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White Electronic Designs

W3E16M64S-XBX

February 2005
Rev. 4

BENEFITS

50%

SPACE

SAVINGS

Reduced part count

Reduced

I/O

count

· 17% I/O Reduction

Reduced trace lengths for lower parasitic
capacitance

Suitable for hi-reliability applications

Laminate interposer for optimum TCE match

Upgradeable to 32M x 64 density
(W3E32M64S-XBX)

GENERAL DESCRIPTION

The 128MByte (1Gb) DDR SDRAM is a high-speed CMOS,
dynamic random-access, memory using 4 chips containing
268,435,456 bits. Each chip is internally confi gured as a
quad-bank DRAM. Each of the chip's 67,108,864-bit banks
is organized as 8,192 rows by 512 columns by 16 bits.

The 128 MB DDR SDRAM uses a double data rate
architecture to achieve high-speed operation. The
double data rate architecture is essentially a 2n-prefetch
architecture with an interface designed to transfer two data
words per clock cycle at the I/O pins. A single read or write
access for the 128MB DDR SDRAM effectively consists
of a single 2n-bit wide, one-clock-cycle data tansfer at the
internal DRAM core and two corresponding n-bit wide,
one-half-clock-cycle data transfers at the I/O pins.

A bidirectional data strobe (DQS) is transmitted externally,
along with data, for use in data capture at the receiver. DQS
is a strobe transmitted by the DDR SDRAM during READs

16Mx64 DDR SDRAM

FEATURES

DDR Data Rate = 200, 250, 266Mbps

Package:

· 219 Plastic Ball Grid Array (PBGA), 21 x 25mm

2.5V ±0.2V core power supply

2.5V I/O (SSTL_2 compatible)

Differential clock inputs (CLK and CLK#)

Commands entered on each positive CLK edge

Internal pipelined double-data-rate (DDR)
architecture; two data accesses per clock cycle

Programmable Burst length: 2,4 or 8

Bidirectional data strobe (DQS) transmitted/
received with data, i.e., source-synchronous data
capture (one per byte)

DQS edge-aligned with data for READs; center-
aligned with data for WRITEs

DLL to align DQ and DQS transitions with CLK

Four internal banks for concurrent operation

Two data mask (DM) pins for masking write data

Programmable

IOL/IOH

option

Auto precharge option

Auto Refresh and Self Refresh Modes

Commercial,

Industrial

and

Military

Temperature

Ranges

Organized as 16M x 64

Weight: W3E16M64S-XBX - 2 grams typical

* This product is subject to change without notice.

TSOP

11.9

22.3

Monolithic Solution

Actual Size

W3E16M64S-XBX

S
A
V

Area

I/O

Count

4 x 265mm2 = 1060mm2

4 x 66 pins = 264 pins

525mm2

50%

219 Balls

17%

W3E16M64S-XBX

White Electronic Designs

TSOP

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W3E16M64S-XBX

February 2005
Rev. 4

FIGURE 1 PIN CONFIGURATION

NOTE: DNU = Do Not Use; to be left unconnected for future upgrades.

NC = Not Connected Internally.

Top View

9 10

11 12 13 14 15 16

DQ15

DQ0

DQ14

DQ1

CAS0#

CS0#

CLK3#

DQ49

DQ62

DQ48

DQ63

DQ31

DQ16

DQ30

DQ17

CLK1

CKE1

CS2#

CAS2#

DQ33

DQ46

DQ32

DQ47

DQ13

DQ2

DQ12

DQ3

DQML0

WE0#

RAS0#

CKE3

CLK3

DQMH3

DQ50

DQ60

DQ51

DQ61

DQ29

DQ18

DQ28

DQ19

DQMH1

CLK1#

CCQ

RAS2#

WE2#

DQML2

DQ35

DQ44

DQ34

DQ45

DQ11

DQ4

DQ10

DQ5

DQ52

DQ57

DQ53

DQ59

DQ27

DQ20

DQ26

DQ21

DQ38

DQ42

DQ36

DQ43

DQ9

DQ6

DQ8

DQ7

DQMH0

CLK0

CKE0

CCQ

CS3#

CAS3#

WE3#

DQ54

DQ56

DQ55

DQ58

DQ25

DQ22

DQ24

DQ23

DQML1

WE1#

CS1#

CKE2

CLK2

DQMH2

DQ39

DQ41

DQ37

DQ40

CCQ

DQSH3

DQSL3

CLK0#

RAS3#

DQML3

CCQ

VREF

RAS1#

CAS1#

CLK2#

DQSL2#

DQSH2

A12

DQSH0

DNU

DQSL1

A10

DNU

BA0

A11

DNU

BA1

CCQ

DQSL0

CCQ

DQSH1

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W3E16M64S-XBX

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0-12

0-1

CLK

CLK#

CKE

CS#

DQML

DQMH

RAS

CAS

0-12

0-1

CLK

CLK#

RAS

CAS

CKE

CS#

DQML

DQMH

RAS

CAS

0-12

0-1

CLK

CLK#

CKE

CS#

DQML

DQMH

RAS

CAS

WE#

RAS#

0-12

0-1

CLK

CLK#

CAS#

WE# RAS# CAS#

CKE

CS#

DQSL

DQSH

CLK

REF

DQSL

DQSH

REF

DQSL

DQSH

REF

DQSL

DQSH

REF

CLK

REF

DQML

DQMH

FIGURE 2 FUNCTIONAL BLOCK DIAGRAM

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Prior to normal operation, the SDRAM must be initialized.
The following sections provide detailed information
covering device initialization, register defi nition, command
descriptions and device operation.

