2M x 16Bits x 4Banks Mobile DDR SDRAM

IS43/46LR16800E
2M x 16Bits x 4Banks Mobile DDR SDRAM
Description
The IS43/46LR16800E is 134,217,728 bits CMOS Mobile Double Data Rate Synchronous DRAM organized as 4 banks of 2,097,152 words x
16 bits. This product uses a double-data-rate architecture to achieve high-speed operation. The Data Input/ Output signals are transmitted
on a 16-bit bus. The double data rate architecture is essentially a 2N prefetch architecture with an interface designed to transfer two data
words per clock cycle at the I/O pins. This product offers fully synchronous operations referenced to both rising and falling edges of the clock.
The data paths are internally pipelined and 2n-bits prefetched to achieve very high bandwidth. All input and output voltage levels are
compatible with LVCMOS.
LVCMOS
Features
• JEDEC standard 1.8V power supply.
• 64ms refresh period (4K cycle)
• VDD = 1.8V, VDDQ = 1.8V
• Auto & self refresh
• Four internal banks for concurrent operation
• Concurrent Auto Precharge
• MRS cycle
y
with address keyy p
programs
g
• Maximum clock frequency
q
y up
p to 166MHZ
- CAS latency 2, 3 (clock)
• Maximum data rate up to 333Mbps/pin
- Burst length (2, 4, 8, 16)
• Special Power Saving supports.
- Burst type (sequential & interleave)
- PASR (Partial Array Self Refresh)
• Fully differential clock inputs (CK, /CK)
- Auto TCSR (Temperature Compensated Self Refresh)
• All inputs except data & DM are sampled at the rising
- Deep Power Down Mode
edge of the system clock
- Programmable Driver Strength Control by Full Strength
• Data I/O transaction on both edges of data strobe
or 1/2, 1/4, 1/8 of Full Strength
• Bidirectional data strobe per byte of data (DQS)
• LVCMOS compatible inputs/outputs
• DM for write masking only
• 60-Ball FBGA package
• Edge aligned data & data strobe output
• Center aligned data & data strobe input
Copyright © 2010 Integrated Silicon Solution, Inc. All rights reserved. ISSI reserves the right to make changes to this specification and its
products at any time without notice. ISSI assumes no liability arising out of the application or use of any information, products or services
described herein. Customers are advised to obtain the latest version of this device specification before relying on any published information
and before placing orders for products.
Integrated Silicon Solution, Inc. does not recommend the use of any of its products in life support applications where the failure or
malfunction of the product can reasonably be expected to cause failure of the life support system or to significantly affect its safety or
effectiveness. Products are not authorized for use in such applications unless Integrated Silicon Solution, Inc. receives written assurance to
its satisfaction, that:
a.) the risk of injury or damage has been minimized;
b.) the user assume all such risks; and
c.) potential liability of Integrated Silicon Solution, Inc is adequately protected under the circumstances
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1
IS43/46LR16800E
Figure1: 60Ball FBGA Ball Assignment
1
2
3
4
5
6
7
8
9
A
VSS
DQ15
VSSQ
VDDQ
DQ0
VDD
B
VDDQ
DQ13
DQ14
DQ1
DQ2
VSSQ
C
VSSQ
DQ11
DQ12
DQ3
DQ4
VDDQ
D
VDDQ
DQ9
DQ10
DQ5
DQ6
VSSQ
E
VSSQ
UDQS
DQ8
DQ7
LDQS
VDDQ
F
VSS
UDM
NC
NC
LDM
VDD
G
CKE
CK
/CK
/WE
/CAS
/RAS
H
A9
A11
NC
/CS
BA0
BA1
J
A6
A7
A8
A10
A0
A1
K
VSS
A4
A5
A2
A3
VDD
[Top View]
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IS43/46LR16800E
Table2 : Pin Descriptions
Symbol
CK, /CK
CKE
/CS
Type
Input
Input
Input
Function
Descriptions
System Clock
The system clock input. CK and /CK are differential clock
inputs. All address and control input signals are registered on
the crossing of the rising edge of CK and falling edge of /CK.
Input and output data is referenced to the crossing of CK and
/CK.
Clock Enable
CKE is clock enable controls input. CKE HIGH activates, and
CKE LOW deactivates internal clock signals, and device input
buffers and output drivers. CKE is synchronous for all functions
exceptt for
f SELF REFRESH EXIT
EXIT, which
hi h is
i achieved
hi
d
asynchronously.
Chip Select
/CS enables (registered Low) and disables (registered High)
the command decoder. All commands are masked when /CS
IS REGISTERED high. /CS provides for external bank selection
on systems with multiple banks. /CS is considered part of the
command code.
BA0, BA1
Input
Bank Address
BA0 and BA1 define to which bank an ACTIVE, READ, WRITE,
or PRECHARGE command is being applied. BA0 and BA1 also
determine which mode register (standard mode register or
extended mode register) is loaded during a LOAD MODE
REGISTER command.
A0~A11
Input
Address
Row Address
Column Address
Auto Precharge
/RAS, /CAS, /WE
Input
Row Address Strobe,
Column Address Strobe,
W it Enable
Write
E bl
/RAS, /CAS and /WE define the operation.
Refer function truth table for details.
Data Input Mask
DM is an input mask signal for write data. Input data
is masked when DM is sampled HIGH along with that input
data during a WRITE access. DM is sampled on both edges of
DQS. Although DM balls are input-only.
: RA0~RA11
: CA0~CA8
: A10
LDM, UDM
Input
DQ0~DQ15
DQ0
DQ15
In/Output
Data Input/Output
Data input/output pin.
LDQS, UDQS
In/Output
Data Input/Output
Strobe
Output with read data, input with write data. DQS is edgealigned with read data, centered in write data. Data strobe is
used to capture data.
VDD
Supply
Power Supply
Power supply
VSS
Supply
Ground
Ground
VDDQ
Supply
DQ Power Supply
Power supply for DQ
VSSQ
Supply
DQ Ground
Ground for DQ
No Connection
No connection.
NC
Rev. A | April 2010
NC
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IS43/46LR16800E
Figure2 : Functional Block Diagram
Self refresh
Logic & timer
Write Data Register
2-bit Prefetch Unit
Internal Row
Counter
X16
Input Bufffer & Logic
PASR
Extended
Mode
Register
X32
2Mx16 BANK 3
Column
Pre
Decoder
|
|
32
|
|
Output Buffer & Logic
LDM/UDM
Memory
Cell
Array
Sense AMP&I/O Gate
Column Active
2Mx16 BANK 0
Row Decoders
/WE
2Mx16 BANK 1
Row
w Decoders
/CAS
Refresh
2Mx16 BANK 2
Row De
ecoders
/RAS
Row
Pre
Decoder
Row Decode
ers
/CS
Row Active
State Machine
M
/CK
CK
CKE
DS
|
|
16
|
|
DQ0
.
.
.
.
.
.
.
