clock jitter, this parameter needs to be derated by the actual

tJIT(per),act of the input clock. (output deratings are relative to the SDRAM input clock.)

Table 21. Input clock jitter spec parameter -12

Parameter Symbol Unit

Clock period jitter tJIT (per) -70 70 ps

Clock period jitter during DLL locking period tJIT (per,lck) -60 60 ps

Cycle to cycle clock period jitter tJIT (cc) 140 ps

Cycle to cycle clock period jitter during DLL locking

period tJIT (cc,lck) 120 ps

Cumulative error across 2 cycles tERR (2per) -103 103 ps

Cumulative error across 3 cycles tERR (3per) -122 122 ps

Cumulative error across 4 cycles tERR (4per) -136 136 ps

Cumulative error across 5 cycles tERR (5per) -147 147 ps

Cumulative error across 6 cycles tERR (6per) -155 155 ps

Cumulative error across 7 cycles tERR (7per) -163 163 ps

Cumulative error across 8 cycles tERR (8per) -169 169 ps

Cumulative error across 9 cycles tERR (9per) -175 175 ps

Cumulative error across 10 cycles tERR (10per) -180 180 ps

Cumulative error across 11 cycles tERR (11per) -184 184 ps

Cumulative error across 12 cycles tERR (12per) -188 188 ps

Cumulative error across n cycles, n=13...50, inclusive tERR (nper) tERR (nper)min = (1+0.68ln(n)) * tJIT (per)min

tERR (nper)max = (1+0.68ln(n)) * tJIT (per)max

Min. Max.

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zInput Clock frequency change

Once the DDR3 SDRAM is initialized, the DDR3 SDRAM requires the clock to be “stable” during almost all states of

normal operation. This means once the clock frequency has been set and is to be in the “stable state”, the clock

period is not allowed to deviate except for what is allowed for by the clock jitter and SSC (spread spectrum clocking)

specification.

The input clock frequency can be changed from one stable clock rate to another stable clock rate under two

conditions: (1) Self-Refresh mode and (2) Precharge Power-Down mode. Outside of these two modes, it is illegal to

change the clock frequency.

For the first condition, once the DDR3 SDRAM has been successfully placed in to Self-Refresh mode and tCKSRE

has been satisfied, the state of the clock becomes a don’t care. Once a don’t care, changing the clock frequency is

permissible, provided the new clock frequency is stable prior to tCKSRX. When entering and exiting Self-Refresh

mode of the sole purpose of changing the clock frequency, the Self-Refresh entry and exit specifications must still

be met. The DDR3 SDRAM input clock frequency is allowed to change only within the minimum and maximum

operating frequency specified for the particular speed grade.

The second condition is when the DDR3 SDRAM is in Precharge Power-Down mode (either fast exit mode or slow

exit mode). If the RTT_Nom feature was enabled in the mode register prior to entering Precharge power down

mode, the ODT signal must continuously be registered LOW ensuring RTT is in an off state. If the RTT_Nom

feature was disabled in the mode register prior to entering Precharge power down mode, RTT will remain in the off

state. The ODT signal can be registered either LOW or HIGH in this case. A minimum of tCKSRE must occur after

CKE goes LOW before the clock frequency may change. The DDR3 SDRAM input clock frequency is allowed to

change only within the minimum and maximum operating frequency specified for the particular speed grade. During

the input clock frequency change, ODT and CKE must be held at stable LOW levels. Once the input clock

frequency is changed, stable new clocks must be provided to the DRAM tCKSRX before precharge Power Down

may be exited; after Precharge Power Down is exited and tXP has expired, the DLL must be RESET via MRS.

Depending on the new clock frequency additional MRS commands may need to be issued to appropriately set the

WR, CL, and CWL with CKE continuously registered high. During DLL re-lock period, ODT must remain LOW and

CKE must remain HIGH. After the DLL lock time, the DRAM is ready to operate with new clock frequency.

Figure 12. Change Frequency during Precharge Power-down

CK#

T1 T2 Ta0 Tb0 Tc0 Tc1 Td0 Td1 Te0T0

ADDRESS

Te1

COMMAND

ODT

NOPNOP NOP NOP NOP MRS NOP VALID

DLL

RESET

High-Z

High-z

DQS#

DQS

NOTES

1. Applicable for both SLOW EXIT and FAST EXIT Precharge Power-down.

2. tAOFPD and tAOF must be statisfied and outputs High-Z prior to T1;refer to ODT timing section for exact requirements

3. If the RTT_NOM feature was enable d in the mode registe r prior to entering Precharge power down mode, the ODT

signal must continuously be registered LOW ensuring RTT is in an off state, as shown in Figure 13. If the RTT_NOM feature was disabled in the mode

register prior to entering Prechar ge power down mode, RTT will remain in the off state. The ODT signal can be registered either LOW or HIGH in this case.

tCH tCL

tCK

tCKSRE tCHb tCLb

tCKb

tCHb tCLb

tCKb

tCHb tCLb

tCKb

tCKSRX

tCKE

CKE

tIH tIS

VALID

tXP

Enter PRECHARGE

Power-Down Mode

tCPDED

PREVIOUS CLOCK FREQUENCY NEW CLOCK FREQUENCY

tAOFPD / tAOF

Frequency Change Exit PRECHARGE

Power-Down Mode

tDLLK

Don't Care

Indicates a break

in time scale

tIH

tIS

tIH

tIS

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zWrite Leveling

For better signal integrity, DDR3 memory adopted fly by topology for the commands, addresses, control signals,

and clocks. The fly by topology has benefits from reducing number of stubs and their length but in other aspect,

causes flight time skew between clock and strobe at every DRAM on DIMM. It makes it difficult for the Controller to

maintain tDQSS, tDSS, and tDSH specification. Therefore, the controller should support “write leveling” in DDR3

SDRAM to compensate the skew.

The memory controller can use the “write leveling” feature and feedback from the DDR3 SDRAM to adjust the

DQS – DQS# to CK – CK# relationship. The memory controller involved in the leveling must have adjustable delay

setting on DQS – DQS# to align the rising edge of DQS – DQS# with that of the clock at the DRAM pin. DRAM

asynchronously feeds back CK – CK#, sampled with the rising edge of DQS – DQS#, through the DQ bus. The

controller repeatedly delays DQS – DQS# until a transition from 0 to 1 is detected. The DQS – DQS# delay

established though this exercise would ensure tDQSS specification.

Besides tDQSS, tDSS, and tDSH specification also needs to be fulfilled. One way to achieve this is to combine the

actual tDQSS in the application with an appropriate duty cycle and jitter on the DQS- DQS# signals. Depending on

the actual tDQSS in the application, the actual values for tDQSL and tDQSH may have to be better than the

absolute limits provided in “AC Timing Parameters” section in order to satisfy tDSS and tDSH specification.

DQS/DQS# driven by the controller during leveling mode must be determined by the DRAM based on ranks

populated. Similarly, the DQ bus driven by the DRAM must also be terminated at the controller.

One or more data bits should carry the leveling feedback to the controller across the DRAM configurations X16. On

a X16 device, both byte lanes should be leveled independently. Therefore, a separate feedback mechanism should

be available for each byte lane. The upper data bits should provide the feedback of the upper diff_DQS (diff_UDQS)

to clock relationship whereas the lower data bits would indicate the lower diff_DQS (diff_LDQS) to clock relationship.

Figure 13. Write Leveling Concept

CK#

T1 T2 T3 T4 T5 T6 T7T0

Diff_DQS

Source

Destination

T0 T1 T2 T3 T4 T5 T6Tn

CK#

Diff_DQS

0 0

Diff_DQS

1 1

Push DQS to capture

0-1 transition

0 or 1

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zDRAM setting for write leveling and DRAM termination function in that mode

DRAM enters into Write leveling mode if A7 in MR1 set “High” and after finishing leveling, DRAM exits from write

leveling mode if A7 in MR1 set “Low”. Note that in write leveling mode, only DQS/DQS# terminations are activated

and deactivated via ODT pin not like normal operation.

Table 22. DRAM termination function in the leveling mode

ODT pin at DRAM DQS, DQS# termination DQs termination

De-asserted off off

Asserted on off

Note 1: In write leveling mode with its output buffer disabled (MR1[bit7]=1 with MR1[bit12]=1) all RTT_Nom settings are

allowed; in Write Leveling Mode with its output buffer enabled (MR1[bit7]=1 with MR1[bit12]=0) only RTT_Nom

settings of RZQ/2, RZQ/4, and RZQ/6 are allowed.

zProcedure Description

Memory controller initiates Leveling mode of all DRAMs by setting bit 7 of MR1 to 1. With entering write leveling

mode, the DQ pins are in undefined driving mode. During write leveling mode, only NOP or Deselect commands are

allowed. As well as an MRS command to exit write leveling mode. Since the controller levels one rank at a time, the

output of other rank must be disabled by setting MR1 bit A12 to 1. Controller may assert ODT after tMOD, time at

which DRAM is ready to accept the ODT signal.

Controller may drive DQS low and DQS# high after a delay of tWLDQSEN, at which time DRAM has applied on-die

termination on these signals. After tDQSL and tWLMRD controller provides a single DQS, DQS# edge which is

used by the DRAM to sample CK – CK# driven from controller. tWLMRD(max) timing is controller dependent.

DRAM samples CK – CK# status with rising edge of DQS and provides feedback on all the DQ bits asynchronously

after tWLO timing. There is a DQ output uncertainty of tWLOE defined to allow mismatch on DQ bits; there are no

read strobes (DQS/DQS) needed for these DQs. Controller samples incoming DQ and decides to increment or

decrement DQS – DQS# delay setting and launches the next DQS/DQS# pulse after some time, which is controller

dependent. Once a 0 to 1 transition is detected, the controller locks DQS – DQS# delay setting and write leveling is

achieved for the device.

Figure14. Timing details of Write Leveling sequence

(DQS – DQS# is capturing CK – CK# low at T1 and CK – CK# high at T2)

tWLMRD

Don't CareTIME BREAK

NOPMRS NOP NOP NOP NOP NOP NOP NOP NOP NOP

tWLS

tWLH

tWLS tWLH

NOP

Notes 1 Notes 2

tWLDQSEN

tDQSL

Notes 6 tDQSH

Notes 6

tDQSL

Notes 6 tDQSH

Notes 6

CK#

COMMAND

ODT

Diff_DQS

Prime DQ

Notes 5

Notes 4

One Prime DQ:

Notes 3

Late Prime DQs

Early Prime DQs

All DQs are Prime:

Notes 3

Late Remaining DQs

Early Remaining DQs

tWLO

tWLOE

tWLO

tWLOE

tWLO

tMOD

tWLO

tWLMRD

tWLO

tWLOE

UNDEFINED Driving MODE

NOTES

1. MRS: Load MR1 to enter write leveling mode.

2. NOP: NOP or Deselect.

3. DRAM has the option to drive leveling feedback on a prime DQ or all DQs. If feedback is driven only on one DQ, the remaining DQs must be driven low, as shown in above Figure,

and maintained at this state t hrough out the leveling procedure.

4. diff_DQS is the differential data strobe (DQS, DQS#). Timing reference points are the zero crossings. DQS is shown with solid line, DQS# is shown with dotted line.

5. CK, CK# : CK is shown with solid dark line, where as CK# is drawn with dotted line.

6. DQS, DQS# needs to fulfill minimum pulse width requirements tDQSH(min) and tDQSL(min) as defined for regular Writes; the max pulse w idth is system dependent.

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zWrite Leveling Mode Exit

The following sequence describes how Write Leveling Mode should be exited:

1. After the last rising strobe edge (see ~T0), stop driving the strobe signals (see ~Tc0). Note: From now on, DQ

pins are in undefined driving mode, and will remain undefined, until tMOD after the respective MR command

(Te1).

2. Drive ODT pin low (tIS must be satisfied) and keep it low (see Tb0).

3. After the RTT is switched off, disable Write Level Mode via MRS command (see Tc2).

4. After tMOD is satisfied (Te1), any valid command may be registered. (MR commands may be issued after

tMRD (Td1).

Figure 15. Timing details of Write Leveling exit

Don't CareTIME BREAK

NOPNOP NOP NOP NOP NOP NOP MRS NOP VALID NOP VALID

tWLO

tAOFmin

UNDEFINED Driving MODE

T1 T2 Ta0 Tb0 Tc0 Tc1 Tc2

T0 Td0 Td1 Te0 Te1

NOTES:

1. The DQ result = 1 between Ta0 and Tc0 is a result of the DQS, DQS# signals capturing CK high just after the T0 state.

MR1 VALID VALID

tMRD

RTT_NOM

Result = 1

TRANSITIONING

tAOFmax

tIS

ODTLoff

tMOD

CK#

COMMAND

ADDRESS

ODT

RTT_DQS_DQS#

DQS_DQS#

RTT_DQ

Notes 1

zExtended Temperature Usage

Users should refer to the DRAM supplier data sheet and/or the DIMM SPD to determine if DDR3

SDRAM devices support the following options or requirements referred to in this material:

1. Auto Self-refresh supported

2. Extended Temperature Range supported

3. Double refresh required for operation in the Extended Temperature Range (applies only for devices

supporting the Extended Temperature Range)

zAuto Self-Refresh mode - ASR mode

DDR3 SDRAM provides an Auto-Refresh mode (ASR) for application ease. ASR mode is enabled by setting MR2

bit A6=1 and MR2 bit A7=0. The DRAM will manage Self-Refresh entry in either the Normal or Extended

Temperature Ranges. In this mode, the DRAM will also manage Self-Refresh power consumption when the DRAM

operating temperature changes, lower at low temperatures and higher at high temperatures. If the ASR option is not

supported by DRAM, MR2 bit A6 must set to 0. If the ASR option is not enabled (MR2 bit A6=0), the SRT bit (MR2

bit A7) must be manually programmed with the operating temperature range required during Self-Refresh operation.

Support of the ASR option does not automatically imply support of the Extended Temperature Range.

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zSelf-Refresh Temperature Range - SRT

SRT applies to devices supporting Extended Temperature Range only. If ASR=0, the Self-Refresh Temperature

(SRT) Range bit must be programmed to guarantee proper self-refresh operation. If SRT=0, then the DRAM will set

an appropriate refresh rate for Self-Refresh operation in the Normal Temperature Range. If SRT=1, then the DRAM

will set an appropriate, potentially different, refresh rate to allow Self-Refresh operation in either the Normal or

Extended Temperature Ranges. The value of the SRT bit can effect self-refresh power consumption, please refer to

IDD table for details.

