ETC WEDPN8M72VR-XBX

WEDPN8M72VR
WEDPN8M72VR--XBX
8Mx72 Registered Synchronous DR
AM
DRAM
FEA
TURES
FEATURES
GENER
AL DESCRIPTION
GENERAL
! Registered for enhanced performance of bus speeds of
The 64MByte (512Mb) SDRAM is a high-speed CMOS, dynamic random-access ,memory using 5 chips containing
134,217,728 bits. Each chip is internally configured as a
quad-bank DRAM with a synchronous interface. Each of the
chip’s 33,554,432-bit banks is organized as 4,096 rows by
512 columns by 16 bits. The MCP also incorporates two
16-bit universal bus drivers for address and input control
signals.
!
!
!
!
!
!
!
!
!
!
66 MHz and 100 MHz
Package:
• 219 Plastic Ball Grid Array (PBGA), 32 x 25mm
Single 3.3V ±0.3V power supply
Fully Synchronous; all signals registered on positive edge
of system clock cycle
Internal pipelined operation; column address can be
changed every clock cycle
Internal banks for hiding row access/precharge
Programmable Burst length 1,2,4,8 or full page
4096 refresh cycles
Commercial, Industrial and Military Temperature Ranges
Organized as 8M x 72
Weight: WEDPN8M72VR-XBX - 2.5 grams typical
Read and write accesses to the 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, BA1 select the bank; A0-11 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.
BENEFITS
! 48% SPACE SAVINGS
! Reduced part count
! Reduced I/O count
!
!
!
!
The SDRAM provides for programmable READ or WRITE burst
lengths of 1, 2, 4 or 8 locations, or the full page, with a
burst terminate option. An AUTO PRECHARGE function may
be enabled to provide a self-timed row precharge that is
initiated at the end of the burst sequence.
• 40% I/O Reduction
Laminate interposer for optimum TCE match
Glueless connection to memory controller/PCI bridge
Suitable for hi-reliability applications
Upgradeable to 16M x 72 density (contact factory for
information)
The 512Mb SDRAM uses an internal pipelined architecture
to achieve high-speed operation. This architecture is compatible with the 2n rule of prefetch architectures, but it also
allows the column address to be changed on every clock
cycle to achieve a high-speed, fully random access.
Precharging one bank while accessing one of the other three
banks will hide the precharge cycles and provide seamless, high-speed, random-access operation.
* This datasheet describes a product that is subject to change without notice.
The 512Mb SDRAM is designed to operate in 3.3V, lowpower memory systems. An auto refresh mode is provided,
along with a power-saving, power-down mode.
All inputs and outputs are LVTTL compatible. SDRAMs offer
substantial advances in DRAM operating performance, including the ability to synchronously burst data at a high data
rate with automatic column-address generation, the ability
to interleave between internal banks in order to hide
precharge time and the capability to randomly change column addresses on each clock cycle during a burst access.
November 2003 Rev. 4
1
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WEDPN8M72VR
WEDPN8M72VR--XBX
F IG . 1 PIN CONFIGURATION
T OP VIEW
NOTE: DNU = Do Not Use; to be left unconnected for future upgrades.
NC = Not Connected Internally.
DNU*= Pin K16 is reserved for optional CS2 pinout (CS of U4). Contact factory for information.
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2
WEDPN8M72VR
WEDPN8M72VR--XBX
GR
AM
GRAM
FIG. 2 FUNCTIONAL B LOCK DI AAGR
3
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WEDPN8M72VR
WEDPN8M72VR--XBX
FUNCTIONAL DESCRIPTION
The Mode Register is programmed via the LOAD MODE REGISTER command and will retain the stored information until
it is programmed again or the device loses power.
Read and write accesses to the 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, A0-11 select the
row). The address bits (A0-8) registered coincident with
the READ or WRITE command are used to select the starting column location for the burst access.
