ETRON EM68932DVKB

EtronTech
EM68932DVKB
4M x 32 Mobile DDR Synchronous DRAM (SDRAM)
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Features
•
•
•
•
•
•
Fast clock rate: 166/133 MHz
Differential Clock CK & CK
Bi-directional DQS
Four internal banks, 1M x 32-bit for each bank
Edge-aligned with read data, centered in write data
Programmable Mode and Extended Mode Registers
- CAS Latency: 2, or 3
- Burst length: 2, 4, or 8
- Burst Type: Sequential & Interleaved
- PASR (Partial Array Self Refresh)
- Auto TCSR (Temperature Compensated Self
Refresh)
- DS (Drive Strength)
• Individual byte writes mask control
• DM Write Latency = 0
• Precharge Standby Current = 100 µA
• Self Refresh Current = 200 µA
• Deep power-down Current = 10 µA max. at 85℃
• Auto Refresh and Self Refresh
• 4096 refresh cycles / 64ms
• No DLL (Delay Lock Loop), to reduce power; CK to
DQS is not synchronized.
• Power supplies: VDD & VDDQ = +1.8V+0.15V/-0.1V
• Interface: LVCMOS
• Ambient Temperature TA = -25 ~ 85℃,
• 90-ball 8mm x 13mm VFBGA package
- Pb and Halogen Free
Overview
The EM68932D is 134,217,728 bits of double data
rate synchronous DRAM organized as 4 banks of
1,048,576 words by 32 bits. The synchronous
operation with Data Strobe allows extremely high
performance. EM68932D is applied to reduce
leakage and refresh currents while achieving very
high speed. I/O transactions are possible on both
edges of the clock. The ranges of operating
frequencies, programmable burst length and
programmable latencies allow the device to be
useful for a variety of high performance memory
system applications.
Advanced (Rev. 1.0 Aug. /2009)
Table 1. Ordering Information
Part Number
Clock Frequency
EM68932DVKB-6H
EM68932DVKB-75H
166MHz
133MHz
IDD6 Package
200 µA VFBGA
200 µA VFBGA
VK: indicates VFBGA package
B: indicates Generation Code
H: indicates Pb and Halogen Free for VFBGA Package
Figure 1. Ball Assignment (Top View)
1
2
3
A
VSS
DQ31
B
VDDQ.
C
…
7
8
9
VSSQ
VDDQ
DQ16
VDD
DQ29
DQ30
DQ17.
DQ18
VSSQ
VSSQ
DQ27
DQ28
DQ19
DQ20
VDDQ
D
VDDQ
DQ25
DQ26
DQ21
DQ22
VSSQ
E
VSSQ
DQS3
DQ24
DQ23
DQS2
VDDQ
F
VDD
DM3
NC
NC
DM2
VSS
G
CKE
CK
CK
WE
CAS
RAS
H
A9
A11
NC
CS
BA0
BA1
J
A6
A7
A8
A10/AP
A0
A1
K
A4
DM1
A5
A2
DM0
A3
L
VSSQ
DQS1
DQ8
DQ7
DQS0
VDDQ
M
VDDQ
DQ9
DQ10
DQ5
DQ6
VSSQ
N
VSSQ
DQ11
DQ12
DQ3
DQ4
VDDQ
P
VDDQ
DQ13
DQ14
DQ1
DQ2
VSSQ
R
VSS
DQ15
VSSQ
VDDQ
DQ0
VDD
Etron Technology, Inc.
No. 6, Technology Rd. V, Hsinchu Science Park, Hsinchu, Taiwan 30078, R.O.C.
TEL: (886)-3-5782345
FAX: (886)-3-5778671
Etron Technology, Inc. reserves the right to change products or specification without notice.
EtronTech
EM68932DVKB
Figure 2. lock Diagram
PASR, DS
CK
CK
CLOCK
BUFFER
EXTENDED
MODE
REGISTER
SELF REFRESH
LOGIC & TIMER
CS
RAS
CAS
WE
1M x 32
CELL ARRAY
(BANK #0)
Column Decoder
COMMAND
DECODER
COLUMN
COUNTER
MODE
REGISTER
Row
Decoder
CONTROL
SIGNAL
GENERATOR
A10/AP
1M x 32
CELL ARRAY
(BANK #1)
Column Decoder
~
A9
A11
BA0
BA1
Row
Decoder
ADDRESS
BUFFER
A0
REFRESH
COUNTER
DQS0
DATA
STROBE
BUFFER
~
DQS3
Row
Decoder
CKE
DQ0
1M x 32
CELL ARRAY
(BANK #2)
Column Decoder
DQ
Buffer
1M x 32
CELL ARRAY
(BANK #3)
Column Decoder
~
DM0
Row
Decoder
~
DQ31
DM3
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EtronTech
EM68932DVKB
Pin Descriptions
Table 2. Pin Details of EM68932D
Symbol
Type
Description
CK, CK
Input
Differential Clock: CK and CK are differential clock inputs. All address and
control input signals are sampled on the crossing of the positive edge of CK and
negative edge of CK . Input and output data is referenced to the crossing of CK and
CK (both directions of the crossing)
CKE
Input
Clock Enable: CKE activates (HIGH) and deactivates (LOW) the CK signal.
Internal clock signals and device input buffers and output drivers. Taking CKE Low
provides Precharge Power Down and Self Refresh operation (all banks idle) or
Active Power Down (Row Active in any bank). CKE is synchronous for all functions
except for disabling outputs, which is asynchronous. Input buffers, excluding
CK, CK and CKE, are disabled during Power Down and Self Refresh modes to
reduce standby power consumption.
BA0, BA1
Input
Bank Activate: BA0 and BA1 define to which bank the BankActivate, Read, Write,
or BankPrecharge command is being applied. BA0 and BA1 also determine which
mode register (MRS or EMRS) is loaded during a Mode Register Set command.
A0-A11
Input
Address Inputs: A0-A11 are sampled during the BankActivate command (row
address A0-A11) and Read/Write command (column address A0-A7 with A10
defining Auto Precharge).
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
CK. When RAS and CS are asserted "LOW" and CAS is asserted "HIGH," either
the BankActivate command or the Precharge command is selected by the WE
signal. When the WE is asserted "HIGH," the BankActivate command is selected
and the bank designated by BA is turned on to the active state. When the WE is
asserted "LOW," the Precharge command is selected and the bank designated by
BA is switched to the idle state after the precharge operation.
CAS
Input
Column Address Strobe: The CAS signal defines the operation commands in
conjunction with the RAS and WE signals and is latched at the positive edges of
CK. When RAS is held "HIGH" and CS is asserted "LOW," the column access is
started by asserting CAS "LOW." Then, the Read or Write command is selected
by asserting WE "HIGH " or LOW"."
WE
Input
Write Enable: The WE signal defines the operation commands in conjunction
with the RAS and CAS signals and is latched at the positive edges of CK. The
WE input is used to select the BankActivate or Precharge command and Read or
Write command.