Table 23. Self-Refresh mode summary

MR2

A[6] MR2

A[7] Self-Refresh operation Allowed Operating

Temperature Range

for Self-Refresh mode

0 0

Self-Refresh rate appropriate for the Normal Temperature Range Normal (0 ~ 85°C)

0 1

Self-Refresh appropriate for either the Normal or Extended Temperature

Ranges.The DRAM must support Extended Temperature Range. The

value of the SRT bit can effect self-refresh power consumption, please

refer to the IDD table for details.

Normal and Extended

(0 ~ 95°C)

1 0

ASR enabled (for devices supporting ASR and Normal Temperature

Range).Self-Refresh power consumption is temperature dependent. Normal (0 ~ 85°C)

1 0

ASR enabled (for devices supporting ASR and Extended Temperature

Range).Self-Refresh power consumption is temperature dependent.

Normal and Extended

(0 ~ 95°C)

1 1

Illegal

zACTIVE Command

The ACTIVE command is used to open (or activate) a row in a particular bank for subsequent access. The value on

the BA0-BA2 inputs selects the bank, and the addresses provided on inputs A0-A14 selects the row. These rows

remain active (or open) for accesses until a precharge command is issued to that bank. A PRECHARGE command

must be issued before opening a different row in the same bank.

zPRECHARGE Command

The PRECHARGE command is used to deactivate the open row in a particular bank or the open row in all banks.

The bank(s) will be available for a subsequent row activation a specified time (tRP) after the PRECHARGE

command is issued, except in the case of concurrent auto precharge, where a READ or WRITE command to a

different bank is allowed as long as it does not interrupt the data transfer in the current bank and does not violate

any other timing parameters. Once a bank has been precharged, it is in the idle state and must be activated prior to

any READ or WRITE commands being issued to that bank. A PRECHARGE command is allowed if there is no

open row in that bank (idle bank) or if the previously open row is already in the process of precharging. However,

the precharge period will be determined by the last PRECHARGE command issued to the bank.

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READ Operation

zRead Burst Operation

During a READ or WRITE command DDR3 will support BC4 and BL8 on the fly using address A12 during the

READ or WRITE (AUTO PRECHARGE can be enabled or disabled).

A12=0, BC4 (BC4 = burst chop, tCCD=4)

A12=1, BL8

A12 will be used only for burst length control, not a column address.

Figure 16. READ Burst Operation RL=5 (AL=0, CL=5, BL=8)

Don't Care

NOPREAD NOP NOP NOP NOP NOP NOP NOP NOP NOP

NOTES:

1. BL8, RL = 5, AL = 0, CL = 5.

2. Dout n = data-out from column n.

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. BL8 setting activated by either MR0[A1:0 = 00] or MR0[A1:0 = 01] and A12 = 1 during READ command at T0.

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10

Bank,

Col n

TRANSITIONING DATA

tRPRE tRPST

Dout

n+1

Dout

n+2

Dout

n+3

Dout

n+4

Dout

n+5

Dout

n+6

Dout

n+7

RL = AL + CL

CL = 5

CK#

DQS, DQS#

Notes 3

Notes 2

ADDRESS

Notes 4

COMMAND

Figure 17. READ Burst Operation RL=9 (AL=4, CL=5, BL=8)

Don't Care

NOPREAD NOP NOP NOP NOP NOP NOP NOP NOP NOP

NOTES:

1. BL8, RL = 9, AL = (CL-1), CL = 5.

2. Dout n = data-out from column n.

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. BL8 setting activated by either MR0[A1:0 = 00] or MR0[A1:0 = 01] and A12 = 1 during READ command at T0.

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10

Bank,

Col n

TRANSITIONING DATA

tRPRE

Dout

n+1

Dout

n+2

RL = AL + CL

AL = 4 CL = 5

CK#

DQS, DQS#

Notes 3

Notes 2

ADDRESS

Notes 4

COMMAND

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zREAD Timing Definitions

Read timing is shown in the following figure and is applied when the DLL is enabled and locked.

Rising data strobe edge parameters:

tDQSCK min/max describes the allowed range for a rising data strobe edge relative to CK, CK#. tDQSCK is the

actual position of a rising strobe edge relative to CK, CK#. tQSH describes the DQS, DQS# differential output

high time. tDQSQ describes the latest valid transition of the associated DQ pins. tQH describes the earliest

invalid transition of the associated DQ pins.

Falling data strobe edge parameters:

tQSL describes the DQS, DQS# differential output low time. tDQSQ describes the latest valid transition of the

associated DQ pins. tQH describes the earliest invalid transition of the associated DQ pins.

tDQSQ; both rising/falling edges of DQS, no tAC defined.

Figure 18. READ timing Definition

tDQSCK

tDQSCK,min

CK#

tDQSCK,max tDQSCK,max

Rising Strobe

Region

tDQSCK,min

DQS#

DQS

tDQSCK

tQSH tQSL

Rising Strobe

Region

Associated

DQ Pins

tQH tQH

tDQSQ tDQSQ

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zRead Timing; Clock to Data Strobe relationship

Clock to Data Strobe relationship is shown in the following figure and is applied when the DLL is enabled and

locked.

Rising data strobe edge parameters:

tDQSCK min/max describes the allowed range for a rising data strobe edge relative to CK and CK#. tDQSCK

is the actual position of a rising strobe edge relative to CK and CK#. tQSH describes the data strobe high

pulse width.

Falling data strobe edge parameters:

tQSL describes the data strobe low pulse width.

Figure 19. Clock to Data Strobe relationship

NOTES:

1. Within a burst, rising strobe edge is not necessarily fixed to be always at tDQSCK(min) or tDQSCK(max). Instead, rising strobe

edge can vary between tDQSCK(min) and tDQSCK(max).

2. Notwithstanding note 1, a rising strobe edge with tDQSCK(max) at T(n) can not be immediately followed by a rising strobe edge

with tDQSCK(min) at T(n+1). This is because other timing relationships (tQSH, tQSL) exist: if tDQSCK(n+1) < 0: tDQSCK(n) < 1.0 tCK -

(tQSHmin + tQSLmin) - | tDQSCK(n+1) |

3. The DQS, DQS# differential output high time is defined by tQSH and the DQS, DQS# differential output low time is defined by tQSL.

4. Likewise, tLZ(DQS)min and tHZ(DQS)min are not tied to tDQSCKmin (early strobe case) and tLZ(DQS)max and tHZ(DQS)max are

not tied to tDQSCKmax (late strobe case).

5. The minimum pulse width of read preamble is defined by tRPRE(min).

6. The maximum read postamble is bound by tDQSCK(min) plus tQSH(min) on the left side and tHZDSQ(max) on the right side.

7. The minimum pulse width of read postamble is defined by tRPST(min).

8. The maximum read preamble is bound by tLZDQS(min) on the left side and tDQSCK(max) on the right side.

CLK#

CLK

tLZ(DQS) min

DQS, DQS#

Late Strobe

DQS, DQS#

Early Strobe tRPRE

tLZ(DQS) max

tDQSCK (min)

tQSH tQSL

tDQSCK (min)

tQSH tQSL tQSH tQSL

tDQSCK (min) tDQSCK (min)

tRPST

tHZ(DQS) (min)

Bit 0 Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6 Bit 7

tDQSCK (max)

tRPRE tQSH tQSL

tDQSCK (max)

tQSH tQSL tQSH tQSL

tDQSCK (max) tDQSCK (max) tRPST

tHZ(DQS) (max)

Bit 0 Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6 Bit 7

RL Measured

to this point

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zRead Timing; Data Strobe to Data Relationship

The Data Strobe to Data relationship is shown in the following figure and is applied when the DLL and enabled and

locked.

Rising data strobe edge parameters:

- tDQSQ describes the latest valid transition of the associated DQ pins.

- tQH describes the earliest invalid transition of the associated DQ pins.

Falling data strobe edge parameters:

- tDQSQ describes the latest valid transition of the associated DQ pins.

- tQH describes the earliest invalid transition of the associated DQ pins.

- tDQSQ; both rising/falling edges of DQS, no tAC defined

tDQSQ; both rising/falling edges of DQS, no tAC defined.

Figure 20. Data Strobe to Data Relationship

T1 T2 T3 T4 T5 T6 T7 T8 T9T0 T10

RL = AL +CL

NOPREAD NOP NOP NOP NOP NOP NOP NOP NOP NOP

Bank,

Col n

tDQSQ (max)

Dout

n+1

Dout

n+2

Dout

n+3

Dout

n+4

Dout

n+5

Dout

n+6

Dout

n+7

Dout

n+1

Dout

n+2

Dout

n+3

Dout

n+4

Dout

n+5

Dout

n+6

Dout

n+7

CK#

ADDRESS

COMMAND

DQS,DQS#

(Last data valid)

All DQs collectively

(First data no longer valid)

tRPRE tQH tQH

tDQSQ (max) tRPST

Notes 3

Notes 4

Notes 2

NOTES:

1. BL = 8, RL = 5 (AL = 0, CL = 5)

2. DOUT n = data-out from column n.

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. BL8 setting activated by either MR0[A1:0 = 00] or MR0[A1:0 = 01] and A12 = 1 during READ command at T0.

5. Output timings are referenced to VDDQ/2, and DLL on for locking.

6. tDQSQ defines the skew between DQS,DQS# to Data and does not define DQS,DQS# to Clock.

7. Early Data transitions may not always happen at the same DQ. Data transitions of a DQ can vary (either early or late) within a burst.

Don't CareTRANSITIONING DATA

Dout

n+1

Dout

n+2

Dout

n+3

Dout

n+4

Dout

n+5

Dout

n+6

Dout

n+7

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Write Operation

zDDR3 Burst Operation

During a READ or WRITE command, DDR3 will support BC4 and BL8 on the fly using address A12 during the

READ or WRITE (Auto Precharge can be enabled or disabled).

A12=0, BC4 (BC4 = Burst Chop, tCCD=4)

A12=1, BL8

A12 is used only for burst length control, not as a column address.

zWRITE Timing Violations

Generally, if timing parameters are violated, a complete reset/initialization procedure has to be initiated to make

sure the DRAM works properly. However, it is desirable for certain minor violations that the DRAM is guaranteed

not to “hang up” and errors be limited to that particular operation.

For the following, it will be assumed that there are no timing violations with regard to the Write command itself

(including ODT, etc.) and that it does satisfy all timing requirements not mentioned below.

zData Setup and Hold Violations

Should the strobe timing requirements (tDS, tDH) be violated, for any of the strobe edges associated with a write

burst, then wrong data might be written to the memory location addressed with the offending WRITE command.

Subsequent reads from that location might result in unpredictable read data, however, the DRAM will work properly

otherwise.

zStrobe to Strobe and Strobe to Clock Violations

Should the strobe timing requirements (tDQSH, tDQSL, tWPRE, tWPST) or the strobe to clock timing requirements

(tDSS, tDSH, tDQSS) be violated, for any of the strobe edges associated with a Write burst, then wrong data might

be written to the memory location addressed with the offending WRITE command. Subsequent reads from that

location might result in unpredictable read data, however the DRAM will work properly otherwise.

zWrite Timing Parameters

This drawing is for example only to enumerate the strobe edges that “belong” to a write burst. No actual timing

violations are shown here. For a valid burst all timing parameters for each edge of a burst need to be satisfied (not

only for one edge ).

zRefresh Command

The Refresh command (REF) is used during normal operation of the DDR3 SDRAMs. This command is not

persistent, so it must be issued each time a refresh is required. The DDR3 SDRAM requires Refresh cycles at an

average periodic interval of tREFI. When CS#, RAS#, and CAS# are held Low and WE# High at the rising edge of

the clock, the chip enters a Refresh cycle. All banks of the SDRAM must be precharged and idle for a minimum of

the precharge time tRP(min) before the Refresh Command can be applied. The refresh addressing is generated by

the internal refresh controller. This makes the address bits “Don’t Care” during a Refresh command. An internal

address counter suppliers the address during the refresh cycle. No control of the external address bus is required

once this cycle has started. When the refresh cycle has completed, all banks of the SDRAM will be in the

precharged (idle) state. A delay between the Refresh Command and the next valid command, except NOP or DES,

must be greater than or equal to the minimum Refresh cycle time tRFC(min).

In general, a Refresh command needs to be issued to the DDR3 SDRAM regularly every tREFI interval. To allow for

improved efficiency in scheduling and switching between tasks, some flexibility in the absolute refresh interval is

provided. A maximum of 8 Refresh commands can be postponed during operation of the DDR3 SDRAM, meaning

that at no point in time more than a total of 8 Refresh commands are allowed to be postponed. In case that 8

Refresh commands are postponed in a row, the resulting maximum interval between the surrounding Refresh

commands is limited to 9 x tREFI. A maximum of 8 additional Refresh commands can be issued in advance (“pulled

in”), with each one reducing the number of regular Refresh commands required later by one. Note that pulling in

more than 8 Refresh commands in advance does not further reduce the number of regular Refresh commands

required later, so that the resulting maximum interval between two surrounding Refresh command is limited to 9 x

tREFI. Before entering Self-Refresh Mode, all postponed Refresh commands must be executed.

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zSelf-Refresh Operation

The Self-Refresh command can be used to retain data in the DDR3 SDRAM, even if the reset of the system is

powered down. When in the Self-Refresh mode, the DDR3 SDRAM retains data without external clocking. The

DDR3 SDRAM device has a built-in timer to accommodate Self-Refresh operation. The Self-Refresh Entry (SRE)

Command is defined by having CS#, RAS#, CAS#, and CKE held low with WE# high at the rising edge of the clock.

Before issuing the Self-Refreshing-Entry command, the DDR3 SDRAM must be idle with all bank precharge state

with tRP satisfied. Also, on-die termination must be turned off before issuing Self-Refresh-Entry command, by either

registering ODT pin low “ODTL + 0.5tCK” prior to the Self-Refresh Entry command or using MRS to MR1 command.

Once the Self-Refresh Entry command is registered, CKE must be held low to keep the device in Self-Refresh

mode. During normal operation (DLL on), MR1 (A0=0), the DLL is automatically disabled upon entering Self-

Refresh and is automatically enabled (including a DLL-RESET) upon exiting Self-Refresh.