DQ15
Column Decoders
Column Add
Counter
Bank Select
UDQS,LDQS
A0
BA0
Address
Register
Burst
Counter
Burst
Length
--------A11
Address Buffers
A1
Mode Register
DS
CAS
Latency
Data Strobe
Transmitter
Data Strobe
Receiver
Data Out Control
BA1
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IS43/46LR16800E
Figure3 : Simplified State Diagram
Power
Applied
DPDSX
Power
On
Deep Power
Down
DPDS
Self
Refresh
Precharge
All Banks
B k
REFSX
REFS
MRS
MRS
EMRS
Idle
All Banks
Precharged
REFA
CKEL
CKEH
ACT
Active
Power
Down
Precharge
Power
Down
CKEH
Row
Active
CKEL
Burst
Stop
WRITE
WRITE
Auto
Refresh
READ
READ A
WRITE A
READ
WRITE
READ
BST
READ
WRITE A
READ A
PRE
WRITE A
PRE
PRE
PRE
Precharge
PREALL
ACT = Active
BST = Burst
CKEL = Enter Power- Down
CKEH = Exit Power-Down
DPDS = Enter Deep Power-Down
DPDSX = Exit Deep Power- Down
EMRS = Ext. Mode Reg. Set
MRS = Mode Register Set
PRE = Precharge
Rev. A | April 2010
READ A
Automatic
sequence
q
PREALL= Precharge All Banks
REFA = Auto Refresh
REFS = Enter Self Refresh
REFSX = Exit Self Refresh
READ = Read w/o Auto Precharge
READ A = Read with Auto Precharge
WRITE = Write w/o Auto Precharge
WRITE A = Write with Auto Precharge
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IS43/46LR16800E
Figure4 : Mode Register Set (MRS) Definition
BA1
A11
BA0
A10
A9
A8
A7
A6
A5
A4
A3
A2
A1
A0
Address Bus
13
12
11
10
9
8
7
0
0
0
0
0
0
0
6
5
4
CAS Latency
3
BT
M6
M5
M4
CAS Latency
M3
Burst Type
0
0
0
Reserved
0
Sequential
0
0
1
Reserved
1
Interleave
0
1
0
0
1
1
1
0
1
2
1
0
Mode Register (Mx)
Burst Length
M2
M1
M0
0
0
2
0
3
0
0
Reserved
0
1
1
1
1
1
Burst Length
M3 = 0
M3 = 1
0
Reserved
Reserved
0
1
2
2
1
0
4
4
0
1
1
8
8
Reserved
1
0
0
16
16
0
Reserved
1
0
1
Reserved
Reserved
1
Reserved
1
1
0
Reserved
Reserved
1
1
1
Reserved
Reserved
Note: M13(BA1) and M12(BA0) must be set to “0” to select Mode Register (vs. the Extended Mode Register)
Burst Type
Accesses within a given burst may be programmed to be either sequential or interleaved; this is referred to as the burst type and is
selected via bit M3. The ordering of accesses within a burst is determined by the burst length, the burst type and the starting column
add ess as shown
address,
sho n in Table 3.
3
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IS43/46LR16800E
Table3 : Burst Definition
Burst Length
2
4
8
16
Starting Column Address
Order of Access within a Burst
A3
A2
A1
A0
Sequential Mode
Interleave Mode
x
x
x
0
0-1
0-1
x
x
x
1
1-0
1-0
x
x
0
0
0-1-2-3
0-1-2-3
x
x
0
1
1-2-3-0
1-0-3-2
x
x
1
0
2-3-0-1
2-3-0-1
x
x
1
1
3-0-1-2
3-2-1-0
x
0
0
0
01234567
0-1-2-3-4-5-6-7
01234567
0-1-2-3-4-5-6-7
x
0
0
1
1-2-3-4-5-6-7-0
1-0-3-2-5-4-7-6
x
0
1
0
2-3-4-5-6-7-0-1
2-3-0-1-6-7-4-5
x
0
1
1
3-4-5-6-7-0-1-2
3-2-1-0-7-6-5-4
x
1
0
0
4-5-6-7-0-1-2-3
4-5-6-7-0-1-2-3
x
1
0
1
5-6-7-0-1-2-3-4
5-4-7-6-1-0-3-2
x
1
1
0
6-7-0-1-2-3-4-5
6
7012345
6-7-4-5-2-3-0-1
6
7452301
x
1
1
1
7-0-1-2-3-4-5-6
7-6-5-4-3-2-1-0
0
0
0
0
0-1-2-3-4-5-6-7-8-9-10-11-12-13-14-15
0-1-2-3-4-5-6-7-8-9-10-11-12-13-14-15
0
0
0
1
1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-0
1-0-3-2-5-4-7-6-9-8-11-10-13-12-15-14
0
0
1
0
2-3-4-5-6-7-8-9-10-11-12-13-14-15-0-1
2-3-0-1-6-7-4-5-10-11-8-9-14-15-12-13
0
0
1
1
3-4-5-6-7-8-9-10-11-12-13-14-15-0-1-2
3-2-1-0-7-6-5-4-11-10-9-8-15-14-13-12
0
1
0
0
4-5-6-7-8-9-10-11-12-13-14-15-0-1-2-3
4-5-6-7-0-1-2-3-12-13-14-15-8-9-10-11
0
1
0
1
5-6-7-8-9-10-11-12-13-14-15-0-1-2-3-4
5-4-7-6-1-0-3-2-13-12-15-14-9-8-11-10
0
1
1
0
6-7-8-9-10-11-12-13-14-15-0-1-2-3-4-5
6-7-4-5-2-3-0-1-14-15-12-13-10-11-8-9
0
1
1
1
7-8-9-10-11-12-13-14-15-0-1-2-3-4-5-6
7-6-5-4-3-2-1-0-15-14-13-12-11-10-9-8
1
0
0
0
8-9-10-11-12-13-14-15-0-1-2-3-4-5-6-7
8-9-10-11-12-13-14-15-0-1-2-3-4-5-6-7
1
0
0
1
9-10-11-12-13-14-15-0-1-2-3-4-5-6-7-8
9-8-11-10-13-12-15-14-1-0-3-2-5-4-7-6
1
0
1
0
10-11-12-13-14-15-0-1-2-3-4-5-6-7-8-9
10-11-8-9-14-15-12-13-2-3-0-1-6-7-4-5
1
0
1
1
11-12-13-14-15-0-1-2-3-4-5-6-7-8-9-10
11-10-9-8-15-14-13-12-3-2-1-0-7-6-5-4
1
1
0
0
12-13-14-15-0-1-2-3-4-5-6-7-8-9-10-11
12-13-14-15-8-9-10-11-4-5-6-7-0-1-2-3
1
1
0
1
13-14-15-0-1-2-3-4-5-6-7-8-9-10-11-12
13-12-15-14-9-8-11-10-5-4-7-6-1-0-3-2
1
1
1
0
14-15-0-1-2-3-4-5-6-7-8-9-10-11-12-13
14-15-12-13-10-11-8-9-6-7-4-5-2-3-0-1
1
1
1
1
15-0-1-2-3-4-5-6-7-8-9-10-11-12-13-14
15-14-13-12-11-10-9-8-7-6-5-4-3-2-1-0
Note :
1. For a burst length of two, A1-A8 select the block of two burst; A0 selects the starting column within the block.
2. For a burst length of four, A2-A8 select the block of four burst; A0-A1 select the starting column within the block.
3. For a burst length of eight, A3-A8 select the block of eight burst; A0-A2 select the starting column within the block.
4. For a burst length of sixteen, A4-A8 select the block of eight burst; A0-A3 select the starting column within the block.
5. Whenever a boundary of the block is reached within a given sequence above, the following access wraps within the block.
