Etron EM669325BG-1H/LG 4m x 32 low power sdram (lpsdram) Datasheet

EtronTech
EM669325
4M x 32 Low Power SDRAM (LPSDRAM)
Preliminary (Rev 0.6 Sep./2003)
Features
• 4096 refresh cycles/64ms
• Single 3.0V, or 3.3V power supply
• Interface: LVTTL
•Package : 90 ball-FBGA, 11x13mm, Lead Free
•
•
•
•
•
Clock rate: 133/125/100 MHz
Fully synchronous operation
Internal pipelined architecture
Four internal banks (1M x 32bit x 4bank)
Programmable Mode
- CAS# Latency: 1, 2 & 3
- Burst Length: 1, 2, 4, 8, or full page
- Burst Type: Sequential & Interleave
- Burst-Read-Single-Write
• Burst stop function
• Individual byte controlled by DQM0-3
• Auto Refresh and Self Refresh
Ordering Information
Part Number
EM669325BG-7.5G
Frequency
(*)
133MHz
(*)
Package
11x13 BGA
125MHz
11x13 BGA
EM669325BG-1H/LG
100MHz
(*) : G indicates Lead free package
11x13 BGA
EM669325BG-8G
(*)
Pin Assignment : Top View
1
2
A
DQ26
DQ24
B
DQ28
C
3
4
5
6
7
8
9
VSS
VDD
DQ23
DQ21
VDDQ
VSSQ
VDDQ
VSSQ
DQ19
VSSQ
DQ27
DQ25
DQ22
DQ20
VDDQ
D
VSSQ
DQ29
DQ30
DQ17
DQ18
VDD1Q
E
VDDQ
DQ31
NC
NC
DQ16
VSSQ
F
VSS
DQM3
A3
A2
DQM2
VDD
G
A4
A5
A6
A10
A0
A1
H
A7
A8
NC
NC
BA1
A11
J
CLK
CKE
A9
BA0
CS#
RAS#
K
DQM1
NC
NC
CAS#
WE#
DQM0
L
VDDQ
DQ8
VSS
VDD
DQ7
VSSQ
M
VSSQ
DQ10
DQ9
DQ6
DQ5
VDDQ
N
VSSQ
DQ12
DQ14
DQ1
DQ3
VDDQ
P
DQ11
VDDQ
VSSQ
VDDQ
VSSQ
DQ4
R
DQ13
DQ15
VSS
VDD
DQ0
DQ2
Etron Technology, Inc.
No. 6, Technology Rd. V, Science-Based Industrial Park, Hsinchu, Taiwan 30077, R.O.C
TEL: (886)-3-5782345
FAX: (886)-3-5778671
Etron Technology, Inc., reserves the right to make changes to its products and specifications without notice.
EtronTech
EM669325
4M x 32 LPSDRAM
Overview
The EM669325 SDRAM is a high-speed CMOS synchronous DRAM containing 128 Mbits. It is
internally configured as a quad 1M x 32 DRAM with a synchronous interface (all signals are registered on the
positive edge of the clock signal, CLK). Each of the 1M x 32 bit banks is organized as 4096 rows by 256
columns by 32 bits. 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 a BankActivate command which is then followed by a Read or Write command.
The EM669325 provides for programmable Read or Write burst lengths of 1, 2, 4, 8, or full page, with a
burst termination 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. The refresh functions, either Auto or Self Refresh are easy
to use.
By having a programmable mode register, the system can choose the most suitable modes to maximize
its performance. These devices are well suited for applications requiring high memory bandwidth.
Block Diagram
Row Decoder
Column
CL K
CLO CK
BUFFER
4096 X 256 X 32
CELL ARRAY
(BANK #0)
Sense
Amplifier
Sense
Amplifier
CO N T R OL
S IG N A L
GE N ER A T OR
Row Decoder
CKE
CS #
RA S#
CA S#
WE#
Decoder
CO M M A ND
DECODER
MODE
R E G IS T E R
4096X 256 X 32
CELL ARRAY
(BANK #1)
Column
Decoder
Column
Decoder
CO LU MN
COUN TER
Row Decoder
A 1 0 /A P
ADDRESS
BUFFER
A0
A9
A10
A11
BA0
BA1
4096 X 256 X 32
CELL ARRAY
(BANK #2)
Sense
Amplifier
REFRESH
COUN TER
Row Decoder
Sense
DQ
BUFFER
DQ 0
│
D Q31
Amplifier
4096 X 256 X 32
CELL ARRAY
(BANK #3)
Column
Decoder
D Q M 0 ~3
Preliminary
2
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Pin Descriptions
Table 1. Pin Details of 4Mx32 LPSDRAM
Symbol Type Description
CLK
Input Clock: CLK is driven by the system clock. All SDRAM input signals are sampled on the
positive edge of CLK. CLK also increments the internal burst counter and controls the
output registers.
CKE
Input Clock Enable: CKE activates(HIGH) and deactivates(LOW) the CLK signal. If CKE goes
low synchronously with clock(set-up and hold time same as other inputs), 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. CKE is synchronous except
after the device enters Power Down and Self Refresh modes, where CKE becomes
asynchronous until exiting the same mode. The input buffers, including CLK, are disabled
during Power Down and Self Refresh modes, providing low standby power.
BA0,
BA1
Input Bank Select: BA0 and BA1 defines to which bank the BankActivate, Read, Write, or
BankPrecharge command is being applied. The bank address BA0 and BA1 is used
latched in mode register set.
A0-A11 Input Address Inputs: A0-A11 are sampled during the BankActivate command (row address A0A11) and Read/Write command (column address A0-A7 with A10 defining Auto Precharge)
to select one location out of the 1M available in the respective bank. During a Precharge
command, A10 is sampled to determine if all banks are to be precharged (A10 = HIGH).
The address inputs also provide the op-code during a Mode Register Set or Special Mode
Register Set command.
CS#
Input Chip Select: CS# enables (sampled LOW) and disables (sampled HIGH) the command
decoder. All commands are masked when CS# is sampled HIGH. CS# provides for external
bank selection on systems with multiple banks. 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 positive edges of CLK. 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 BS is
turned on to the active state. When the WE# is asserted "LOW," the Precharge command is
selected and the bank designated by BS is switched to the idle state after the precharge
operation.
CAS#
Input Column Address Strobe: The CAS# signal
conjunction with the RAS# and WE# signals and
When RAS# is held "HIGH" and CS# is asserted
asserting CAS# "LOW." Then, the Read or Write
"LOW" or "HIGH."
WE#
Input Write Enable: The WE# signal defines the operation commands in conjunction with the
RAS# and CAS# signals and is latched at the positive edges of CLK. The WE# input is
used to select the BankActivate or Precharge command and Read or Write command.
defines the operation commands in
is latched at the positive edges of CLK.
"LOW," the column access is started by
command is selected by asserting WE#
DQM0 - Input Data Input/Output Mask: Data Input Mask: DM0-DM3 are byte specific. Input data is
DQM3
masked when DM is sampled HIGH during a write cycle. DM3 masks DQ31-DQ24, DM2
masks DQ23-DQ16, DM1 masks DQ15-DQ8, and DM0 masks DQ7-DQ0.
DQ0- Input/ Data I/O: The DQ0-31 input and output data are synchronized with the positive edges of
DQ31 Output CLK. The I/Os are byte-maskable during Reads and Writes.
NC
VDDQ
-
No Connect: These pins should be left unconnected.
Supply DQ Power: Provide isolated power to DQs for improved noise immunity.
Preliminary
3
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
VSSQ
Supply DQ Ground: Provide isolated ground to DQs for improved noise immunity.
VDD
Supply Power Supply: +3.0V±0.3V, or +3.3V±0.3V
VSS
Supply Ground
Preliminary
4
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Operation Mode
Fully synchronous operations are performed to latch the commands at the positive edges of CLK.
Table 2 shows the truth table for the operation commands.