INITIALIZATION

DDR SDRAMs must be powered up and initialized in a
predefi ned manner. Operational procedures other than
those specifi ed may result in undefi ned operation. Power
must fi rst be applied to V

and V

CCQ

simultaneously, and

then to V

REF

(and to the system V

). V

must be applied

after V

CCQ

to avoid device latch-up, which may cause

permanent damage to the device. V

REF

can be applied any

time after V

CCQ

but is expected to be nominally coincident

with V

. Except for CKE, inputs are not recognized as

valid until after V

REF

is applied. CKE is an SSTL_2 input

but will detect an LVCMOS LOW level after V

is applied.

Maintaining an LVCMOS LOW level on CKE during power-
up is required to ensure that the DQ and DQS outputs will
be in the High-Z state, where they will remain until driven
in normal operation (by a read access). After all power
supply and reference voltages are stable, and the clock
is stable, the DDR SDRAM requires a 200

s delay prior

to applying an executable command.

Once the 200

s delay has been satisfi ed, a DESELECT

or NOP command should be applied, and CKE should
be brought HIGH. Following the NOP command, a
PRECHARGE ALL command should be applied. Next a
LOAD MODE REGISTER command should be issued for
the extended mode register (BA1 LOW and BA0 HIGH)
to enable the DLL, followed by another LOAD MODE
REGISTER command to the mode register (BA0/BA1
both LOW) to reset the DLL and to program the operating
parameters. Two-hundred clock cycles are required
between the DLL reset and any READ command. A
PRECHARGE ALL command should then be applied,
placing the device in the all banks idle state.

Once in the idle state, two AUTO REFRESH cycles must
be performed (t

RFC

must be satisfi ed.) Additionally, a LOAD

MODE REGISTER command for the mode register with
the reset DLL bit deactivated (i.e., to program operating
parameters without resetting the DLL) is required.
Following these requirements, the DDR SDRAM is ready
for normal operation.

and by the memory contoller during WRITEs. DQS is edge-
aligned with data for READs and center-aligned with data
for WRITEs. Each chip has two data strobes, one for the
lower byte and one for the upper byte.

The 128MB DDR SDRAM operates from a differential clock
(CLK and CLK#); the crossing of CLK going HIGH and
CLK# going LOW will be referred to as the positive edge
of CLK. Commands (address and control signals) are
registered at every positive edge of CLK. Input data is
registered on both edges of DQS, and output data is
referenced to both edges of DQS, as well as to both
edges of CLK.

Read and write accesses to the DDR SDRAM are burst
oriented; accesses start at a selected location and continue
for a programmed number of locations in a programmed
sequence. Accesses begin 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 accessed. The address bits registered
coincident with the READ or WRITE command are used
to select the bank and the starting column location for the
burst access.

The DDR SDRAM provides for programmable READ
or WRITE burst lengths of 2, 4, or 8 locations. An auto
precharge function may be enabled to provide a self-
timed row precharge that is initiated at the end of the
burst access.

The pipelined, multibank architecture of DDR SDRAMs
allows for concurrent operation, thereby providing high
effective bandwidth by hiding row precharge and activation
time.

An auto refresh mode is provided, along with a power-
saving power-down mode.

FUNCTIONAL DESCRIPTION

Read and write accesses to the DDR SDRAM are burst
oriented; accesses start at a selected location and continue
for a programmed number of locations in a programmed
sequence. Accesses begin 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 accessed (BA0 and BA1 select the bank, A0-12
select the row). The address bits registered coincident
with the READ or WRITE command are used to select the
starting column location for the burst access.

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REGISTER DEFINITION

MODE REGISTER

The Mode Register is used to defi ne the specifi c mode of
operation of the DDR SDRAM. This defi nition includes the
selection of a burst length, a burst type, a CAS latency,
and an operating mode, as shown in Figure 3. The Mode
Register is programmed via the MODE REGISTER SET
command (with BA0 = 0 and BA1 = 0) and will retain
the stored information until it is programmed again or
the device loses power. (Except for bit A8 which is self
clearing).

Reprogramming the mode register will not alter the contents
of the memory, provided it is performed correctly. The Mode
Register must be loaded (reloaded) when all banks are
idle and no bursts are in progress, and the controller must
wait the specifi ed time before initiating the subsequent
operation. Violating either of these requirements will result
in unspecifi ed operation.

Mode register bits A0-A2 specify the burst length, A3
specifi es the type of burst (sequential or interleaved),
A4-A6 specify the CAS latency, and A7-A12 specify the
operating mode.

BURST LENGTH

Read and write accesses to the DDR SDRAM are burst
oriented, with the burst length being programmable,
as shown in Figure 3. The burst length determines
the maximum number of column locations that can be
accessed for a given READ or WRITE command. Burst
lengths of 2, 4 or 8 locations are available for both the
sequential and the interleaved burst types.

Reserved states should not be used, as unknown operation
or incompatibility with future versions may result.

When a READ or WRITE command is issued, a block of
columns equal to the burst length is effectively selected. All
accesses for that burst take place within this block, meaning
that the burst will wrap within the block if a boundary is
reached. The block is uniquely selected by A1-Ai when the
burst length is set to two; by A2-Ai when the burst length
is set to four (where Ai is the most signifi cant column
address for a given confi guration); and by A3-Ai when the
burst length is set to eight. The remaining (least signifi cant)
address bit(s) is (are) used to select the starting location
within the block. The programmed burst length applies to
both READ and WRITE bursts.

BURST TYPE

Accesses within a given burst may be programmed to be
either sequential or interleaved; this is referred to as the
burst type and is selected via bit M3.

The ordering of accesses within a burst is determined by
the burst length, the burst type and the starting column
address, as shown in Table 1.