Mode register bits M0-M2 specify the burst length, M3
specifies the type of burst (sequential or interleaved), M4M6 specify the CAS latency, M7 and M8 specify the operating mode, M9 specifies the WRITE burst mode, and M10
and M11 are reserved for future use.
The Mode Register must be loaded when all banks are idle,
and the controller must wait the specified time before initiating the subsequent operation. Violating either of these
requirements will result in unspecified operation.
Prior to normal operation, the SDRAM must be initialized.
The following sections provide detailed information covering device initialization, register definition, command descriptions and device operation.
BURST LENGTH
Read and write accesses to the 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 1, 2, 4 or 8 locations are
available for both the sequential and the interleaved burst
types, and a full-page burst is available for the sequential
type. The full-page burst is used in conjunction with the
BURST TERMINATE command to generate arbitrary burst
lengths.
INITIALIZA
TION
INITIALIZATION
SDRAMs must be powered up and initialized in a predefined
manner. Operational procedures other than those specified may result in undefined operation. Once power is applied to VDD and VDDQ (simultaneously) and the clock is
stable (stable clock is defined as a signal cycling within timing constraints specified for the clock pin), the SDRAM requires a 100µs delay prior to issuing any command other
than a COMMAND INHIBIT or a NOP. Starting at some point
during this 100µs period and continuing at least through
the end of this period, COMMAND INHIBIT or NOP commands should be applied.
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 A1-8 when the
burst length is set to two; by A2-8 when the burst length is
set to four; and by A3-8 when the burst length is set to
eight. The remaining (least significant) address bit(s) is (are)
used to select the starting location within the block. Fullpage bursts wrap within the page if the boundary is reached.
Once the 100µs delay has been satisfied with at least one COMMAND INHIBIT or NOP command having been applied, a
PRECHARGE command should be applied. All banks must be
precharged, thereby placing the device in the all banks idle state.
Once in the idle state, two AUTO REFRESH cycles must be
performed. After the AUTO REFRESH cycles are complete, the
SDRAM is ready for Mode Register programming. Because the
Mode Register will power up in an unknown state, it should
be loaded prior to applying any operational command.
BURST TYPE
REGISTER DEFINITION
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.
MODE REGISTER
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.
The Mode Register is used to define the specific mode of
operation of the SDRAM. This definition includes the selection of a burst length, a burst type, a CAS latency, an operating mode and a write burst mode, as shown in Figure 3.
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WEDPN8M72VR
WEDPN8M72VR--XBX
T ABLE 1 - BURST DEFINITION
F IG. 3 M ODE REGISTER DEFINITION
Burst
Length
2
4
8
Full
Page
(y)
Starting Column
Address
A0
0
1
A1 A0
0
0
0
1
1
0
1
1
A2 A1 A0
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
n = A0-9/8/7
(location 0-y)
Order of Accesses Within a Burst
Type = Sequential
Type = Interleaved
0-1
1-0
0-1
1-0
0-1-2-3
1-2-3-0
2-3-0-1
3-0-1-2
0-1-2-3
1-0-3-2
2-3-0-1
3-2-1-0
0-1-2-3-4-5-6-7
1-2-3-4-5-6-7-0
2-3-4-5-6-7-0-1
3-4-5-6-7-0-1-2
4-5-6-7-0-1-2-3
5-6-7-0-1-2-3-4
6-7-0-1-2-3-4-5
7-0-1-2-3-4-5-6
Cn, Cn + 1, Cn + 2
Cn + 3, Cn + 4...
…Cn - 1,
Cn…
0-1-2-3-4-5-6-7
1-0-3-2-5-4-7-6
2-3-0-1-6-7-4-5
3-2-1-0-7-6-5-4
4-5-6-7-0-1-2-3
5-4-7-6-1-0-3-2
6-7-4-5-2-3-0-1
7-6-5-4-3-2-1-0
Not Supported
NOTES:
1. For full-page accesses: y = 512.
2. For a burst length of two, A1-8 select the block-of-two burst; A0 selects the
starting column within the block.