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IS43/46LR16800E
Figure5 : Extended Mode Set (EMRS) Register
BA1
BA0
A11
A10
A9
A8
A7
A6
A5
A4
A3
A2
A1
A0
Address Bus
13
12
11
10
9
8
7
1
0
0
0
0
0
0
6
5
DS
4
3
0
0
2
1
0
PASR
Extended Mode Register (Ex)
E6
E5
Driver Strength
E2
E1
E0
Self Refresh Coverage
0
0
Full Strength
0
0
0
Four Banks
0
1
1/2 Strength
0
0
1
Two Bank (BA1=0)
1
0
1/4 Strength
0
1
0
One Bank (BA1=BA0=0)
1
1
1/8 Strength
0
1
1
Reserved
1
0
0
Reserved
1
0
1
One Eighth of Total Bank
(BA1 = BA0 = Row Address MSB=0)
1
1
0
One Sixteenth of Total Bank
(BA1 = BA0 = Row Address 2 MSBs=0)
1
1
1
Reserved
Note: E13(BA1) and E12(BA0) must be set to “1,0” to select Extend Mode Register (vs. the base Mode Register)
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IS43/46LR16800E
Functional Description
The 128Mb Mobile DDR SDRAM is a high-speed
g p
CMOS,, dynamic
y
random-access memoryy containing
g 134,271,728-bits.
,
,
It is internallyy
configured as a quad-bank DRAM. The 128Mb Mobile DDR SDRAM uses a double data rate architecture to achieve high speed operation.
The double data rate architecture is essentially a 2n-prefetch architecture, with an interface designed to transfer two data words per clock
cycle at the I/O 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 the registration of an ACTIVE command, which is then followed by a
READ or WRITE command. The address bits registered coincident with the ACTIVE command are used to select the bank and row to be
accessed (BA0, BA1 select the bank; A0–A11 select the row). The address bits registered coincident with the READ or WRITE command are
used to select the starting column location for the burst access.
It should be noted that the DLL signal that is typically used on standard DDR devices is not necessary on the Mobile DDR SDRAM. It has
been omitted to save power.
Prior to normal operation, the Mobile DDR SDRAM must be powered up and initialized. The following sections provide detailed information
covering device initialization, register definition, command descriptions and device operation.
Power up and Initialization
Mobile DDR SDRAM must be powered up and initialized in a predefined manner. Power must be applied to VDD and VDDQ (simultaneously).
After power up, an initial pause of 200 usec is required. And a precharge all command will be issued to the Mobile DDR. Then, 2 or more
Auto refresh cycles will be provided. After the Auto refresh cycles are completed, a Mode Register Set(MRS) command will be issued to
program the specific mode of operation (Cas Latency, Burst length, etc.) And a Extended Mode Register Set(EMRS) command will be issued
to Partial Array Self Refresh(PASR). The following these cycles, the Mobile DDR SDRAM is ready for normal operation. To ensure device
functionality,
y, there is a p
predefined sequence
q
that must occur at device p
power up
p or if there is anyy interruption
p
of device p
power.
To properly initialize the Mobile DDR SDRAM, this sequence must be followed:
1. To prevent device latch-up, it is recommended the core power (VDD) and I/O power (VDDQ) be from the same power source and brought
up simultaneously. If separate power sources are used, VDD must lead VDDQ.
2. Once power supply voltages are stable and the 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.
7. Using the LOAD MODE REGISTER command, load the standard mode register as desired.
8. Issue NOP or DESELECT commands for at least tMRD time.
9. Using the LOAD MODE REGISTER command, load the extended mode register to the desired operating modes. Note that the order 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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IS43/46LR16800E
Figure6 : Power up sequence
VDD
VDDQ
T0
CLK
/CLK
T1
Ta0
Tb0
Tc0
PCG
AREF
AREF
MRS
Td0
Te0
Tf0
MRS
ACT
NOP3
CODE
RA
CODE
RA
BA0=L,
BA1=H
BA
tCL
LVCMOS
C OS
HIGH LEVEL
CKE
tIS
1
Command
NOP2
tIH
NOP
tIS
A0~A9, A11
tIH
CODE
tIS
All
Banks
A10
tIS
tIH
CODE
tIH
tIS
tIH
BA0=L,
BA1=L
BA0, BA1
High-Z
DQS, DQ
DM
T = 200 µs
tCK
tRP4
Power-up: VDD and CLK stable
tRFC4
Don’ t care
tRFC4
tMRD4
Load Standard Mode
Register
tMRD4
Load Extended Mode
Register
Notes:
1.
PCG = PRECHARGE command, MRS = LOAD MODE REGISTER command, AREF = AUTOREFRESH command,
ACT = ACTIVE command, RA = Row address, BA = Bank address.
2.
NOP or DESELECT commands are required for at least 200μs.
3.
Other valid commands are possible.
4.
NOPs or DESELECTs are required during this time.
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IS43/46LR16800E
Mode Register
The mode register is used to define the specific mode of operation of the Mobile DDR SDRAM. This definition includes the selection of a
burst length, a burst type, a CAS latency. The mode register is programmed via the LOAD MODE REGISTER command and will retain the
stored information until programmed again, the device goes into deep power-down mode, or the device loses power.
Mode register bits A0-A2 specify the burst length, A3 specifies the type of burst (sequential or interleaved), A4-A6 specify the CAS latency,
and A7-A11 should be set to zero. BA0 and BA1 must be zero to access the mode register.
The mode register must be loaded when all banks are idle, and the controller must wait the specified time before initiating the subsequent
operation. Violating either of these requirements will result in unspecified operation.
Burst Length
Read and write accesses to the Mobile DDR SDRAM are burst oriented, with the burst length being programmable, as shown in Figure
(Mode Register Set Definition). The burst length determines the maximum number of column locations that can be accessed for a given
READ or WRITE command. Burst lengths of 2, 4,8 or 16 are available for both the sequential and the interleaved burst types.
Reserved states should not be used, as unknown operation or incompatibility with future versions may result. When a READ or WRITE
command is issued, a block of columns equal to the burst length is effectively selected. All accesses for that burst take place within this
block, meaning that the burst will wrap within the block if a boundary is reached. The block is uniquely selected by A1-A8 when the burst
length is set to two; by A2-A8 when the burst length is set to four; by A3-A8 when the burst length is set to eight; and by A4-A8 when the
burst length is set to sixteen. The remaining (least significant) address bit(s) is (are) used to select the starting location within the block.
The programmed burst length applies to both READ and WRITE bursts.
CAS Latency
The CAS latency is the delay, in clock cycles, between the registration of a READ command and the availability of the first bit of output
data. The latency can be set to 2, 3 clocks, as shown in Figure (Standard Mode Register Definition).
For CL = 3, if the READ command is registered at clock edge n, then the data will be available at (n + 2 clocks + tAC). For CL = 2, if the
READ command is registered at clock edge n, then the data will be available at (n + 1 clock + tAC).
Figure7 : CAS Latency (BL=4)
T0
T1
READ
NOP
T1n
T2
T2n
T3
T3n
T4
T4n
/C L K
C LK
Command
1tCK
NOP
NOP
NOP
tAC
CL=2
tRPRE
tRPST
DQS
D OUT
n
DQ
2tCK
D OUT
n+1
D OUT
n+2
D OUT
n+3
tAC
CL=3
tRPRE
tRPST
DQS
D OUT
n
DQ
DOUT
n+1
D OUT
n+2
DOUT
n+3
Don ’t care
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IS43/46LR16800E
Extended Mode Register
The Extended Mode Register controls the functions beyond those controlled by the Mode Register. These additional functions are special
features of the Mobile DDR SDRAM. They include Partial Array Self Refresh (PASR) and Driver Strength (DS).
The Extended Mode Register is programmed via the Mode Register Set command (BA0=0, BA1=1) and retains the stored information until
programmed again, the device goes into deep power-down mode, or the device loses power.