DQS0 -DQS3
Input /
Bidirectional Data Strobe: The DQSx signals are mapped to the following data
bytes: DQS0 to DQ0-DQ7, DQS1 to DQ8-DQ15, DQS2 to DQ16-DQ23, and DQS3
to DQ24-DQ31.
Output
DM0 - DM3
Input
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Data Input Mask: DM0-DM3 are byte specific. Input data is masked when DM is
sampled HIGH during a write cycle. DM3 masks DQ31-DQ24, DM2 masks DQ23DQ16, DM1 masks DQ15-DQ8, and DM0 masks DQ7-DQ0.
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EM68932DVKB
DQ0 – DQ31
Input /
Output
Data I/O: The DQ0-DQ31 input and output data are synchronized with the positive
edges of CK and CK . The I/Os are byte-maskable during Writes.
VDD
Supply
Power Supply: +1.8V+0.15V/-0.1V
VSS
Supply
Ground
VDDQ
Supply
DQ Power: +1.8V+0.15V/-0.1V. Provide isolated power to DQs for improved noise
immunity.
VSSQ
Supply
DQ Ground: Provide isolated ground to DQs for improved noise immunity.
NC
-
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No Connect: No internal connection, these pins suggest to be left unconnected.
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EM68932DVKB
Operation Mode
Table 3 shows the truth table for the operation commands.
Table 3. Truth Table (Note (1), (2))
Command
State
BankActivate
BankPrecharge
PrechargeAll
Write
Write and AutoPrecharge
Read
Read and Autoprecharge
Mode Register Set
Extended Mode Register Set
No-Operation
Device Deselect
Burst Stop
AutoRefresh
SelfRefresh Entry
Idle(3)
SelfRefresh Exit
Any
Any
Active(3)
Active(3)
Active(3)
Active(3)
Idle
Idle
Any
Any
Active(4)
Idle
Idle
Idle
(Self Refresh)
CKEn-1 CKEn DM BA1 BA0
A10
A11, A9-0
CS
RAS
CAS
L
L
L
L
L
L
L
L
L
L
H
L
L
L
H
L
H
L
H
L
L
L
L
H
H
H
H
L
L
H
X
H
L
L
X
H
X
H
X
H
H
H
H
L
L
L
L
L
L
H
X
H
L
L
X
H
X
H
X
H
WE
H
L
L
L
L
H
H
L
L
H
X
L
H
H
X
H
X
H
X
H
L
H
H
L
X
X
X
X
H
H
H
H
H
H
H
H
H
H
H
H
H
H
X
X
X
X
X
X
X
X
X
X
X
X
H
L
X
X
X
V
V
X
X
X
X
X
X
X
X
X
V
V
X
V
V
V
V
L
H
X
X
X
X
X
V
V
X
V
V
V
V
L
L
X
X
X
X
X
Row Address
L
X
H
X
L
Column
H
Address
L
A0~A7
H
X
X
X
X
X
X
X
X
X
X
L
H
X
X
X
X
X
OP code
Power Down Mode Entry
Idle/Active(5
)
H
L
X
X
X
X
X
Power Down Mode Exit
Any
(Power Down)
L
H
X
X
X
X
X
Deep Power Down Entry
Any
H
L
X
X
X
X
X
Deep Power Down Exit
Any
L
H X X
X
X
X
H
X
Data Mask Enable
Active
H
X
L X
X
X
X
X
X
Data Mask Disable
Active
H
X H X
X
X
X
X
X
Note: 1. V = Valid data, X = Don't Care, L = Low level, H = High level
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 BA0, BA1signals.
4. Read burst stop with BST command for all burst types.
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.
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EM68932DVKB
Functional Description
This 128Mb Mobile DDR SDRAM is a high-speed CMOS, dynamic random-access memory containing
134,217,728 bits. It is internally configured as a quad-bank DRAM. Each of the 33,554,432-bit banks is
organized as 4,096 rows by 256 columns by 32 bits. The 128Mb Mobile DDR SDRAM uses a double data rate
architecture to achieve high speed operation. EM68932D is applied to reduce leakage and refresh currents
while achieving very high speed. 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 balls. Single read or write
access for the 128Mb Mobile DDR SDRAM consists of a single 2n-bit wide, one-clock-cycle data transfer at
the internal DRAM core and two corresponding n-bit wide, one-half-clock-cycle data transfers at the I/O balls.
Read and write accesses to the Mobile 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 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, A0A11 select the row). The address bits (BA0, BA1 select the bank, A0-A7 select the column) registered
coincident with the READ or WRITE command are used to select the starting column location for the burst
access.
Note that the DLL (Delay Lock Loop) circuitry used on standard DDR devices is not included in the Mobile
DDR SDRAM. It has been omitted to save power.
Prior to normal operation, the Mobile DDR SDRAM must be initialized.
z Power-Up and Initialization
Mobile DDR SDRAMs must be powered up and initialized in a predefined manner. Operational procedures
other than those specified may result in undefined operation. To properly initialize the Mobile DDR SDRAM,
this sequence must be followed:
1. To prevent device latch-up, it is recommended that core power (VDD) and I/O power (VDDQ) be from the
same power source and be brought up simultaneously. If separate power sources are used, VDD must
lead VDDQ.
2. Once power supply voltages are stable and CKE has been driven High, it is safe to apply the clock.
3. Once the clock is stable, a 200µs (minimum) delay is required by the Mobile DDR SDRAM prior to
applying an executable command. During this time, NOP or Deselect commands must be issued on the
command bus.
4. Issue a Precharge All command.
5. Issue NOP or Deselect commands for at least tRP time.
6. Issue an Auto Refresh command followed by NOP or Deselect commands for at least tRFC time. Issue a
second Auto Refresh command followed by NOP or Deselect commands for at least tRFC time. As part of
the individualization sequence, two Auto Refresh commands must be issued. Typically, both of these
commands are issued at this stage as described above. Alternately, the second Auto Refresh command
and NOP or Deselect sequence can be issued between steps 10 and 11.
7. Using the Mode Register Set command, load the standard Mode Register as desired.
8. Issue NOP or Deselect commands for at least tMRD time.
9. Using the Mode Register Set command, load the Extended Mode Register to the desired operating
modes. Note that the sequence in which the standard and extended mode registers are programmed is
not critical.
10. Issue NOP or Deselect commands for at least tMRD time.
11. The Mobile DDR SDRAM has been properly initialized and is ready to receive any valid command.
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EM68932DVKB
z Mode Register Set(MRS)
The Mode Register stores the data for controlling various operating modes of a DDR SDRAM. It programs
CAS Latency, Burst Type, and Burst Length to make the Mobile DDR SDRAM useful for a variety of
applications. The default value of the Mode Register is not defined; therefore the Mode Register must be
written by the user. Values stored in the register will be retained until the register is reprogrammed, the
device enters Deep Power Down mode, or power is removed from the device. The Mode Register is written
by asserting Low on CS , RAS , CAS , WE , BA1 and BA0 (the device should have all banks idle with no
bursts in progress prior to writing into the mode register, and CKE should be High). The state of address
pins A0~A11 and BA0, BA1 in the same cycle in which CS , RAS , CAS and WE are asserted Low is
written into the Mode Register. A minimum of two clock cycles, tMRD, are required to complete the write
operation in the Mode Register. The Mode Register is divided into various fields depending on functionality.