3. For a burst length of four, A2-8 select the block-of-four burst; A0-1 select the
starting column within the block.
4. For a burst length of eight, A3-8 select the block-of-eight burst; A0-2 select
the starting column within the block.
5. For a full-page burst, the full row is selected and A0-8 select the starting
column.
6. Whenever a boundary of the block is reached within a given sequence
above, the following access wraps within the block.
7. For a burst length of one, A0-8 select the unique column to be accessed, and
Mode Register bit M3 is ignored.
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WEDPN8M72VR
WEDPN8M72VR--XBX
Y
FIG. 4 CA S LATENC
TENCY
C AS LA
TENC
Y
LATENC
TENCY
Test modes and reserved states should not be used because unknown operation or incompatibility with future
versions may result.
The CAS latency is the delay, in clock cycles, between the
registration of a READ command and the availability of the
first piece of output data. The latency can be set to two or
three clocks.
WRITE BURST MODE
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. The I/Os will start driving as a result of the clock edge
one cycle earlier (n + m - 1), and provided that the relevant
access times are met, the data will be valid by clock edge n
+ m. For example, assuming that the clock cycle time is such
that all relevant access times are met, if a READ command is
registered at T0 and the latency is programmed to two clocks,
the I/Os will start driving after T1 and the data will be valid by
T2. Table 2 below indicates the operating frequencies at
which each CAS latency setting can be used.
When M9 = 0, the burst length programmed via M0-M2
applies to both READ and WRITE bursts; when M9 = 1, the
programmed burst length applies to READ bursts, but write
accesses are single-location (nonburst) accesses.
T ABLE 2 - C A S L ATENC
Y
TENCY
ALLOWABLE OPERATING
FREQUENCY (MHZ)
Reserved states should not be used as unknown operation or incompatibility with future versions may result.
SPEED
CAS
LATENCY = 2
CAS
LATENCY = 3
-100
≤ 66
≤ 100
-66
≤ 50
≤ 66
COMMANDS
OPER
ATING MODE
OPERA
The Truth Table provides a quick reference of available commands. This is followed by a written description of each
command. Three additional Truth Tables appear following
the Operation section; these tables provide current state/
next state information.
The normal operating mode is selected by setting M7and
M8 to zero; the other combinations of values for M7 and M8
are reserved for future use and/or test modes. The programmed burst length applies to both READ and WRITE bursts.
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WEDPN8M72VR
WEDPN8M72VR--XBX
T RUTH TABLE - COMMANDS AND DQM OPER
ATION (N OTE 1)
PERA
NAME (FUNCTION)
CS
RAS
CAS
WE
DQM
ADDR
COMMAND INHIBIT (NOP)
H
X
X
X
X
X
I/Os
X
NO OPERATION (NOP)
L
H
H
H
X
X
X
X
ACTIVE (Select bank and activate row) ( 3)
L
L
H
H
X
Bank/Row
READ (Select bank and column, and start READ burst) (4)
L
H
L
H
L/H 8
Bank/Col
X
WRITE (Select bank and column, and start WRITE burst) (4)
L
H
L
L
L/H 8
Bank/Col
Valid
BURST TERMINATE
L
H
H
L
X
X
Active
PRECHARGE (Deactivate row in bank or banks) ( 5)
L
L
H
L
X
Code
X
AUTO REFRESH or SELF REFRESH (Enter self refresh mode) (6, 7)
L
L
L
H
X
X
X
LOAD MODE REGISTER (2)
L
L
L
L
X
Op-Code
X
Write Enable/Output Enable (8)
–
–
–
–
L
–
Active
Write Inhibit/Output High-Z (8)
–
–
–
–
H
–
High-Z
NOTES:
1. CKE is HIGH for all commands shown except SELF REFRESH.
2. A0-11 define the op-code written to the Mode Register.
3. A0-11 provide row address, and BA0, BA1 determine which bank is made active.
4. A0-8 provide column address; A10 HIGH enables the auto precharge feature (nonpersistent), while A10 LOW disables the auto precharge feature; BA0, BA1
determine which bank is being read from or written to.