When the DDR3 SDRAM has entered Self-Refresh mode, all of the external control signals, except CKE and

RESET#, are “don’t care”. For proper Self-Refresh operation, all power supply and reference pins (VDD, VDDQ,

VSS, VSSQ, VRefCA, and VRefDQ) must be at valid levels. The DRAM initiates a minimum of one Refresh

command internally within tCKE period once it enters Self-Refresh mode.

The clock is internally disabled during Self-Refresh operation to save power. The minimum time that the DDR3

SDRAM must remain in Self-Refresh mode is tCKE. The user may change the external clock frequency or halt the

external clock tCKSRE after Self-Refresh entry is registered; however, the clock must be restarted and stable

tCKSRX before the device can exit Self-Refresh mode.

The procedure for exiting Self-Refresh requires a sequence of events. First, the clock must be stable prior to CKE

going back HIGH. Once a Self-Refresh Exit Command (SRX, combination of CKE going high and either NOP or

Deselect on command bus) is registered, a delay of at least tXS must be satisfied before a valid command not

requiring a locked DLL can be issued to the device to allow for any internal refresh in progress.

Before a command which requires a locked DLL can be applied, a delay of at least tXSDLL and applicable ZQCAL

function requirements [TBD] must be satisfied.

Before a command that requires a locked DLL can be applied, a delay of at least tXSDLL must be satisfied.

Depending on the system environment and the amount of time spent in Self-Refresh, ZQ calibration commands

may be required to compensate for the voltage and temperature drift as described in “ZQ Calibration Commands”.

To issue ZQ calibration commands, applicable timing requirements must be satisfied.

CKE must remain HIGH for the entire Self-Refresh exit period tXSDLL for proper operation except for Self-Refresh

re-entry. Upon exit from Self-Refresh, the DDR3 SDRAM can be put back into Self-Refresh mode after waiting at

least tXS period and issuing one refresh command (refresh period of tRFC). NOP or deselect commands must be

registered on each positive clock edge during the Self-Refresh exit interval tXS. ODT must be turned off during

tXSDLL.

The use of Self-Refresh mode instructs the possibility that an internally times refresh event can be missed when

CKE is raised for exit from Self-Refresh mode. Upon exit from Self-Refresh, the DDR3 SDRAM requires a minimum

of one extra refresh command before it is put back into Self-Refresh mode.

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Power-Down Modes

zPower-Down Entry and Exit

Power-Down is synchronously entered when CKE is registered low (along with NOP or Deselect command). CKE is

not allowed to go low while mode register set command, MPR operations, ZQCAL operations, DLL locking or

read/write operation are in progress. CKE is allowed to go low while any of other operation such as row activation,

precharge or auto precharge and refresh are in progress, but power-down IDD spec will not be applied until

finishing those operation.

The DLL should be in a locked state when power-down is entered for fastest power-down exit timing. If the DLL is

not locked during power-down entry, the DLL must be reset after exiting power-down mode for proper read

operation and synchronous ODT operation. DRAM design provides all AC and DC timing and voltage specification

as well proper DLL operation with any CKE intensive operations as long as DRAM controller complies with DRAM

specifications.

During Power-Down, if all banks are closed after any in progress commands are completed, the device will be in

precharge Power-Down mode; if any bank is open after in progress commands are completed, the device will be in

active Power-Down mode.

Entering Power-down deactivates the input and output buffers, excluding CK, CK, ODT, CKE, and RESET#. To protect

DRAM internal delay on CKE line to block the input signals, multiple NOP or Deselect commands are needed during

the CKE switch off and cycle(s) after, this timing period are defined as tCPDED. CKE_low will result in deactivation

of command and address receivers after tCPDED has expired.

Table 24. Power-Dow n Entry Definitions

Status of DRAM MRS bit A12 DLL PD Exit Relevant Parameters

Active

(A Bank or more open) Don't Care On Fast tXP to any valid command.

Precharged

(All Banks Precharged) 0 Off Slow

tXP to any valid command. Since it is in

precharge state, commands here will be ACT,

AR, MRS/EMRS, PR or PRA.

tXPDLL to commands who need DLL to

operate, such as RD, RDA or ODT control line.

Precharged

(All Banks Precharged) 1 On Fast tXP to any valid command.

Also the DLL is disabled upon entering precharge power-down (Slow Exit Mode), but the DLL is kept enabled

during precharge power-down (Fast Exit Mode) or active power-down. In power-down mode, CKE low, RESET#

high, and a stable clock signal must be maintained at the inputs of the DD3 SDRAM, and ODT should be in a valid

state but all other input signals are “Don’t care” (If RESET# goes low during Power-Down, the DRAM will be out of

PD mode and into reset state).

CKE low must be maintain until tCKE has been satisfied. Power-down duration is limited by 9 times tREFI of the

device. The power-down state is synchronously exited when CKE is registered high (along with a NOP or Deselect

command).CKE high must be maintained until tCKE has been satisfied. A valid, executable command can be

applied with power-down exit latency, tXP and/or tXPDLL after CKE goes high. Power-down exit latency is defined

at AC spec table of this datasheet.

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On-Die Termination (ODT)

ODT (On-Die Termination) is a feature of the DDR3 SDRAM that allows the DRAM to turn on/off termination

resistance. For x16 configuration, ODT is applied to each DQU, DQL, DQSU, DQSU#, DQSL, DQSL#, DMU and

DML signal via the ODT control pin. The ODT feature is designed to improve signal integrity of the memory channel

by allowing the DRAM controller to independently turn on/off termination resistance for any or all DRAM devices.

More details about ODT control modes and ODT timing modes can be found further down in this document.

The ODT feature is turned off and not supported in Self-Refresh mode.

A simple functional representation of the DRAM ODT feature is shown as below.

Figure 21. Functional representation of ODT

To other circuitry

like RCV,...

DQ, DQS, DM

ODT

VDDQ / 2

RTT

Switch

The switch is enabled by the internal ODT control logic, which uses the external ODT pin and other control

information. The value of RTT is determined by the settings of Mode Register bits. The ODT pin will be ignored if

the Mode Register MR1 and MR2 are programmed to disable ODT and in self-refresh mode.

zODT Mode Register and ODT Truth Table

The ODT Mode is enabled if either of MR1 {A2, A6, A9} or MR2 {A9, A10} are non-zero. In this case, the value of

RTT is determined by the settings of those bits.

Application: Controller sends WR command together with ODT asserted.

One possible application: The rank that is being written to provides termination.

DRAM turns ON termination if it sees ODT asserted (except ODT is disabled by MR)

DRAM does not use any write or read command decode information.

Table 25. Termination Truth Table

ODT pin DRAM Termination State

0 OFF

1 On, (Off, if disabled by MR1 (A2, A6, A9) and MR2 (A9, A10) in gereral)

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zSynchronous ODT Mode

Synchronous ODT mode is selected whenever the DLL is turned on and locked. Based on the power-down

definition, these modes are:

- Any bank active with CKE high

- Refresh with CKE high

- Idle mode with CKE high

- Active power down mode (regardless of MR0 bit A12)

- Precharge power down mode if DLL is enabled during precharge power down by MR0 bit A12

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.

In synchronous ODT mode, RTT will be turned on ODTLon clock cycles after ODT is sampled high by a rising clock

edge and turned off ODTLoff clock cycles after ODT is registered low by a rising clock edge. The ODT latency is

tied to the write latency (WL) by: ODTLon = WL - 2; ODTLoff = WL-2.

zODT Latency and Posted ODT

In synchronous ODT Mode, the Additive Latency (AL) programmed into the Mode Register (MR1) also applies to

the ODT signal. The DRAM internal ODT signal is delayed for a number of clock cycles defined by the Additive

Latency (AL) relative to the external ODT signal. ODTLon = CWL + AL - 2; ODTLoff = CWL + AL - 2. For details,

refer to DDR3 SDRAM latency definitions.

Table 26. ODT Latency

Symbol Parameter DDR3-1600 Unit

ODTLon ODT turn on

Latency WL – 2 = CWL + AL -2 tCK

ODTLoff ODT turn off

Latency WL – 2 = CWL + AL -2 tCK

zTiming Parameters

In synchronous ODT mode, the following timing parameters apply: ODTLon, ODTLoff, tAON min/max, tAOF

min/max.

Minimum RTT turn-on time (tAON min) is the point in time when the device leaves high impedance and ODT

resistance begins to turn on. Maximum RTT turn-on time (tAON max) is the point in time when the ODT resistance

is fully on. Both are measured from ODTLon.

Minimum RTT turn-off time (tAOF min) is the point in time when the device starts to turn off the ODT resistance.

Maximum RTT turn off time (tAOF max) is the point in time when the on-die termination has reached high

impedance. Both are measured from ODTLoff.

When ODT is asserted, it must remain high until ODTH4 is satisfied. If a Write command is registered by the

SDRAM with ODT high, then ODT must remain high until ODTH4 (BL=4) or ODTH8 (BL=8) after the write

command. ODTH4 and ODTH8 are measured from ODT registered high to ODT registered low or from the

registration of a write command until ODT is registered low.

zODT during Reads

As the DDR3 SDRAM cannot terminate and drive at the same time, RTT must be disabled at least half a clock cycle

before the read preamble by driving the ODT pin low appropriately. RTT may not be enabled until the end of the

post-amble as shown in the following figure. DRAM turns on the termination when it stops driving which is

determined by tHZ. If DRAM stops driving early (i.e. tHZ is early), then tAONmin time may apply. If DRAM stops

driving late (i.e. tHZ is late), then DRAM complies with tAONmax timing. Note that ODT may be disabled earlier

before the Read and enabled later after the Read than shown in this example.

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Figure 22. ODT must be disabled externally during Reads by driving ODT low

(CL=6; AL=CL-1=5; RL=AL+CL=11; CWL=5; ODTLon=CWL+AL-2=8; ODTLoff=CWL+AL-2=8)

NOPREAD NOP NOP NOP NOP NOP NOP NOP NOP NOP NOP

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP NOP NOP

Don't CareTRANSITI O N ING DATA

T15

NOP

ODT

T16 T17

NOP NOP

ODTLon = CWL + AL - 2

ODTLoff = CWL + AL - 2

RL = AL + CL

tAOF(min)

tAOF(max) tAON(max)

VALID

RTT RTT_NOM RTT_NOM

Din

b+1

Din

b+2

Din

b+3

Din

b+4

Din

b+5

Din

b+6

COMMAND

ADDRESS

DQS, DQS#

Din

b+7

zDynamic 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. This requirement is

supported by the “Dynamic ODT” feature as described as follows:

Functional Description

The Dynamic ODT Mode is enabled if bit (A9) or (A10) of MR2 is set to ‘1’. The function is described as follows:

Two RTT values are available: RTT_Nom and RTT_WR.

- The value for RTT_Nom is preselected via bits A[9,6,2] in MR1.

- The value for RTT_WR is preselected via bits A[10,9] in MR2.

During operation without write commands, the termination is controlled as follows:

- Nominal termination strength RTT_Nom is selected.

- Termination on/off timing is controlled via ODT pin and latencies ODTLon and ODTLoff.

When a Write command (WR, WRA, WRS4, WRS8, WRAS4, WRAS8) is registered, and if Dynamic ODT is

enabled, the termination is controlled as follows:

-A latency ODTLcnw after the write command, termination strength RTT_WR is selected.

-A latency ODTLcwn8 (for BL8, fixed by MRS or selected OTF) or ODTLcwn4 (for BC4, fixed by MRS or

selected OTF) after the write command, termination strength RTT_Nom is selected.

- Termination on/off timing is controlled via ODT pin and ODTLon, ODTLoff.

The following table shows latencies and timing parameters which are relevant for the on-die termination control in

Dynamic ODT 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.

When ODT is asserted, it must remain high until ODTH4 is satisfied. If a Write command is registered by the

SDRAM with ODT high, then ODT must remain high until ODTH4 (BL=4) or ODTH8 (BL=8) after the Write

command. ODTH4 and ODTH8 are measured from ODT registered high to ODT registered low or from the

registration of Write command until ODT is register low.

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Table 27. Latencies and timing parameters relevant for Dynamic ODT

Name and

Description Abbr. Defined from Defined to Definition for all DDR3

speed pin Unit

ODT turn-on

Latency ODTLon registering external

ODT signal high

turning

termination on ODTLon=WL-2 tCK

ODT turn-off

Latency ODTLoff registering external

ODT signal low

turning

termination off ODTLoff=WL-2 tCK

ODT Latency for

changing from

RTT_Nom to

RTT_WR

ODTLcnw registering external

write command

change RTT

strength from

RTT_Nom to

RTT_WR

ODTLcnw=WL-2 tCK

ODT Latency for

change from

RTT_WR to

RTT_Nom (BL=4)

ODTLcwn4 registering external

write command

change RTT

strength from

RTT_WR to

RTT_Nom

ODTLcwn4=4+ODTLoff tCK

ODT Latency for

change from

RTT_WR to

RTT_Nom (BL=8)

ODTLcwn8 registering external

write command

change RTT

strength from

RTT_WR to

RTT_Nom

ODTLcwn8=6+ODTLoff tCK (avg)

Minimum ODT high time

after ODT assertion ODTH4 registering ODT high ODT registered

low ODTH4=4 tCK (avg)

Minimum ODT

high time

after Write (BL=4)

ODTH4 registering write with

ODT high

ODT registered

low ODTH4=4 tCK (avg)

Minimum ODT

high time

after Write (BL=8)

ODTH8 registering write with

ODT high ODT register low ODTH8=6 tCK (avg)

RTT change skew tADC ODTLcnw

ODTLcwn RTT valid tADC(min)=0.3tCK(avg)

tADC(max)=0.7tCK(avg) tCK (avg)

Note 1: tAOF,nom and tADC,nom are 0.5tCK (effectively adding half a clock cycle to ODTLoff, ODTcnw, and ODTLcwn)

zAsynchronous ODT Mode

Asynchronous ODT mode is selected when DRAM runs in DLLon mode, but DLL is temporarily disabled (i.e. frozen)

in precharge power-down (by MR0 bit A12). Based on the power down mode definitions, this is currently Precharge

power down mode if DLL is disabled during precharge power down by MR0 bit A12.

In asynchronous ODT timing mode, internal ODT command is NOT delayed by Additive Latency (AL) relative to the

external ODT command.