READ LATENCY

The READ latency is the delay, in clock cycles, between
the registration of a READ command and the availability
of the fi rst bit of output data. The latency can be set to 2
or 2.5 clocks.

If a READ command is registered at clock edge n, and the
latency is m clocks, the data will be available by clock edge
n+m. Table 2 below indicates the operating frequencies at
which each CAS latency setting can be used.

Reserved states should not be used as unknown operation
or incompatibility with future versions may result.

TABLE 2 CAS LATENCY

SPEED

ALLOWABLE OPERATING

FREQUENCY (MHz)

CAS

LATENCY = 2

CAS

LATENCY = 2.5

-200

100

-250

100

125

-266

100

133

OPERATING MODE

The normal operating mode is selected by issuing a MODE
REGISTER SET command with bits A7-A12 each set to
zero, and bits A0-A6 set to the desired values. A DLL reset
is initiated by issuing a MODE REGISTER SET command
with bits A7 and A9-A12 each set to zero, bit A8 set to one,
and bits A0-A6 set to the desired values. Although not
required, JEDEC specifi cations recommend when a LOAD
MODE REGISTER command is issued to reset the DLL, it
should always be followed by a LOAD MODE REGISTER
command to select normal operating mode.

All other combinations of values for A7-A12 are reserved
for future use and/or test modes. Test modes and reserved
states should not be used because unknown operation or
incompatibility with future versions may result.

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EXTENDED MODE REGISTER

The extended mode register controls functions beyond
those controlled by the mode register; these additional
functions are DLL enable/disable, output drive strength,
and QFC#. These functions are controlled via the bits
shown in Figure 5. The extended mode register is
programmed via the LOAD MODE REGISTER command
to the mode register (with BA0 = 1 and BA1 = 0) and
will retain the stored information until it is programmed
again or the device loses power. The enabling of the DLL
should always be followed by a LOAD MODE REGISTER
command to the mode register (BA0/BA1 both LOW) to
reset the DLL.

The extended mode register must be loaded when all
banks are idle and no bursts are in progress, and the
controller must wait the specifi ed time before initiating
any subsequent operation. Violating either of these
requirements could result in unspecifi ed operation.

TABLE 1 BURST DEFINITION

FIGURE 3 MODE REGISTER DEFINITION

M3 = 0

Reserved

M3 = 1

Reserved

Operating Mode

Normal Operation

Normal Operation/Reset DLL

All other states reserved

Valid

Burst Type

Sequential

Interleaved

CAS Latency

Reserved

2.5

Reserved

Burst Length

Burst Length

CAS Latency

Mode Register (Mx)

Address Bus

M6-M0

Operating Mode

* M14 and M13
(BA0 and BA1 must be
"0, 0" to select
the base mode register
(vs. the extended
mode

Reserved

M10

M11

M12

Burst

Length

Starting Column

Address

Order of Accesses Within a Burst

Type = Sequential

Type = In ter leaved

0-1

1-0

0-1-2-3

1-2-3-0

1-0-3-2

2-3-0-1

3-0-1-2

3-2-1-0

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

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

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

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

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

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

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

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

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

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

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

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

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

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

NOTES:
1. For a burst length of two, A1-Ai select two-data-element block; A0 selects the

starting column within the block.

2. For a burst length of four, A2-Ai select four-data-element block; A0-1 select the

starting column within the block.

3. For a burst length of eight, A3-Ai select eight-data-element block; A0-2 select the

starting column within the block.

4. Whenever a boundary of the block is reached within a given sequence above, the

following access wraps within the block.

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DESELECT

The DESELECT function (CS# HiGH) prevents new
commands from being executed by the DDR SDRAM. The
SDRAM is effectively deselected. Operations already in
progress are not affected.

NO OPERATION (NOP)

The NO OPERATION (NOP) command is used to perform
a NOP to the selected DDR SDRAM (CS# is LOW). This
prevents unwanted commands from being registered
during idle or wait states. Operations already in progress
are not affected.

LOAD MODE REGISTER

The Mode Registers are loaded via inputs A0-12. The
LOAD MODE REGISTER command can only be issued
when all banks are idle, and a subsequent executable
command cannot be issued until t

MRD

is met.

COMMAND READ

NOP

CL = 2.5

DON'T CARE

TRANSITIONING DATA

DQS

T0 T1 T2

T2n

T3n

COMMAND READ

NOP

CL = 2

DQS

CLK

CLK#

T0 T1 T2

T2n

T3n

Burst Length = 4 in the cases shown
Shown with nominal t

and nominal t

DSDQ

DATA

CLK

CLK#

OUTPUT DRIVE STRENGTH

The normal full drive strength for all outputs are specifi ed to
be SSTL2, Class II. The DDR SDRAM supports an option
for reduced drive. This option is intended for the support
of the lighter load and/or point-to-point environments. The
selection of the reduced drive strength will alter the DQs
and DQSs from SSTL2, Class II drive strength to a reduced
drive strength, which is approximately 54 percent of the
SSTL2, Class II drive strength.

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 disabled the DLL
for the purpose of debug or evaluation. (When the device
exits self refresh mode, the DLL is enabled automatically.)
Any time the DLL is enabled, 200 clock cycles must occur
before a READ command can be issued.

COMMANDS

The Truth Table provides a quick reference of available
commands. This is followed by a written description of
each command.

FIGURE 4 CAS LATENCY

FIGURE 5 EXTENDED MODE REGISTER

DEFINITION

DLL

Enable

Disable

DLL

Extended Mode
Register (Ex)

Address Bus

Operating Mode

Drive Strength

Normal

Reduced

Operating Mode

Reserved

E1, E0

Valid

E12

E10

E11

1. E14 and E13 must be "0, 1" to select the Extended Mode Register (vs. the base Mode Register)
2. The QFC# function is not supported.