The Extended Mode Register must be programmed with A7 through A11 set to “0”. The Extended Mode Register must be loaded when all
banks are idle and no bursts are in progress, and the controller must wait the specified time before initiating any subsequent operation.
Violating either of these requirements results in unspecified operation.
Partial Array
y 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 as follows:
• Full array: banks 0, 1, 2, and 3
• Half array: banks 0 and 1
• Quarter array: bank 0
• One eight array: half of bank 0
• One sixteen array: quarter of bank 0
WRITE and READ commands can still occur during standard operation, but only the selected banks will be refreshed during SELF REFRESH.
D t in
Data
i banks
b k that
th t are disabled
di bl d will
ill be
b lost.
l t
Output Driver Strength
Because the Mobile DDR SDRAM is designed for use in smaller systems that are mostly point to point, an option to control the drive
strength of the output buffers is available. Drive strength should be selected based on the expected loading of the memory bus. Bits A5 and
A6 of the extended mode register can be used to select the driver strength of the DQ outputs. There are four allowable settings for the
output drivers.
Temperature Compensated Self Refresh
In the Mobile DDR SDRAM, a temperature sensor is implemented for automatic control of the self refresh oscillator on the device.
Temperature Compensated Self Refresh allows the controller to program the Refresh interval during SELF REFRESH mode, according to the
case temperature of the Mobile SDRAM device. This allows great power savings during SELF REFRESH during most operating temperature
ranges. Only during extreme temperatures would the controller have to select a TCSR level that will guarantee data during SELF REFRESH.
Every cell in the DRAM requires refreshing due to the capacitor losing its charge over time. The refresh rate is dependent on temperature.
At higher temperatures a capacitor loses charge quicker than at lower temperatures, requiring the cells to be refreshed more often.
Historically, during Self Refresh, the refresh rate has been set to accommodate the worst case, or highest temperature range expected.
Thus, during ambient temperatures, the power consumed during refresh was unnecessarily high, because the refresh rate was set to
accommodate the higher temperatures.
This temperature compensated refresh rate will save power when the DRAM is operating at normal temperatures.
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Commands
The following COMMANDS Truth Table and DM Operation Truth Table provide quick reference of available commands. This is followed by a
written description of each command.
Deselect
The DESELECT function (/CS HIGH) prevents new commands from being executed by the Mobile DDR SDRAM. The Mobile DDR SDRAM is
effectively deselected. Operations already in progress are not affected.
NO Operation (NOP)
The NO OPERATION (NOP) command is used to instruct the selected DDR SDRAM to perform a NOP (/CS = LOW, /RAS = /CAS = /WE =
HIGH). This prevents unwanted commands from being registered during idle or wait states. Operations already in progress are not affected.
Active
The ACTIVE command is used to open (or activate) a row in a particular bank for a subsequent access. The value on the BA0, BA1 inputs
selects the bank, and the address provided on inputs A0–A11 selects the row. This row remains active (or open) for accesses until a
PRECHARGE command is issued to that bank. A PRECHARGE command must be issued before opening a different row in the same bank.
Read
The READ command is used to initiate a burst read access to an active row. The value on the BA0, BA1 inputs selects the bank, and the
address provided on inputs A0–A8 selects the starting column location. The value on input A10 determines whether or not auto precharge is
used. If auto precharge is selected, the row being accessed will be precharged at the end of the READ burst; if auto precharge is not
selected, the row will remain open for subsequent accesses.
Write
The WRITE command is used to initiate a burst write access to an active row. The value on the BA0, BA1 inputs selects the bank, and the
address provided on inputs A0-A8 selects the starting column location. The value on input A10 determines whether or not auto precharge is
used If auto precharge is selected
used.
selected, the row being accessed will be precharged at the end of the WRITE burst; if auto precharge is not
selected, the row will remain open for subsequent accesses. Input data appearing on the DQs is written to the memory array subject to the
DM input logic level appearing coincident with the data. If a given DM signal is registered LOW, the corresponding data will be written to
memory; if the DM signal is registered HIGH, the corresponding data inputs will be ignored, and a WRITE will not be executed to that
byte/column location.
Precharge
The PRECHARGE command is used to deactivate the open row in a particular bank or the open row in all banks. The bank(s) will be available
for a subsequent
q
row access a specified
p
time (tRP)
(
) after the precharge
p
g command is issued. Except
p in the case of concurrent auto p
precharge,
g ,
where a READ or WRITE command to a different bank is allowed as long as it does not interrupt the data transfer in the current bank and
does not violate any other timing parameters. Input A10 determines whether one or all banks are to be precharged, and in the case where
only one bank is to be precharged, inputs BA0, BA1select the bank. Otherwise BA0, BA1 are treated as “Don’t Care.” Once a bank has been
precharged, it is in the idle state and must be activated prior to any READ or WRITE commands being issued to that bank. A PRECHARGE
command will be treated as a NOP if there is no open row in that bank (idle state), or if the previously open row is already in the process of
precharging.
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Auto Precharge
Auto precharge is a feature which performs the same individual-bank precharge function described above, but without requiring an explicit
command This is accomplished by using A10 to enable auto precharge in conjunction with a specific READ or WRITE command
command.
command. A
precharge of the bank/row that is addressed with the READ or WRITE command is automatically performed upon completion of the READ or
WRITE burst. Auto precharge is nonpersistent in that it is either enabled or disabled for each individual READ or WRITE command. This
device supports concurrent auto precharge if the command to the other bank does not interrupt the data transfer to the current bank. Auto
precharge ensures that the precharge is initiated at the earliest valid stage within a burst. This “earliest valid stage” is determined as if an
explicit PRECHARGE command was issued at the earliest possible time, without violating tRAS (MIN). The user must not issue another
command to the same bank until the precharge time (tRP) is completed.
Burst Terminate
The BURST TERMINATE command is used to truncate READ bursts (with auto precharge disabled). The most recently registered READ
command prior to the BURST TERMINATE command will be truncated. The open page which the READ burst was terminated from remains
open.
Auto Refresh
AUTO REFRESH is used during normal operation of the Mobile DDR SDRAM and is analogous to /CAS-BEFORE-/RAS (CBR) REFRESH in
FPM/EDO DRAMs. This command is nonpersistent, so it must be issued each time a refresh is required. The addressing is generated by the
internal refresh controller.
controller This makes the address bits a “Don’t Care” during an AUTO REFRESH command.
command The 128Mb Mobile DDR SDRAM
requires AUTO REFRESH cycles at an average interval of 15.6μs (maximum). To allow for improved efficiency in scheduling and switching
between tasks, some flexibility in the absolute refresh interval is provided.
Although not a JEDEC requirement, to provide for future functionality features, CKE must be active (HIGH) during the auto refresh period.
The auto refresh period begins when the AUTO REFRESH command is registered and ends tRFC later.
Self Refresh
The SELF REFRESH command can be used to retain data in the Mobile DDR SDRAM, even if the rest of the system is powered down. When
in the
h self
lf refresh
f h mode,
d the
h Mobile
b l DDR SDRAM retains data
d
without
h
externall clocking.
l k
The
h SELF REFRESH command
d is initiated
d like
l k an
AUTO REFRESH command except CKE is disabled (LOW). All command and address input signals except CKE are “Don’t Care” during SELF
REFRESH.
During SELF REFRESH, the device is refreshed as identified in the external mode register (see PASR setting). For a the full array refresh, all
four banks are refreshed simultaneously with the refresh frequency set by an internal self refresh oscillator. This oscillator changes due to
the temperature sensors input. As the case temperature of the Mobile DDR SDRAM increases, the oscillation frequency will change to
accommodate the change of temperature. This happens because the DRAM capacitors lose charge faster at higher temperatures. To ensure
efficient power dissipation during self refresh, the oscillator will change to refresh at the slowest rate possible to maintain the devices data.