In asynchronous ODT mode, the following timing parameters apply: tAONPD min/max, tAOFPD min/max.

Minimum RTT turn-on time (tAONPD min) is the point in time when the device termination circuit leaves high

impedance state and ODT resistance begins to turn on. Maximum RTT turn on time (tAONPD max) is the point in

time when the ODT resistance is fully on.

tAONPDmin and tAONPDmax are measured from ODT being sampled high.

Minimum RTT turn-off time (tAOFPDmin) is the point in time when the devices termination circuit starts to turn off

the ODT resistance. Maximum ODT turn off time (tAOFPDmax) is the point in time when the on-die termination has

reached high impedance. tAOFPDmin and tAOFPDmax are measured from ODT being sample low.

Table 28. ODT timing parameters for Power Dow n (with DLL frozen) entry and exit

Description Min Max

ODT to RTT

turn-on delay

min{ ODTLon * tCK + tAONmin; tAONPDmin }

min{ (WL - 2) * tCK + tAONmin; tAONPDmin }

max{ ODTLon * tCK + tAONmax; tAONPDmax }

max{ (WL - 2) * tCK + tAONmax; tAONPFmax }

ODT to RTT

turn-off delay

min{ ODTLoff * tCK + tAOFmin; tAOFPDmin }

min{ (WL - 2) * tCK + tAOFmin; tAOFPDmin }

max{ ODTLoff * tCK + tAOFmax; tAOFPDmax }

max{ (WL - 2) * tCK + tAOFmax; tAOFPDmax }

tANPD WL - 1

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zSynchronous to Asynchronous ODT Mode Transition during Power-Down Entry

If DLL is selected to be frozen in Precharge Power Down Mode by the setting of bit A12 in MR0 to “0”, there is a

transition period around power down entry, where the DDR3 SDRAM may show either synchronous or

asynchronous ODT behavior.

The transition period is defined by the parameters tANPD and tCPDED(min). tANPD is equal to (WL-1) and is

counted backwards in time from the clock cycle where CKE is first registered low. tCPDED(min) starts with the

clock cycle where CKE is first registered low. The transition period begins with the starting point of tANPD and

terminates at the end point of tCPDED(min). If there is a Refresh command in progress while CKE goes low, then

the transition period ends at the later one of tRFC(min) after the Refresh command and the end point of

tCPDED(min). Please note that the actual starting point at tANPD is excluded from the transition period, and the

actual end point at tCPDED(min) and tRFC(min, respectively, are included in the transition period.

ODT assertion during the transition period may result in an RTT changes as early as the smaller of tAONPDmin and

(ODTLon*tck+tAONmin) and as late as the larger of tAONPDmax and (ODTLon*tCK+tAONmax). ODT de-assertion

during the transition period may result in an RTT change as early as the smaller of tAOFPDmin and

(ODTLoff*tCK+tAOFmin) and as late as the larger of tAOFPDmax and (ODTLoff*tCK+tAOFmax). Note that, if AL

has a large value, the range where RTT is uncertain becomes quite large. The following figure shows the three

different cases: ODT_A, synchronous behavior before tANPD; ODT_B has a state change during the transition

period; ODT_C shows a state change after the transition period.

zAsynchronous to Synchronous ODT Mode transition during Power-Down Exit

If DLL is selected to be frozen in Precharge Power Down Mode by the setting of bit A12 in MR0 to “0”, there is also

a transition period around power down exit, where either synchronous or asynchronous response to a change in

ODT must be expected from the DDR3 SDRAM.

This transition period starts tANPD before CKE is first registered high, and ends tXPDLL after CKE is first registered

high. tANPD is equal to (WL -1) and is counted (backwards) from the clock cycle where CKE is first registered high.

ODT assertion during the transition period may result in an RTT change as early as the smaller of tAONPDmin and

(ODTLon* tCK+tAONmin) and as late as the larger of tAONPDmax and (ODTLon*tCK+tAONmax). ODT de-

assertion during the transition period may result in an RTT change as early as the smaller of tAOFPDmin and

(ODTLoff*tCK+tAOFmin) and as late as the larger of tAOFPDmax and (ODToff*tCK+tAOFmax). Note that if AL has

a large value, the range where RTT is uncertain becomes quite large. The following figure shows the three different

cases: ODT_C, asynchronous response before tANPD; ODT_B has a state change of ODT during the transition

period; ODT_A shows a state change of ODT after the transition period with synchronous response.

zAsynchronous to Synchronous ODT Mode during short CKE high and short CKE low periods

If the total time in Precharge Power Down state or Idle state is very short, the transition periods for PD entry and PD

exit may overlap. In this case, the response of the DDR3 SDRAMs RTT to a change in ODT state at the input may

be synchronous or asynchronous from the state of the PD entry transition period to the end of the PD exit transition

period (even if the entry ends later than the exit period).

If the total time in Idle state is very short, the transition periods for PD exit and PD entry may overlap. In this case,

the response of the DDR3 SDRAMs RTT to a change in ODT state at the input may be synchronous or

asynchronous from the state of the PD exit transition period to the end of the PD entry transition period. Note that in

the following figure, it is assumed that there was no Refresh command in progress when Idle state was entered.

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ZQ Calibration Commands

zZQ Calibration Description

ZQ Calibration command is used to calibrate DRAM Ron and ODT values. DDR3 SDRAM needs longer time to

calibrate output driver and on-die termination circuits at initialization and relatively smaller time to perform periodic

calibrations.

ZQCL command is used to perform the initial calibration during power-up initialization sequence. This command

may be issued at any time by the controller depending on the system environment. ZQCL command triggers the

calibration engine inside the DRAM and once calibration is achieved the calibrated values are transferred from

calibration engine to DRAM IO which gets reflected as updated output driver and on-die termination values.

The first ZQCL command issued after reset is allowed a timing period of tZQinit to perform the full calibration and

the transfer of values. All other ZQCL commands except the first ZQCL command issued after RESET is allowed a

timing period of tZQoper.

ZQCS command is used to perform periodic calibrations to account for voltage and temperature variations. A

shorter timing window is provided to perform the calibration and transfer of values as defined by timing parameter

tZQCS.

No other activities should be performed on the DRAM channel by the controller for the duration of tZQinit, tZQoper,

or tZQCS. The quiet time on the DRAM channel allows calibration of output driver and on-die termination values.

Once DRAM calibration is achieved, the DRAM should disable ZQ current consumption path to reduce power.

All banks must be precharged and tRP met before ZQCL or ZQCS commands are issued by the controller.

ZQ calibration commands can also be issued in parallel to DLL lock time when coming out of self refresh. Upon

self-refresh exit, DDR3/L SDRAM will not perform an IO calibration without an explicit ZQ calibration command. The

earliest possible time for ZQ Calibration command (short or long) after self refresh exit is tXS.

In systems that share the ZQ resistor between devices, the controller must not allow any overlap of tZQoper, tZQinit,

or tZQCS between ranks.

Figure 23. ZQ Calibration Timing

CK# T1 Ta0 Ta1 Ta2 Ta3T0

CKE

NOPZQCL NOP VALID

tZQinit or tZQoper

Don't CareTIME BREAK

VALID

Tb0 Tb1

ZQCS NOP

tZQCS

Tc0 Tc1

NOP NOP

ADDRESS

NOTES:

1. CKE must be continuously registered high during the calibration procedure.

2. On-die termination must be disabled via the ODT signal or MRS during the calibration procedure.

3. All devices connected to the DQ bus should be high impedance during the calibration procedure.

Tc2

NOP VALID

VALID VALID VALID

A10 VALID VALID VALID

VALID

VALID VALID

Notes 1

ODT VALID

VALID VALID

Notes 2

Hi-Z ACTIVITIES Hi-Z

Notes 3

COMMAND

DQ Bus ACTIVITIES

Notes 1

Notes 2

Notes 3

zZQ External Resistor Value, Tolerance, and Capacitive loading

In order to use the ZQ calibration function, a 240 ohm +/- 1% tolerance external resistor connected between the ZQ

pin and ground. The single resistor can be used for each SDRAM or one resistor can be shared between two

SDRAMs if the ZQ calibration timings for each SDRAM do not overlap. The total capacitive loading on the ZQ pin

must be limited.

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- Single-ended requirements for differential signals

Each individual component of a differential signal (CK, CK#, LDQS, UDQS, LDQS#, or UDQS#) 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 ADD/CMD signals) in every half-cycle. LDQS, UDQS, LDQS#, UDQS# have to reach VSEHmin /

VSELmax (approximately the ac-levels (VIH(ac) / VIL(ac)) for DQ signals) in every half-cycle proceeding and

following a valid transition.

Note that the applicable ac-levels for ADD/CMD and DQ’s might be different per speed-bin etc. E.g., if

VIH150(ac)/VIL150(ac) is used for ADD/CMD signals, then these ac-levels apply also for the single-ended signals

CK and CK#.

Table 29. Single-ended levels for CK, DQSL, DQSU, CK#, DQSL# or DQSU#

Symbol Parameter Min. Max.

Unit Note

Single-ended high level for strobes (VDD / 2) + 0.175 Note 3 V 1,2

VSEH Single-ended high level for CK, CK# (VDD / 2) + 0.175 Note 3 V 1,2

Single-ended low level for strobes Note 3 (VDD / 2) - 0.175 V 1,2

VSEL Single-ended low level for CK, CK# Note 3 (VDD / 2) - 0.175 V 1,2

NOTE 1: For CK, CK# use VIH/VIL(ac) of ADD/CMD; for strobes (DQSL, DQSL#, DQSU, DQSU#) use VIH/VIL(ac) of DQs.

NOTE 2: VIH(ac)/VIL(ac) for DQs is based on VREFDQ; VIH(ac)/VIL(ac) for ADD/CMD 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.

NOTE 3: These values are not defined, however the single-ended signals CK, CK#, DQSL, DQSL#, DQSU, DQSU# 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.

- Differential Input Cross Point Voltage

To guarantee tight setup and hold times as well as output skew parameters with respect to clock and strobe, each

cross point voltage of differential input signals (CK, CK# and DQS, DQS#) must meet the requirements in the

following table. The differential input cross point voltage Vix is measured from the actual cross point of true and

complete signal to the midlevel between of VDD and VSS.

Table 30. Cross point voltage for differential input signals (CK, DQS)

Symbol Parameter Min. Max.

Unit Note

- 150 150 mV 2

VIX(CK) Differential Input Cross Point Voltage

relative to VDD/2 for CK, CK# - 175 175 mV 1

VIX(DQS) Differential Input Cross Point Voltage

relative to VDD/2 for DQS, DQS# - 150 150 mV 2

NOTE 1: Extended range for Vix is only allowed for clock and if single-ended clock input signals CK and CK# are monotonic

with a single-ended swing VSEL / VSEH of at least VDD/2 +/-250 mV, and when the differential slew rate of CK -

CK# is larger than 3 V/ns.

NOTE 2: The relation between Vix Min/Max and VSEL/VSEH should satisfy following.

(VDD/2) + Vix (Min) - VSEL ≧ 25mV

VSEH - ((VDD/2) + Vix (Max)) ≧ 25mV

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- Slew Rate Definition for Differential Input Signals

Input slew rate for differential signals (CK, CK# and DQS, DQS#) are defined and measured as shown below.

Table 31. Differential Input Slew Rate Definition

Measured

Description From To Defined by

Differential input slew rate for rising edge

(CK, CK# and DQS, DQS#) VILdiffmax VIHdiffmin [VIHdiffmin-VILdiffmax] / DeltaTRdiff

Differential input slew rate for falling edge

(CK, CK# and DQS, DQS#) VIHdiffmin VILdiffmax [VIHdiffmin-VILdiffmax] / DeltaTFdiff

NOTE: The differential signal (i.e., CK, CK# and DQS, DQS#) must be linear between these thresholds.

Table 32. Single-ended AC and DC Output Levels

Symbol Parameter -12 Unit Note

VOH(DC) DC output high measurement level (for IV curve linearity) 0.8 x VDDQ V

VOM(DC) DC output mid measurement level (for IV curve linearity) 0.5 x VDDQ V

VOL(DC) DC output low measurement level (for IV curve linearity) 0.2 x VDDQ V

VOH(AC) AC output high measurement level (for output SR) VTT + 0.1 x VDDQ V 1

VOL(AC) AC output low measurement level (for output SR) VTT - 0.1 x VDDQ V 1

NOTE 1: 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 40Ω and an effective test load of 25Ω to VTT = VDDQ/2.

Table 33. Differential AC and DC Output Levels

Symbol Parameter -12 Unit Note

VOHdiff(AC) AC differential output high measurement level (for output SR) + 0.2 x VDDQ V 1

VOLdiff(AC) AC differential output low measurement level (for output SR) - 0.2 x VDDQ V 1

NOTE 1: 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 40Ω and an effective test load of 25Ω to VTT = VDDQ/2 at each of the differential outputs.

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- Single Ended Output Slew Rate

With the reference load for timing measurements, output slew rate for falling and rising edges is defined and

measured between VOL(AC) and VOH(AC) for single ended signals as shown in Table.

Table 34. Output Slew Rate Definition (Single-ended)

Measured

Description From To Defined by

Single-ended output slew rate for rising edge VOL(AC) VOH(AC) [VOH(AC) - VOL(AC)] / DeltaTRse

Single-ended output slew rate for falling edge VOH(AC) VOL(AC) [VOH(AC) - VOL(AC)] / DeltaTFse

NOTE: Output slew rate is verified by design and characterization, and may not be subject to production test.

Table 35. Output Slew Rate (Single-ended) -12

Symbol Parameter Min. Max. Unit

SRQse Single-ended Output Slew Rate 2.5 5 V/ns

Description:

SR: Slew Rate

Q: Query Output (like in DQ, which stands for Data-in, Query-Output)

se: Single-ended Signals

For Ron = RZQ/7 setting

- Differential Output Slew Rate

With the reference load for timing measurements, output slew rate for falling and rising edges is defined and

measured between VOLdiff(AC) and VOHdiff(AC) for differential signals as shown in Table.

Table 36. Output Slew Rate Definition (Differential)

Measured

Description From To Defined by

Differential output slew rate for rising edge VOLdiff(AC) VOHdiff(AC) [VOHdiff(AC) - VOLdiff(AC)] /

DeltaTRdiff

Differential output slew rate for falling edge VOHdiff(AC) VOLdiff(AC) [VOHdiff(AC) - VOLdiff(AC)] /

DeltaTFdiff

NOTE: Output slew rate is verified by design and characterization, and may not be subject to production test.