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NOTES:
1. CKE is HIGH for all commands shown except SELF REFRESH.
2. A0-12 defi ne the op-code to be written to the selected Mode Register. BA0, BA1

select either the mode register (0, 0) or the extended mode register (1, 0).

3. A0-12 provide row address, and BA0, BA1 provide bank address.
4. A0-8 provide column address; A10 HIGH enables the auto precharge feature (non

persistent), while A10 LOW disables the auto precharge feature; BA0, BA1 provide
bank address.

5. A10 LOW: BA0, BA1 determine the bank being precharged. A10 HIGH: All banks

precharged and BA0, BA1 are "Don't Care."

6. This command is AUTO REFRESH if CKE is HIGH; SELF REFRESH if CKE is

LOW.

7. Internal refresh counter controls row addressing; all inputs and I/Os are "Don't

Care" except for CKE.

8. Applies only to read bursts with auto precharge disabled; this command is

undefi ned (and should not be used) for READ bursts with auto precharge enabled
and for WRITE bursts.

9. DESELECT and NOP are functionally interchangeable.
10. Used to mask write data; provided coincident with the corresponding data.

ACTIVE

The ACTIVE command is used to open (or activate) a
row in a particular bank for a subsequent access. The
value on the BA0, BA1 inputs selects the bank, and the
address provided on inputs A0-12 selects the row. This row
remains 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.

READ

The READ command is used to initiate a burst read access
to an active row. The value on the BA0, BA1 inputs selects
the bank, and the address provided on inputs A0-8 selects
the starting column location. The value on input A10
determines whether or not AUTO PRECHARGE is used. If
AUTO PRECHARGE is selected, the row being accessed
will be precharged at the end of the READ burst; if AUTO
PRECHARGE is not selected, the row will remain open
for subsequent accesses.

TRUTH TABLE COMMANDS (NOTE 1)

NAME (FUNCTION)

CS#

RAS#

CAS#

WE#

ADDR

DESELECT (NOP) (9)

NO OPERATION (NOP) (9)

ACTIVE (Select bank and activate row) ( 3)

Bank/Row

READ (Select bank and column, and start READ burst) (4)

Bank/Col

WRITE (Select bank and column, and start WRITE burst) (4)

Bank/Col

BURST TERMINATE (8)

PRECHARGE (Deactivate row in bank or banks) ( 5)

Code

AUTO REFRESH or SELF REFRESH (Enter self refresh mode) (6, 7)

LOAD MODE REGISTER (2)

Op-Code

TRUTH TABLE DM OPERATION

NAME (FUNCTION)

DQs

WRITE ENABLE (10)

Valid

WRITE INHIBIT (10)

WRITE

The WRITE command is used to initiate a burst write
access to an active row. The value on the BA0, BA1 inputs
selects the bank, and the address provided on inputs A0-8
selects the starting column location. The value on input A10
determines whether or not AUTO PRECHARGE is used. If
AUTO PRECHARGE is selected, the row being accessed
will be precharged at the end of the WRITE burst; if AUTO
PRECHARGE is not selected, the row will remain open for
subsequent accesses. Input data appearing on the D/Qs
is written to the memory array subject to the DQM input
logic level appearing coincident with the data. If a given
DQM signal is registered LOW, the corresponding data
will be written to memory; if the DQM signal is registered
HIGH, the corresponding data inputs will be ignored, and a
WRITE will not be executed to that byte/column location.

PRECHARGE

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 access
a specifi ed time (t

) after the PRECHARGE command is

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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. Input A10 determines whether one or all
banks are to be precharged, and in the case where only
one bank is to be precharged, inputs BA0, BA1 select the
bank. Otherwise BA0, BA1 are treated as "Don't Care."
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 will
be treated as a NOP if there is no open row in that bank
(idle state), or if the previously open row is already in the
process of precharging.

AUTO PRECHARGE

AUTO PRECHARGE is a feature which performs the same
individual-bank PRECHARGE function described above, but
without requiring an explicit command. This is accomplished
by using A10 to enable AUTO PRECHARGE in conjunction
with a specifi c READ or WRITE command. A precharge of the
bank/row that is addressed with the READ or WRITE command
is automatically performed upon completion of the READ or
WRITE burst. AUTO PRECHARGE is nonpersistent in that it is
either enabled or disabled for each individual READ or WRITE
command. The device supports concurrent auto precharge if the
command to the other bank does not interrupt the data transfer
to the current bank.

AUTO PRECHARGE ensures that the precharge is initiated
at the earliest valid stage within a burst. This "earliest valid
stage" is determined as if an explicit precharge command
was issued at the earliest possible time, without violating
t

RAS

(MIN).The user must not issue another command to

the same bank until the precharge time (t

) is completed.

This is determined as if an explicit PRECHARGE command
was issued at the earliest possible time, without violating
t

RAS

(MIN).

BURST TERMINATE

The BURST TERMINATE command is used to truncate
READ bursts (with auto precharge disabled). The most
recently registered READ command prior to the BURST
TERMINATE command will be truncated. The open page
which the READ burst was terminated from remains open.

AUTO REFRESH

AUTO REFRESH is used during normal operation of the
DDR SDRAM and is analogous to CAS#-BEFORE-RAS#

(CBR) REFRESH in conventional DRAMs. This command
is nonpersistent, so it must be issued each time a refresh
is required.

The addressing is generated by the internal refresh
controller. This makes the address bits "Don't Care" during
an AUTO REFRESH command. Each DDR SDRAM
requires AUTO REFRESH cycles at an average interval
of 7.8125

s (maximum).