Table 2. Truth Table (Note (1), (2) )
Command
State
CKEn-1 CKEn DQM(6) BS0,1 A10 A11, A9-0 CS# RAS# CAS# WE#
Idle(3)
H
X
X
V
Row address
L
L
H
H
BankPrecharge
Any
H
X
X
V
L
X
L
L
H
L
PrechargeAll
Any
H
X
X
X
H
X
L
L
H
L
Column
address
(A0 ~ A7)
L
H
L
L
L
H
L
L
Column
address
(A0 ~ A7)
L
H
L
H
L
H
L
H
L
L
L
L
BankActivate
Write
Active(3)
H
X
X
V
L
Write and AutoPrecharge
Active(3)
H
X
X
V
H
Read
Active(3)
H
X
X
V
L
Read and Autoprecharge
Active(3)
H
X
X
V
H
Mode Register Set
Idle
H
X
X
No-Operation
Any
H
X
X
X
X
X
L
H
H
H
Active(4)
H
X
X
X
X
X
L
H
H
L
Device Deselect
Any
H
X
X
X
X
X
H
X
X
X
AutoRefresh
Idle
H
H
X
X
X
X
L
L
L
H
SelfRefresh Entry
Idle
H
L
X
X
X
X
L
L
L
H
SelfRefresh Exit
Idle
L
H
X
X
X
X
H
X
X
X
L
H
H
H
H
X
X
X
L
H
H
H
H
X
X
X
L
H
H
H
Burst Stop
OP code
(SelfRefresh)
Clock Suspend Mode Entry
Active
Power Down Mode Entry
Any(5)
Clock Suspend Mode Exit
H
H
L
L
X
X
X
X
X
X
X
X
Active
L
H
X
X
X
X
X
X
X
X
Any
L
H
X
X
X
X
H
X
X
X
L
H
H
H
X
X
X
X
Active
H
X
H
X
X
X
X
X
X
Note: 1. V = Valid, X = Don't care, L = Logic low, H = Logic high
2. CKEn signal is input level when commands are provided.
CKEn-1 signal is input level one clock cycle before the commands are provided.
3. These are states of bank designated by BA signal.
4. Device state is 1, 2, 4, 8, and full page burst operation.
5. Power Down Mode can not enter in the burst operation.
When this command is asserted in the burst cycle, device state is clock suspend mode.
6. DQM0-3
X
Power Down Mode Exit
(PowerDown)
Data Write/Output Enable
Active
H
X
L
X
X
X
Data Mask/Output Disable
Preliminary
5
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Commands
1
BankActivate
(RAS# = "L", CAS# = "H", WE# = "H", BA 0,1= Bank, A0-A11 = Row Address)
The BankActivate command activates the idle bank designated by the BA0,1 (Bank Select)
signal. By latching the row address on A0 to A11 at the time of this command, the selected row
access is initiated. The read or write operation in the same bank can occur after a time delay of
tRCD(min.) from the time of bank activation. A subsequent BankActivate command to a different row
in the same bank can only be issued after the previous active row has been precharged (refer to the
following figure). The minimum time interval between successive BankActivate commands to the
same bank is defined by tRC(min.). The SDRAM has four internal banks on the same chip and shares
part of the internal circuitry to reduce chip area; therefore it restricts the back-to-back activation of
the four banks. tRRD(min.) specifies the minimum time required between activating different banks.
After this command is used, the Write command and the Block Write command perform the no mask
write operation.
T0
T1
T2
T3
Tn+3
CLK
Tn+4
Tn+5
Tn+6
..............
ADDRESS
Bank A
Row Addr.
Bank A
Col Addr.
..............
Bank B
Row Addr.
R/W A with
AutoPrecharge
..............
Bank B
Activate
RAS# - RAS# delay time (tRRD)
RAS# - CAS# delay (tRCD)
COM MAND
Bank A
Activate
NOP
NOP
Bank A
Row Addr.
NOP
NOP
Bank A
Activate
RAS# Cycle time (tRC)
AutoPrecharge
Begin
: "H" or "L"
BankActivate Command Cycle (Burst Length = n, CAS# Latency = 3)
2
BankPrecharge command
(RAS# = "L", CAS# = "H", WE# = "L", BA0,1 = Bank, A10 = "L", A0-A9, A11 = Don't care)
The BankPrecharge command precharges the bank disignated by BA0,1 signal. The
precharged bank is switched from the active state to the idle state. This command can be asserted
anytime after tRAS(min.) is satisfied from the BankActivate command in the desired bank. The
maximum time any bank can be active is specified by tRAS(max.). Therefore, the precharge function
must be performed in any active bank within tRAS(max.). At the end of precharge, the precharged
bank is still in the idle state and is ready to be activated again.
3
PrechargeAll command
(RAS# = "L", CAS# = "H", WE# = "L", BA0,1 = Don’t care, A10 = "H", A0-A9, A11 = Don't care)
The PrechargeAll command precharges all the four banks simultaneously and can be issued
even if all banks are not in the active state. All banks are then switched to the idle state.
4
Read command
(RAS# = "H", CAS# = "L", WE# = "H", BA0,1 = Bank, A10 = "L", A0-A7 = Column Address)
The Read command is used to read a burst of data on consecutive clock cycles from an active
row in an active bank. The bank must be active for at least tRCD(min.) before the Read command is
issued. During read bursts, the valid data-out element from the starting column address will be
available following the CAS# latency after the issue of the Read command. Each subsequent dataout element will be valid by the next positive clock edge (refer to the following figure). The DQs go
into high-impedance at the end of the burst unless other command is initiated. The burst length,
burst sequence, and CAS# latency are determined by the mode register which is already
programmed. A full-page burst will continue until terminated (at the end of the page it will wrap to
column 0 and continue).
Preliminary
6
Rev 0.6
Sep. 2003
EtronTech
T0
T1
EM669325
4M x 32 LPSDRAM
T2
T3
T4
T5
T6
T7
NOP
NOP
NOP
NOP
T8
CL K
COMMAND
READ A
NOP
NOP
DOUT A0
CAS# latency=2
tCK2, DQ's
DOUT A1
DOUT A2
DOUT A0
CAS# latency=3
tCK3, DQ's
DOUT A1
NOP
NOP
DOUT A3
DOUT A2
DOUT A3
Burst Read Operation(Burst Length = 4, CAS# Latency = 2, 3)
The read data appears on the DQs subject to the values on the DQM inputs two clocks earlier
(i.e. DQM latency is two clocks for output buffers). A read burst without the auto precharge function
may be interrupted by a subsequent Read or Write command to the same bank or the other active
bank before the end of the burst length. It may be interrupted by a BankPrecharge/ PrechargeAll
command to the same bank too. The interrupt coming from the Read command can occur on any
clock cycle following a previous Read command (refer to the following figure).
T0
T1
T2
T3
T4
T5
T6
NOP
NOP
NOP
NOP
DOUT B2
DOUT B3
T7
T8
CLK
COMMAND
CAS# latency=2
tCK2, DQ's
CAS# latency=3
tCK3, DQ's
READ A
READ B
NOP
DOUT A0
DOUT B0
DOUT A0
DOUT B1
DOUT B0
DOUT B1
DOUT B2
NOP
NOP
DOUT B3
Read Interrupted by a Read (Burst Length = 4, CAS# Latency = 2, 3)
The DQM inputs are used to avoid I/O contention on the DQ pins when the interrupt comes from
a Write command. The DQMs must be asserted (HIGH) at least two clocks prior to the Write
command to suppress data-out on the DQ pins. To guarantee the DQ pins against I/O contention, a
single cycle with high-impedance on the DQ pins must occur between the last read data and the
Write command (refer to the following three figures). If the data output of the burst read occurs at the
second clock of the burst write, the DQMs must be asserted (HIGH) at least one clock prior to the
Write command to avoid internal bus contention.