Table 37. Output Slew Rate (Differential) -12

Symbol Parameter Min. Max. Unit

SRQdiff Differential Output Slew Rate 5 10 V/ns

Description:

SR: Slew Rate

Q: Query Output (like in DQ, which stands for Data-in, Query-Output)

diff: Differential Signals

For Ron = RZQ/7 setting

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zReference Load for AC Timing and Output Slew Rate

The following figure represents the effective reference load of 25 ohms used in defining the relevant AC timing

parameters of the device as well as output slew rate measurements.

It is not intended as a precise representation of any particular system environment or a depiction of the actual load

presented by a production tester. System designers should use IBIS or other simulation tools to correlate the timing

reference load to a system environment. Manufacturers correlate to their production test conditions, generally one

or more coaxial transmission lines terminated at the tester electronics.

Figure 24. Reference Load for AC Timing and Output Slew Rate

DUT

DQS

DQS#

VDDQ

CK, CK# 25 Ohm

VTT = VDDQ/2

Table 38. AC Overshoot/Undershoot Specification for Address and Control Pins

Parameter -12

Unit

Maximum peak amplitude allowed for overshoot area. 0.4

Maximum peak amplitude allowed for undershoot area. 0.4

Maximum overshoot area above VDD 0.33

V-ns

Maximum undershoot area below VSS 0.33

V-ns

Table 39. AC Overshoot/Undershoot Specification for Clock, Data, Strobe and Mask

Parameter -12

Unit

Maximum peak amplitude allowed for overshoot area. 0.4

Maximum peak amplitude allowed for undershoot area. 0.4

Maximum overshoot area above VDD 0.13 V-ns

Maximum undershoot area below VSS 0.13 V-ns

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- Address / Command Setup, Hold and Derating

For all input signals the total tIS (setup time) and tIH (hold time) required is calculated by adding the data sheet

tIS(base) and tIH(base) and tIH(base) value to the delta tIS and delta tIH derating value respectively.

Example: tIS (total setup time) = tIS(base) + delta tIS.

Setup (tIS) nominal slew rate for a rising signal is defined as the slew rate between the last crossing of Vref(dc) and

the first crossing of VIH(ac)min. Setup (tIS) nominal slew rate for a falling signal is defined as the slew rate between

the last crossing of Vref(dc) and the first crossing of VIL(ac)max. If the actual signal is always earlier than the

nominal slew rate line between shaded ‘Vref(dc) to ac region’, use nominal slew rate for derating value. If the actual

signal is later than the nominal slew rate line anywhere between shaded ‘Vref(dc) to ac region’, the slew rate of the

tangent line to the actual signal from the ac level to dc level is used for derating value.

Hold (tIH) nominal slew rate for a rising signal is defined as the slew rate between the last crossing of VIL(dc)max

and the first crossing of Vref(dc). Hold (tIH) nominal slew rate for a falling signal is defined as the slew rate between

the last crossing of VIH(dc)min and the first crossing of Vref(dc). If the actual signal is always later than the nominal

slew rate line between shaded ‘dc to Vref(dc) region’, use nominal slew rate for derating value. If the actual signal is

earlier than the nominal slew rate line anywhere between shaded ‘dc to Vref(dc) region’, the slew rate of a tangent

line to the actual signal from the dc level to Vref(dc) level is used for derating value. For a valid transition the input

signal has to remain above/below VIH/IL(ac) for some time tVAC. Although for slow slew rates the total setup time

might be negative (i.e. a valid input signal will not have reached VIH/IL(ac) at the time of the rising clock transition) a

valid input signal is still required to complete the transition and reach VIH/IL(ac).

Table 40. ADD/CMD Setup and Hold Base - Values for 1V/ns

Symbol Reference -12 Unit

tIS(base) AC175 VIH/L(ac) 45 ps

tIS(base) AC150 VIH/L(ac) 170 ps

tIS(base) AC135 VIH/L(ac) - ps

tIH(base) DC100 VIH/L(dc) 120 ps

NOTE 1: (ac/dc referenced for 1V/ns Address/Command slew rate and 2 V/ns differential CK-CK# slew rate)

NOTE 2: The tIS(base) AC150 (AC135) specifications are adjusted from the tIS(base) specification by adding an additional

100ps of derating to accommodate for the lower alternate threshold of 150 mV (135mV) and another 25 ps to account

for the earlier reference point [(175 mv - 150 mV) / 1 V/ns].

Table 41. Derating values DDR3-1600 tIS/tIH – (AC175)

t△IS, t△IH derating in [ps] AC/DC based AC175 Threshold -> VIH(ac)=VREF(dc)+175mV, VIL(ac)=VREF(dc)-175mV

CK, CK# Differential Slew Rate

4.0 V/ns 3.0 V/ns 2.0 V/ns 1.8 V/ns 1.6 V/ns 1.4 V/ns 1.2 V/ns 1.0 V/ns

△tIS △tIH △tIS △tIH △tIS △tIH △tIS △tIH △tIS △tIH △tIS △tIH △tIS △tIH △tIS △tIH

2.0 88 50 88 50 88 50 96 58 104 66 112 74 120 84 128 100

1.5 59 34 59 34 59 34 67 42 75 50 83 58 91 68 99 84

1.0 0 0 0 0 0 0 8 8 16 16 24 24 32 34 40 50

0.9 -2 -4 -2 -4 -2 -4 6 4 14 12 22 20 30 30 38 46

0.8 -6 -10 -6 -10 -6 -10 2 -2 10 6 18 14 26 24 34 40

0.7 -11 -16 -11 -16 -11 -16 -3 -8 5 0 13 8 21 18 29 34

0.6 -17 -26 -17 -26 -17 -26 -9 -18 -1 -10 7 -2 15 8 23 24

0.5 -35 -40 -35 -40 -35 -40 -27 -32 -19 -24 -11 -16 -2 -6 5 10

CMD

/ADD

Slew

Rate

V/ns

0.4 -62 -60 -62 -60 -62 -60 -54 -52 -46 -44 -38 -36 -30 -26 -22 -10

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Table 42. Derating values DDR3-1600 tIS/tIH – (AC150)

t△IS, t△IH derating in [ps] AC/DC based Alternate AC150 Threshold -> VIH(ac)=VREF(dc)+150mV, VIL(ac)=VREF(dc)-150mV

CK, CK# Differential Slew Rate

4.0 V/ns 3.0 V/ns 2.0 V/ns 1.8 V/ns 1.6 V/ns 1.4 V/ns 1.2 V/ns 1.0 V/ns

△tIS △tIH △tIS △tIH △tIS △tIH △tIS △tIH △tIS △tIH △tIS △tIH △tIS △tIH △tIS △tIH

2.0 75 50 75 50 75 50 83 58 91 66 99 74 107 84 115 100

1.5 50 34 50 34 50 34 58 42 66 50 74 58 82 68 90 84

1.0 0 0 0 0 0 0 8 8 16 16 24 24 32 34 40 50

0.9 0 -4 0 -4 0 -4 8 4 16 12 24 20 32 30 40 46

0.8 0 -10 0 -10 0 -10 8 -2 16 6 24 14 32 24 40 40

0.7 0 -16 0 -16 0 -16 8 -8 16 0 24 8 32 18 40 34

0.6 -1 -26 -1 -26 -1 -26 7 -18 15 -10 23 -2 31 8 39 24

0.5 -10 -40 -10 -40 -10 -40 -2 -32 6 -24 14 -16 22 -6 30 10

CMD

/ADD

Slew

Rate

V/ns

0.4 -25 -60 -25 -60 -25 -60 -17 -52 -9 -44 -1 -36 7 -26 15 -10

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- Data Setup, Hold, and Slew Rate De-rating

For all input signals the total tDS (setup time) and tDH (hold time) required is calculated by adding the data sheet

tDS(base) and tDH(base) value to the ΔtDS and ΔtDH derating value respectively.

Example: tDS (total setup time) = tDS(base) + ΔtDS.

Setup (tDS) nominal slew rate for a rising signal is defined as the slew rate between the last crossing of Vref(dc)

and the first crossing of VIH(ac)min. Setup (tDS) nominal slew rate for a falling signal is defined as the slew rate

between the last crossing of Vref(dc) and the first crossing of VIL(ac)max. If the actual signal is always earlier than

the nominal slew rate line between shaded ‘Vref(dc) to ac region’, use nominal slew rate for derating value. If the

actual signal is later than the nominal slew rate line anywhere between shaded ‘Vref(dc) to ac region’, the slew rate

of the tangent line to the actual signal from the ac level to dc level is used for derating value. Hold (tDH) nominal

slew rate for a rising signal is defined as the slew rate between the last crossing of VIL(dc)max and the first

crossing of Vref(dc). Hold (tDH) nominal slew rate for a falling signal is defined as the slew rate between the last

crossing of VIH(dc)min and the first crossing of Vref(dc). If the actual signal is always later than the nominal slew

rate line between shaded ‘dc level to Vref(dc) region’, use nominal slew rate for derating value. If the actual signal is

earlier than the nominal slew rate line anywhere between shaded ‘dc to Vref(dc) region’, the slew rate of a tangent

line to the actual signal from the dc level to Vref(dc) level is used for derating value.

For a valid transition the input signal has to remain above/below VIH/IL(ac) for some time tVAC.

Although for slow slew rates the total setup time might be negative (i.e. a valid input signal will not have reached

VIH/IL(ac) at the time of the rising clock transition) a valid input signal is still required to complete the transition and

reach VIH/IL(ac).

For slew rates in between the values listed in the following tables, the derating values may be obtained by linear

interpolation.

These values are typically not subject to production test. They are verified by design and characterization.

Table 43. Data Setup and Hold Base

Symbol Reference -12 Unit Note

tDS(base) AC150 VIH/L(ac) 10 ps 2

tDS(base) AC135 VIH/L(ac) - ps 1

tDH(base) DC100 VIH/L(dc) - ps 1

tDH(base) DC100 VIH/L(dc) 45 ps 2

NOTE 1: (ac/dc referenced for 2V/ns DQ- slew rate and 4 V/ns differential DQS slew rate)

NOTE 2: (ac/dc referenced for 1V/ns DQ- slew rate and 2 V/ns differential DQS slew

rate)

Table 44. Derating values for DDR3-1600 tDS/tDH – (AC150)

t△DS, t△DH derating in [ps] AC/DC based

DQS, DQS# Differential Slew Rate

4.0 V/ns 3.0 V/ns 2.0 V/ns 1.8 V/ns 1.6 V/ns 1.4 V/ns 1.2 V/ns 1.0 V/ns

△tDS △tDH △tDS △tDH △tDS △tDH △tDS △tDH △tDS △tDH △tDS △tDH △tDS △tDH △tDS △tDH

2.0 75 50 75 50 75 50 - - - - - - - - - -

1.5 50 34 50 34 50 34 58 42 - - - - - - - -

1.0 0 0 0 0 0 0 8 8 16 16 - - - - - -

0.9 - - 0 -4 0 -4 8 4 16 12 24 20 - - - -

0.8 - - - - 0 -10 8 -2 16 6 24 14 32 24 - -

0.7 - - - - - - 8 -8 16 0 24 8 32 18 40 34

0.6 - - - - - - - - 15 -10 23 -2 31 8 39 24

0.5 - - - - - - - - - - 14 -16 22 -6 30 10

Slew

Rate

V/ns

0.4 - - - - - - - - - - - - 7 -26 15 -10

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Timing Waveforms

Figure 25. MPR Readout of predefined pattern,BL8 fixed burst order, single readout

Don't CareTIME BREAK

MRSPREA READ NOP NOP NOP NOP NOP NOP NOP NOP MRS

tRP

NOTES:

1. RD with BL8 either by MRS or OTF.

2. Memory Contro ller must drive 0 on A[2:0].

T0 Ta Tb0 Tb1 Tc0 Tc1 Tc2 Tc3 Tc4 Tc5 Tc6 Tc7

CK#

A[1:0]

A[2]

A[11]

A12, BC#

A[9:3]

A10, AP

Tc8 Tc9 Td

MRS MRS VALID

tMOD Notes 1

tMPRR tMOD

3VALID 3

0 0 VALID

1 0 0

00 VALID 00

0VALID 0

A[14:13]

Notes 2

DQS, DQS#

COMMAND

Figure 26. MPR Readout of predefined pattern,BL8 fixed burst order, back to back radout

Don't CareTIME BREAK

MRSPREA READ READ NOP NOP NOP NOP NOP NOP NOP NOP

tRP

NOTES:

1. RD with BL8 either by MRS or OTF.

2. Memory Controller must drive 0 on A[2:0].

T0 Ta Tb Tc0 Tc1 Tc2 Tc3 Tc4 Tc5 Tc6 Tc7 Tc8

CK#

A[1:0]

A[2]

A[11]

A12, BC#

A[9:3]

A10, AP

Tc9 Tc10 Td

NOP MRS VALID

tMOD Notes 1

tMPRR tMOD

3VALID 3

0 0 VALID

1 0 0

00 VALID 00

0VALID 0

A[14:13]

Notes 2

Notes 1

tCCD

VALID

Notes 2

Notes 1 Notes 1

Notes 2

DQS, DQS#

COMMAND

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Figure 27. MPR Readout of predefined pattern,BC4 lower nibble then upper nibble

Don't CareTIME BREAK

MRSPREA READ READ NOP NOP NOP NOP NOP NOP NOP MRS

tRP

NOTES:

1. RD with BC4 either by MRS or OTF.

2. Memory Controller must drive 0 on A[1:0].

3. A[2]=0 selects lower 4 nibb le bits 0....3.

4. A[2]=1 selects upper 4 nibble bits 4....7.

T0 Ta Tb Tc0 Tc1 Tc2 Tc3 Tc4 Tc5 Tc6 Tc7 Tc8

CK#

A[1:0]

A[2]

A[11]

A12, BC#

A[9:3]

A10, AP

Tc9 Tc10 Td

NOP NOP VALID

tMOD Notes 1

tMPRR tMOD

3VALID 3

0 0 VALID

1 0 0

00 VALID 00

0VALID 0

A[14:13]

Notes 2

Notes 3

Notes 1

tCCD

VALID

Notes 2

Notes 1 Notes 1

Notes 4

DQS, DQS#

COMMAND

Figure 28. MPR Readout of predefined pattern,BC4 upper nibble then lower nibble

Don't CareTIME BREAK

MRSPREA READ READ NOP NOP NOP NOP NOP NOP NOP MRS

tRP

NOTES:

1. RD with BC4 either by MRS or OTF.

2. Memory Controller must drive 0 on A[1:0].

3. A[2]=0 selects lower 4 nibble bits 0....3.

4. A[2]=1 selects upper 4 nibble bits 4....7.

T0 Ta Tb Tc0 Tc1 Tc2 Tc3 Tc4 Tc5 Tc6 Tc7 Tc8

CK#

A[1:0]

A[2]

A[11]

A12, BC#

A[9:3]

A10, AP

Tc9 Tc10 Td

NOP NOP VALID

tMOD Notes 1

tMPRR tMOD

3VALID 3

0 0 VALID

1 1 0

00 VALID 00

0VALID 0

A[14:13]

Notes 2

Notes 4

Notes 1

tCCD

VALID

Notes 2

Notes 1 Notes 1

Notes 3

DQS, DQS#

COMMAND

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Figure 29. READ (BL8) to READ (BL8)

NOPREAD NOP NOP READ NOP NOP NOP NOP NOP NOP NOP

NOTES:

1. BL8, RL = 5 (CL = 5, AL = 0)

2. DOUT n (or b) = data-out from column n (or column b).

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. BL8 setting activated by either MR0[A1:0 = 00] or MR0[A1:0 = 01] and A12 = 1 during READ commands at T0 and T4.