The Burst Length uses A0~A2, Burst Type uses A3, and CAS Latency (read latency from column address)
uses A4~A6. A logic 0 should be programmed to all the undefined addresses to ensure future compatibility.
Reserved states should not be used to avoid unknown device operation or incompatibility with future
versions. Refer to the table for specific codes for various burst lengths, burst types and CAS latencies.
Table 4. Mode Register Bitmap
BA1 BA0 A11 A10
0
0
A9
0
A8
A7
A6
0
0
CAS Latency
A6 A5 A4 CAS Latency
0
0
0
Reserved
0
0
1
Reserved
0
1
0
2
0
1
1
3
1
0
0
Reserved
1
0
1
Reserved
1
1
0
Reserved
1
1
1
Reserved
A5
A4
A3
BT
A2
A1
A0 Address Field
Burst Length
A3 Burst Type
0 Sequential
1 Interleave
A2
0
0
0
0
1
1
1
1
A1
0
0
1
1
0
0
1
1
A0
0
1
0
1
0
1
0
1
Mode Register
Burst Length
Reserved
2
4
8
Reserved
Reserved
Reserved
Reserved
CK
CK
Command
NOP
PRE
ALL
NOP
MRS*1
NOP
tRP*2
NOP
Any
Command
NOP
NOP
tMRD= 2*tCK
*1: MRS can be issued only with all banks in the idle state.
*2: A minimum delay of tRP is required before issuing an MRS command.
Don’t Care
Figure 3. de Register Set Cycle
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EM68932DVKB
Burst Mode Operation
Burst Mode operation is used to provide a constant flow of data to memory locations (write cycle) or from
memory locations (read cycle). There are two parameters that define how the Burst Mode operates.
These parameters include Burst Type and Burst Length and are programmed by addresses A0~A3 during
the Mode Register Set command. Burst Type is used to define the sequence in which the burst data will
be delivered from or stored to the DDR SDRAM. Two types of burst sequences are supported, Sequential
and Interleaved. See the table below. The Burst Length controls the number of bits that will be output after
a read command, or the number of bits to be input after a write command. The Burst Length can be
programmed to have a value of 2, 4, or 8.
Table 5.Burst Definition
Burst
Length
2
4
8
Start Address
A3 A2 A1 A0
X
X
X
0
X
X
X
1
X
X
0
0
X
X
0
1
X
X
1
0
X
X
1
1
X
0
0
0
X
0
0
1
X
0
1
0
X
0
1
1
X
1
0
0
X
1
0
1
X
1
1
0
X
1
1
1
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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
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EM68932DVKB
z Extended Mode Register Set (EMRS )
The Extended Mode Register is designed to support Partial Array Self Refresh and Driver Strength. The
EMRS cycle is not mandatory, and the EMRS command needs to be issued only when either PASR or DS
is used. The Extended Mode Register is written by asserting Low on CS , RAS , CAS , WE , and BA0 and
High on BA1 (the device should have all banks idle with no bursts in progress prior to writing into the
Extended Mode Register, and CKE should be High). Values stored in the register will be retained until the
register is reprogrammed, the device enters Deep Power Down mode, or power is removed from the
device. The state of address pins A0~A11 and BA0, BA1 in the same cycle in which CS , RAS , CAS
and WE are asserted Low is written into the Extended Mode Register. Two clock cycles, tMRD, are required
to complete the write operation in the Extended Mode Register. A0~A2 are used for Partial Array Self
Refresh and A5~A6 are used for Driver Strength. An automatic Temperature Compensated Self Refresh
function is included with a temperature sensor embedded into this device. A3~A4 are no longer used to
control this function; any inputs applied to A3~A4 during EMRS are ignored. All the other address pins,
A7~A11 and BA0, must be set to Low for proper EMRS operation. Refer to the tables below for specific
codes. If the user does not write values to the Extended Mode Register, DS defaults to Full Strength; and
PASR defaults to the Full Array.
Table 6. Extend Mode Register Bitmap
BA1 BA0 A11 A10 A9
1
0
0
A6
0
0
1
1
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A5
0
1
0
1
A8
A7
0
0
A6
A5
DS
Drive Strength
Full Strength
1/2 Strength
1/4 Strength
1/8 Strength
A4
A3
0
0
A2
A1
PASR
A0
Address Field
Extended Mode Register
A2 A1 A0 Partial Array Self Refresh Coverage
0 0 0
Full Array (All Banks)
0 0 1
Half of Full Array (BA1=0)
0 1 0 Quarter of Full Array (BA1=BA0=0)
0 1 1
Reserved
1 0 0
Reserved
1 0 1
Reserved
1 1 0
Reserved
1 1 1
Reserved
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EM68932DVKB
TEMPERATURE COMPENSATED SELF REFRESH
In order to reduce power consumption, a Mobile DDR SDRAM includes the internal temperature sensor
and other circuitry to control Self Refresh operation automatically according to two temperature ranges:
max. 40°C and max. 85°C
Table 7. IDD6 Specifications and Conditions
Temperature Range
Self Refresh Current (IDD6)
Full Array
1/2 of Full Array
1/4 of Full Array
Unit
Max. 40°C
200
150
120
µA
Max. 85°C
160
110
90
µA
PARTIAL ARRAY SELF REFRESH
For further power savings during Self Refresh, the PASR feature allows the controller to select the amount
of memory that will be refreshed during Self Refresh. The refresh options are all banks (banks 0, 1, 2 and
3); two banks (bank 0 and 1); and one bank (bank 0). Write and Read commands can still affect any bank
during standard operations, but only the selected banks will be refreshed during Self Refresh. Data in
unselected banks will be lost.
z Bank Activation / Row Address Command
The Bank Activation / Row Address command, also called the Active command, is issued by holding CAS
and WE High with CS and RAS Low at the rising edge of the clock (CK). The DDR SDRAM has four
independent banks, so two Bank Select Addresses (BA0, BA1) are required. The Active command must be
applied before any read or write operation is executed. The delay from the Active command to the first
Read or Write command must meet or exceed the minimum of RAS to CAS delay time (tRCD min). Once a
bank has been activated, it must be precharged before another Active command can be applied to the
same bank. The minimum time interval between interspersed Active commands (Bank 0 to Bank 3, for
example) is the bank to bank delay time (tRRD min).
z Burst Read Operation
Burst Read operation in a DDR SDRAM is initiated by asserting CS and RAS Low while holding RAS and
WE High at the rising edge of the clock (CK) after tRCD from the Active command. The address inputs
(A0~A7) determine the starting address for the Burst. The Mode Register sets the type of burst (Sequential
or Interleaved) and the burst length (2, 4, or 8). The first output data is available after the CAS Latency
from the Read command, and the consecutive data bits are presented on the falling and rising edges of
Data Strobe (DQS) as supplied by the DDR SDRAM until the burst is completed.
z Burst Write Operation
The Burst Write command is issued by having CS , CAS and WE Low while holding RAS High at the
rising edge of the clock (CK). The address inputs determine the starting column address. There is no write
latency relative to DQS required for the Burst Write cycle. The first data for a Burst Write cycle must be
applied at the first rising edge of the data strobe enabled after tDQSS from the rising edge of the clock when
the Write command was issued. The remaining data inputs must be supplied on each subsequent falling
and rising edge of Data Strobe until the burst length is completed. After the burst has finished, any
additional data supplied to the DQ pins will be ignored.