Preliminary
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Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
T0
T1
T2
T3
NOP
READ A
NOP
T4
T5
T6
T7
T8
NOP
NOP
CLK
DQM
COM MAND
NOP
NOP
DQ's
NOP
WRITE B
DOUT A0
DI NB 0
Must be Hi-Z before
the Write Command
: "H" or "L"
Read to Write Interval (Burst Length
T0
T1
T2
T3
DINB1
DI NB 2
≧ 4, CAS# Latency = 3)
T4
T5
T6
T7
T8
CLK
1 Clk Interval
DQM
COMMAND
NOP
NOP
BANKA
ACTIVATE
READ A
NOP
CAS# latency=2
tCK2, DQ's
WRITE A
NOP
DIN A0
DIN A1
NOP
NOP
DIN A2
DIN A3
: "H" or "L"
Read to Write Interval (Burst Length ≥ 4, CAS# Latency = 2)
T0
T1
T2
T3
T4
T5
T6
T7
T8
CLK
DQM
COMMAND
NOP
NOP
READ A
NOP
NOP
CAS# latency=2
tCK2, DQ's
WRITE B
DIN B0
NOP
DIN B1
NOP
NOP
DIN B2
DIN B3
: "H" or "L"
Read to Write Interval (Burst Length ≥ 4, CAS# Latency = 2)
A read burst without the auto precharge function may be interrupted by a BankPrecharge/
PrechargeAll command to the same bank. The following figure shows the optimum time that
BankPrecharge/ PrechargeAll command is issued in different CAS# latency.
Preliminary
8
Rev 0.6
Sep. 2003
EtronTech
T0
T1
EM669325
4M x 32 LPSDRAM
T2
T3
T4
T5
T6
T7
T8
CLK
Bank,
Col A
ADDRESS
Bank,
Row
Bank(s)
tRP
COMMAND
READ A
NOP
CAS# latency=2
tCK2, DQ's
NOP
DOUT A0
CAS# latency=3
tCK3, DQ's
NOP
Precharge
NOP
DOUT A1
DOUT A2
DOUT A3
DOUT A0
DOUT A1
NOP
DOUT A2
Activate
NOP
DOUT A3
Read to Precharge (CAS# Latency = 2, 3)
5
Read and AutoPrecharge command
(RAS# = "H", CAS# = "L", WE# = "H", BS = Bank, A10 = "H", A0-A7 = Column Address)
The Read and AutoPrecharge command automatically performs the precharge operation after
the read operation. Once this command is given, any subsequent command cannot occur within a
time delay of {tRP(min.) + burst length}. At full-page burst, only the read operation is performed in this
command and the auto precharge function is ignored.
6
Write command
(RAS# = "H", CAS# = "L", WE# = "L", BS = Bank, A10 = "L", A0-A7 = Column Address)
The Write command is used to write a burst of data on consecutive clock cycles from an active
row in an active bank. The bank must be active for at least tRCD(min.) before the Write command is
issued. During write bursts, the first valid data-in element will be registered coincident with the Write
command. Subsequent data elements will be registered on each successive positive clock edge
(refer to the following figure). The DQs remain with high-impedance at the end of the burst unless
another command is initiated. The burst length and burst sequence are determined by the mode
register, which is already programmed. A full-page burst will continue until terminated (at the end of
the page it will wrap to column 0 and continue).
T0
T1
T2
T3
T4
T5
T6
T7
T8
WRITE A
NOP
NOP
NOP
NOP
NOP
NOP
NOP
DIN A0
DIN A1
DIN A2
DIN A3
don't care
CLK
COM MAND
DQ0 - DQ3
NOP
The first data element and the write
are registered on the same clock edge.
Extra data is masked.
Burst Write Operation (Burst Length = 4, CAS# Latency = 1, 2, 3)
A write burst without the AutoPrecharge function may be interrupted by a subsequent Write,
BankPrecharge/PrechargeAll, or Read command before the end of the burst length. An interrupt
coming from Write command can occur on any clock cycle following the previous Write command
(refer to the following figure).
Preliminary
9
Rev 0.6
Sep. 2003
EtronTech
T0
T1
EM669325
4M x 32 LPSDRAM
T2
T3
T4
T5
T6
T7
T8
NOP
NOP
NOP
NOP
NOP
NOP
DIN B1
DIN B2
DIN B3
CLK
NOP
COM M AND
WRITE A
WRITE B
1 Clk Interval
DIN A0
DQ's
DIN B0
Write Interrupted by a Write (Burst Length = 4, CAS# Latency = 1, 2, 3)
The Read command that interrupts a write burst without auto precharge function should be
issued one cycle after the clock edge in which the last data-in element is registered. In order to avoid
data contention, input data must be removed from the DQs at least one clock cycle before the first
read data appears on the outputs (refer to the following figure). Once the Read command is
registered, the data inputs will be ignored and writes will not be executed.
T0
T1
T2
T3
T4
T5
T6
T7
T8
NOP
NOP
NOP
NOP
NOP
DOUT B1
DOUT B2
DOUT B3
DOUT B0
DOUT B1
CLK
COMMAND
NOP
WRITE A
NOP
READ B
CAS# latency=2
tCK2, DQ's
DIN A0
don't care
CAS# latency=3
tCK3, DQ's
DIN A0
don't care
DOUT B0
don't care
DOUT B2
DOUT B3
Input data must be removed from the DQ's at least one clock
cycle before the Read data appears on the outputs to avoid
data contention.
Input data for the write is masked.
Write Interrupted by a Read (Burst Length = 4, CAS# Latency = 2, 3)
The BankPrecharge/PrechargeAll command that interrupts a write burst without the auto
precharge function should be issued m cycles after the clock edge in which the last data-in element
is registered, where m equals tWR/tCK rounded up to the next whole number. In addition, the DQM
signals must be used to mask input data, starting with the clock edge following the last data-in
element and ending with the clock edge on which the BankPrecharge/PrechargeAll command is
entered (refer to the following figure).
T0
T1
T2
T3
T4
T5
T6
CLK
DQM
tRP
COMM AND
WRITE
ADDRESS
BA NK
COL n
Precharge
NOP
NOP
NOP
BANK (S)
Activate
NOP
ROW
tWR
DI N
n
DQ
DIN
n+1
: don't care
Note: The DQMs can remain low in this example if the length of the write burst is 1 or 2.
Write to Precharge
Preliminary
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Rev 0.6
Sep. 2003
EtronTech
7
EM669325
4M x 32 LPSDRAM
Write and AutoPrecharge command (refer to the following figure)
(RAS# = "H", CAS# = "L", WE# = "L", BS = Bank, A10 = "H", A0-A7 = Column Address)
The Write and AutoPrecharge command performs the precharge operation automatically after
the write operation. Once this command is given, any subsequent command can not occur within a
time delay of {(burst length -1) + tWR + tRP(min.)}. At full-page burst, only the write operation is
performed in this command and the auto precharge function is ignored.
8
Mode Register Set command
(RAS# = "L", CAS# = "L", WE# = "L", BS0,1 and A11-A0 = Register Data)
The mode register stores the data for controlling the various operating modes of SDRAM. The
Mode Register Set command programs the values of CAS# latency, Addressing Mode and Burst
Length in the Mode register to make SDRAM useful for a variety of different applications. The default
values of the Mode Register after power-up are undefined; therefore this command must be issued
at the power-up sequence. The state of pins BA0,1 and A11~A0 in the same cycle is the data written
to the mode register. One clock cycle is required to complete the write in the mode register (refer to
the following figure). The contents of the mode register can be changed using the same command
and the clock cycle requirements during operation as long as all banks are in the idle state.
T0
T1
T2
T3
T4
T5
T6
T7
T8
T9
T10
CLK
tCK2
CKE
Clock min.
CS#
RAS#
CAS#
WE#
Address Key
ADDR.