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP NOP NOP

tCCD

Notes 3

Notes 4

Bank,

Col n

Bank,

Col b

Dout

n+1

Dout

n+2

Dout

n+3

Dout

n+4

Dout

n+5

Dout

n+6

Dout

n+7

Dout

b+1

Dout

b+2

Dout

b+3

Dout

b+4

Dout

b+5

Dout

b+6

Dout

b+7

tRPST

tRPRE

RL = 5 RL = 5

Don't CareTRANSITIONING DATA

Notes 2

DQS, DQS#

ADDRESS

COMMAND

Figure 30. Nonconsecutive READ (BL8) to READ (BL8)

NOPREAD NOP NOP NOP READ NOP NOP NOP NOP NOP NOP

NOTES:

1. BL8, RL = 5 (CL = 5, AL = 0), tCCD=5

2. DOUT n (or b) = data-out from column n (or column b)

3. NOP commands are shown for ease of illustration; other commands may be valid at these times

4. BL8 setting activated by either MR0[A1:0 = 00] or MR0[A1:0 = 01] and A12 = 1 during READ commands at T0 and T4

5. DQS-DQS# is held logic low at T9

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP NOP NOP

tCCD = 5

Notes 3

Notes 4

Bank,

Col n

Bank,

Col b

tRPST

tRPRE

RL = 5 RL = 5

Don't CareTRANSITIONING DATA

Notes 2

DQS, DQS#

ADDRESS

COMMAND

Notes 5

Figure 31. READ (BL4) to READ (BL4)

NOPREAD NOP NOP READ NOP NOP NOP NOP NOP NOP NOP

NOTES:

1. BC4, RL = 5 (CL = 5, AL = 0)

2. DOUT n (or b) = data-out from column n (or column b).

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. BC4 setting activated by either MR0[A1:0 = 10] or MR0[A1:0 = 01] and A12 = 0 during READ commands at T0 and T4.

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP NOP NOP

tCCD

Notes 3

Notes 4

Bank,

Col n

Bank,

Col b

Dout

n+1

Dout

n+2

Dout

n+3

Dout

b+1

Dout

b+2

Dout

b+3

tRPRE

RL = 5

Don't CareTRANSITIONING DATA

Notes 2

DQS, DQS#

ADDRESS

COMMAND

tRPST tRPST

tRPRE

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Figure 32. READ (BL8) to WRITE (BL8)

NOPREAD NOP NOP NOP READ NOP NOP NOP NOP NOP NOP

NOTES:

1. BL8, RL = 5 (CL = 5, AL = 0), tCCD=5

2. DOUT n (or b) = data-out from column n (or column b)

3. NOP commands are shown for ease of illustration; other commands may be valid at these times

4. BL8 setting activated by either MR0[A1:0 = 00] or MR0[A1:0 = 01] and A12 = 1 during READ commands at T0 and T4

5. DQS-DQS# is held logic low at T9

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP NOP NOP

tCCD = 5

Notes 3

Notes 4

Bank,

Col n

Bank,

Col b

tRPST

tRPRE

RL = 5 RL = 5

Don't CareTRANSITIONING DATA

Notes 2

DQS, DQS#

ADDRESS

COMMAND

Notes 5

Figure 33. READ (BL4) to WRITE (BL4) OTF

NOPREAD NOP NOP WRITE NOP NOP NOP NOP NOP NOP NOP

NOTES:

1. BC4, RL = 5 (CL = 5, AL = 0), WL = 5 (CWL = 5, AL = 0)

2. DOUT n = dat a - out from column, DIN b = data-in from column b.

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. BC4 setting activated by MR0[A1:0 = 01] and A12 = 0 during READ command at T0 and WRITE command at T4.

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP NOP NOP

READ to WRITE Command Delay = RL + tCCD/2 + 2tCK - WL

Notes 3

Notes 4

Bank,

Col n

Bank,

Col b

Dout

n+1

Dout

n+2

Dout

n+3

Din

b+1

Din

b+2

Din

b+3

tRPRE

RL = 5 WL = 5

Don't CareTRANSITIONING DATA

Notes 2

DQS, DQS#

ADDRESS

COMMAND

tRPST tWPRE

T15

NOP

tWPST

4 clocks

tWR

tWTR

Figure 34. READ (BL8) to READ (BL4) OTF

NOPREAD NOP NOP READ NOP NOP NOP NOP NOP NOP NOP

NOTES:

1. RL = 5 (CL = 5, AL = 0)

2. DOUT n (or b) = data-out from column n (or column b).

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. BL8 setting activated by MR0[A1:0 = 01] and A12 = 1 during READ command at T0.

BC4 setting activated by MR0[A1:0 = 01] and A12 = 0 during READ command at T4.

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP NOP NOP

tCCD

Notes 3

Notes 4

Bank,

Col n

Bank,

Col b

Dout

n+1

Dout

n+2

Dout

n+3

Dout

b+1

Dout

b+2

Dout

b+3

tRPRE

RL = 5

Don't CareTRANSITIONING DATA

Notes 2

DQS, DQS#

ADDRESS

COMMAND

tRPST

Dout

n+4

Dout

n+5

Dout

n+6

Dout

n+7

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Figure 35. READ (BL4) to READ (BL8) OTF

NOPREAD NOP NOP READ NOP NOP NOP NOP NOP NOP NOP

NOTES:

1. RL = 5 (CL = 5, AL = 0)

2. DOUT n (or b) = data-out from column n (or column b).

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. BC4 setting activated by MR0[A1:0 = 01] and A12 = 0 during READ command at T0.

BL8 setting activated by MR0[A1:0 = 01] and A12 = 1 during READ command at T4.

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP NOP NOP

tCCD

Notes 3

Notes 4

Bank,

Col n

Bank,

Col b

Dout

n+1

Dout

n+2

Dout

n+3

Dout

b+4

Dout

b+5

Dout

b+6

Dout

b+7

tRPRE

RL = 5

Don't CareTRANSITIONING DATA

Notes 2

DQS, DQS#

ADDRESS

COMMAND

tRPST

Dout

b+1

Dout

b+2

Dout

b+3

tRPST tRPRE

Figure 36. READ (BC4) to WRITE (BL8) OTF

NOPREAD NOP NOP WRITE NOP NOP NOP NOP NOP NOP NOP

NOTES:

1. BC4, RL = 5 (CL = 5, AL = 0), WL = 5 (CWL = 5, AL = 0)

2. DOUT n = dat a - out from column, DIN b = data-in from column b.

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. BC4 setting activated by MR0[A1:0 = 01] and A12 = 0 during READ command at T0 and WRITE command at T4.

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP NOP NOP

READ to WRITE Command Delay = RL + tCCD/2 + 2tCK - WL

Notes 3

Notes 4

Bank,

Col n

Bank,

Col b

Dout

n+1

Dout

n+2

Dout

n+3

Din

b+1

Din

b+2

Din

b+3

tRPRE

RL = 5 WL = 5

Don't CareTRANSITIONING DATA

Notes 2

DQS, DQS#

ADDRESS

COMMAND

tRPST tWPRE

T15

NOP

tWPST

4 clocks

tWR

tWTR

Din

b+4

Din

b+5

Din

b+6

Din

b+7

Figure 37. READ (BL8) to WRITE (BL4) OTF

NOPREAD NOP NOP NOP NOP WRITE NOP NOP NOP NOP NOP

NOTES:

1. RL = 5 (CL = 5, AL = 0), WL = 5 (CWL= 5, AL = 0)

2. DOUT n = data-out from colu m n , DI N b = da t a - in from column b.

3. NOP commands are shown for ease of illustrati on; ot her commands may be valid at these times.

4. BL8 setting activated by MR0[A 1: 0 = 01] and A 12 = 1 duri ng READ command at T0.

BC4 setting activated by MR0[A 1: 0 = 01] and A1 2 = 0 duri ng WR ITE command at T6.

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP NOP NOP

READ to WRITE Command Delay = RL + tCCD + 2tCK - WL

Notes 3

Notes 4

Bank,

Col n

Bank,

Col b

Dout

n+1

Dout

n+2

Dout

n+3

Din

b+1

Din

b+2

Din

b+3

tRPRE

RL = 5 WL = 5

Don't CareTRANSITIONING DATA

Notes 2

DQS, DQS#

ADDRESS

COMMAND

tRPST tWPRE

T15

NOP

tWPST

Dout

n+4

Dout

n+5

Dout

n+6

Dout

n+7

4 clocks

tWR

tWTR

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Figure 38. READ to PRECHARGE, RL = 5, AL = 0, CL = 5, tRTP = 4, tRP = 5

READNOP NOP NOP NOP PRE NOP NOP NOP NOP ACT NOP

NOTES:

1. RL = 5 (CL = 5, AL = 0)

2. DOUT n = data-out fro m colum n n.

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. The example assumes tRAS.MIN is satisfied at Precharge command time (T5) and t hat tRC. M IN is satisfi ed at the next Active command time (T10).

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP NOP NOP

RL = AL + CL

Bank a,

(or all)

Bank a,

Row b

n+1

n+2

n+3

Don't CareTR ANSITIONING DAT A

T15

NOP

tRP

tRTP

Bank a,

Col n

DQ DO

n+1

n+2

n+3

BL4 Operation:

BL8 Operation:

n+4

n+5

n+6

n+7

DQS, DQS#

ADDRESS

COMMAND

Figure 39. READ to PRECHARGE, RL = 8, AL = CL-2, CL = 5, tRTP = 6, tRP = 5

READNOP NOP NOP NOP NOP NOP NOP NOP NOP PRE NOP

NOTES:

1. RL = 8 (CL = 5, AL = CL - 2)

2. DOUT n = data-out fro m colum n n.

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. The example assumes tRAS.MIN is satisfied at Precharge command time (T10) and t hat tRC. M IN is satis fied at the next Active c ommand time (T15).

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP NOP NOP

AL = CL - 2 = 3

Bank a,

(or all)

n+1

n+2

n+3

Don't CareTR ANSITIONING DAT A

T15

ACT

tRTP

Bank a,

Col n

DQ DO

n+1

n+2

n+3

BL4 Operation:

BL8 Operation:

n+4

n+5

n+6

n+7

Bank a,

Row b

CL = 5

tRP

DQS, DQS#

ADDRESS

COMMAND

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Figure 40. Write Timing Definition and parameters

NOPWRITE NOP NOP NOP NOP NOP NOP NOP NOP NOP

NOTES:

1. BL8, WL = 5 (AL = 0, CWL = 5)

2. DIN n = data-in from column n.

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. BL8 setting activated by either MR0[A1:0 = 00] or MR0[A1:0 = 01] and A12 = 1 during WRITE command at T0.

5. tDQSS must be met at each rising clock edge.

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10

CK#

WL = AL + CWL

Din

n+2

Din

n+3

Don't CareTRANSITIONING DATA

Bank

Col n

Notes 3

Notes 4

Notes 2

tDQSS(min) tWPRE(min)

tDQSH(min) tDQSL

tDQSS tDSH

tDQSH tDQSL tDQSH tDQSL tDQSH tDQSL tDQSH tDQSL(min)

tDSH tDSH tWPST(min)

tDSS tDSS tDSS tDSS tDSS

Din

n+4

Din

n+6

Din

n+7

DQ Din

Din

n+2

Din

n+3

Notes 2

tDQSS(nominal) tWPRE(min)

tDQSH(min) tDQSL

tDSH

tDQSH tDQSL tDQSH tDQSL tDQSH tDQSL tDQSH tDQSL(min)

tDSH tDSH tDSH tWPST(min)

tDSS tDSS tDSS tDSS tDSS

Din

n+4

Din

n+6

Din

n+7

tDSH

DQ Din

Din

n+2

Din

n+3

Notes 2

tDQSS(max) tWPRE(min)

tDQSH(min) tDQSL

tDSH

tDQSH tDQSL tDQSH tDQSL tDQSH tDQSL tDQSH tDQSL(min)

tDSH tDSH tDSH tWPST(min)

tDSS tDSS tDSS tDSS tDSS

Din

n+4

Din

n+6

Din

n+7

tDQSS

COMMAND

ADDRESS

DQS, DQS#

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Figure 41. WRITE Burst Operation WL = 5 (AL = 0, CWL = 5, BL8)

NOPWRITE NOP NOP NOP NOP NOP NOP NOP NOP NOP

NOTES:

1. BL8, WL = 5; AL = 0, CWL = 5.

2. DIN n = data-in from column n.

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. BL8 setting activated by either MR0[A1:0 = 00] or MR0[A1:0 = 01] and A12 = 1 during WRITE command at T0.