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. Activates or deactivates the I/Os during WRITEs (zero-clock delay) and READs (two-clock delay).
LO AD MODE REGISTER
REGISTER FUNCTION TABLE
INPUTS
The Mode Register is loaded via inputs A0-11. See Mode
Register heading in the Register Definition section. The LOAD
MODE REGISTER command can only be issued when all
banks are idle, and a subsequent executable command
cannot be issued until tMRD is met.
OUTPUT
OE
LE
CLK
A
Y
H
X
X
X
Z
L
L
X
L
L
L
L
X
H
H
L
H
I
L
L
L
H
I
H
H
L
H
L or H
X
Y0(1)
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 A0-11 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.
NOTES:
1. Output level before the indicated steady-state input
conditions were established.
COMMAND INHIBIT
The COMMAND INHIBIT function prevents new commands
from being executed by the SDRAM, regardless of whether
the CLK signal is enabled. The SDRAM is effectively deselected. Operations already in progress are not affected.
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
NO OPER
ATION (NOP)
OPERA
The NO OPERATION (NOP) command is used to perform a
NOP to an SDRAM which is selected (CS is LOW). This prevents unwanted commands from being registered during idle
or wait states. Operations already in progress are not affected.
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WEDPN8M72VR
WEDPN8M72VR--XBX
subsequent accesses. Read data appears on the I/Os subject to the logic level on the DQM inputs two clocks earlier.
If a given DQM signal was registered HIGH, the corresponding I/Os will be High-Z two clocks later; if the DQM signal
was registered LOW, the I/Os will provide valid data.
PRECHARGE is nonpersistent in that it is either enabled or
disabled for each individual READ or WRITE command.
AUTO PRECHARGE ensures that the precharge is initiated at
the earliest valid stage within a burst. The user must not issue
another command to the same bank until the precharge time
(tRP) is completed. This is determined as if an explicit
PRECHARGE command was issued at the earliest possible time.
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 I/Os 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.
BURST TERMINA
TE
TERMINATE
The BURST TERMINATE command is used to truncate either
fixed-length or full-page bursts. The most recently registered
READ or WRITE command prior to the BURST TERMINATE
command will be truncated.
AUTO REFRESH
AUTO REFRESH is used during normal operation of the
SDRAM and is analagous 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 128Mb SDRAM requires 4,096
AUTO REFRESH cycles every refresh period (tREF). Providing a distributed AUTO REFRESH command will meet the
refresh requirement and ensure that each row is refreshed.
Alternatively, 4,096 AUTO REFRESH commands can be issued in a burst at the minimum cycle rate (tRC), once every
refresh period (tREF).
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
specified time (tRP) after the PRECHARGE command is issued. 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.
SELF REFRESH*
The SELF REFRESH command can be used to retain data in
the SDRAM, even if the rest of the system is powered down.
When in the self refresh mode, the SDRAM retains data without external clocking. The SELF REFRESH command is initiated like an AUTO REFRESH command except CKE is disabled (LOW). Once the SELF REFRESH command is registered, all the inputs to the SDRAM become “Don’t Care,”
with the exception of CKE, which must remain LOW.
AUTO PRECHARGE
AUTO PRECHARGE is a feature which performs the same
individual-bank PRECHARGE function described above,
without requiring an explicit command. This is accomplished
by using A10 to enable AUTO PRECHARGE in conjunction
with a specific 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, except in the full-page burst
mode, where AUTO PRECHARGE does not apply. AUTO
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Once self refresh mode is engaged, the SDRAM provides
its own internal clocking, causing it to perform its own AUTO
REFRESH cycles. The SDRAM must remain in self refresh
mode for a minimum period equal to tRAS and may remain
in self refresh mode for an indefinite period beyond that.