DQM
tRP
DQ
Hi-Z
PrechargeAll
Mode Register
Set Command
Any
Command
Mode Register Set Cycle (CAS# Latency = 2, 3)
Preliminary
11
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Mode Resistor Bitmap
BA1
0
BA0
0
A9
0
1
A6
0
0
0
0
1
A5
0
0
1
1
0
A11
0
A10
0
Length
Burst
Single Bit
A9
W.B.L
A8
A7
A6
TM
A8
0
1
0
A7
0
0
1
A5
A4
CAS Latency
Mode
Normal
Reserved
Reserved
A4
CAS Latency
0
Reserved
1
1 clock
0
2 clocks
1
3 clocks
1
Reserved
All other Reserved
A2
0
0
0
0
1
A3
BT
A3
0
1
A1
0
0
1
1
1
A2
A1
A0
Burst Length
Type
Sequential
Interleave
A0
Burst Length
0
1
1
2
0
4
1
8
1
Full Page (Sequential)
All other Reserved
Burst Definition, Addressing Sequence of Sequential and Interleave Mode
Burst Length
2
4
8
Preliminary
Start Address
A2
A1
A0
X
X
0
X
X
1
X
0
0
X
0
1
X
1
0
X
1
1
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
Sequential
Interleave
0, 1
1, 0
0, 1, 2, 3
1, 2, 3, 0
2, 3, 0, 1
3, 0, 1, 2
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
0, 1
1, 0
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, 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
12
Rev 0.6
Sep. 2003
EtronTech
9
EM669325
4M x 32 LPSDRAM
No-Operation command
(RAS# = "H", CAS# = "H", WE# = "H")
The No-Operation command is used to perform a NOP to the SDRAM which is selected (CS#
is Low). This prevents unwanted commands from being registered during idle or wait states.
10
Burst Stop command
(RAS# = "H", CAS# = "H", WE# = "L")
The Burst Stop command is used to terminate either fixed-length or full-page bursts. This
command is only effective in a read/write burst without the auto precharge function. The terminated
read burst ends after a delay equal to the CAS# latency (refer to the following figure). The
termination of a write burst is shown in the following figure.
T0
T1
T2
T3
NOP
NOP
T4
T5
T6
T7
T8
NOP
NOP
NOP
NOP
CLK
READ A
COMMAND
NOP
Burst Stop
The burst ends after a delay equal to the CAS# latency.
CAS# latency=2
tCK2, DQ's
DOUT A0
CAS# latency=3
tCK3, DQ's
DOUT A1
DOUT A2
DOUT A3
DOUT A0
DOUT A1
DOUT A2
Termination of a Burst Read Operation (Burst Length
T0
T1
T2
T3
T4
NOP
NOP
Burst Stop
DIN A1
DIN A2
don't care
DOUT A3
> 4, CAS# Latency = 2, 3)
T5
T6
T7
T8
NOP
NOP
NOP
NOP
CLK
NOP
COMMAND
CAS# latency= 2, 3
DQ's
WRITE A
DIN A0
Input data for the Write is masked.
Termination of a Burst Write Operation (Burst Length = X, CAS# Latency = 1, 2, 3)
Preliminary
13
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
11
Device Deselect command (CS# = "H")
The Device Deselect command disables the command decoder so that the RAS#, CAS#, WE#
and Address inputs are ignored, regardless of whether the CLK is enabled. This command is similar
to the No Operation command.
12
AutoRefresh command
(RAS# = "L", CAS# = "L", WE# = "H",CKE = "H", BA0,1 = “Don‘t care, A0-A11 = Don't care)
The AutoRefresh command is used during normal operation of the SDRAM and is analogous to
CAS#-before-RAS# (CBR) Refresh in conventional DRAMs. This command is non-persistent, 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 a "don't care" during an AutoRefresh command. The internal
refresh counter increments automatically on every auto refresh cycle to all of the rows. The refresh
operation must be performed 4096 times within 64ms. The time required to complete the auto
refresh operation is specified by tRC(min.). To provide the AutoRefresh command, all banks need to
be in the idle state and the device must not be in power down mode (CKE is high in the previous
cycle). This command must be followed by NOPs until the auto refresh operation is completed. The
precharge time requirement, tRP(min), must be met before successive auto refresh operations are
performed.
13
SelfRefresh Entry command
(RAS# = "L", CAS# = "L", WE# = "H", CKE = "L", A0-A11 = Don't care)
The SelfRefresh is another refresh mode available in the SDRAM. It is the preferred refresh
mode for data retention and low power operation. Once the SelfRefresh command is registered, all
the inputs to the SDRAM become "don't care" with the exception of CKE, which must remain LOW.
The refresh addressing and timing is internally generated to reduce power consumption. The
SDRAM may remain in SelfRefresh mode for an indefinite period. The SelfRefresh mode is exited by
restarting the external clock and then asserting HIGH on CKE (SelfRefresh Exit command).
14 SelfRefresh Exit command
(CKE = "H", CS# = "H" or CKE = "H", RAS# = "H", CAS# = "H", WE# = "H")
This command is used to exit from the SelfRefresh mode. Once this command is registered,
NOP or Device Deselect commands must be issued for tRC(min.) because time is required for the
completion of any bank currently being internally refreshed. If auto refresh cycles in bursts are
performed during normal operation, a burst of 4096 auto refresh cycles should be completed just
prior to entering and just after exiting the SelfRefresh mode.
15
Clock Suspend Mode Entry / PowerDown Mode Entry command (CKE = "L")
When the SDRAM is operating the burst cycle, the internal CLK is suspended(masked) from the
subsequent cycle by issuing this command (asserting CKE "LOW"). The device operation is held
intact while CLK is suspended. On the other hand, when all banks are in the idle state, this command
performs entry into the PowerDown mode. All input and output buffers (except the CKE buffer) are
turned off in the PowerDown mode. The device may not remain in the Clock Suspend or PowerDown
state longer than the refresh period (64ms) since the command does not perform any refresh
operations.
16
Clock Suspend Mode Exit / PowerDown Mode Exit command
When the internal CLK has been suspended, the operation of the internal CLK is reinitiated from
the subsequent cycle by providing this command (asserting CKE "HIGH"). When the device is in the
PowerDown mode, the device exits this mode and all disabled buffers are turned on to the active
state. tPDE(min.) is required when the device exits from the PowerDown mode. Any subsequent
commands can be issued after one clock cycle from the end of this command.
17
Data Write / Output Enable, Data Mask / Output Disable command (DQM = "L", "H")
During a write cycle, the DQM signal functions as a Data Mask and can control every word of
the input data. During a read cycle, the DQM functions as the controller of output buffers. DQM is
also used for device selection, byte selection and bus control in a memory system.
Preliminary
14
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Absolute Maximum Rating
Symbol
VIN, VOUT
VDD, VDDQ
TOPR
Item
Input, Output Voltage
Power Supply Voltage
Operating Temperature
Rating
- 1.0 ~ +4.6
-1.0 ~ +4.6
-25 ~ +85
TSTG
TSOLDER
Storage Temperature
Soldering Temperature (10s)
- 55~ +150
260
PD
IOUT
Power Dissipation
Short Circuit Output Current
1.0
50
Unit
V
V
°C
°C
°C
W
mA
Note: Stress greater than those listed under "Absolute Maximum Ratings" may cause permanent damage to
the device.
Recommended D.C. Operating Conditions (Ta = -25~85°C)
Parameter/ Condition
Symbol
Min
Typ
Max
Unit
Note
VDD
2.7
3.0
3.6
V
1
VDDQ
2.7
3.0
3.6
V
1
Input High (Logic 1) Voltage
VIH
2.0
2.5
VDDQ+0.3
V
1
Input Low (Logic 0) Voltage
VIL
-0.3
0
0.8
V
1
Data Output High (Logic 1) Voltage
VOH
2.4
-
-
V
1,2,4
Data Output High (Logic 1) Voltage
VOL
-
-
0.4
V
1,3,5
1.5
µA
DRAM Core Supply VOLTAGE
I/O Supply Voltage
Input Leakage Current
( 0V VIN VDD, All other pins not under
test = 0V )
≦ ≦
IIL
-1.5
Note:
1
All voltages are referenced to VSS.
2
3
4
5
IOUT = - 2.0mA
IOUT = + 2.0mA
VIH (max) = 5.6V AC. The overshoot voltage duration is
VIL (min) =-2.0V AC. The undershoot voltage duration is
≦ 5ns.
≦ 5ns.
Capacitance (VDD = 2.5V, f = 1MHz, Ta = 25°C)
Symbol
CI
CI/O
Parameter
Min.
Input Capacitance
4
Max.
Unit
5
pF
Input/Output Capacitance
6
8
pF
Note: These parameters are periodically sampled and are not 100% tested.