To allow for improved efficiency in scheduling and
switching between tasks, some fl exibility in the absolute
refresh interval is provided. A maximum of eight AUTO
REFRESH commands can be posted to any given DDR
SDRAM, meaning that the maximum absolute interval
between any AUTO REFRESH command and the next
AUTO REFRESH command is 9 x 7.8125

s (70.3s).

This maximum absolute interval is to allow future support
for DLL updates internal to the DDR SDRAM to be
restricted to AUTO REFRESH cycles, without allowing
excessive drift in t

between updates.

Although not a JEDEC requirement, to provide for future
functionality features, CKE must be active (High) during
the AUTO REFRESH period. The AUTO REFRESH period
begins when the AUTO REFRESH command is registered
and ends t

RFC

later.

SELF REFRESH*

The SELF REFRESH command can be used to retain
data in the DDR SDRAM, even if the rest of the system
is powered down. When in the self refresh mode, the
DDR SDRAM retains data without external clocking. The
SELF REFRESH command is initiated like an AUTO
REFRESH command except CKE is disabled (LOW).
The DLL is automatically disabled upon entering SELF
REFRESH and is automatically enabled upon exiting SELF
REFRESH (200 clock cycles must then occur before a
READ command can be issued). Input signals except CKE
are "Don't Care" during SELF REFRESH.

The procedure for exiting self refresh requires a sequence
of commands. First, CLK must be stable prior to CKE
going back HIGH. Once CKE is HIGH, the DDR SDRAM
must have NOP commands issued for t

XSNR

, because

time is required for the completion of any internal refresh
in progress.

A simple algorithm for meeting both refresh and DLL
requirements is to apply NOPs for 200 clock cycles before
applying any other command.

* Self refresh available in commercial and industrial temperatures only.

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White Electronic Designs

W3E16M64S-XBX

February 2005
Rev. 4

ABSOLUTE MAXIMUM RATINGS

Parameter

Unit

Voltage on V

, V

CCQ

Supply relative to Vss

-1 to 3.6

Voltage on I/O pins relative to V

-1 to 3.6

Operating Temperature T

(Mil)

-55 to +125

°C

Operating Temperature T

(Ind)

-40 to +85

°C

Storage Temperature, Plastic

-55 to +150

°C

NOTE:
Stress 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 greater than those indicated in the
operational sections of this specifi cation is not implied. Exposure to absolute maximum
rating conditions for extended periods may affect reliability.

CAPACITANCE (NOTE 13)

Parameter

Symbol

Max

Unit

Input Capacitance: CLK

CI1

Addresses, BA0-1 Input Capacitance

Input Capacitance: All other input-only pins

CI2

Input/Output Capacitance: I/Os

CIO

BGA THERMAL RESISTANCE

Description

Symbol

Max

Units

Notes

Junction to Ambient (No Airfl ow)

Theta JA

14.5

°C/W

Junction to Ball

Theta JB

10.0

°C/W

Junction to Case (Top)

Theta JC

5.4

°C/W

NOTE 1:
Refer to PBGA Thermal Resistance Correlation application note at www.wedc.com in the
application notes section for modeling conditions.

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White Electronic Designs

W3E16M64S-XBX

February 2005
Rev. 4

SPECIFICATIONS AND CONDITIONS

(NOTES 1-5, 10, 12, 14)

= +2.5V ±0.2V; -55°C T

+125°C

Max

Parameter/Condition

Symbol

250Mbps
266Mbps 200Mbps

Units

OPERATING CURRENT: One bank; Active-Precharge; t

= t

(MIN); t

= t

(MIN); DQ, DM, and DQS inputs

changing once per clock cyle; Address and control inputs changing once every two clock cycles; (22, 48)

CC0

500

480

OPERATING CURRENT: One bank; Active-Read-Precharge; Burst = 2; t

= t

(MIN); t

= t

(MIN); I

OUT

= 0mA;

Address and control inputs changing once per clock cycle (22, 48)

CC1

680

620

PRECHARGE POWER-DOWN STANDBY CURRENT: All banks idle; Power-down mode; t

= t

(MIN); CKE =

LOW; (23, 32, 50)

CC2P

IDLE STANDBY CURRENT: CS = HIGH; All banks idle; t

= t

(MIN); CKE = HIGH; Address and other control

inputs changing once per clock cycle. V

= V

REF

for DQ, DQS, and DM (51)

CC2F

180

ACTIVE POWER-DOWN STANDBY CURRENT: One bank active; Power-down mode; t

= t

(MIN); CKE = LOW

(23, 32, 50)

CC3P

120

ACTIVE STANDBY CURRENT: CS = HIGH; CKE = HIGH; One bank; Active-Precharge; t

= t

RAS

(MAX); t

= t

(MIN); DQ, DM, and DQS inputs changing twice per clock cycle; Address and other control inputs changing once
per clock cycle (22)

CC3N

200

OPERATING CURRENT: Burst = 2; Reads; Continuous burst; One bank active; Address and control inputs
changing once per clock cycle; t

= t

(MIN); I

OUT

= 0mA (22, 48)

CC4R

740

OPERATING CURRENT: Burst = 2; Writes; Continuous burst; One bank active; Address and control inputs
changing once per clock cycle; t

= t

(MIN); DQ, DM, and DQS inputs changing twice per clock cycle (22)

CC4W

640

AUTO REFRESH CURRENT

= t

(MIN) (27, 50)

CC5

980

= 7.8125µs (27, 50)

CC5A

SELF REFRESH CURRENT: CKE 0.2V

Standard (11)

CC6

OPERATING CURRENT: Four bank interleaving READs (BL=4) with auto precharge, t

(MIN); t

= t

(MIN); Address and control inputs change only during Active READ or WRITE commands. (22, 49)