The procedure for exiting SELF REFRESH requires a sequence of commands
commands. First
First, Clock must be stable prior to CKE going back HIGH
HIGH. Once
CKE is HIGH, the Mobile DDR SDRAM must have NOP commands issued for tXSR is required for the completion of any internal refresh in
progress.
Deep Power-down
Deep Power Down is an operating mode to achieve maximum power reduction by eliminating the power of the whole memory array of the
devices. Data will not be retained 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.
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IS43/46LR16800E
Table4: Command Truth Table
Function
/CS
/RAS
/CAS
/WE
BA
A10/AP
ADDR
Note
DESELECT (NOP)
H
X
X
X
X
X
X
2
NO OPERATION (NOP)
L
H
H
H
X
X
X
2
ACTIVE (Select Bank and activate Row)
L
L
H
H
V
Row
Row
READ (Select bank and column and start read burst)
L
H
L
H
V
L
Col
READ with AP (Read Burst with Auto recharge)
L
H
L
H
V
H
Col
WRITE (S
(Select
l tb
bank
k and
d column
l
and
d start
t t write
it b
burst)
t)
L
H
L
L
V
L
C l
Col
WRITE with AP (Write Burst with Auto recharge)
L
H
L
L
V
H
Col
3
BURST TERMINATE or enter DEEP POWER DOWN
L
H
H
L
X
X
X
4,5
PRECHARGE (Deactivate Row in selected bank)
L
L
H
L
V
L
X
6
PRECHARGE ALL (Deactivate rows in all banks)
L
L
H
L
X
H
X
6
AUTO REFRESH or enter SELF REFRESH
L
L
L
H
X
X
X
7,8,9
MODE REGISTER SET
L
L
L
L
V
Op_Code
3
10
Table5 : DM Truth Table
Function
DM
DQ
Note
Write Enable
L
Valid
11
W it Inhibit
Write
I hibit
H
X
11
Note:
1. All states and sequences not shown are illegal or reserved.
2. DESLECT and NOP are functionally interchangeable.
3. Autoprecharge is non-persistent. A10 High enables Autoprecharge, while A10 Low disables Autoprecharge
4. Burst Terminate applies to only Read bursts with autoprecharge disabled.
This command is undefined and should not be used for Read with Autoprecharge enabled, and for Write bursts.
5. This command is BURST TERMINATE if CKE is High and DEEP POWER DOWN entry if CKE is Low.
6. If A10 is low, bank address determines which bank is to be precharged. If A10 is high, all banks are precharged and BA0-BA1 are don‘t
care.
7. This command is AUTO REFRESH if CKE is High, and SELF REFRESH if CKE is low.
8. All address inputs and I/O are ''don't care'' except for CKE. Internal refresh counters control Bank and Row addressing.
9. All banks must be precharged before issuing an AUTO-REFRESH or SELF REFRESH command.
10. BA0 and BA1 value select between MRS and EMRS.
11. Used to mask write data, provided coincident with the corresponding data.
12. CKE is HIGH for all commands shown except SELF REFRESH and DEEP POWER-DOWN.
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Table6 : CKE Truth Table
CKEn 1
CKEn-1
CKEn
Current State
COMMANDn
ACTIONn
L
L
Power Down
X
Maintain Power Down
L
L
Self Refresh
X
Maintain Self Refresh
L
L
Deep Power Down
X
Maintain Deep Power Down
L
H
Power Down
NOP or DESELECT
Exit Power Down
5,6,9
L
H
Self Refresh
NOP or DESELECT
Exit Self Refresh
5,7,10
L
H
Deep Power Down
NOP or DESELECT
Exit Deep Power Down
5,8
H
L
All Banks Idle
NOP or DESELECT
Precharge Power
Down entry
5
H
L
Bank(s) Active
NOP or DESELECT
Active Power Down
Entry
5
H
L
All Banks Idle
AUTO REFRESH
Self Refresh Entry
H
L
All Banks
a s Idle
de
BURST
U S TERMINATE
Enter
te Deep
eep Power
o e
Down
H
H
Note
See the other Truth Tables
Note:
1. CKEn is the logic state of CKE at clock edge n; CKEn-1 was the state of CKE at the previous clock edge.
2. Current state is the state of Mobile DDR immediately prior to clock edge n.
3 COMMANDn
3.
COMMAND is
i the
th command
d registered
i t d att clock
l k edge
d n, and
d ACTIONn is
i the
th result
lt off COMMANDn.
4. All states and sequences not shown are illegal or reserved.
5. DESELECT and NOP are functionally interchangeable.
6. Power Down exit time (tXP) should elapse before a command other than NOP or DESELECT is issued.
7. SELF REFRESH exit time (tXSR) should elapse before a command other than NOP or DESELECT is issued.
8. The Deep Power-Down exit procedure must be followed as discussed in the Deep Power-Down section of the Functional Description.
9. The clock must toggle at least one time during the tXP period.
10. The clock must toggle at least once during the tXSR time.
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Table7 : Current State BANKn Truth Table(COMMAND TO BANK n)
Current State
Any
Idle
Row Active
Read
(without Auto
recharge)
Write
(without Auto
precharge)
Command
Action
Description
Note
/CS
/RAS
/CAS
/WE
H
X
X
X
DESELECT(NOP)
Continue previous Operation
L
H
H
H
NOP
Continue previous Operation
L
L
H
H
ACTIVE
Select and activate row
L
L
L
H
AUTO
U O REFRESH
Auto
u o refresh
10
0
L
L
L
L
MODE REGISTER
SET
Mode register set
10
L
L
H
H
PRECHARGE
No action if bank is idle
L
H
L
H
READ
Select Column & start read burst
L
H
L
L
WRITE
Select Column & start write burst
L
L
H
L
PRECHARGE
Deactivate Row in bank (or banks)
L
H
L
H
READ
Truncate Read & start new Read burst
5,6
L
H
L
L
WRITE
Truncate Read & start new Write burst
5,6,13
L
L
H
L
PRECHARGE
Truncate Read, start Precharge
L
H
H
L
BURST TERMINATE
Burst terminate
L
H
L
H
READ
Truncate Write & start new Read burst
5,6,12
L
H
L
L
WRITE
Truncate Write & start new Write burst
56
5,6
L
L
H
L
PRECHARGE
Truncate Write, start Precharge
12
4
11
Note:
1. The table applies when both CKEn-1 and CKEn are HIGH, and after tXSR or tXP has been met if the previous state was Self Refresh or
Power Down.
2. DESELECT and NOP are functionally interchangeable.
3 All states
3.
t t and
d sequences nott shown
h
are illegal
ill
l or reserved.
d
4. This command may or may not be bank specific. If all banks are being precharged, they must be in a valid state for precharging.
5. A command other than NOP should not be issued to the same bank while a READ or WRITE Burst with auto precharge is enabled.
6. The new Read or Write command could be auto precharge enabled or auto precharge disabled.
7. Current State Definitions:
Idle: The bank has been precharged, and tRP has been met.
Row Active: A row in the bank has been activated, and tRCD has been met.
No data bursts/accesses and no register accesses are in progress.
Read: A READ burst has been initiated, with AUTO PRECHARGE disabled, and has not yet terminated or been terminated.
Write: a WRITE burst has been initiated, with AUTO PRECHARGE disabled, and has not yet terminated or been terminated.