Preliminary
15
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
D.C. CHARACTERISTICS (Ta = -25~85°C)
Description/Test condition
Operating Current
1 bank
tRC ≥ tRC(min), Outputs Open, Input
operation
signal one transition per one cycle
Precharge Standby Current in power down mode
tCK = 15ns, CKE ≤ VIL(max)
Precharge Standby Current in power down mode
tCK = ∞, CKE ≤ VIL(max)
Precharge Standby Current in non-power down mode
tCK = 15ns, CS# ≥ VIH(min), CKE ≥ VIH
Input signals are changed once during 30ns.
Precharge Standby Current in non-power down mode
tCK = ∞, CLK ≤ VIL(max), CKE ≥ VIH
Active Standby Current in power down mode
CKE ≤ VIL(max), tCK = 15ns
Active Standby Current in power down mode
CKE & CLK ≤ VIL(max), tCK = ∞
Active Standby Current in non-power down mode
CKE ≥ VIH(min), CS# ≥ VIH(min), tCK = 15ns
Active Standby Current in non-power down mode
CKE ≥ VIH(min), CLK ≤ VIL(max), tCK = ∞
Operating Current (Burst mode)
tCK =tCK(min), Outputs Open, Multi-bank interleave
Refresh Current
tRC ≥ TrC(min)
Self Refresh Current
CKE ≤ 0.2V
Preliminary
16
Symbol
- 75/8/1H/1L
Max.
ICC1
150/145/140/130
ICC2P
2
ICC2PS
2
ICC2N
30
ICC2NS
12
ICC3P
6
ICC3PS
6
ICC3N
60
ICC3NS
50
ICC4
220/210/180/170
ICC5
250/240/220/210
ICC6
800
Rev 0.6
Unit
mA
uA
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Electrical Characteristics and Recommended A.C. Operating Conditions
(VDD = 2.7V~3.6V, Ta = -25~85°C) (Note: 1, 2, 3, 4)
Symbol
- 75/8/1H/1L
Min.
Max.
A.C. Parameter
Unit
Note
tRC
Row cycle time( same bank )
65/66/70/84
5
tRCD
RAS# to CAS# delay (same bank)
20/20/20/24
5
tRP
Precharge to refresh / row activate command
(same bank)
20/20/20/24
tRRD
Row activate to row active delay
15/16/20/20
5
ns
5
(different banks)
tRAS
Row activate to percharge time
45/46/50/60
100,000
5
(same bank)
tRDL
Last data in to row precharge
tCK1
Clock cycle time
10
CL* = 1
- /- /- /25
tCK2
CL* = 2
10/10/10/12
tCK3
CL* = 3
7.5/8/10/10
tCH
tCL
Clock high time
2.5/2.7/3/3
Clock low time
2.5/2.7/3/3
tAC1
Access time from CLk
CL* = 1
- /- / -/18
tAC2
(positive edge)
CL* = 2
6/6/6/6
CL* = 3
5.5/5.6/6/6
tAC3
ns
5
ns
6
5
tCCD
CAS# to CAS# Delay time
1
CLK
tOH
Data output hold time
2
5
tLZ
Data output low impedance
1
5
tHZ1
Data output high impedance
CL* = 1
-/- /-/18
tHZ2
CL* = 2
6/6/6/6
tHZ3
CL* = 3
5.5/5.6/6/6
TIS
Data/Address/Control Input set-up time
tIH
Data/Address/Control Input hold time
tREF
Refresh period (4096 refresh cycles)
ns
2.5/2.7/3/3
5
4
6
1
ns
64
6
ms
*CL is CAS# Latency.
Preliminary
17
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Note:
1
Power-up sequence is described in Note 7.
2
A.C. Test Conditions
LVTTL Interface
Reference Level of Output Signals
1.4V/1.4V
Output Load
Reference to the Under Output Load (B)
Input Signal Levels (VIH/VIL)
2.4V/0.4V
Transition Time (Rise and Fall) of Input Signals
1ns
Reference Level of Input Signals
1.4V
3.3V
3.0V
1.4V
1.2kΩ
50Ω
Z0= 5 0 Ω
Output
Output
30pF
30pF
87 0Ω
LVTTL D.C. Test Load (A)
LVTTL A.C. Test Load (B)
3. Transition times are measured between VIH and VIL. Transition(rise and fall) of input signals are in a fixed
slope (1 ns).
4. tHZ defines the time in which the outputs achieve the open circuit condition and are not at reference levels.
5. If clock rising time is longer than 1 ns, ( tR / 2 -0.5) ns should be added to the parameter.
6. Assumed input rise and fall time tT ( tR & tF ) = 1 ns
If tR or tF is longer than 1 ns, transient time compensation should be considered, i.e., [(tr + tf)/2 - 1] ns
should be added to the parameter.
7. Power up Sequence
Power up must be performed in the following sequence.
1) Power must be applied to VDD and VDDQ(simultaneously) when all input signals are held "NOP" state
and both CKE = "H" and DQM = "H." The CLK signals must be started at the same time.
2) After power-up, a pause of 200µ seconds minimum is required. Then, it is recommended that DQM
is held "HIGH" (VDD levels) to ensure DQ output is in high impedance.
3) All banks must be precharged.
4) Mode Register Set command must be asserted to initialize the Mode register.
5) A minimum of 2 Auto-Refresh dummy cycles must be required to stabilize the internal circuitry of the
device.
Preliminary
18
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Timing Waveforms
Figure 1. AC Parameters for Write Timing (Burst Length=4, CAS# Latency=2)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCL
tCH
tCK2
t IS
CKE
t IS
Begin AutoPrecharge
Bank A
Begin AutoPrecharge
Bank B
tIH
t IS
CS#
RAS#
CAS#
WE#
BA0,1
t IH
t IS
ADDR.
CAx
RBx
RBx
CBx
RAy
RAz
CAy
RBy
DQM
tRCD
tDAL
tRC
t IS
DQ
Ax0 Ax1 Ax2
Ax3
Bx0
Bx1
Bx2
Bx3
Activate
W rite with
Activate W rite with
Activate
Command AutoPrecharge CommandAutoPrecharge Command
Bank A
Command
Bank B
Command
Bank A
Bank A
Bank B
Preliminary
19
tW R tRP
tIH
Hi-Z
Ay0
W rite
Command
Bank A
Ay1
Ay2
tRRD
Ay3
Precharge Activate
Command Command
Bank A
Bank A
Rev 0.6
Activate
Command
Bank B
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 2. AC Parameters for Read Timing (Burst Length=2, CAS# Latency=2)
T0
T1
T2
T3
T4
T5
T6
T7
T8
T9
T10
T 11
T12
T13
CLK
tCK2
tCH tCL
CKE
Begin AutoPrecharge
Bank B
t IS
t IH
t IH
t IS
CS#
RAS#
CAS#
WE#
BA0,1
tIH
A10
RBx
RAx
RAy
t IS
A0-A11
RAx
CAx
CBx
RBx
RAy
tRRD
tRAS
tRC
DQM
tAC2
tLZ
tRCD
Hi-Z
DQ
tAC2
Ax0
tRP
tHZ
Ax1
Bx0
t HZ
t OH
Activate
Command
Bank A
Preliminary
Read
Command
Bank A
Activate
Command
Bank B
20
Bx1
Read with
Auto Precharge
Command
Bank B
Precharge
Command
Bank A
Rev 0.6
Activate
Command
Bank A
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 3. Auto Refresh (CBR) (Burst Length=4, CAS# Latency=2)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK2
CKE
CS#
RAS#
CAS#
WE#
BA0,1
A10
RAx
A0-A11
RAx
tRP
DQM
tRC
CAx
tRC
Ax0 Ax1
DQ
PrechargeAll
Command
Preliminary
AutoRefresh
Command
AutoRefresh
Command
Activate
Command
Bank A
21
Ax2 Ax3
Read
Command
Bank A
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 4. Power on Sequene and Auto Refresh (CBR)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK2
CKE
High level
is reauired
Minimum of 2 Refresh Cycles are required
CS#
RAS#
CAS#
WE#
BA0,1
A10
Address Key
A0-A11
DQM
tRP
DQ
tRC
Hi-Z
PrechargeALL
Command
Inputs must be
stable for 200 µs
Preliminary
1st AutoRefresh
Command
Mode Register
Set Command
2nd Auto Refresh
Command
22
Any
Command
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 5. Self Refresh Entry & Exit Cycle
T0
T1
T2
T3
T4
T5
T6
T7
T8
T9
T10
T11
T12
T13
T14
T15
T16
T17
T18
T19
CLK
*Note 2
tRC(min)
*Note 4
*Note 1
*Note 7
tPDE
*Note 3
CKE
tSRX
*Note 5
t IS
*Note 6
CS#
RAS#
*Note 8
*Note 8
CAS#
BA0,1
A0-A11
WE#
DQM
Hi-Z
Hi-Z
DQ
Self Refresh Enter
SelfRefresh Exit
AutoRefresh
Note: To Enter SelfRefresh Mode
1. CS#, RAS# & CAS# with CKE should be low at the same clock cycle.
2. After 1 clock cycle, all the inputs including the system clock can be don't care except for CKE.
3. The device remains in SelfRefresh mode as long as CKE stays "low".
4. Once the device enters SelfRefresh mode, minimum tRAS is required before exit from SelfRefresh.
5.