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EM68932DVKB
z Burst Interruption
Read Interrupted by Read
Burst Read can be interrupted before completion of the burst by a new Read command to any bank. When
the previous burst is interrupted, data bits from the remaining addresses are overridden by data from the
new addresses with the full burst length. The data from the previous Read command continues to appear
on the outputs until the CAS latency from the interrupting Read command is satisfied. At this point the data
from the interrupting Read command appears. The Read to Read interval is a minimum of 1 clock.
Read Interrupted by Burst Stop & Write
To interrupt Burst Read with a write command, the Burst Stop command must be asserted to avoid data
contention on the I/O bus by placing the DQ (output drivers) in a high impedance state. To ensure the DQ
are tri-stated one cycle before the beginning of the write operation, the Burst Stop command must be
applied at least 2 clock cycles for CL = 2 and at least 3 clock cycles for CL = 3 before the Write command.
Read Interrupted by Precharge
Burst Read can be interrupted by a Precharge of the same bank. A minimum of 1 clock cycle is required for
the read precharge interval. A Precharge command to output disable latency is equivalent to the CAS
latency.
Write Interrupted by Write
A Burst Write can be interrupted by the new Write command before completion of the previous Burst Write,
with the only restriction being that the interval that separates the commands must be at least one clock
cycle. When the previous burst is interrupted, the remaining addresses are overridden by the new
addresses and the new data will be written into the device until the programmed Burst Length is satisfied.
Write Interrupted by Read & DM
A Burst Write can be interrupted by a Read command to any bank. The DQ must be in the high impedance
state at least one clock cycle before the interrupting read data appears on the outputs to avoid data
contention. When the Read command is to be asserted, any residual data from the Burst Write sequence
must be masked by DM. The delay from the last data to the Read command (tWTR) is required to avoid data
contention inside the DRAM. Data presented on the DQ pins before the Read command is initiated will
actually be written to the memory. A Read command interrupting a write sequence can not be issued at the
next clock edge following the Write command.
Write Interrupted by Precharge & DM
A Burst Write can be interrupted by a Precharge of the same bank before completion of the previous burst.
A write recovery time (tWR) is required from the last data to the Precharge command. When the Precharge
command is asserted, any residual data from the Burst Write cycle must be masked by DM.
z Burst Stop Command
The Burst Stop command is initiated by having RAS and CAS High with CS and WE Low at the rising
edge of the clock only. The Burst Stop command has the fewest restrictions, making it the easiest method
to use when terminating a burst operation before it has been completed. When the Burst Stop command is
issued during a Burst Read cycle, both the data and DQS (Data Strobe) go to a high impedance state after
a delay which is equal to the CAS latency set in the Mode Register. The Burst Stop command, however, is
not supported during a Burst Write operation.
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EM68932DVKB
z DM Masking Function
The DDR SDRAM has a Data Mask function that can be used in conjunction with the data write cycle only,
not the read cycle. When the Data Mask is activated (DM High) during a write operation, the write data is
masked immediately (DM to Data Mask latency is zero). DM must be issued at the rising edge or the falling
edge of Data Strobe instead of at a clock edge.
z Auto Precharge Operation
Auto Precharge is a feature which performs the same individual bank precharge function as described
above, but without requiring an explicit command. This is accomplished by using A10 (A10 = High), 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. Auto Precharge is non persistent in that it is either enabled or disabled for each
individual READ or WRITE command. Auto Precharge ensures that a precharge is initiated at the earliest
valid stage within a burst. The user must not issue another command to the same bank until the
precharging time (tRP) is completed. When the Auto Precharge command is activated, the active bank
automatically begins to precharge at the earliest possible moment during a read or write cycle after tRAS
(min) is satisfied.
z Precharge Command
The Precharge command is issued when CS , RAS , and WE are Low and CAS is High at the rising edge
of the clock (CK). The Precharge command can be used to precharge any bank individually or all banks
simultaneously. The Bank Select addresses (BA0, BA1) are used to define which bank is precharged when
the command is initiated. For a write cycle, tWR (min) must be satisfied from the start of the last Burst Write
cycle until the Precharge command can be issued. After tRP from the precharge, an Active command to the
same bank can be initiated.
z Auto Refresh
An Auto Refresh command is issued by having CS , RAS , and CAS held Low with CKE and WE High at
the rising edge of the clock (CK). All banks must be precharged and idle for a tRP (min) before the Auto
Refresh command is applied. The refresh addressing is generated by the internal refresh address counter.
This makes the address bits “Don’t Care" during an Auto Refresh command. When the refresh cycle is
complete, all banks will be in the idle state. A delay between the Auto Refresh command and the next
Active command or subsequent Auto Refresh command must be greater than or equal to the tRFC (min).
z Self Refresh
A Self Refresh command is defined by having CS , RAS , CAS and CKE Low with WE High at the rising
edge of the clock (CK). Once the Self Refresh command has been initiated, CKE must be held Low to keep
the device in Self Refresh mode. During the Self Refresh operation, all inputs except CKE are ignored. The
clock is internally disabled during Self Refresh operation to reduce power consumption. To exit the Self
Refresh mode, supply a stable clock input before returning CKE high, assert Deselect or a NOP command,
and then assert CKE high.
z Power Down Mode
The device enters Power Down mode when CKE is brought Low, and it exits when CKE returns High. Once
the Power Down mode is initiated, all of the receiver circuits except CK and CKE are gated off to reduce
power consumption. All banks should be in an idle state prior to entering the Precharge Power Down mode
and CKE should be set high at least tXP prior to an Active command. During Power Down mode, refresh
operations cannot be performed; therefore the device must remain in Power Down mode for a shorter time
than the refresh period (tREF) of the device.
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z DEEP POWER DOWN
Deep Power Down achieves maximum power reduction by eliminating the power of the whole memory
array and surrounding circuitry. Data will not be retained in the memory storage array, the Mode Register,
or the Extended Mode Register once the device enters Deep Power Down mode.
This mode is entered by having all banks idle then CS and WE held Low with RAS and CAS held High
at the rising edge of the clock, while CKE is Low. This mode is exited by asserting CKE High, applying
only NOP commands for 200 microseconds, and then continuing with steps 4 through 11 of the Power Up
and Initialization sequence..