8. The following states must not be interrupted by a command issued to the same bank.
DESELECT or NOP commands or allowable commands to the other bank should be issued on any clock edge occurring during these
states. Allowable commands to the other bank are determined by its current state and Truth Table3, and according to Truth Table 4.
• Precharging: Starts with the registration of a PRECHARGE command and ends when tRP is met.
Once tRP is met, the bank will be in the idle state.
• Row Activating: Starts with registration of an ACTIVE command and ends when tRCD is met.
Once tRCD is met, the bank will be in the ''row active'' state.
• Read with AP Enabled: Starts with the registration of the READ command with AUTO PRECHARGE enabled and ends when tRP has
been met. Once tRP has been met, the bank will be in the idle state.
• Write with AP Enabled: Starts with registration of a WRITE command with AUTO PRECHARGE enabled and ends when tRP has been
met. Once tRP is met, the bank will be in the idle state.
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IS43/46LR16800E
9. The following states must not be interrupted by any executable command; DESELECT or NOP commands must be applied to each
positive clock edge during these states.
states
• Refreshing: Starts with registration of an AUTO REFRESH command and ends when tRFC is met.
Once tRFC is met, the Mobile DDR will be in an ''all banks idle'' state.
• Accessing Mode Register: Starts with registration of a MODE REGISTER SET command and ends when tMRD has been met.
Once tMRD is met, the Mobile DDR will be in an ''all banks idle'' state.
• Precharging All: Starts with the registration of a PRECHARGE ALL command and ends when tRP is met.
Once tRP is met, the bank will be in the idle state.
10. Not bank-specific; requires that all banks are idle and no bursts are in progress.
11. Not bank-specific. BURST TERMINATE affects the most recent READ burst, regardless of bank.
12. Requires appropriate DM masking.
13. A WRITE command may be applied after the completion of the READ burst; otherwise, a Burst terminate must be used to end the
READ prior to asserting a WRITE command.
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IS43/46LR16800E
Table8 : Current State BANKn Truth Table (COMMAND TO BANK m)
Current State
Any
Idle
Row Activating, Active,
or Precharging
Read with Auto Precha
rge disabled
Write with Auto
precharge disabled
Read with Auto
Precharge
Write with Auto
precharge
Rev. A | April 2010
Command
Action
Description
Note
/CS
/RAS
/CAS
/WE
H
X
X
X
DESELECT(NOP)
Continue previous Operation
L
H
H
H
NOP
Continue previous Operation
X
X
X
X
ANY
Any command allowed to bank m
L
L
H
H
ACTIVE
Activate
a Row
o
L
H
L
H
READ
Start READ burst
8
L
H
L
L
WRITE
Start WRITE burst
8
L
L
H
L
PRECHARGE
Precharge
L
L
H
H
ACTIVE
Activate Row
L
H
L
H
READ
State READ burst
8
L
H
L
L
WRITE
Start WRITE burst
8 10
8,10
L
L
H
L
PRECHARGE
Precharge
L
L
H
H
ACTIVE
Activate Row
L
H
L
H
READ
Start READ burst
8,9
L
H
L
L
WRITE
Start WRITE burst
8
L
L
H
L
PRECHARGE
Precharge
L
L
H
H
ACTIVE
Activate Row
L
H
L
H
READ
Start READ burst
5,8
L
H
L
L
WRITE
Start WRITE burst
5,8,10
L
L
H
L
PRECHARGE
Precharge
L
L
H
H
ACTIVE
Activate Row
L
H
L
H
READ
Start READ burst
5,8
L
H
L
L
WRITE
Start WRITE burst
5,8
L
L
H
L
PRECHARGE
Precharge
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Note:
1 The table applies when both CKEn-1
1.
1 and CKEn are HIGH
HIGH, and after tXSR or tXP has been met if the previous state was Self Refresh or
Power Down.
2. DESELECT and NOP are functionally interchangeable.
3. All states and sequences not shown are illegal or reserved.
4. Current State Definitions:
Idle: The bank has been precharged, and tRP has been met.
Row Active: A row in the bank has been activated, and tRCD has been met. No data bursts/accesses and no register accesses are in
progress.
Read: A READ burst has been initiated, with AUTO PRECHARGE disabled, and has not yet terminated or been terminated.
Write: a WRITE burst has been initiated, with AUTO PRECHARGE disabled, and has not yet terminated or been terminated.
5. Read with AP enabled and Write with AP enabled: The read with Autoprecharge enabled or Write with Autoprecharge enabled states
can be broken into two parts: the access period and the precharge period. For Read with AP, the precharge period is defined as if the
same burst was executed with Auto Precharge disabled and then followed with the earliest possible PRECHARGE command that still
accesses all the data in the burst.
For Write with Auto precharge, the precharge period begins when tWR ends, with tWR measured as if Auto Precharge was disabled.
The access period starts with registration of the command and ends where the precharge period (or tRP) begins.
During the precharge period, of the Read with Autoprecharge enabled or Write with Autoprecharge enabled states, ACTIVE,
PRECHARGE, READ, and WRITE commands to the other bank may be applied; during the access period, only ACTIVE and PRECHARGE
commands to the other banks may be applied. In either case, all other related limitations apply
(e.g. contention between READ data and WRITE data must be avoided).
6. AUTO REFRESH, SELF REFRESH, and MODE REGISTER SET commands may only be issued when all bank are idle.
7. A BURST TERMINATE command cannot be issued to another bank;
It applies to the bank represented by the current state only.
8. READs or WRITEs listed in the Command column include READs and WRITEs with AUTO PRECHARGE enabled and READs and WRITEs
with AUTO PRECHARGE disabled.
9. Requires appropriate DM masking.
10. A WRITE command may be applied after the completion of data output, otherwise a BURST TERMINATE command must be issued to
end the READ prior to asserting a WRITE command.
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Table9 : Absolute Maximum Rating
Parameter
Symbol
Rating
Ambient Temperature (Automotive)
Unit
-40 ~ 85
Ambient Temperature (Industrial)
°C
-40 ~ 85
TA
Ambient Temperature (Commercial)
0 ~ 70
TSTG
-55 ~ 150
°C
VIN, VOUT
-0.3 ~ 2.7
V
VDD, VDDQ
-0.3
0.3 ~ 2.7
V
Short Circuit Output Current
IOS
50
mA
Power Dissipation
PD
0.7
W
Storage Temperature
Voltage on Any Pin relative to VSS
Voltage on VDD relative to VSS
Note :
Stresses greater than those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress
rating only, and functional operation of the device at these or any other conditions above those indicated in the operational sections of
this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability.
Table10 : DC Operating Condition
(Voltage referenced to VSS=0V, TA= 0 ~ 70 °C for Commercial, or TA= -40 ~ 85 °C for Industrial or Automotive)
Parameter
Symbol
Min
Typ
Max
Unit
Note
Power Supply Voltage
VDD
1.7
1.8
1.95
V
1
Power Supply Voltage
VDDQ
1.7
1.8
1.95
V
1,2
Input High Voltage
VIH (DC)
0.7 x VDDQ
VDDQ + 0.3
V
Input Low Voltage
VIL (DC)
-0.3
0.3 x VDDQ
V
Output High Voltage
VOH (DC)
0.9 x VDDQ
-
V
IOH=0.1mA
Output Low Voltage
VOL (DC)
-
0.1 x VDDQ
V
IOL=0.1m
A
Input Leakage Current
ILI
-2
2
uA
Output Leakage Current
Note :
ILO
-5
5
uA
1. All Voltages are referenced to VSS = 0V
2. VDD and VDDQ must track each other, and VDDQ must not exceed the level of VDD
Table11 : AC Operating Condition
Parameter
Symbol
Min
Max
Unit
Input High Voltage, all inputs
VIH (AC)
0.8 x VDDQ
VDDQ + 0.3
V
Input Low Voltage, all inputs
VIL (AC)
-0.3
0.2 x VDDQ
V
VIX
0.4 x VDDQ
0.6 x VDDQ
V
Input Crossing Point Voltage, CK and /CK inputs
Note
1
Note :
1. The value of VIX is expected to equal 0.5*VDDQ of the transmitting device and must track variations in the DC level of the same.