CC7

1600

DC ELECTRICAL CHARACTERISTICS AND OPERATING CONDITIONS

(NOTES 1, 6)

= +2.5V ±0.2V; -55°C T

+125°C

Parameter/Condition

Symbol

Min

Max

Units

Supply Voltage

2.3

2.7

I/O Supply Voltage

CCQ

2.3

2.7

Input High Voltage: Logic 1; All inputs (21)

REF

- 0.04

REF

+ 0.04

Input Low Voltage: Logic 0; All inputs (21)

-0.3

REF

- 0.15

Input Leakage Current: Any input 0V V

(All other pins not under test = 0V)

-2

µA

Input Leakage Address Current (All other pins not under test = 0V)

-8

µA

Output Leakage Current: I/Os are disabled; 0V V

OUT

-5

µA

Output Levels: Full drive option
High Current (V

OUT

= V

CCQ

- 0.373V, minimum V

REF

, minimum V

)

Low Current (V

OUT

= 0.373V, maximum V

REF

, maximum V

)

-12

Output Levels: Reduced drive option
High Current (V

OUT

= V

CCQ

- 0.763V, minimum V

REF

, minimum V

)

Low Current (V

OUT

= 0.763V, maximum V

REF

, maximum V

)

OHR

-9

OLR

I/O Reference Voltage

REF

0.49 x V

CCQ

0.51 x V

CCQ

I/O Termination Voltage

REF

- 0.04

REF

+ 0.04

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White Electronic Designs

W3E16M64S-XBX

February 2005
Rev. 4

Parameter

Symbol

266 Mbps CL 2.5

200 Mbps CL 2

250 Mbps CL2.5

200 Mbps CL2

200 Mbps CL2.5

150 Mbps CL2

Units

Min

Max

Min

Max

Min

Max

Access window of DQs from CLK/CLK#

-0.75

+0.75

-0.8

+0.8

-0.8

+0.8

CLK high-level width (30)

0.45

0.55 0.45

0.55

0.45

0.55

CLK low-level width (30)

0.45

0.55

0.45

0.55

0.45

0.55

Clock cycle time

CL = 2.5 (45, 52)

(2.5)

7.5

CL = 2 (45, 52)

(2)

DQ and DM input hold time relative to DQS (26, 31)

0.5

0.6

DQ and DM input setup time relative to DQS (26, 31)

0.5

0.6

DQ and DM input pulse width (for each input) (31)

DIPW

1.75

Access window of DQS from CLK/CLK

DQSCK

-0.75

+0.75

-0.8

+0.8 -0.8

+0.8 ns

DQS input high pulse width

DQSH

0.35

DQS input low pulse width

DQSL

0.35

DQS-DQ skew, DQS to last DQ valid, per group, per access (25, 26)

DQSQ

0.5

0.6

Write command to fi rst DQS latching transition

DQSS

0.75

1.25

0.75

1.25

0.75

1.25

DQS falling edge to CLK rising - setup time

DSS

0.2

DQS falling edge from CLK rising - hold time

DSH

0.2

Half clock period (34)

Data-out high-impedance window from CLK/CLK (18, 42)

+0.75

+0.8

Data-out low-impedance window from CLK/CLK (18, 43)

-0.75

-0.8

Address and control input hold time (fast slew rate) (14)

IHF

0.90

1.1

Address and control input setup time (fast slew rate) (14)

ISF

0.90

1.1

Address and control input hold time (slow slew rate) (14)

IHS

1.1

Address and control input setup time (slow slew rate) (14)

ISS

1.1

LOAD MODE REGISTER command cycle time

MRD

DQ-DQS hold, DQS to fi rst DQ to go non-valid, per access (25, 26)

-t

QHS

-t

QHS

-t

QHS

Data hold skew factor

QHS

0.75

ACTIVE to PRECHARGE command (35)

RAS

120,000

ACTIVE to READ with Auto precharge command (46)

RAP

ACTIVE to ACTIVE/AUTO REFRESH command period

AUTO REFRESH command period (50)

RFC

ACTIVE to READ or WRITE delay

RCD

PRECHARGE command period

DQS read preamble (42)

RPRE

0.9

1.1

0.9

1.1

0.9

1.1

DQS read postamble

RPST

0.4 0.6

0.4

0.6

0.4

0.6

ACTIVE bank a to ACTIVE bank b command

RRD

DQS write preamble

WPRE

0.25

DQS write preamble setup time (20, 21)

WPRES

DQS write postamble (19)

WPST

0.4

0.6

0.4

0.6

0.4

0.6

Write recovery time

Internal WRITE to READ command delay

WTR

Data valid output window (25)

- t

DQSQ

- t

DQSQ

- t

DQSQ

REFRESH to REFRESH command interval (23)

REFC

70.3

µs

Average periodic refresh interval (23)

REFI

7.8

µs

Terminating voltage delay to VDD

VTD

Exit SELF REFRESH to non-READ command

XSNR

Exit SELF REFRESH to READ command

XSRD

200

ELECTRICAL CHARACTERISTICS AND RECOMMENDED AC OPERATING CHARACTERISTICS

(Notes 1-5, 14-17, 33)

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White Electronic Designs

W3E16M64S-XBX

February 2005
Rev. 4

NOTES:
1. All voltages referenced to V

2. Tests for AC timing, I

, and electrical AC and DC characteristics may be conducted

at nominal reference/supply voltage levels, but the related specifi cations and device
operation are guaranteed for the full voltage range specifi ed.