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Table 8. Absolute Maximum Rating
Rating
Symbol
Parameter
Unit
VIN, VOUT
I/O Pins Voltage
-0.5~2.7
V
VDD, VDDQ
Power Supply Voltage
-0.5~2.7
V
TA
Ambient Temperature
-25~85
°C
TSTG
Storage Temperature
- 55~150
°C
PD
Power Dissipation
0.7
W
-6/75
IOUT
Short Circuit Output Current
50
mA
Note:
1. Stress greater than those listed under “Absolute Maximum Ratings” may cause permanent damage of the
devices.
2. All voltages are referenced to VSS.
3. Functional operation should be restricted to Recommended Operating Conditions.
4. Exposure to higher than the recommended voltages for extended periods of time could affect device
reliability
Table 9. Recommended D.C. Operating Conditions (VDD=1.7V~1.95V, TA =-25~85°C)
Symbol
Min.
Max.
Unit
Power Supply Voltage
Parameter
VDD
1.7
1.95
V
Power Supply Voltage (for I/O Buffer)
VDDQ
1.7
1.95
V
Input High Voltage (DC)
VIH (DC)
0.7 x VDDQ
VDDQ + 0.3
V
Input Low Voltage (DC)
VIL (DC)
-0.3
0.3 x VDDQ
V
Input leakage current
IIL
-2
2
µA
Output leakage current
IOZ
-5
5
µA
Output High Voltage
VOH
0.9 x VDDQ
-
V
Note
IOH=-0.1mA
Output Low Voltage
VOL
0.1 x VDDQ
V
IOL=0.1mA
Note: These parameters are guaranteed by design, periodically sampled and are not 100% tested.
Table 10. Capacitance (VDD=1.7V~1.95V, f = 1MHz, TA = 25 °C)
Symbol
CIN1
Parameter
Input Capacitance (CK, CK )
Min.
Max.
Delta
Unit
1.5
3
0.25
pF
CIN2
Input Capacitance (all other input-only pins )
1.5
3
0.5
pF
CI/O
DQ, DQS, DM Input/Output Capacitance
3
5
0.5
pF
Note: These parameters are guaranteed by design, periodically sampled and are not 100% tested.
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Table 11. D.C. Characteristics (VDD=1.7V~1.95V, TA =-25~85°C)
Parameter & Test Condition
Operating one bank active-precharge current:
tRC=tRC(min); tCK=tCK(min); CKE is HIGH; CS is HIGH between valid
commands; Address inputs are SWITCHING; data bus inputs are STABLE
Precharge power-down standby current:
All banks idle, CKE is LOW; CS is HIGH, tCK=tCK(min);
address and control inputs are SWITCHING; data bus inputs are STABLE
Precharge power-down standby current with clock stop:
All banks idle, CKE is LOW; CS is HIGH, CK = LOW, CK = HIGH;
address and control inputs are SWITCHING; data bus inputs are STABLE
Precharge non power-down standby current:
All banks idle, CKE is HIGH; CS is HIGH, tCK=tCK(min);
address and control inputs are SWITCHING; data bus inputs are STABLE
Precharge non power-down standby current with clock stop:
All banks idle, CKE is HIGH; CS is HIGH, CK = LOW, CK = HIGH;
address and control inputs are SWITCHING; data bus inputs are STABLE
Active power-down standby current:
One bank active, CKE is LOW; CS is HIGH, tCK=tCK(min);
address and control inputs are SWITCHING; data bus inputs are STABLE
Active power-down standby current with clock stop:
One bank active, CKE is LOW; CS is HIGH, CK = LOW, CK = HIGH;
address and control inputs are SWITCHING; data bus inputs are STABLE
Active non power-down standby current:
One bank active, CKE is HIGH; CS is HIGH, tCK=tCK(min) address and
control inputs are SWITCHING; data bus inputs are STABLE
Active non power-down standby current with clock stop:
One bank active, CKE is HIGH; CS is HIGH, CK = LOW, CK = HIGH;
address and control inputs are SWITCHING; data bus inputs are STABLE
Operating burst read current:
One bank active; BL = 4; CL = 3; tCK=tCK(min); continuous read bursts; IOUT =
0 mA address inputs are SWITCHING; 50% data change each burst transfer
Operating burst write current:
One bank active; BL = 4; tCK=tCK(min); continuous write bursts;
address inputs are SWITCHING; 50% data change each burst transfer
Auto-Refresh current:
tRFC = tRFC(min); tCK=tCK(min); burst refresh; CKE is HIGH;
address and control inputs are SWITCHING; data bus inputs are STABLE
Self refresh current:
TCSR Range
CKE is LOW, CK = LOW, CK = HIGH; Extended Mode
Full Array
Register set to all address and control inputs are STABLE;
1/2 Full Array
data bus inputs are STABLE
1/4 Full Array
Deep Power Down Mode Current
-6
Symbol
-75
Max.
Unit
IDD0
45
40
mA
IDD2P
0.1
0.1
mA
IDD2PS
0.1
0.1
mA
IDD2N
15
15
mA
IDD2NS
8
8
mA
IDD3P
3
3
mA
IDD3PS
2
2
mA
IDD3N
20
20
mA
IDD3NS
10
10
mA
IDD4R
150
130
mA
IDD4W
150
130
mA
IDD5
70
70
mA
Max. 40
Max.85
℃
160
200
µA
110
150
µA
90
120
µA
IDD6
IDD8
10
µA
Note:
1. Stress greater than those listed under "Absolute Maximum Ratings" may cause permanent damage of the
device.
2. All voltages are referenced to VSS.
3. These parameters depend on the cycle rate and these values are measured by the cycle rate under the
minimum value of tCK and tRC. Input signals are changed one time per two clock cycles.
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Table 12. Electrical AC Characteristics (VDD=1.7V~1.95V, TA =-25~85°C)
Symbol
-6
Parameter
CL = 2
CL = 3
-75
Unit Note
Min.
12
6
0.45
0.45
Max.
100
0.55
0.55
Min.
12
7.5
0.45
0.45
Max.