6.
7.
8.
9.
To Exit SelfRefresh Mode
System clock restart and be stable before returning CKE high.
Enable CKE and CKE should be set high for minimum time of tSRX.
CS# starts from high.
Minimum tRC is required after CKE going high to complete SelfRefresh exit.
4096 cycles of burst AutoRefresh is required before SelfRefresh entry and after SelfRefresh exit if the
system uses burst refresh.
Preliminary
23
Rev 0.6
Sep. 2003
EtronTech
Figure 6.1.
EM669325
4M x 32 LPSDRAM
Clock Suspension During Burst Read (Using CKE)
(Burst Length=4, CAS# Latency=1)
T0
T 1 T2
T3
T4
T5
T6
T
7
T8
T9
T10 T 11 T1
T13 T14 T15 T16 T17 T1
T19 T20 T21 T22
CLK
tCK1
CKE
CS#
RAS#
CAS#
WE#
BA0,1
A10
RAx
A0-A11
RAx
CAx
DQM
tHZ
DQ Hi-Z
Ax3
Ax0
Activate
Command
Bank A
Read
Command
Bank A
Ax1
Clock Suspend
1 Cycle
Ax2
Clock Suspend
2 Cycles
Clock Suspend
3 Cycles
Note: CKE to CLK disable/enable = 1 clock
Preliminary
24
Rev 0.6
Sep. 2003
EtronTech
Figure 6.2.
EM669325
4M x 32 LPSDRAM
Clock Suspension During Burst Read (Using CKE)
(Burst Length=4, CAS# Latency=2)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK2
CKE
CS#
RAS#
CAS#
WE#
BA0,1
A10
RAx
A0-A11
RAx
CAx
DQM
tHZ
DQHi-Z
Ax0
Activate
Command
Bank A
Read
Command
Bank A
Ax1
Clock Suspend
1 Cycle
Ax3
Ax2
Clock Suspend
2 Cycles
Clock Suspend
3 Cycles
Note: CKE to CLK disable/enable = 1 clock
Preliminary
25
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 6.3. Clock Suspension During Burst Read (Using CKE)
(Burst Length=4, CAS# Latency=3)
T0
T 1 T 2 T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK3
CKE
CS#
RAS#
CAS#
WE#
BS0,1
A10
RAx
A0-A9
RAx
CAx
DQM
tHZ
DQ Hi-Z
Ax0
Activate
Command
Bank A
Read
Command
Bank A
Ax1
Ax2
Clock Suspend Clock Suspend
1 Cycle
2 Cycles
Ax3
Clock Suspend
3 Cycles
Note: CKE to CLK disable/enable = 1 clock
Preliminary
26
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 7.1. Clock Suspension During Burst Write (Using CKE)
(Burst Length = 4, CAS# Latency = 1)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK1
CKE
CS#
RAS#
CAS#
WE#
BA0,1
A10
RAx
A0-A11
RAx
CAx
DQM
DQ
Hi-Z
DAx0
DAx1
DAx2
Activate Clock Suspend
Command
1 Cycle
Bank A
Write
Command
Bank A
Clock Suspend
2 Cycles
DAx3
Clock Suspend
3 Cycles
Note: CKE to CLK disable/enable = 1 clock
Preliminary
27
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 7.2. Clock Suspension During Burst Write (Using CKE)
(Burst Length=4, CAS# Latency=2)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK2
CKE
CS#
RAS#
CAS#
WE#
BA0,1
A10
RAx
A0-A11
RAx
CAx
DQM
DQHi-Z
DAx0
Activate
Command
Bank A
DAx1
DAx2
Clock Suspend Clock Suspend
1 Cycle
2 Cycles
DAx3
Clock Suspend
3 Cycles
W rite
Command
Bank A
Note: CKE to CLK disable/enable = 1 clock
Preliminary
28
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 7.3. Clock Suspension During Burst Write (Using CKE)
(Burst Length=4, CAS# Latency=3)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK3
CKE
CS#
RAS#
CAS#
WE#
BA0,1
A10
RAx
A0-A11
RAx
CAx
DQM
DQ
Hi-Z
DAx0
Activate
Command
Bank A
DAx1
DAx2
Clock Suspend Clock Suspend
1 Cycle
2 Cycles
DAx3
Clock Suspend
3 Cycles
Write
Command
Bank A
Note: CKE to CLK disable/enable = 1 clock
Preliminary
29
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 8. Power Down Mode and Clock Mask (Burst Lenght=4, CAS# Latency=2)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK2
tPDE
t IS
CKE
Valid
CS#
RAS#
CAS#
WE#
BS0,1
A10
A0~A11
RAx
RAx
CAx
DQM
tHZ
Hi-Z
DQ
Ax0
ACTIVE
STANDBY
Activate
Read
Command
Command
Bank A
Bank A
Power Down
Power Down
Mode Entry
Mode Exit
Preliminary
Ax1
Ax2
Clock Mask
Start
Clock Mask
End
Ax3
Precharge
Command
Bank A
PRECHARGE
STANDBY
Power Down
Mode Entry
30
Rev 0.6
Power Down
Mode Exit
Any
Command
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 9.1. Random Column Read (Page within same Bank)
(Burst Length=4, CAS# Latency=1)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK1
CKE
CS#
RAS#
CAS#
WE#
BA0,1
A10
A0~A11
RAz
RAw
RAw CAw
CAx
CAy
RAz
CAz
DQM
Hi-Z
DQ
Aw0
Activate
Command
Bank A
Read
Command
Bank A
Preliminary
Aw1 Aw2
Aw3Ax0
Read
Command
Bank A
Ax1
Ay0
Ay1Ay2
Read
Command
Bank A
Ay3
Az0
Az1Az2
Az3
Precharge
Read
Command
Command
Bank A
Bank A
Activate
Command
Bank A
31
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 9.2. Random Column Read (Page within same Bank)
(Burst Length=4, CAS# Latency=2)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK2
CKE
CS#
RAS#
CAS#
WE#
BA0,1
A10
A0~A11
RAz
RAw
RAw
CAw
CAx
RAz
CAy
CAz
DQM
DQHi-Z
Aw0
Activate
Read
Command Command
Bank A
Bank A
Preliminary
Aw1 Aw2
Read
Command
Bank A
Aw3
Ax0
Ax1 Ay0
Read
Command
Bank A
Ay1
Ay2
Az0
Ay3
Precharge Activate
Command Command
Bank A
Bank A
32
Az1
Az2
Az3
Read
Command
Bank A
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 9.3. Random Column Read (Page within same Bank)
(Burst Length=4, CAS# Latency=3)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK3
CKE
CS#
RAS#
CAS#
WE#
BA0,
1
A10
RAz
RAw
A0~A11
RAw
CAy
CAw
RAz
CAx
CAz
DQM
Az0
Hi-Z
DQ
Aw0
Activate
Command
Bank A
Preliminary
Read
Command
Bank A
Aw1 Aw2
Read
Command
Bank A
Aw3
Read
Command
Bank A
33
Ax0 Ax1
Ay0
Ay1
Precharge
Command