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10

CK#

WL = AL + CWL

Din

n+1

Din

n+2

Din

n+3

Don't CareTRANSITIONING DATA

tWPRE

Bank,

Col n

Notes 2

Din

n+4

Din

n+5

Din

n+6

Din

n+7

DQS, DQS#

COMMAND

ADDRESS

Notes 3

Notes 4

tWPST

Figure 42. WRITE Burst Operation WL = 9 (AL = CL-1, CWL = 5, BL8)

NOPWRITE NOP NOP NOP NOP NOP NOP NOP NOP NOP

NOTES:

1. BL8, WL = 9; AL = (CL - 1), CL = 5, CWL = 5.

2. DIN n = data-in from column n.

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. BL8 setting activated by either MR0[A1:0 = 00] or MR0[A1:0 = 01] and A12 = 1 during WRITE command at T0.

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10

CK#

AL = 4

Din

n+1

Din

n+2

Din

n+3

Don't CareTRANSITIONING DATA

tWPRE

Bank,

Col n

Notes 2

Notes 3

Notes 4

DQS, DQS#

ADDRESS

COMMAND

CWL = 5

WL = AL + CWL

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Figure 43. WRITE(BC4) to READ (BC4) operation

NOPWRITE NOP NOP NOP NOP NOP NOP NOP NOP READ

NOTES:

1. BC4, WL = 5, RL = 5.

2. DIN n = data-in from column n.

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. BC4 setting activated by MR0[A1:0 = 10] during WRITE command at T0 and READ command at Tn.

5. tWTR controls the write to read delay to the same device and starts with the first rising clock edge after the last write data shown at T7.

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 Tn

CK#

DQ Din

Din

n+1

Din

n+2

Din

n+3

Don't CareTRANSITIONING DATA

Bank,

Col n

Notes 2

DQS, DQS#

COMMAND

ADDRESS

Notes 3

Notes 4

tWPST

tWTR

WL = 5 RL = 5

TIME BREA K

Notes 5

tWPRE

Figure 44. WRITE(BC4) to Precharge Operation

NOPWRITE NOP NOP NOP NOP NOP NOP NOP NOP PRE

NOTES:

1. BC4, WL = 5, RL = 5.

2. DIN n = data-in from column n.

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. BC4 setting activated by MR0[A1:0 = 10] during WRITE command at T0.

5. The write recovery time (tWR) referenced from the first rising clock edge after the last write data shown at T7.

tWR specifies the last burst write cycle until the precharge command can be issued to the same bank .

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 Tn

CK#

DQ Din

Din

n+1

Din

n+2

Din

n+3

Don't CareTRANSITIONING DATA

tWPRE

Bank,

Col n

Notes 2

DQS, DQS#

COMMAND

ADDRESS

Notes 3

Notes 4

tWPST

tWR

WL = 5

TIME BREA K

Notes 5

Figure 45. WRITE(BC4) OTF to Precharge operation

NOPWRITE NOP NOP NOP NOP NOP NOP NOP NOP NOP NOP

NOTES:

1. BC4 OTF, WL = 5 (CWL = 5, AL = 0)

2. DIN n (or b) = data-in from col um n n.

3. NOP commands are shown for ease of illustration ; other commands may be valid at these times.

4. BC4 OTF setting activat ed by MR0[A1:0 = 01] and A12 = 0 during WRITE command at T0.

5. The write recovery time (tWR) starts at the rising cl ock edge T9 (4 clocks from T5).

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

Ta0 Ta1 Ta2

PRE NOP NOP

Din

n+1

Din

n+2

Din

n+3

Don't CareTRANSITIONING DATA

Bank

Col n VALID

4 Clocks tWR

Notes 3

Notes 2

ADDRESS

Notes 4

COMMAND

DQS, DQS#

tWPRE tWPST

TIME BREAK

WL = 5

Notes 5

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Figure 46. WRITE(BC8) to WRITE(BC8)

NOPWRITE NOP NOP WRITE NOP NOP NOP NOP NOP NOP NOP

NOTES:

1. BL8, WL = 5 (CWL = 5, AL = 0)

2. DIN n (or b) = data-in from column n (or column b).

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. BL8 setting activated by either MR0[A1:0 = 00] or MR0[A1:0 = 01] and A12 = 1 during WRITE command at T0 and T4.

5. The write recovery time (tWR) and write timing parameter (tWTR) are referenced from the first rising clock edge after the last write data shown at T13.

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP NOP NOP

Din

n+1

Din

n+2

Din

n+3

Don't CareTRANSITIONING DA TA

Bank

Col n

Bank

Col b

4 Clocks

Notes 3

Notes 2

ADDRESS

Notes 4

COMMAND

DQS, DQS#

tWPRE tWPST

tCCD

Din

n+4

Din

n+5

Din

n+6

Din

n+7

Din

b+1

Din

b+2

Din

b+3

Din

b+4

Din

b+5

Din

b+6

Din

b+7

tWR

tWTR

WL = 5 WL = 5

Figure 47. WRITE(BC4) to WRITE(BC4) OTF

NOPWRITE NOP NOP WRITE NOP NOP NOP NOP NOP NOP NOP

NOTES:

1. BC4, WL = 5 (CWL = 5, AL = 0)

2. DIN n (or b) = data-in from column n (or column b).

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. BC4 setting activated by MR0[A1:0 = 01] and A12 = 0 during WRITE command at T0 and T4.

5. The write recovery time (tWR) and write timing parameter (tWTR) are referenced from the first rising clock edge at T13 (4 clocks from T9).

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP NOP NOP

Din

n+1

Din

n+2

Din

n+3

Don't CareTRANSITIONING DATA

Bank

Col n

Bank

Col b

4 Clocks

Notes 3

Notes 2

ADDRESS

Notes 4

COMMAND

DQS, DQS#

tWPRE tWPST

tCCD

Din

b+1

Din

b+2

Din

b+3

tWR

tWTR

WL = 5 WL = 5

tWPST tWPRE

Figure 48. WRITE(BC8) to READ(BC4,BC8) OTF

NOPWRITE NOP NOP NOP NOP NOP NOP NOP NOP NOP NOP

NOTES:

1. RL = 5 (CL = 5, AL = 0), WL = 5 (CWL = 5, AL = 0)

2. DIN n = data-in from column n; DOUT b = data-out from column b.

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. BL8 setting activated by either MR0[A1 :0 = 00] or MR0[A1:0 = 01] and A12 = 1 during WRITE command at T0.

READ command at T13 can be either BC4 or BL8 depending on MR0[A1:0] and A12 status at T13.

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP READ NOP

Din

n+1

Din

n+2

Din

n+3

Don't CareTRANSITIONING DATA

Bank

Col n

Bank

Col b

Notes 3

Notes 2

ADDRESS

Notes 4

COMMAND

DQS, DQS#

tWPRE

Din

n+4

Din

n+5

Din

n+6

Din

n+7

RL = 5

tWTR

WL = 5

tWPST

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Figure 49. WRITE(BC4) to READ(BC4,BC8) OTF

NOPWRITE NOP NOP NOP NOP NOP NOP NOP NOP NOP NOP

NOTES:

1. RL = 5 (CL = 5, AL = 0), WL = 5 (CWL =5, AL = 0)

2. DIN n = data-in from column n; DOUT b = data-out from column b.

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. BC4 setting activated by MR0[A1:0 = 01] and A12 = 0 during WRITE command at T0.

READ command at T13 can be either BC4 or BL8 depending on A12 status at T13.

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP READ NOP

Din

n+1

Din

n+2

Din

n+3

Don't CareTRANSITIONING DATA

Bank

Col n

Bank

Col b

Notes 3

Notes 2

ADDRESS

Notes 4

COMMAND

DQS, DQS#

tWPRE

RL = 5

tWTR

WL = 5

tWPST

4 Clocks

Figure 50. WRITE(BC4) to READ(BC4)

NOPWRITE NOP NOP NOP NOP NOP NOP NOP NOP NOP READ

NOTES:

1. RL = 5 (CL = 5, AL = 0), WL = 5 (CWL =5, AL = 0)

2. DIN n = data-in from col u m n n; DOUT b = data-out from column b.

3. NOP commands are shown for ease of illustration ; other commands may be valid at these times.

4. BC4 setting activated by MR0[A1:0 = 10].

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP NOP NOP

Din

n+1

Din

n+2

Din

n+3

Don't CareTRANSITIONING DATA

Bank

Col n

Bank

Col b

Notes 3

Notes 2

ADDRESS

Notes 4

COMMAND

DQS, DQS#

tWPRE

RL = 5

tWTR

WL = 5

tWPST

Figure 51. WRITE(BC8) to WRITE(BC4) OTF

NOPWRITE NOP NOP WRITE NOP NOP NOP NOP NOP NOP NOP

NOTES:

1. WL = 5 (CWL = 5, AL = 0)

2. DIN n (or b) = data-in from column n (or column b).

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. BL8 setting activated by MR0[A1:0 = 01] and A12 = 1 during WRITE command at T0.

BC4 setting activate d by MR 0[A1:0 = 01] and A12 = 0 during WRITE command at T4.

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP NOP NOP

Din

n+1

Din

n+2

Din

n+3

Don't CareTRANSITIONING DATA

Bank

Col n

Bank

Col b

Notes 3

Notes 2

ADDRESS

Notes 4

COMMAND

DQS, DQS#

tWPRE

Din

n+4

Din

n+5

Din

n+6

Din

n+7

tWTR

WL = 5

tWPST

tCCD tWR

4 Clocks

WL = 5

Din

b+1

Din

b+2

Din

b+3

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Figure 52. WRITE(BC4) to WRITE(BC8) OTF

NOPWRITE NOP NOP WRITE NOP NOP NOP NOP NOP NOP NOP

NOTES:

1. WL = 5 (CWL = 5, AL = 0)

2. DIN n (or b) = data-in from column n (or column b).

3. NOP commands are shown for ease of illustration; other commands may be valid at these times.

4. BC4 setting activated by MR0[A1:0 = 01] and A12 = 0 during WRITE command at T0.

BL8 setting activated by MR0[A1:0 = 01] and A12 = 1 during WRITE command at T4.

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP NOP NOP

Din

n+1

Din

n+2

Din

n+3

Don't CareTRANSITIONING DATA

Bank

Col n

Bank

Col b

4 Clocks

Notes 3

Notes 2

ADDRESS

Notes 4

COMMAND

DQS, DQS#

tWPRE tWPST

tCCD

Din

b+1

Din

b+2

Din

b+3

tWR

tWTR

WL = 5 WL = 5

tWPST tWPRE

Din

b+4

Din

b+5

Din

b+6

Din

b+7

Figure 53. Refresh Command Timing

NOPREF NOP REF NOP NOP VALID VALID VALID VALID VALID REF

NOTES:

1. Only NOP/DES commands allowed after Refresh command registered until tRFC(m in) expires.

2. Time interval between two Refresh commands may be extended to a maximum of 9 x tREFI.

T0 T1 Ta0 Ta1 Tb0 Tb1 Tb2 Tb3 Tc0

CK#

Tc1 Tc2 Tc3

VALID VALID VALID

Don't CareTRANSITIONING DATA

tRFC (min)

COMMAND

tRFC

tREFI (max. 9 * tREFI)

DRAM must be idle DRAM must be idle

TIME BREAK

Figure 54. Self-Refresh Entry/Exit Timing

CK#

T1 T2 Ta0 Tb0 Tc0 Tc1 Td0 TeoT0

CK tCKSRE

Tf0

tCKESR

tXS

tXSDLL

NOP SRE NOP VALID

NOP

VALID

ODT

CKE

COMMAND

ADDR

tIS

Don't CareTIME BREA K

NOTES:

1. Only NOP or DES command.

2. Valid commands not requir ing a locked DLL.

3. Valid commands requiring a loc ked DLL.

tCKSRX

VALID

tCPDED

tIS

VALID

SRX

Notes 1 Notes 2

VALID

tRP

ODTL

Enter Self

Refresh

Exit Self

Refresh

Notes 3

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Figure 55. Active Power-Down Entry and Exit Timing Diagram

CK#

T1 T2 Ta0 Ta1 Tb0 Tb1 Tc0T0

CKE

NOPVALID NOP NOP NOP NOP VALID

tIS

tIH tIS

tIH

VALID VALID

tCKE

tPD

tCPDED tXP

Enter

Power-Down

Mode

Exit

Power-Down

Mode

ADDRESS

COMMAND

Don't CareTIME BREAK

NOTE:

VALID command at T0 is ACT, NOP, DES or PRE with still one bank remaining

open after completion of the precharge command.