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IS43/46LR16800E
Table12 : Capacitance (TA=25 °C, f=1MHz, VDD=1.8V)
Parameter
Input Capacitance
Pin
Symbol
Min
Max
Unit
CK, /CK
CI1
1.5
3.5
pF
A0~A11, BA0~BA1, CKE, /CS, /RAS,
/CAS, /WE
CI2
1.5
3.0
pF
LDM, UDM
CI3
2
4.5
pF
DQ0~DQ15, LDQS, UDQS
CIO
2
4.5
pF
Data & DQS Input/Output Capacitance
Table13 : AC Operating Test Condition
(TA= 0 ~ 70 °C for Commercial, or TA= -40 ~ 85 °C for Industrial or Automotive, VDD = 1.7V to 1.95V, VSS=0V)
Parameter
Symbol
Value
Unit
VIH / VIL
0.8 x VDDQ / 0.2 x VDDQ
V
Input Timing Measurement Reference Level Voltage
VTRIP
0.5 x VDDQ
V
Input Rise / Fall Time
tR / tF
1/1
ns
VOUTREF
0.5 x VDDQ
V
CL
20
pF
AC Input High/Low Level Voltage
Output Timing Measurement Reference Level Voltage
Output Load Capacitance for Access Time Measurement
Figure8 : Output load circuit
VTT=0.5 x VDDQ
VDDQ
13.9KΩ
50Ω
Output
Output
Z0=50Ω
20pF
10.6KΩ
20pF
DC Output Load Circuit
AC Output Load Circuit
Table14 : AC Overshoot/Undershoot Specification
Parameter
Specification
Maximum Peak Amplitude allowed for Overshoot Area
0.9V
Maximum Peak Amplitude allowed for Undershoot Area
0.9V
Maximum Overshoot Area above VDD/VDDQ
3V-ns
Maximum Undershoot Area below VSS/VSSQ
3V-ns
Figure9 : AC Overshoot/Undershoot Definition
Overshoot Area
Maximum Amplitude
Voltage [V]
VDD/VDDQ
VSS/VSSQ
Maximum Amplitude
Undershoot Area
Time [ns]
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IS43/46LR16800E
Table15 : DC Characteristic (DC operating conditions unless otherwise noted)
Parameter
Symbol
y
Test Condition
Speed
-60
-75
-10
55
50
45
Unit
Note
mA
1
Operating one bank activeprecharge current
IDD0
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
IDD2P
All banks idle, CKE is LOW, /CS is HIGH, tCK =
tCK(min), address and control inputs are
SWITCHING, data bus inputs are STABLE
0.3
mA
Precharge power-down standby
current with clock stop
IDD2PS
All banks idle, CKE is LOW, /CS is HIGH, CK = LOW,
/CK = HIGH,
HIGH address and control inputs are
SWITCHING, data bus inputs are STABLE
03
0.3
mA
Precharge non power-down
standby current
IDD2N
All banks idle, CKE is HIGH, /CS is HIGH, tCK =
tCK(min) , address and control inputs are
SWITCHING, data bus inputs are STABLE
9.0
mA
Precharge non power-down
standby current with clock stop
IDD2NS
All banks idle, CKE is HIGH, /CS is HIGH, CK = LOW,
/CK = HIGH, address and control inputs are
SWITCHING, data bus inputs are STABLE
5.0
mA
Active power-down
power down standby
current
IDD3P
One bank active,, CKE is LOW,, //CS is HIGH,, tCK =
tCK(min), address and control inputs are
SWITCHING, data bus inputs are STABLE
5.0
mA
Active power-down standby
current with clock stop
IDD3PS
One bank active, CKE is LOW, /CS is HIGH, CK =
LOW, /CK = HIGH, address and control inputs are
SWITCHING, data bus inputs are STABLE
5.0
mA
Active non power-down
standby current
IDD3N
One bank active, CKE is HIGH, /CS is HIGH, tCK =
tCK(min), address and control inputs are
SWITCHING, data bus inputs are STABLE
20
mA
Active
A
ti non power-down
d
standby current with clock
stop
IDD3NS
O bank
One
b k active,
ti
CKE is
i HIGH,
HIGH /CS is
i HIGH,
HIGH CK =
LOW, /CK = HIGH, address and control inputs are
SWITCHING, data bus inputs are STABLE
10
mA
IDD4R
One bank active, BL=4, CL=3, tCK = tCK(min),
continuous read bursts, IOUT=0mA,
address inputs are SWITCHING, 50% data change
each burst transfer
90
80
70
mA
1
IDD4W
One bank active, BL=4, tCK=tCK(min), continuous
write bursts, address inputs are SWITCHING, 50%
d t change
data
h
each
h burst
b t transfer
t
f
90
80
70
mA
1
mA
2
Operating burst read current
Operating burst write current
Auto Refresh Current
PASR
IDD5
2 Banks
1 Bank
Half
Bank
Quarter
Bank
85°C
350
45°C
300
85°C
45°C
85°C
IDD6
45°C
85°C
CKE is LOW
CK=LOW, /CK=HIGH
tCK=tCK(min)
Extended Mode Register set to all 0's, address and
control inputs are STABLE, data bus inputs are
STABLE
250
210
200
170
155
85°C
165
45°C
150
IDD8
Address and control inputs are STABLE, data bus
inputs are STABLE
uA
175
45°C
Standby Current in
Deep Power Down Mode
Note :