3. Outputs measured with equivalent load:

Reference

Point

30pF

Output
(V

OUT

)

4. AC timing and I

tests may use a V

-to-V

swing of up to 1.5V in the test

environment, but input timing is still referenced to V

REF

(or to the crossing point for

CLK/CLK#), and parameter specifi cations are guaranteed for the specifi ed AC input
levels under normal use conditions. The minimum slew rate for the input signals
used to test the device is 1V/ns in the range between V

(AC) and V

(AC).

5. The AC and DC input level specifi cations are as defi ned in the SSTL_2 Standard

(i.e., the receiver will effectively switch as a result of the signal crossing the AC
input level, and will remain in that state as long as the signal does not ring back
above [below] the DC input LOW [HIGH] level).

6. V

REF

is expected to equal V

CCQ/2

of the transmitting device and to track variations in

the DC level of the same. Peak-to-peak noise (noncommon mode) on V

REF

may not

exceed ±2 percent of the DC value. Thus, from V

CCQ/2

, V

REF

is allowed ±25mV for

DC error and an additional ±25mV for AC noise. This measurement is to be taken
at the nearest V

REF

by-pass capacitor.

7. V

is not applied directly to the device. V

is a system supply for signal termination

resistors, is expected to be set equal to V

REF

and must track variations in the DC

level of V

REF

8. V

is the magnitude of the difference between the input level on CLK and the input

level on CLK#.

9. The value of V

and V

are expected to equal V

CCQ/2

of the transmitting device

and must track variations in the DC level of the same.

10. I

is dependent on output loading and cycle rates. Specifi ed values are obtained

with minimum cycle time with the outputs open.

11. Enables on-chip refresh and address counters.
12. I

specifi cations are tested after the device is properly initialized, and is averaged

at the defi ned cycle rate.

13. This parameter is not tested but guaranteed by design. t

= 25°C, f = 1 MHz

14. Command/Address input slew rate = 0.5V/ns. For 266 MHz with slew rates 1V/ns

and faster, tIS and tIH are reduced to 900ps. If the slew rate is less than 0.5V/ns,

timing must be derated: tIS has an additional 50ps per each 100mV/ns reduction in
slew rate from the 500mV/ns. tIH has 0ps added, that is, it remains constant. If the
slew rate exceeds 4.5V/ns, functionality is uncertain.

15. The CLK/CLK# input reference level (for timing referenced to CLK/CLK#) is the

point at which CLK and CLK# cross; the input reference level for signals other than
CLK/CLK# is V

REF

16. Inputs are not recognized as valid until V

REF

stabilizes. Exception: during the period

before V

REF

stabilizes, CKE 0.3 x V

CCQ

is recognized as LOW.

17. The output timing reference level, as measured at the timing reference point

indicated in Note 3, is V

18. t

and t

transitions occur in the same access time windows as valid data

transitions. These parameters are not referenced to a specifi c voltage level, but
specify when the device output is no longer driving (HZ) or begins driving (LZ).

19. The maximum limit for this parameter is not a device limit. The device will operate

with a greater value for this parameter, but system performance (bus turnaround)
will degrade accordingly.

20. This is not a device limit. The device will operate with a negative value, but system

performance could be degraded due to bus turnaround.

21. It is recommended that DQS be valid (HIGH or LOW) on or before the WRITE

command. The case shown (DQS going from High-Z to logic LOW) applies when
no WRITEs were previously in progress on the bus. If a previous WRITE was in
progress, DQS could be HIGH during this time, depending on t

DQSS

22. MIN (t

or t

RFC

) for I

measurements is the smallest multiple of t

that meets

the minimum absolute value for the respective parameter. t

RAS

(MAX) for I

measurements is the largest multiple of t

that meets the maximum absolute value

for t

RAS

23. The refresh period 64ms. This equates to an average refresh rate of 7.8125µs.

However, an AUTO REFRESH command must be asserted at least once every
70.3µs; burst refreshing or posting by the DRAM controller greater than eight
refresh cycles is not allowed.

24. The I/O capacitance per DQS and DQ byte/group will not differ by more than this

maximum amount for any given device.

25. The valid data window is derived by achieving other specifi cations - t

CK/2

DQSQ

, and t

= t

- t

QHS

). The data valid window derates directly porportional

with the clock duty cycle and a practical data valid window can be derived. The
clock is allowed a maximum duty cycle variation of 45/55. Functionality is uncertain
when operating beyond a 45/55 ratio. The data valid window derating curves are
provided below for duty cycles ranging between 50/50 and 45/55.

26. Referenced to each output group: LDQS with DQ0-DQ7; and UDQS with DQ8-

DQ15 of each chip.

27. This limit is actually a nominal value and does not result in a fail value. CKE is

HIGH during REFRESH command period (t

RFC

[MIN]) else CKE is LOW (i.e., during

standby).

160

140

120

100

0.0 0.5 1.0 1.5 2.0 2.5

OUT

(V)

OUT

(mA)

Maximum

Nominal high

Nominal low

Minimum

FIGURE A PULL-DOWN CHARACTERISTICS

FIGURE B PULL-UP CHARACTERISTICS

-20

-40

-60

-80

-100

-120

-140

-160

-180

-200

0.0 0.5 1.0 1.5 2.0 2.5

CCQ -

OUT

(V)

OUT

(mA)

Maximum

Nominal high

Nominal low

Minimum

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W3E16M64S-XBX

February 2005
Rev. 4

28. To maintain a valid level, the transitioning edge of the input must:

a) Sustain a constant slew rate from the current AC level through to the target AC

level, V

(AC) or V

(AC).

b) Reach at least the target AC level.

c) After the AC target level is reached, continue to maintain at least the target DC

level, V

(DC) or V

(DC).

29. The Input capacitance per pin group will not differ by more than this maximum

amount for any given device.