100
0.55
0.55
2
5.5
2
6
ns
2
5.5
2
6
ns
2
ns
ns
tCK
tCK
1
tCK
Clock cycle time
tCH
tCL
tDQSCK
Clock high level width
Clock low level width
DQS-out access time from CK, CK
tAC
Output access time from CK, CK
tDQSQ
tRPRE
tRPST
tDQSS
tWPRES
tWPRE
tWPST
tDQSH
tDQSL
DQS-DQ Skew
Read preamble
Read postamble
CK to valid DQS-in
DQS-in setup time
DQS write preamble
DQS write postamble
DQS in high level pulse width
DQS in low level pulse width
0.9
0.4
0.75
0
0.25
0.4
0.4
0.4
0.5
1.1
0.6
1.25
0.6
0.6
0.6
0.9
0.4
0.75
0
0.25
0.4
0.4
0.4
0.6
1.1
0.6
1.25
0.6
0.6
0.6
ns
tCK
tCK
tCK
ns
tCK
tCK
tCK
tCK
3
tIS
Address and Control input setup time
1.1
-
1.3
-
ns
1
tIH
Address and Control input hold time
1.1
-
1.3
-
ns
1
tDS
DQ & DM setup time to DQS
0.6
-
0.8
-
ns
4, 5
tDH
DQ & DM hold time to DQS
0.6
-
0.8
-
ns
4, 5
tHP
Clock half period
-
ns
tQH
Output DQS valid window
-
ns
100K
15.6
ns
ns
ns
ns
ns
ns
ns
tCK
tCK
tCK
tCK
ns
ns
µs
tRC
tRFC
tRAS
tRCD
tRP
tRRD
twR
tDAL
tWTR
tCCD
tMRD
tXSR
tXP
tREFI
Note:
Row cycle time
Refresh row cycle time
Row active time
ACTIVE to READ or WRITE delay
Row precharge time
Row active to Row active delay
Write recovery time
Auto precharge write recovery + Precharge time
Internal Write to Read Delay
Col. Address to Col. Address delay
Mode register set cycle time
Self refresh exit to next valid command delay
Exit Power Down mode to first valid command
Refresh interval time
tCLMIN or
tCHMIN
tHP –
0.65
60
110
42
18
18
12
12
tWR+tRP
2
1
2
200
25
-
tCLMIN or
tCHMIN
tHP –
0.75
67.5
110
45
22.5
22.5
15
15
tWR+tRP
1
1
2
200
25
-
100K
15.6
1
8
7
6
1. Table 13.Input Setup / Hold Slew Rate Derating
Input Setup/Hold Slew Rate (V/ns)
△tIS (ps)
△tIH (ps)
1.0
0
0
0.8
+50
+50
0.6
+100
+100
This derating table is used to increase tIS / tIH in the case where the input slew rate is below 1.0V/ns.
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2. Driver Strength should be selected based on actual system loading conditions. Figure 3, the AC Output
Load Circuit, represents the reference load used in defining the relevant timing parameters of this
device.The 20pF load capacitance is not expected to be a precise representation of either a typical system
load or the production test environment but is appropriate for Full Driver Strength. Setting the output drivers
to 1/2 Driver Strength, for a further example, is appropriate for a 10pF load.
3. The specific requirement is that DQS be Valid (High or Low) on or before this CK edge. 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 at this time, depending on tDQSS.
4. Table 14. I/O Setup / Hold Slew Rate Derating
I/O Setup/Hold Slew Rate (V/ns)
△tDS (ps)
△tDH (ps)
1.0
0
0
0.8
+75
+75
0.6
+150
+150
This derating table is used to increase tDS / tDH in the case where the I/O slew rate is below 1.0V/ns
5. Table 15. I/O Delta Rise / Fall Derating
I/O Delta Rise / Fall Rate (ns/V)
△tDS (ps)
△tDH (ps)
1.0
0
0
±0.25
+50
+50
±0.50
+100
+100
This derating table is used to increase tDS/tDH in the case where the DQ and DQS slew rates differ. The Delta
Rise / Fall Rate is calculated as 1/SlewRate1-1/SlewRate2. For example, if SlewRate1 = 1.0V/ns and
SlewRate2 = 0.8V/ns, then the Delta Rise / Fall Rate = -0.25ns/V.
6. There must be at least one clock (CK) pulse during the tXP period.
7. tWTR is referenced from the positive clock edge after the last Data In pair.
8. tWR is referenced from the positive clock edge after the last desired Data In pair.
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Table 16. Recommended A.C. Operating Conditions (VDD=1.7V~1.95V, TA =-25~85°C)
Parameter
Input High Voltage (AC)
Input Low Voltage (AC)
Symbol
VIH (AC)
Min.
0.8 x VDDQ
VDDQ+0.3
V
1
VIL (AC)
-0.3
0.2 x VDDQ
V
1
0.4 x VDDQ
0.6 x VDDQ
V
2
Input Crossing Point Voltage, CK and CK inputs VIX (AC)
Note:
Max.
Unit Note
1. These parameters should be tested at the pin on actual components and may be checked at either the pin
or the pad in simulation.
2. The value of VIX is expected to equal 0.5 x VDDQ of the transmitting device and must track variation in the DC
level of the same.
Table 17. LVCMOS Interface
Reference Level of Output Signals
0.5 x VDDQ
Output Load
Reference to the Test Load
Input Signal Levels (VIH/ VIL)
0.8 x VDDQ / 0.2 x VDDQ
Input Signals Slew Rate
1 V/ns
Reference Level of Input Signals
0.5 x VDDQ
Figure 4. LVCMOS A.C. Test Load
0.5 x VDDQ
50Ω
Output
Z0=50Ω
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EM68932DVKB
Timing Waveforms
Figure 5. Initialization Waveform Sequence
VDD
VDDQ
200 µS
tCK
tRP
tRFC
tRFC
tMRD
tMRD
CK
CK
CKE
Command
NOP
PRE
ARF
Address
All
Banks
A10
BA0,1
ARF
MRS
MRS
ACT
CODE
CODE
RA
CODE
CODE
RA
BA0=L
BA1=L
BA0=L
BA1=H
BA
DM
DQ,DQS
(High-Z)
VDD / VDDQ powered up
Clock stable
Load
Mode Reg.
Load
Ext. Mode Reg.
Don’t Care
Figure 6. Basic Timing Parameters for Commands
tCK
tCH
tCL
CK
CK
tIS tIH
Input
Valid
Valid
Valid
Don’t Care
Notes: Input = A0 - A11, BA0,BA1, CKE, CS, RAS, CAS, WE;
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Figure 7. NOP Command
CK
CK
CKE
(High)
CS
RAS
CAS
WE
A0-A11
BA0,1
Don’t Care
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Figure 8. Mode Register Set Command
CK
CK
CKE
(High)
CS
RAS
CAS
WE
A0-A11
Code
BA0,1
Code
Don’t Care
Figure 9. Mode Register Set Command Timing
CK
CK
Command
MRS
NOP
Valid
tMRD
Address
Code
Valid
Don’t Care
Notes: Code = Mode Register / Extended Mode Register
selection (BA0, BA1) and op-code (A0- A11)
.
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Figure 10. Active Command
CK
CK
CKE
(High)
CS
RAS
CAS
WE
A0-A11
RA
BA0,1
BA
Don’t Care
BA = Bank Address
RA = Row Address
Figure 11. Bank Activation Command Cycle
CK
CK
Command
ACT
A0-A11
Row
Row
Col
BA0,1
BA x
BA y
BA y
NOP
tRRD
ACT
NOP
NOP
RD/WR
NOP
tRCD
Don’t Care
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Figure 12. Read Command
CK
CK
CKE
(High)
CS
RAS
CAS
WE
A0-A7
CA
Enable AP
A10
AP
Disable AP
BA
BA
Don’t Care
BA = Bank Address
CA = Column Address
AP = Auto Precharge
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Figure 13. Basic Read Timing Parameters
tCK
tCK
tCH
tCL
CK
CK
tDQSCK
tRPRE
tAC max
tDQSCK
tRPST
DQS
tDQSQ max
tHZ
tAC
DQ
DO n
tLZ
DO n+2
tQH
tDQSCK
tRPRE
tRPST
DQS
tDQSQ max
tHZ
tAC
DQ
DO n
tLZ
DO n+1
tQH
(1) DO n = Data Out from column n
(2) All DQ are valid tAC after the CK edge.