The procedure for exiting self refresh requires a sequence
of commands. First, CLK must be stable (stable clock is
8
WEDPN8M72VR
WEDPN8M72VR--XBX
defined as a signal cycling within timing constraints specified for the clock pin) prior to CKE going back HIGH. Once
CKE is HIGH, the SDRAM must have NOP commands issued (a minimum of two clocks) for tXSR, because time is
required for the completion of any internal refresh in
progress.
Upon exiting the self refresh mode, AUTO REFRESH commands must be issued as both SELF REFRESH and AUTO
REFRESH utilize the row refresh counter.
* Self refresh available in commercial and industrial temperatures only.
A B SOL
UTE MAXIMUM R ATINGS
SOLUTE
Parameter
Voltage on VDD, VDDQ Supply relative to Vss
Voltage on NC or I/O pins relative to Vss
Operating Temperature TA (Mil)
Operating Temperature TA (Ind)
Storage Temperature, Plastic
-1 to 4.6
-1 to 4.6
-55 to +125
-40 to +85
-55 to +150
C AP
ACIT
ANCE (NOTE 2)
APA
CITANCE
Parameter
Input Capacitance: CLK, OE, LE
Unit
V
V
°C
°C
°C
Symbol
CI1
Max
20
Unit
pF
Addresses, BA0-1 Input Capacitance
CA
8
pF
Input Capacitance: All other input-only pins
CI2
8
pF
Input/Output Capacitance: I/Os
CIO
12
pF
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 specification is not implied.
Exposure to absolute maximum rating conditions for extended periods may
affect reliability.
DC ELECTRIC
AL C HAR
ACTERISTIC
S A ND O PER
ATING CONDITIONS (NOTES 1, 6)
LECTRICAL
HARA
CTERISTICS
PERA
(VCC = +3.3V ±0.3V
A = -55°C TO +125°C)
±0.3V;; TTA
Parameter/Condition
Symbol
Units
Supply Voltage
VCC
Min
3
Input High Voltage: Logic 1; All inputs (21)
VIH
2
VCC + 0.3
V
Input Low Voltage: Logic 0; All inputs (21)
VIL
-0.3
0.8
V
Input Leakage Current: Any input 0V - VIN - VCC (All other pins not under test = 0V)
Output Leakage Current: I/Os are disabled; 0V - VOUT - VCC
Output Levels:
Output High Voltage (IOUT = -4mA)
Output Low Voltage (IOUT = 4mA)
Max
3.6
V
II
-5
5
µA
I OZ
-5
5
µA
VOH
2.4
–
V
VOL
–
0.4
V
ICC SPECIFIC
ATIONS A ND C ONDITIONS (N OTES 1,6,11,13)
PECIFICA
(VCC = +3.3V ±0.3V
A = -55°C TO +125°C)
±0.3V;; TTA
Parameter/Condition
Symbol
Max
Units
Operating Current: Active Mode;
Burst = 2; Read or Write; tRC = tRC (min); CAS latency = 3 (3, 18, 19)
I CC1
750
mA
Standby Current: Active Mode; CKE = HIGH; CS = HIGH;
All banks active after tRCD met; No accesses in progress (3, 12, 19)
I CC3
250
mA
Operating Current: Burst Mode; Continuous burst;
Read or Write; All banks active; CAS latency = 3 (3, 18, 19)
I CC4
750
mA
Self Refresh Current: CKE - 0.2V (Commercial Temperature: 0°C to + 70°C) (27)
I CC7
10
mA
Self Refresh Current: CKE - 0.2V (Industrial Temperature: (-40°C to + 85°C) (27)
I CC7
10
mA
9
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WEDPN8M72VR