Bank A
Ay2
Ay3
Activate
Command
Bank A
Rev 0.6
Read
Command
Bank A
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 10.1. Random Column Write (Page within same Bank)
(Burst Length=4, CAS# Latency=1)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK1
CKE
CS#
RAS#
CAS#
WE#
BA0,1
A10
A0~A11
RBz
RBw
RBw
CBw
CBy
RBz
CBx
CBz
DQM
Hi-Z
DQ
DBw0DBw1DBw2
Activate
Command
Bank A
Write
Command
Bank B
Preliminary
DBw3 DBx0
DBx1 DBy0 DBy1
Write
Command
Bank A
DBy2 DBy3
Write
Command
Bank B
Precharge
Command
Bank B
Activate
Command
Bank B
34
DBz0 DBz1
DBz2 DBz3
Write
Command
Bank B
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 10.2. Random Column Write (Page within same Bank)
(Burst Length=4, CAS# Latency=2)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK2
CKE
CS#
RAS#
CAS#
WE#
BS0,1
A10
A0~A11
RBz
RBw
RBw
CBw
CBx
CBy
RBz
CBz
DQM
Hi-Z
DQ
DBw0
Activate
Write
Command Command
Bank A
Bank B
Preliminary
DBw1
DBw2 DBw3 DBx0
Write
Command
Bank B
DBy0
DBx1
DBy1
DBz0
DBy2 DBy3
Write
Command
Bank B
Precharge Activate
Command Command
Bank B
Bank B
35
DBz2 DBz3
DBz1
Write
Command
Bank B
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 10.3. Random Column Write (Page within same Bank)
(Burst Length=4, CAS# Latency=3)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK3
CKE
CS#
RAS#
CAS#
WE#
BA0,1
RBz
RBw
A10
A0~A11
RBw
CBw
CBx
CBy
RBz
CBz
DQM
DQ
Hi-Z
DBw0 DBw1DBw2 DBw3 DBx0 DBx1
Activate
Command
Bank A
Preliminary
Write
Command
Bank B
Write
Command
Bank B
DBy0
DBz0
DBy1 DBy2 DBy3
Write
Command
Bank B
36
Precharge
Command
Bank B
Activate
Command
Bank B
Rev 0.6
DBz1
DBz2
Write
Command
Bank B
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 11.1. Random Row Read (Interleaving Banks)
(Burst Length=8, CAS# Latency=1)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK1
CKE High
CS#
RAS#
CAS#
WE#
BA0,1
RAx
RBx
A10
RBy
RAx
RBx CBx
A0~A11
RBy
CBy
CAx
tRCD
DQ
tRP
tAC1
DQM
Hi-Z
Bx0
Activate
Command
Bank B
Read
Command
Bank B
Preliminary
Bx1
Bx2
Bx3
Bx4
Bx5
Bx6
Bx7
Ax0
Ax1
Ax2
Ax3
Ax4
Ax5
Ax6 Ax7
Precharge
Command
Bank B
Activate
Read
Command
Command
Bank B
Bank A
Read
Command
Bank B
Activate
Command
Bank A
37
By0
Rev 0.6
By1
By2
Precharge
Command
Bank A
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 11.2. Random Row Read (Interleaving Banks)
(Burst Length=8, CAS# Latency=2)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK2
High
CKE
CS#
RAS#
CAS#
WE#
BA0,1
RBx
A10
RAx
RBx
A0~A11
RAx
CBx
tRCD
RBy
RBy
CAx
tAC2
tRP
DQM
Hi-Z
DQ
Activate
Command
Bank B
Preliminary
Bx0
Read
Command
Bank B
CBy
Bx1
Bx2
Bx3 Bx4
Activate
Command
Bank A
Bx5 Bx6
Bx7
Ax0
Precharge
Command
Read Bank B
Command
Bank A
38
Ax1
Ax2Ax3
Ax4
Ax5
Activate
Command
Bank B
Ax6
Ax7
By0
By1
Read
Command
Bank B
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 11.3. Random Row Read (Interleaving Banks)
(Burst Length=8, CAS# Latency=3)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK3
High
CKE
CS#
RAS#
CAS#
WE#
BA0,1
A10
RBx
RAx
RBx
A0~A9
RBy
RAx
tRCD
RBy
CAx
CBx
tAC3
tRP
DQM
Hi-Z
DQ
Bx0
Activate
Command
Bank B
Preliminary
Read
Command
Bank B
CBy
Bx1 Bx2
Bx3
Bx4
Activate
Command
Bank A
Bx5
Read
Command
Bank A
39
Bx6
Ax7
Bx7
Precharge
Command
Bank B
Ax0 Ax1 Ax2
Ax3
Activate
Command
Bank B
Rev 0.6
Ax4
By0
Ax5Ax6
Read
Command
Bank B
Precharge
Command
Bank A
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 12.1. Random Row Write (Interleaving Banks)
(Burst Length=8, CAS# Latency=1)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK1
CKE
High
CS#
RAS#
CAS#
WE#
BA0,1
A10
RAx
A0~A11
RAx
CAx
RBx
RAy
RBxCBx
RAy
tRCD
CAy
tRP
t WR
DQM
DQ
Hi-Z
DAx0
DAx1 DAx2
DAx3
Activate
Command
Bank A
Write
Command
Bank A
Preliminary
DAx4
DAx5DAx6 DAx7 DBx0 DBx1 DBx2 DBx3DBx4 DBx5 DBx6 DBx7
Activate
Command
Bank B
Write
Command
Bank B
Precharge
Command
Bank A
Activate
Command
Bank A
40
DAy0 DAy1 DAy2 DAy3
Precharge
Command
Bank B
Rev 0.6
Write
Command
Bank A
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 12.2. Random Row Write (Interleaving Banks)
(Burst Length=8, CAS# Latency=2)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK2
CKE High
CS#
RAS#
CAS#
WE#
BA0,1
A10
A0~A11
RAx
RAy
RBx
RAx
CAx
RBx
RAy
CBx
tRCD
tWR*
CAy
tRP
tWR*
DQM
DQ Hi-Z
DAx0 DAx1 DAx2 DAx3 DAx4DAx5
Activate
Write
Command Command
Bank A Bank A
DAx6
DAx7 DBx0 DBx1 DBx2 DBx3 DBx4DBx5 DBx6 DBx7
Activate
Command
Bank B
Write
Command
Bank B
Precharge
Command
Bank A
Activate
Command
Bank A
DAy0 DAy1DAy2
DAy3 DAy4
Write
Command
Bank A
Precharge
Command
Bank B
* tWR > tWR(min.)
Preliminary
41
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 12.3. Random Row Write (Interleaving Banks)
(Burst Length=8, CAS# Latency=3)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK3
High
CKE
CS#
RAS#
CAS#
WE#
BA0,1
A10
RAx
A0~A11
RAx
RBx
CAx
RAy
RAy
CBx
RBx
tRCD
tWR*
CAy
tRP
tWR*
DQM
Hi-Z
DQ
Activate
Command
Bank A
DAx0DAx1
Write
Command
Bank A
DAx2 DAx3DAx4 DAx5
DAx6 DAx7
Activate
Command
Bank B
DBx0 DBx1DBx2
Write
Command
Bank B
DBx3 DBx4 DBx5 DBx6 DBx7 DAy0
Precharge
Command
Bank A
Activate
Command
Bank A
Write
Command
Bank A
DAy1 DAy2 DAy3
Precharge
Command
Bank B
* tWR > tWR(min.)