All DQ are valid tDQSQ after the DQS edge, regardless of tAC
Etron Confidential
DO n+3
tQH
tDQSCK
tAC min
DO n+1
24
DO n+2
DO n+3
tQH
Don’t Care
Rev. 1.0
Aug. 2009
EtronTech
EM68932DVKB
Figure 14. Read Burst Showing CAS Latency
CK
CK
Command
Address
READ
NOP
NOP
NOP
NOP
NOP
BA, Col n
CL = 2
DQS
DQ
DO n
CL = 3
DQS
DQ
DO n
Don’t Care
(1) DO n = Data Out from column n
(2) BA, Col n = Bank A, Column n
(3) Burst Length = 4; 3 subsequent elements of Data Out appear in the programmed order following DO n
(4) Shown with nominal tAC, tDQSCK and tDQSQ
Figure 15. Consecutive Read Bursts
CK
CK
Command
Address
READ
NOP
BA, Col n
READ
NOP
NOP
NOP
BA, Col b
CL = 2
DQS
DQ
DO n
DO b
CL = 3
DQS
DQ
DO n
DO b
Don’t Care
(1) DO n (or b) = Data Out from column n (or column b)
(2) Burst Length = 4 or 8 (if 4, the bursts are concatenated; if 8 , the second burst interrupts the first)
(3) Read bursts are to an active row in any bank
(4) Shown with nominal tAC, tDQSCK and tDQSQ
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Figure 16. Non-Consecutive Read Bursts
CK
CK
Command
Address
READ
NOP
NOP
READ
BA, Col n
NOP
NOP
BA, Col b
CL = 2
DQS
DQ
DO n
DO b
CL = 3
DQS
DQ
DO n
Don’t Care
(1) DO n (or b) = Data Out from column n (or column b)
(2) BA Col n (b) = Bank A, Column n (b)
(3) Burst Length = 4; 3 subsequent elements of Data Out appear in the programmed order following DO n (b)
(4) Shown with nominal tAC, tDQSCK and tDQSQ
Figure 17. Random Read Bursts
CK
CK
Command
Address
READ
READ
READ
READ
BA, Col n
BA, Col x
BA, Col b
BA, Col g
NOP
NOP
CL = 2
DQS
DQ
DO n
DO n’
DO x
DO x’
DO b
DO b’
DO g
DO g’
DO x’
DO b
DO b’
CL = 3
DQS
DQ
DO n
DO n’
DO x
Don’t Care
(1) DO n, etc. = Data Out from column n, etc.
n’, x’, etc. = Data Out elements, according to the programmed burst order
(2) BA, Col n = Bank A, Column n
(3) Burst Length = 2, 4 or 8 in cases shown (if burst of 4 or 8 , the burst is interrupted)
(4) Reads are to active rows in any banks
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Figure 18. Terminating a Read Burst
CK
CK
Command
Address
READ
BST
NOP
NOP
NOP
NOP
BA, Col n
CL = 2
DQS
DQ
CL = 3
DQS
DQ
Don’t Care
(1) DO n = Data Out from column n
(2) BA Col n = Bank A, Column n
(3) Cases shown are bursts of 4 or 8 teminated after 2 data elements.
(4) Shown with nominal tAC, tDQSCK and tDQSQ
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EtronTech
EM68932DVKB
Figure 19. Read to Write
CK
CK
Command
Address
READ
BST
NOP
WRITE
BA, Col n
NOP
NOP
WRITE
NOP
BA, Col b
CL = 2
tDQSS
DQS
DQ
DO n
DM
Command
Address
READ
BST
NOP
NOP
BA, Col n
BA, Col b
CL = 3
DQS
DQ
DO n
DM
Don’t Care
(1) DO n = Data Out from column n; DI b = Data In to column b
(2) Burst length = 4, 8 in the cases shown; if the burst length is 2, the BST command can be ommitted
(3) Shown with nominal tAC, tDQSCK and tDQSQ
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EtronTech
EM68932DVKB
Figure 20. Read to precharge
CK
CK
Command
READ
Address
NOP
PRE
NOP
NOP
Bank
(a or all)
BA, Col n
ACT
BA, Row
CL = 2
tRP
DQS
DQ
DO n
CL = 3
DQS
DQ
DO n
Don’t Care
(1) DO n = Data Out from column n
(2) Cases shown are either uninterrupted burst of 4, or interrupted bursts of 8.
(3) Shown with nominal tAC, tDQSCK and tDQSQ.
(4) Precharge may be applied at (BL/2) tCK after the READ command.
(5) Note that Precharge may not be issued before tRAS ns after the ACTIVE command for applicable banks.
(6) The ACTIVE command may be applied if tRC has been met.
Figure 21. Burst Terminate Command
CK
CK
CKE
(High)
CS
RAS
CAS
WE
A0-A11
BA0,BA1
Don’t Care
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EtronTech
EM68932DVKB
Figure 22. Write Command
CK
CK
CKE
(High)
CS
RAS
CAS
WE
A0-A7
CA
Enable AP
A10
AP
Disable AP
BA0,1
BA
Don’t Care
BA = Bank Address
CA = Column Address
AP = Auto Precharge
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EtronTech
EM68932DVKB
Figure 23. Basic Write Timing Parameters
tCK
tCH
tCL
CK
CK
tDSH
Case 1:
tDQSS = min
tDQSS
tDSH
tDQSH
tWPST
DQS
tWPRES
tDQSL
tWPRE
tDH
tDS
DQ, DM
DI n
Case 2:
tDQSS = max
tDQSS
tDSS
tDQSH
tDSS
tWPST
DQS
tWPRES
tWPRE
tDH
tDQSL
tDS
DQ, DM
DI n
Don’t Care
(1) DI n = Data In for column n
(2) 3 subsequent elements of Data In are applied in the programmed order following DI n.
(3) tDQSS: each rising edge of DQS must fall within the ±25% window of the corresponding positive clock edge.
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EM68932DVKB
Figure 24. Write Burst (min. and max. tDQSS)
CK
CK
Command
Address
WRITE
NOP
NOP
NOP
NOP
NOP
BA, Col b
tDQSS min
DQS
DQ
DM
tDQSS max
DQS
DQ
DM
Don’t Care
(1) DI b = Data In to column b.
(2) 3 subsequent elements of Data In are applied in the programmed order following DI b.
(3) A non-interrupted burst of 4 is shown.
(4) A10 is LOW with the WRITE command (Auto Precharge is disabled)
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EtronTech
EM68932DVKB
Figure 25. Concatenated Write Bursts
CK
CK
Command
Address
WRITE
NOP
WRITE
BA, Col b
NOP
NOP
NOP
BA, Col n
tDQSS min
DQS
DQ
DI b
DI n
DM
tDQSS max
DQS
DQ
DI b
DI n
DM
Don’t Care
(1) DI b (n) = Data In to column b (column n).