WEDPN8M72VR--XBX
E LECTRIC
C OPER
AL CHAR
ACTERISTIC
S AND R ECOMMENDED A
ATING CHAR
ACTERISTIC
S
LECTRICAL
HARA
CTERISTICS
AC
PERA
HARA
CTERISTICS
(NOTES 5, 6, 8, 9, 11)
Parameter
Symbol
-100
Min
Access time from CLK (pos. edge)
-66
Max
Min
Unit
Max
CL = 3
t AC
6
7.5
ns
CL = 2
t AC
6
9
ns
Address hold time
tAH
1
1
ns
Address setup time
tAS
2
2
ns
CLK high-level width
tCH
3
3
ns
CLK low-level width
tCL
3
3
ns
tCK
8
10
ns
Clock cycle time (22)
CL = 3
CL = 2
tCK
12
15
ns
tCKH
1
1
ns
CKE setup time
tCKS
2
2
ns
CS, RAS, CAS, WE, DQM hold time
tCMH
1
1
ns
CS, RAS, CAS, WE, DQM setup time
tCMS
2
2
ns
Data-in hold time
tDH
1
1
ns
Data-in setup time
tDS
2
2
CKE hold time
Data-out high-impedance time
CL = 3 (10)
tHZ
CL = 2 (10)
tHZ
Data-out low-impedance time
6
7
t LZ
1
10
ns
ns
ns
tOH
3
3
Data-out hold time (no load) (26)
tOHN
1.8
1.8
ACTIVE to PRECHARGE command
tRAS
50
ACTIVE to ACTIVE command period
ns
2
Data-out hold time (load)
120,000
ns
8
60
tRC
70
70
ACTIVE to READ or WRITE delay
tRCD
20
30
Refresh period (4,096 rows) – Commercial, Industrial
tREF
64
ns
ns
ns
64
ms
16
ms
Refresh period (4,096 rows) – Military
tREF
AUTO REFRESH period
t RFC
70
90
ns
PRECHARGE command period
tRP
20
30
ns
ACTIVE bank A to ACTIVE bank B command
tRRD
20
20
tT
0.3
Transition time (7)
WRITE recovery time
(23)
16
ns
120,000
tWR
(24)
Exit SELF REFRESH to ACTIVE command
White Electronic Designs Corporation • Phoenix AZ • (602) 437-1520
tXSR
10
1.2
1
ns
1.2
ns
1 CLK + 7ns
1 CLK + 7ns
—
15
15
ns
80
90
ns
WEDPN8M72VR
WEDPN8M72VR--XBX
AC FUNCTIONAL CHAR
ACTERISTIC
S (NOTES 5,6,7,8,9,11)
HARA
CTERISTICS
Parameter/Condition
Symbol
-100
-66
Units
READ/WRITE command to READ/WRITE command (17)
tCCD
1
1
tCK
CKE to clock disable or power-down entry mode (14)
tCKED
1
1
tCK
CKE to clock enable or power-down exit setup mode (14)
tPED
1
1
tCK
DQM to input data delay (17)
tDQD
0
0
tCK
DQM to data mask during WRITEs
tDQM
0
0
tCK
DQM to data high-impedance during READs
tDQZ
2
2
tCK
WRITE command to input data delay (17)
tDWD
0
0
tCK
Data-in to ACTIVE command (15)
t DAL
4
4
tCK
Data-in to PRECHARGE command (16)
tDPL
2
2
tCK
Last data-in to burst STOP command (17)
tBDL
1
1
tCK
Last data-in to new READ/WRITE command (17)
t CDL
1
1
tCK
Last data-in to PRECHARGE command (16)
tRDL
2
2
tCK
LOAD MODE REGISTER command to ACTIVE or REFRESH command (25)
tMRD
2
2
tCK
CL = 3
tROH
3
3
tCK
CL = 2
tROH
2
2
tCK
Data-out to high-impedance from PRECHARGE command (17)
NOTES:
1. All voltages referenced to VSS.
2. This parameter is not tested but guaranteed by design. f = 1 MHz, TA = 25°C.
3. IDD is dependent on output loading and cycle rates. Specified values are
obtained with minimum cycle time and the outputs open.