30. CLK and CLK# input slew rate must be 1V/ns (2V/ns differentially).
31. DQ and DM input slew rates must not deviate from DQS by more than 10%. If the

DQ/DM/DQS slew rate is less than 0.5V/ns, timing must be derated: 50ps must be
added to t

and t

for each 100mV/ns reduction in slew rate. If slew rate exceeds

4V/ns, functionality is uncertain.

32. V

must not vary more than 4% if CKE is not active while any bank is active.

33. The clock is allowed up to ±150ps of jitter. Each timing parameter is allowed to vary

by the same amount.

34. t

min is the lesser of t

minimum and t

minimum actually applied to the device

CLK and CLK# inputs, collectively during bank active.

35. READs and WRITEs with auto precharge are not allowed to be issued until

RAS

(MIN) can be satisfi ed prior to the internal precharge command being issued.

36. Any positive glitch must be less than 1/3 of the clock and not more than +400mV or

2.9 volts, whichever is less. Any negative glitch must be less than
1/3 of the clock cycle and not exceed either -300mV or 2.2 volts, whichever is more
positive.

37. Normal Output Drive Curves:

a) The full variation in driver pull-down current from minimum to maximum

process, temperature and voltage will lie within the outer bounding lines of the
V-I curve of Figure A.

b) The variation in driver pull-down current within nominal limits of voltage and

temperature is expected, but not guaranteed, to lie within the inner bounding
lines of the V-I curve of Figure A.

c) The full variation in driver pull-up current from minimum to maximum process,

temperature and voltage will lie within the outer bounding lines of the V-I curve
of Figure B.

d) The variation in driver pull-up current within nominal limits of voltage and

temperature is expected, but not guaranteed, to lie within the inner bounding
lines of the V-I curve of Figure B.

e) The full variation in the ratio of the maximum to minimum pull-up and pull-down

current should be between .71 and 1.4, for device drain-to-source voltages
from 0.1V to 1.0 Volt, and at the same voltage and temperature.

f) The full variation in the ratio of the nominal pull-up to pull-down current should

be unity ±10%, for device drain-to-source voltages from 0.1V to 1.0 Volt.

38. Reduced Output Drive Curves:

a) The full variation in driver pull-down current from minimum to maximum

process, temperature and voltage will lie within the outer bounding lines of the
V-I curve of Figure C.

b) The variation in driver pull-down current within nominal limits of voltage and

temperature is expected, but not guaranteed, to lie within the inner bounding
lines of the V-I curve of Figure C.

c) The full variation in driver pull-up current from minimum to maximum process,

temperature and voltage will lie within the outer bounding lines of the V-I curve
of Figure D.

d) The variation in driver pull-up current within nominal limits of voltage and

temperature is expected, but not guaranteed, to lie within the inner bounding
lines of the V-I curve of Figure D.

e) The full variation in the ratio of the maximum to minimum pull-up and pull-down

current should be between .71 and 1.4, for device drain-to-source voltages
from 0.1V to 1.0 V, and at the same voltage and temperature.

f) The full variation in the ratio of the nominal pull-up to pull-down current should

be unity ±10%, for device drain-to-source voltages from 0.1V to 1.0 V.

39. The voltage levels used are derived from a minimum V

level and the referenced

test load. In practice, the voltage levels obtained from a properly terminated bus will
provide signifi cantly different voltage values.

40. V

overshoot: V

(MAX) = V

CCQ

+1.5V for a pulse width 3ns and the pulse width

can not be greater than 1/3 of the cycle rate.

41. V

and V

CCQ

must track each other.

42. This maximum value is derived from the referenced test load. In practice, the values

obtained in a typical terminated design may refl ect up to 310ps less for t

(MAX)

and the last DVW. t

(MAX) will prevail over t

DQSCK

(MAX) + t

RPST

(MAX) condition.

(MIN) will prevail over t

DQSCK

(MIN) + t

RPRE

(MAX) condition.

43. For slew rates greater than 1V/ns the (LZ) transition will start about 310ps earlier.
44. During initialization, V

CCQ

, V

, and V

REF

must be equal to or less than V

+ 0.3V.

Alternatively, V

may be 1.35V maximum during power up, even if V

CCQ

are 0

volts, provided a minimum of 42 ohms of series resistance is used between the V

supply and the input pin.

45. The current part operates below the slowest JEDEC operating frequency of 83

MHz. As such, future die may not refl ect this option.

46. Reserved for future use.
47. Reserved for future use.
48. Random addressing changing 50% of data changing at every transfer.
49. Random addressing changing 100% of data changing at every transfer.
50. CKE must be active (high) during the entire time a refresh command is executed.

That is, from the time the AUTO REFRESH command is registered, CKE must be
active at each rising clock edge, until t

RFC

has been satisfi ed.

51. I

CC2N

specifi es the DQ, DQS, and DM to be driven to a valid high or low logic level.

CC2Q

is similar to I

CC2F

except I

CC2Q

specifi es the address and control inputs to

remain stable. Although I

CC2F

, I

CC2N

, and I

CC2Q

are similar, I

CC2F

is "worst case."

52. Whenever the operating frequency is altered, not including jitter, the DLL is required

to be reset. This is followed by 200 clock cycles before any READ command.

FIGURE C PULL-DOWN CHARACTERISTICS

0.0 0.5 1.0 1.5 2.0 2.5

OUT

(V)

OUT

(mA)

Maximum

Nominal high

Nominal low

Minimum

FIGURE D PULL-UP CHARACTERISTICS

0.0 0.5 1.0 1.5 2.0 2.5

CCQ -

OUT

(V)

OUT

(mA)

Maximum

Nominal high

Nominal low

Minimum

-10

-20

-30

-40

-50

-60

-70

-80

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