Preliminary
42
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 13.1. Read and Write Cycle (Burst Length=4, CAS# Latency=1)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK1
CKE
CS#
RAS#
CAS#
WE#
BA0,1
A10
A0~A11
RAx
RAx CAx
CAy
CAz
DQM
DQ Hi-Z
Az3
Ax0 Ax1
Activate
Command
Bank A
Read
Command
Bank A
Preliminary
Ax2
Ax3
DAy0DAy1
DAy3
Az0
Read
The Write Data
Write
Command is Masked with a Command
Bank A
Zero Clock
Bank A
Latency
43
Az1
The Read Data
is Masked with a
Two Clock
Latency
Rev 0.6
Precharge
Command
Bank B
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 13.2. Read and Write Cycle (Burst Length=4, CAS# Latency=2)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK2
CKE
CS#
RAS#
CAS#
WE#
BA0,1
A10
RAx
A0~A11
RAx
CAx
CAz
CAy
DQM
DQ Hi-Z
Ax0
Activate
Command
Bank A
Preliminary
Read
Command
Bank A
Ax1
Ax2 Ax3
DAy0 DAy1
DAy3
Write
The Write Data
Command is Masked with a
Bank A
Zero Clock
Latency
44
Az0
Read
Command
Bank A
Rev 0.6
Az1
Az3
The Read Data
is Masked with a
Two Clock
Latency
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 14.1. Interleaving Column Read Cycle (Burst Length=4, CAS# Latency=2)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK2
CKE
CS#
RAS#
CAS#
WE#
BA0,1
A10
RAx
A0~A11
RAx
CAy
tRCD
DQM
DQ
RAx
Hi-Z
Read
Command
Bank A
CBw
CBx
CBy
CAy
CBz
By0
By1 Ay0
tAC2
Ax0
Activate
Command
Bank A
Preliminary
RAx
Ax1 Ax2
Activate
Command
Bank B
Ax3 Bw0
Read
Read
Command Command
Bank B
Bank B
Bw1
Bx0 Bx1
Read
Command
Bank B
45
Read
Command
Bank A
Ay1
Bz0
Read
Command
Bank B
Precharge
Command
Bank A
Rev 0.6
Bz1 Bz2 Bz3
Precharge
Command
Bank B
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 14.2. Interleaved Column Read Cycle (Burst Length=4, CAS# Latency=3)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK3
CKE
CS#
RAS#
CAS#
WE#
BA0,1
A10
RAx
A0~A11
RAx
RBx
CAx
tRCD
DQM
RBx
CBx
Ax0
Preliminary
CAy
tAC3
Hi-Z
DQ
Activate
Command
Bank A
CBz
CBy
Read
Command
Bank A
Activate
Command
Bank B
Ax1 Ax2
Read
Command
Bank B
Ax3
Bx0
Read
Command
Bank B
46
Bx1
By0 By1
Read
Command
Bank B
Bz0
Bz1 Ay0
Read Prechaerge
Command
Command
Bank A Bank B
Ay1
Ay2
Ay3
Precharge
Command
Bank A
Rev 0.6
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 15.1. Interleaved Column Write Cycle (Burst Length=4, CAS# Latency=1)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK1
CKE
CS#
RAS#
CAS#
WE#
BA0,1
A10
RAx
RBw
A0~A11
RAx
CAx RBw
CBw
CBy
CBx
CBz
CAy
tRP
DQM
tWR tRP
tRCD
tRRD
DQ Hi-Z
DAx0
Activate
Command
Bank A
DAx1 DAx2 DAx3 DBw0DBw1 DBx0
Activate
Command
Bank B
Write
Command
Bank B
DBx1 DBy0
Write
Command
Bank B
DBy1 DAy0
Write
Command
Bank B
Write
Command
Bank A
Preliminary
47
DAy1
Write
Command
Bank A
DBz0 DBz1
DBz2
DBz3
Write
Command
Bank B
Precharge
Command
Bank A
Rev 0.6
Precharge
Command
Bank B
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 15.2. Interleaved Column Write Cycle (Burst Length=4, CAS# Latency=2)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK2
CKE
CS#
RAS#
CAS#
WE#
BA0,1
A10
RAx
A0~A11
RAx
DQM
RBw
RBw
CAx
CBw
CBx
CBy
CAy
tRCD
CBz
tRP
tWR
tRP
tRRD
Hi-Z
DQ
DAx0
DAx1
Activate
Command
Bank A
Preliminary
Write
Command
Bank A
DAx2
Activate
Command
Bank B
DAx3DBw0 DBw1 DBx0
Write
Command
Bank B
Write
Command
Bank B
DBx1DBy0
DBy1DAy0 DAy1 DBz0 DBz1 DBz2
Write
Command
Bank B
48
Write
Command
Bank A
Write
Command
Bank B
Precharge
Command
Bank A
Rev 0.6
DBz3
Precharge
Command
Bank B
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 15.3. Interleaved Column Write Cycle (Burst Length=4, CAS# Latency=3)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK3
CKE
CS#
RAS#
CAS#
WE#
BA0,1
A10
RAx
RBw
A0~A11
RAx
CAx RBw
CBw
CBx
CBy
CAy
tRCD
DQM
CBz
tWR
tRP
tWR(min)
tRRD > tRRD(min)
DQ
Hi-Z
DAx0 DAx1 DAx2 DAx3DBw0
Activate
Command
Bank A
Preliminary
Activate
Command
Bank B
Write
Command
Bank A
DBw1DBx0 DBx1 DBy0 DBy1 DAy0 DAy1 DBz0 DBz1 DBz2 DBz3
Write
Command
Bank B
Write
Command
Bank B
49
Write
Command
Bank B
Write
Command
Bank A
Write
Command
Bank B
Precharge
Command
Bank A
Rev 0.6
Precharge
Command
Bank B
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
Figure 16. Random Row Read (Interleaving Banks)
(Burst Length=2, CAS# Latency=1)
T0
T 1 T2
T3
T4
T5
T6
T7
T8
T9
T10 T 11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22
CLK
tCK1
CKE High
Begin Auto
Precharge
Bank B
Begin Auto
Precharge
Bank A
Begin Auto
Precharge
Bank B
Begin Auto
Precharge
Bank A
Begin Auto
Precharge
Bank B
Begin Auto
Precharge
Bank A
Begin Auto
Precharge
Bank B
Begin Auto
Precharge
Bank A
Begin Auto
Precharge
Bank B
Begin Auto
Precharge
Bank A
CS#
RAS#
CAS#
WE#
BA0,1
A10
A0~A11
RAu
RBu
CBu
RBu
RAu CAu
RBv
RAv
RBv CBv
RAv
tRP
DQM
DQ
Bu0
Activate
Command
Bank B
Read
Bank B
with Auto
Precharge
Preliminary
Au1
Activate
Command
Bank B
Read
Bank A
with Auto
Precharge
CAv
tRP
Bu1Au0
Activate
Command
Bank A
RBw
Activate
Command
Bank A
Read
Bank B
with Auto
Precharge
RBw
tRP
Bv0 Bv1
CBw
Activate
Command
Bank A
Read
Bank B
with Auto
Precharge
CBx RAx CAx
tRP
Av1 Bw0 Bw1
Activate
Command
Bank B
RAx
RAw CAw RBx
tRP
Av0
Read
Bank A
with Auto
Precharge
RBx
RAw
tRP
Aw0
Activate
Command
Bank B
Read
Bank A
with Auto
Precharge
50
Aw1Bx0
Read
Bank B
with Auto
Precharge
RAy
RBy CBy
RAy CAy RBz
tRP
Bx1
Activate
Command
Bank A
RBz
RBy
tRP
Read
Bank A
with Auto
Precharge
Rev 0.6
tRP
By1 Ay0 Ay1
Activate
Command
Bank A
Read
Bank B
with Auto
Precharge
CBz RAz
tRP
Ax0 Ax1 By0
Activate
Command
Bank B
RAz
Activate
Command
Bank B
Read
Bank A
with Auto
Precharge
Bz0
Activate
Command
Bank A
Read
Bank B
with Auto
Precharge
Sep. 2003
EtronTech
EM669325
4M x 32 LPSDRAM
.90-FBGA, 11mm x 13mm plastic package
.9x15 ball array with 3 depopulated rows in center
.0.8mm ball pitch
.Low-profile, 1.2mm max height
Features of the Low-Power SDRAM Package:
(Ball-Side View)
6.40
0.80
11.20
0.80
13.00
5.60
6.50
3.20
5.50
11.00
Φ = 0.45±0.05
1.40 max
0.35
All dimemsions are in mm.
Preliminary
51
Rev 0.6
Sep. 2003
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