4. Enables on-chip refresh and address counters.
5. The minimum specifications are used only to indicate cycle time at which
proper operation over the full temperature range is ensured.
6. An initial pause of 100ms is required after power-up, followed by two AUTO
REFRESH commands, before proper device operation is ensured. (VCC must be
powered up simultaneously.) The two AUTO REFRESH command wake-ups
should be repeated any time the tREF refresh requirement is exceeded.
7. AC characteristics assume tT = 1ns.
8. In addition to meeting the transition rate specification, the clock and CKE must
transit between VIH and VIL (or between VIL and VIH) in a monotonic manner.
9. Outputs measured at 1.5V with equivalent load:
17. Required clocks are specified by JEDEC functionality and are not dependent
on any timing parameter.
18. The ICC current will decrease as the CAS latency is reduced. This is due to
the fact that the maximum cycle rate is slower as the CAS latency is reduced.
19. Address transitions average one transition every two clocks.
20. CLK must be toggled a minimum of two times during this period.
21. VIH overshoot: VIH (MAX) = VCC + 2V for a pulse width ≤ 3ns, and the
pulse width cannot be greater than one third of the cycle rate. VIL undershoot: VIL
(MIN) = -2V for a pulse width ≤ 3ns.
22. The clock frequency must remain constant (stable clock is defined as a
signal cycling within timing constraints specified for the clock pin) during access
or precharge states (READ, WRITE, including tWR, and PRECHARGE commands).
CKE may be used to reduce the data rate.
23. Auto precharge mode only. The precharge timing budget (tRP) begins 7.5ns/
7ns after the first clock delay, after the last WRITE is executed.
24. Precharge mode only.
25. JEDEC and PC100 specify three clocks.
26. Parameter guaranteed by design.
27. Self refresh available in commercial and industrial temperatures only.
10. tHZ defines the time at which the output achieves the open circuit
condition; it is not a reference to VOH or VOL. The last valid data element will
meet tOH before going High-Z.
11. AC timing and IDD tests have VIL = 0V and VIH = 3V, with timing referenced
to 1.5V crossover point.
12. Other input signals are allowed to transition no more than once every two
clocks and are otherwise at valid VIH or VIL levels.
13. ICC specifications are tested after the device is properly initialized.
14. Timing actually specified by tCKS; clock(s) specified as a reference only at
minimum cycle rate.
15. Timing actually specified by tWR plus tRP; clock(s) specified as a reference
only at minimum cycle rate.
16. Timing actually specified by tWR.
11
White Electronic Designs Corporation • (602) 437-1520 • www.whiteedc.com
WEDPN8M72VR
WEDPN8M72VR--XBX
P ACK
AGE DIMENSION: 219 P LASTIC B ALL GRID A RRAY (PBGA)
CKA
B OT
TOM VIEW
OTTOM
32.1 (1.264) MAX
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
T
R
P
N
M
L
K
J
H
G
F
E
D
C
B
A
19.05 (0.750)
NOM
1.27 (0.050)
NOM
25.1 (0.988)
MAX
0.61 (0.024) NOM
219 x ∅ 0.762 (0.030) NOM
2.03 (0.080)
MAX
19.05 (0.750) NOM
ALL LINEAR DIMENSIONS ARE MILLIMETERS AND PARENTHETICALLY IN INCHES
O RDERING INFORMA
TION
NFORMATION
WED P N 8M 72 V R - XXX B X
DEVICE GRADE:
M = Military
-55°C to +125°C
I = Industrial
-40°C to +85°C
C = Commercial
0°C to +70°C
PACKAGE:
B = 219 Plastic Ball Grid Array (PBGA)
FREQUENCY (MHz)
100 = 100MHz
66 = 66MHz
IMPROVEMENT MARK:
R = Registered
3.3V Power Supply
CONFIGURATION, 8M x 72
SDRAM
PLASTIC
WHITE ELECTRONIC DESIGNS CORP.
White Electronic Designs Corporation • Phoenix AZ • (602) 437-1520
12