(2) 3 subsequent elements of Data In are applied in the programmed order following DI b.
3 subsequent elements of Data In are applied in the programmed order following DI n.
(3) Non-interrupted bursts of 4 are shown.
(4) Each WRITE command may be to any active bank
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EtronTech
EM68932DVKB
Figure 26. Non-Concatenated Write Bursts
CK
CK
Command
Address
WRITE
NOP
NOP
WRITE
BA, Col b
NOP
NOP
BA, Col n
tDQSS max
DQS
DQ
DM
Don’t Care
(1) DI b (n) = Data In to column b (or column n).
(2) 3 subsequent elements of Data In are applied in the programmed order following DI b.
3 subsequent elements of Data In are applied in the programmed order following DI n.
(3) Non-interrupted bursts of 4 are shown.
(4) Each WRITE command may be to any active bank and may be to the same or different devices
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EtronTech
EM68932DVKB
Figure 27. Random Write Cycles
CK
CK
Command
Address
WRITE
WRITE
WRITE
WRITE
WRITE
BA, Col b
BA, Col x
BA, Col n
BA, Col a
BA, Col g
tDQSS max
DQS
DQ
DI b
DI b
DI x
DI x
DI n
DI n
DI a
DI a
DM
Don’t Care
(1) DI b etc. = Data In to column b, etc. ;
b’, etc. = the next Data In following DI b, etc. according to the programmed burst order
(2) Programmed burst length = 2, 4, or 8 in cases shown. If burst of 4 or 8 , burst would be truncated.
(3) Each WRITE command may be to any active bank and may be to the same or different devices.
Figure 28. Non-Interrupting Write to Read
CK
CK
Command
Address
WRITE
NOP
NOP
NOP
NOP
BA, Col b
READ
NOP
BA, Col n
tWTR
tDQSS max
DQS
DQ
DI b
DM
(1) DI b = Data In to column b.
3 subsequent elements of Data In are applied in the programmed order following DI b.
(2) A non-interrupted burst of 4 is shown.
(3) tWTR is referenced from the positive clock edge after the last Data In pair.
(4) A10 is LOW with the WRITE command (Auto Precharge is disabled)
(5) The READ and WRITE commands are to the same device but not necessarily to the same bank.
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Rev. 1.0
Don’t Care
Aug. 2009
EtronTech
EM68932DVKB
Figure 29. Interrupting Write to Read
CK
CK
Command
Address
WRITE
NOP
NOP
NOP
READ
BA, Col b
NOP
NOP
BA, Col n
tWTR
tDQSS max
CL = 3
DQS
DQ
DI b
DM
(1) DI b = Data In to column b. DO n = Data Out from column n.
(2) An interrupted burst of 4 is shown, 2 data elements are written.
3 subsequent elements of Data In are applied in the programmed order following DI b.
(3) tWTR is referenced from the positive clock edge after the last Data In pair.
(4) A10 is LOW with the WRITE command (Auto Precharge is disabled)
(5) The READ and WRITE commands are to the same device but not necessarily to the same bank.
Don’t Care
Figure 30. Non Interrupting Write to Precharge
CK
CK
Command
Address
WRITE
NOP
NOP
NOP
NOP
PRE
BA a
(or all)
BA, Col b
tDQSS max
tWR
DQS
DQ
DI b
DM
Don’t Care
(1) DI b = Data In to column b.
3 subsequent elements of Data In are applied in the programmed order following DI b.
(2) A non-interrupted burst of 4 is shown.
(3) tWR is referenced from the positive clock edge after the last Data in pair.
(4) A10 is LOW with the WRITE command (Auto Precharge is disabled)
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EtronTech
EM68932DVKB
Figure 31. Interrupting Write to Precharge
CK
CK
Command
Address
WRITE
NOP
NOP
NOP
PRE
NOP
BA a
(or all)
BA, Col b
tWR
tDQSS max
*2
DQS
DQ
DI b
DM
*1
*1
*1
(1) DI b = Data In to column b.
(2) An interrupted burst of 4 or 8 is shown, 2 data elements are written.
(3) tWTR is referenced from the positive clock edge after the last desired Data in pair.
(4) A10 is LOW with the WRITE command (Auto Precharge is disabled)
(5) *1 = can be Don’t Care for programmed burst length of 4
(6) *2 = for programmed burst length of 4, DQS becomes Don’t Care at this point
*1
Don’t Care
Figure 32. Precharge Command
CK
CK
CKE
(High)
CS
RAS
CAS
WE
A0-A9
A11
All Banks
A10
One Bank
BA0,1
BA
Don’t Care
BA = Bank Address
(if A10 = L, otherwise Don’t Care)
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EtronTech
EM68932DVKB
Figure 33. Auto Refresh Command
CK
CK
CKE
(High)
CS
RAS
CAS
WE
A0-A11
BA0,1
Don’t Care
Figure 34. Self Refresh Command
CK
CK
CKE
CS
RAS
CAS
WE
A0-A11
BA0,1
Don’t Care
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EtronTech
EM68932DVKB
Figure 35. Auto Refresh Cycles Back-to-Back
CK
CK
Command
tRP
PRE
tRFC
NOP
ARF
NOP
tRFC
NOP
ARF
NOP
NOP
Ba A,
Row n
Address
A10 (AP)
ACT
Row n
Pre All
High-Z
DQ
Ba A, Row n = Bank A, Row n
Don’t Care
Figure 36. Self Refresh Entry and Exit
CK
CK
tRP
tRFC
tRFC
tXSR
CKE
Command
PRE
NOP
ARF
NOP
NOP
NOP
ARF
DQ
ACT
Ba A,
Row n
Address
A10 (AP)
NOP
Row n
Pre All
High-Z
Enter
Self Refresh
Mode
Exit From
Self Refresh
Mode
Any Command
(Auto Refresh
Recommended)
Don’t Care
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EtronTech
EM68932DVKB
Figure 37. Power-Down Entry and Exit
CK
CK
tRP
tXP
tCKE
CKE
Command
PRE
NOP
NOP
NOP
NOP
NOP
Valid
Address
Valid
A10 (AP)
Valid
Pre All
High-Z
DQ
Power Down
Entry
Exit From
Power Down
Any
Command
Precharge Power-Down mode shown: all banks are idle and tRP is met
when Power-Down Entry command is issued
Don’t Care
Figure 38. Deep Power-Down Entry and Exit
T0
T1
NOP
DPD
Ta0
Ta1
Ta2
NOP
Valid
CK
CK
CKE
Command
Address
Valid
DQS
DQ
DM
tRP
T = 200µs
Enter DPD Mode
Exit DPD Mode
Don’t Care
(1) Clock must be stable before exiting Deep Power-Down mode. That is, the clock must be cycling
within specifications by Ta0
(2) Device must be in the all banks idle state prior to entering Deep Power-Down mode
(3) 200µs is required before any command can be applied upon exiting Deep Power-Down mode
(4) Upon exiting Deep Power-Down mode a PRECHARGE ALL command must be issued, followed
by two AUTO REFRESH commands and a load mode register sequence
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