Figure 56. Power-Down Entry after Read and Read with Auto Precharge

NOP

RD or

RDA NOP NOP NOP NOP NOP NOP NOP NOP NOP NOP

T0 T1 Ta0 Ta1 Ta2 Ta3 Ta4 Ta5 Ta6 Ta7 Ta8 Tb0

CK#

Tb1

VALID

Din

b+1

Din

b+2

Din

b+3

Din

b+4

Din

b+5

Din

b+6

Din

b+7

tPD

tIS

RL = AL + CL

Don't CareTRANSITIONING DATA

ADDRESS

CKE

tCPDED

VALID

VALID VALID

COMMAND

DQS, DQS#

DQ BL8

Din

b+1

Din

b+2

Din

b+3

DQ BC4

tRDPDEN

Power - Down

Entry

TIME BREAK

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Figure 57. Power-Dow n Entry after Write wi th Auto Precharge

NOPWRITE NOP NOP NOP NOP NOP NOP NOP NOP NOP NOP

T0 T1 Ta0 Ta1 Ta2 Ta3 Ta4 Ta5 Ta6 Ta7 Tb0 Tb1

CK#

Tb2

NOP

Din

b+1

Din

b+2

Din

b+3

Din

b+4

Din

b+5

Din

b+6

Din

b+7

tIS

WL = AL + CWL

Don't CareTRANSITIONING DATA

CKE

tCPDED

VALID

Bank,

Col n VALID

DQ BL8

Din

b+1

Din

b+2

Din

b+3

DQ BC4

tWRAPDEN

Power - Down

Entry

TIME BREAK

Tc0 Tc1

NOP VALID

A10

tPD

NOTES:

1. WR is programmed through MR0.

Start Internal

Precharge

DQS, DQS#

ADDRESS

COMMAND

Notes 1

Figure 58. Power-Dow n Entry after Write

NOPWRITE NOP NOP NOP NOP NOP NOP NOP NOP NOP NOP

T0 T1 Ta0 Ta1 Ta2 Ta3 Ta4 Ta5 Ta6 Ta7 Tb0 Tb1

CK#

Tb2

NOP

Din

b+1

Din

b+2

Din

b+3

Din

b+4

Din

b+5

Din

b+6

Din

b+7

tWR

tIS

WL = AL + CWL

Don't CareTRANSITIONING DATA

CKE

tCPDED

VALID

Bank,

Col n VALID

DQ BL8

Din

b+1

Din

b+2

Din

b+3

DQ BC4

tWRPDEN

Power - Down

Entry

TIME BREAK

Tc0 Tc1

NOP VALID

A10

tPD

DQS, DQS#

ADDRESS

COMMAND

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Figure 59. Precharge Power-Down (Fast Exit Mode) Entry and Exit

CK#

T1 T2 Ta0 Ta1 Tb0 Tb1 Tc0T0

CKE

NOPVALID NOP NOP NOP NOP VALID

tIS

tIH

VALID VALID

tCKE

tCPDED

Enter

Power-Down

Mode

Exit

Power-Down

Mode

COMMAND

Don't CareTIME BREAK

tPD tXP

Figure 60. Precharge Power-Down (Slow Exit Mode) Entry and Exit

CK#

T1 T2 Ta0 Ta1 Tb0 Tb1 Tc0T0

CKE

NOPVALID NOP NOP NOP NOP VALID

tIS

tIH

VALID VALID

tCKE

tCPDED

Enter

Power-Down

Mode

Exit

Power-Down

Mode

COMMAND

Don't CareTIME BREAK

tPD tXP

Td0

VALID

tXPDLL

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Figure 61. Refresh Command to Power-Down Entry

CK#

T1 T2 T3 Ta0 Ta1T0

CKE

REFVALID NOP NOP VALID

tIS tPD

VALID

tCPDED

Don't CareTIME BREAK

tREFPDEN

NOP

VALIDVALID VALID

ADDRESS

COMMAND

Figure 62. Active Command to Power-Down Entry

CK# T1 T2 T3 Ta0 Ta1T0

CKE

ACTIVE

VALID NOP NOP VALID

tIS tPD

VALID

tCPDED

Don't CareTIME BREAK

tACTPDEN

NOP

VALIDVALID VALID

ADDRESS

COMMAND

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Figure 63. Precharge, Precharge all command to Power-Down Entry

CK#

T1 T2 T3 Ta0 Ta1T0

CKE

PRE or

PREA

VALID NOP NOP VALID

tIS tPD

VALID

tCPDED

Don't CareTIME BREAK

tPREPDEN

NOP

VALIDVALID VALID

ADDRESS

COMMAND

Figure 64. MRS Command to Power-Down Entry

CK#

T1 Ta0 Ta1 Tb0 Tb1T0

CKE

NOPMRS NOP VALID

tIS tPD

VALID

tCPDED

Don't CareTIME BREAK

tMRSPDEN

NOP

VALID VALID

ADDRESS

COMMAND

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Figure 65. Synchronous ODT Timing Example

(AL = 3; CWL = 5; ODTLon = AL + CWL - 2 = 6; ODTLoff = AL + CWL - 2 = 6)

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12

tAON(min)

ODTH4, min

Don't CareTRANSITIONING DATA

ODT

AL = 3

T13 T14

CKE

T15

CWL - 2

ODTLoff = CWL + AL - 2

ODTLon = CWL + AL - 2

DRAM_RTT

tAON(max)

tAOF(min)

tAOF(max)

RTT_NOM

AL = 3

Figure 66. Synchronous ODT example with BL = 4, WL = 7

NOPNOP NOP NOP NOP NOP NOP WRS4 NOP NOP NOP NOP

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP NOP NOP

ODTH4

Don't CareTRANSITIONING DATA

T15

NOP

ODTLoff = WL - 2

DRAM_RTT

ODT

COMMAND

CKE

T16 T17

NOP NOP

ODTH4min

ODTH4

ODTLon = WL - 2 ODTLon = WL - 2

ODTLoff = WL - 2

RTT_NOM

tAOF(min) tAON(max)

tAOF(max) tAON(min)

tAON(max)

tAON(min) tAOF(min)

tAOF(max)

Figure 67. Dynamic ODT Behavior with ODT being asserted before and after the write

NOPNOP NOP NOP WRS4 NOP NOP NOP NOP NOP NOP NOP

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

NOP NOP NOP

Don't CareTRANSITIONING DATA

T15

NOP

ODT

T16 T17

NOP NOP

ODTH4

ODTLon

VALID

RTT

Din

n+1

Din

n+2

Din

n+3

ODTLoff

tADC(min)

tADC(max)

tAON(min)

ODTH4

ODTLcwn4

tAON(max)

RTT_NOM RTT_WR

tADC(min)

tADC(max)

tAOF(min)

tAOF(max)

RTT_NOM

ODTLcnw

NOTES:

Example for BC4 (via MRS or OTF), AL = 0, CWL = 5. ODTH4 applies to first registering ODT high and to the registration of the Write command.

In this example, ODTH4 would be satisfied if ODT went low at T8 (4 clocks after the Write command).

DQS, DQS#

COMMAND

ADDRESS

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Figure 68. Dynamic ODT: Behavior without write command, AL = 0, CWL = 5

VALIDVALID VALID VALID VALID VALID VALID VALID VALID VALID VALID VALID

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

Don't CareTRANSITIONING DATA

ODT

ODTLoff

ODTLon

RTT

tAON(min)

ODTH4

tAON(max)

tADC(min)

tADC(max)

NOTES:

1. ODTH4 is defined from ODT registered high to ODT registered low, so in this example, ODTH4 is satisfied.

2. ODT registered low at T5 would also be legal.

RTT_NOM

DQS, DQS#

ADDRESS

COMMAND

Figure 69. Dynamic ODT: Behavior with ODT pin being asserted together with write

command for a duration of 6 clock cycles

WRS8NOP NOP NOP NOP NOP NOP NOP NOP NOP NOP NOP

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

Don't CareTRANSITIONING DATA

ODT

ODTLoff

ODTLcnw

RTT

tAON(min)

ODTH8

tADC(max)

tAOF(min)

tAOF(max)

NOTES:

Example for BL8 (via MRS or OTF), AL = 0, CWL = 5. In this example, ODTH8 = 6 is exactly satisfied.

RTT_WR

VALID

ODTLon

ODTLcwn8

Din

b+1

Din

b+2

Din

b+3

DQS, DQS#

ADDRESS

COMMAND

Din

b+4

Din

b+5

Din

b+6

Din

b+7

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Figure 70. Dynamic ODT: Behavior with ODT pin being asserted together with write

command for a duration of 6 clock cycles, example for BC4

(via MRS or OTF), AL = 0, CWL = 5.

WRS4NOP NOP NOP NOP NOP NOP NOP NOP NOP NOP NOP

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

Don't CareTRANSITIONING DATA

ODT

ODTLoff

ODTLcnw

RTT

tAON(min)

ODTH4

tADC(max)

tADC(min)

tADC(max)

NOTES:

1. ODTH4 is defined from ODT registered high to ODT registered low, so in this example, ODTH4 is satisfied. TRANSITIONING DON T CARE

2. ODT registered low at T5 would also be legal.

VALID

ODTLon

ODTLcwn4

Din

n+1

Din

n+2

Din

n+3

DQS, DQS#

ADDRESS

COMMAND

RTT_WR

tAOF(min)

tAOF(max)

RTT_NOM

Figure 71. Dynamic ODT: Behavior with ODT pin being asserted together with write

command for a duration of 4 clock cycles

WRS4NOP NOP NOP NOP NOP NOP NOP NOP NOP NOP NOP

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

Don't CareTRANSITIONING DATA

ODT

ODTLoff

ODTLcnw

RTT

tAON(min)

ODTH4

tADC(max)

tAOF(min)

tAOF(max)

NOTES:

Example for BC4 (via MRS or OTF), AL = 0, CWL = 5. In this example, ODTH4 = 4 is exactly satisfied.

VALID

ODTLon

ODTLcwn4

Din

n+1

Din

n+2

Din

n+3

DQS, DQS#

ADDRESS

COMMAND

RTT_WR

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Figure 72. Asynchronous ODT Timings on DDR3 SDRAM with fast ODT transition

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12 T13 T14

Don't CareTRANSITION IN G D AT A

T15 T16 T17

RTT

tAONPD(min)

tAONPD(max)

tIH

tIS

tAOFPD(min)

tAOFPD(max)

CKE

ODT

tIH tIS

RTT

Figure 73. Synchronous to asynchronous transition during Precharge Power Dow n

(with DLL frozen) entry (AL = 0; CWL = 5; tANPD = WL - 1 = 4)

REFNOP NOP NOP NOP NOP NOP NOP NOP

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12

Don't CareTRANSITIONING DATA

RTT

tRFC (min)

tCPDED(min)

CKE

tAOF(min)

tAOF(max)

RTT

ODTLoff

tAOFPD(min)

RTT

ODTLoff + tAOFPD(max)

ODTLoff + tAOFPD(min)

tAOFPD(max)

tAOFPD(min)

PD entry transition period

tAOFPD(max)

RTT

T13 Ta0 Ta1 Ta2 Ta3

tANPD

RTT

COMMAND

Last sync.

ODT

Sync. or

async. ODT

First async.

ODT

TIME BREAK

Figure 74. Synchronous to asynchronous transition after Refresh command

(AL = 0; CWL = 5; tANPD = WL - 1 = 4)

REFNOP NOP NOP NOP NOP NOP NOP NOP

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12

Don't CareTRANSITI ON IN G D AT A

RTT

tRFC (min)

tCPDED(min)

CKE

tAOF(min)

tAOF(max)

RTT

ODTLoff

tAOFPD(min)

RTT

ODTLoff + tAOFPD(max)

ODTLoff + tAOFPD(min)

tAOFPD(max)

tAOFPD(min)

PD entry transition period

tAOFPD(max)

RTT

T13 Ta0 Ta1 Ta2 Ta3

tANPD

RTT

COMMAND

Last sync.

ODT

Sync. or

async. ODT

First async.

ODT

TIME BREAK

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Figure 75. Asynchronous to synchronous transition during Precharge Power Down

(with DLL frozen) exit (CL = 6; AL = CL - 1; CWL = 5; tANPD = WL - 1 = 9)

NOPNOP NOP NOP NOP NOP NOP NOP NOP

T0 T1 T2 Ta0 Ta1 Ta2 Ta3 Ta4 Ta5 Ta6 Tb0 Tb1

CK#

Tb2

Don't CareTRANSITIONING DATA

RTT

tXPDLL

tANPD

CKE

tAOFPD(min)

tAOFPD(max)

tAOFPD(min)

RTT

ODTLoff + tAOF(max)

ODTLoff + tAOF(min)

tAOFPD(max)

tAOF(min)

PD exit transition period

tAOF(max)

RTT

Tc0 Tc1 Tc2 Td0 Td1

RTT

ODTLoff

TIME BREAK

NOPNOP

NOP

COMMAND

Last async.

ODT

Sync. or

async. ODT

First sync.

ODT

Figure 76. Transition period for short CKE cycles, entry and exit period overlapping

(AL = 0, WL = 5, tANPD = WL - 1 = 4)

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11

CK#

T12

tANPD

Don't Care

CKE

T13 T14

CKE

PD exit transition period

NOPREF NOP NOP NOP NOP NOP NOP NOP NOP NOP NOP NOP NOP NOP

tRFC (min)

PD entry transition period

tANPD tXPDLL

short CKE low transition period

COMMAND

tANPD

short CKE high transition period

tXPDLL

TIME BREAK

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Figure 77. 96-Ball Window BGA Package 9x13x1.0mm(max) Outline Drawing Information

PIN A1 INDEX

DETAIL : "A"

Top View Bottom View

Side View

Dimension in inch Dimension in mm

Symbol Min Nom Max Min Nom Max

A -- -- 0.039 -- -- 1.00

A1 0.010 -- 0.016 0.25 -- 0.40

A2 -- -- 0.008 -- -- 0.20

D 0.350 0.354 0.358 8.90 9.00 9.10

E 0.508 0.512 0.516 12.90 13.00 13.10

D1 -- 0.252 -- -- 6.40 --

E1 -- 0.472 -- -- 12.00 --

F -- 0.126 -- -- 3.20 --

e -- 0.031 -- -- 0.80 --

b 0.016 0.018 0.020 0.40 0.45 0.50

D2 -- -- 0.081 -- -- 2.05

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PART NUMBERING SYSTEM

AS4C!

256M16D3A!

12!

DRAM! 12=800MHz! B!=!FBGA! I=Industrial!

(-40°!C~95°!C)!

Indicates!Pb!and!

Halogen!Free!

Alliance Memory, Inc.

511 Taylor Way,

San Carlos, CA 94070

Tel: 650-610-6800

Fax: 650-620-9211

www.alliancememory.com

trademarks or registered trademarks of Alliance. All other brand and product names may be the trademarks of their

respective companies. Alliance reserves the right to make changes to this document and its products at any time

without notice. Alliance assumes no responsibility for any errors that may appear in this document. The data

contained herein represents Alliance's best data and/or estimates at the time of issuance. Alliance reserves the right

to change or correct this data at any time, without notice. If the product described herein is under development,

significant changes to these specifications are possible. The information in this product data sheet is intended to be

general descriptive information for potential customers and users, and is not intended to operate as, or provide, any

guarantee or warrantee to any user or customer. Alliance does not assume any responsibility or liability arising out of

the application or use of any product described herein, and disclaims any express or implied warranties related to the

sale and/or use of Alliance products including liability or warranties related to fitness for a particular purpose,

merchantability, or infringement of any intellectual property rights, except as express agreed to in Alliance's Terms

and Conditions of Sale (which are available from Alliance). All sales of Alliance products are made exclusively

according to Alliance's Terms and Conditions of Sale. The purchase of products from Alliance does not convey a

license under any patent rights, copyrights; mask works rights, trademarks, or any other intellectual property rights of

Alliance or third parties. Alliance does not authorize its products for use as critical components in life-supporting

systems where a malfunction or failure may reasonably be expected to result in significant injury to the user, and the

inclusion of Alliance products in such life-supporting systems implies that the manufacturer assumes all risk of such

use and agrees to indemnify Alliance against all claims arising from such use.

Confidential

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256M16=256MX16

D3=DDR3

A=A die version