90
TCSR
4 banks
Self
Refresh
Current
tRC=tRFC(min), tCK=tCK(min), burst refresh,
CKE is HIGH, address and control inputs are
SWITCHING, data bus inputs are STABLE
30
uA
1. Measured with outputs open.
2. Refresh period is 64ms.
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IS43/46LR16800E
Table16: AC Characteristic (AC operation conditions unless otherwise noted)
Parameter
System Clock Cycle time
DQ Output access time from CK, /CK
Symbol
CL=3
CL=2
CL=3
CL=2
tCK
tAC
-60
Min
-75
Max
Min
-10
Max
Min
Max
Unit
Note
6
7.5
10
ns
1
10
10
10
ns
1
2.0
5.5
2.0
6.0
2.0
7.0
2.0
8.0
2.0
8.0
2.0
8.0
ns
Clock High pulse width
tCH
0.45
0.55
0.45
0.55
0.45
0.55
tCK
Clock Low pulse width
tCL
0.45
0.55
0.45
0.55
0.45
0.55
tCK
CKE min. pulse width (High/Low pulse width)
tCKE
1
1
1
tCK
DQ and DM Input Setup time
tDS
0.6
0.9
1.2
ns
2, 3, 4
DQ and DM Input Hold time
tDH
0.6
0.9
1.2
ns
2, 3, 4
DQ and DM Input Pulse width
tDIPW
1.8
2.0
2.4
ns
5
Address and Control Input Setup time
tIS
1.1
1.3
1.5
ns
4, 6, 7
Address and Control Input Hold time
tIH
1.1
1.3
1.5
ns
4, 6, 7
Address and Control Input Pulse Width
tIPW
2.7
3.0
3.4
ns
5
DQ & DQS Low
Low-impedance
impedance time from CK
CK, /CK
tLZ
10
1.0
ns
8
DQ & DQS High-impedance time from CK, /CK
tHZ
5.5
6
7
ns
8
DQS - DQ Skew
tDQSQ
0.5
0.6
0.7
ns
9
Half Clock Period
tHP
Data Hold Skew Factor
tQHS
DQ / DQS Output Hold time from DQS
tQH
tHP-tQHS
ns
Write Command to first DQS Latching Transition
tDQSS
0.75
1.25
0.75
1.25
0.75
1.25
tCK
DQS Input
I
t Hi
High
h pulse
l Width
tDQSH
0 35
0.35
06
0.6
04
0.4
06
0.6
04
0.4
06
0.6
tCK
DQS Input Low pulse Width
tDQSL
0.35
0.6
0.4
0.6
0.4
0.6
tCK
DQS Falling Edge to CK Setup Time
tDSS
0.2
0.2
0.2
tCK
DQS Falling Edge Hold Time From CK
tDSH
0.2
0.2
0.2
tCK
Access Window of DQS from CK, /CK
CL=3
CL=2
10
1.0
tCH, tCL
tCH, tCL
0.65
tCH, tCL
0.75
tHP-tQHS
tDQSCK
10
1.0
ns
1
tHP-tQHS
ns
2.0
5.5
2.0
6.0
2.0
7.0
ns
2.0
8.0
2.0
8.0
2.0
8.0
ns
ACTIVE to PRECHARGE Command Period
tRAS
42
45
50
ns
ACTIVE to ACTIVE Command Period
tRC
60
75
80
ns
Mode Register Set command cycle time
tMRD
2
Refresh Period
tREF
64
64
64
ms
Average periodic refresh interval
tREFI
15.6
15.6
15.6
us
Auto Refresh Period
tRFC
70
70
Active to Read or Write delay
tRCD
18
22.5
30
ns
Precharge command period
tRP
18
22.5
30
ns
Active Bank A to Active Bank B Delay
tRRD
12
15
15
ns
Write Recovery time
tWR
12
15
15
ns
Auto Precharge Write Recovery + Precharge time
tDAL
Internal Write to Read Command Delay
tWTR
DQS Read preamble
CL=3
CL=2
tWPRES
tWPST
tCK
1.1
0.9
1.1
tCK
11
0.5
1.1
0.5
1.1
tCK
11
0.6
0.4
0.6
0.4
0.6
tCK
0.4
DQS Write postamble
1
0.9
0.25
DQS Write preamble setup time
1
1.1
tWPRE
Rev. A | April 2010
ns
1.1
tRPST
tXP
70
10
0.5
DQS Write preamble
tXSR
tCK
0.9
DQS Read postamble
Self Refresh Exit to next valid Command Delay
2
(tWR/tCK) + (tRP/tCK)
1
tRPRE
Exit Power Down to next valid command Delay
2
0.25
0
0.4
0.25
0
0.6
0.4
tCK
0
0.6
0.4
0.6
ns
12
tCK
13
1
1
1
tCK
120
120
120
ns
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24
IS43/46LR16800E
Note :
1. The clock frequency must remain constant (stable clock is defined as a signal cycling within timing constraints specified for the
clock pin) during access or precharge states (READ, WRITE, including tDPL, and PRECHARGE commands). CKE may be used to
reduce the data rate.
2. 4. The transition time for DQ, DM and DQS inputs is measured between VIL(DC) to VIH(AC) for rising input signals, and VIH(DC) to
VIL(AC) for falling input signals.
3. DQS, DM and DQ input slew rate is specified to prevent double clocking of data and preserve setup and hold times. Signal transitions
through the DC region must be monotonic.
4 Input slew rate ≥ 0.5V/ns
4.
0 5V/ns and < 1.0V/ns.
1 0V/ns
Input setup/hold slew rate [V/ns]
∆tDS/∆tIS [ps]
∆tDH/∆tIH [ps]
1.0
0
0
0.5
+150
+150
5. These parameters guarantee device timing but they are not necessarily tested on each device.
6. The transition time for address and command inputs is measured between VIH and VIL.
7. A CK,/CK slew rate must be ≥ 1.0V/ns (2.0V/ns if measured differentially) is assumed for this parameter.
CK,/CK setup/hold slew rate [V/ns]
∆tDS/∆tIS [ps]
∆tDH/∆tIH [ps]
1.0
0
0
8. tHZ and tLZ transitions occur in the same access time windows as valid data transitions. These parameters are not referred to a specific
voltage level, but specify when the device is no longer driving (HZ), or begins driving (LZ).
9. tDQSQ consists of data pin skew and output pattern effects, and p-channel to n-channel variation of the output drivers for any given
cycle.
10. A maximum of eight Refresh commands can be posted to any given Low
10
Low-Power
Power DDR SDRAM
SDRAM, meaning that the maximum absolute
interval between any Refresh command and the next Refresh command is 8*tREFI.
11. A low level on DQS may be maintained during High-Z states (DQS drivers disabled) by adding a weak pull-down element in the system.
It is recommended to turn off the weak pull-down element during read and write bursts (DQS drivers enabled).
12. The specific requirement is that DQS be valid (HIGH, LOW, or some point on a valid transition) on or before this CK edge. A valid
transition is defined as monotonic and meeting the input slew rate specifications of the device. When no writes were previously in
progress on the bus, DQS will be transitioning from Hi-Z to logic LOW. If a previous write was in progress, DQS could be HIGH, LOW, or
transitioning from HIGH to LOW at this time, depending on tDQSS.
13. The
13
Th maximum
i
limit
li it for
f this
thi parameter
t is
i nott a device
d i limit.
li it The
Th device
d i operates
t with
ith a greater
t value
l for
f this
thi parameter,
t
but
b t system
t
performance (bus turnaround) will degrade accordingly.
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IS43/46LR16800E
Timing Diagram
B k/
Bank/row
A ti ti
Activation
The Active command is used to activate a row in particular bank for a subsequent Read or Write access. The value of the BA0,BA1 inputs
selects the bank, and the address provided on A0-A11(or the highest address bit) selects the row.
Before any READ or WRITE commands can be issued to a bank within the Mobile DDR SDRAM, a row in that bank must be opened. This
is accomplished via the ACTIVE command, which selects both the bank and the row to be activated. The row remains active until a
PRECHARGE (or READ with AUTO PRECHARGE or WRITE with AUTO PRECHARGE) command is issued to the bank.
A PRECHARGE (or READ with AUTO PRECHARGE or WRITE with AUTO PRECHARGE) command must be issued before opening a different
row in the same bank.
Figure10 : Active command
CLK
/CLK
CKE
/CS
/RAS
Notes :
1. RA : Row address
/CAS
2. BA : Bank address
/WE
A0~A11
RA
BA0, BA1
BA
Don’t care
Once a row is Open(with an ACTIVE command) a READ or WRITE command may be issued to that row, subject to the tRCD specification.
tRCD(min) should be divided by the clock period and rounded up to the next whole number to determine the earliest clock edge after the
ACTIVE command on which a READ or WRITE command can be entered.
A subsequent ACTIVE command to a different row in the same bank can only be issued after the previous active row has been
closed(precharge). The minimum time interval between successive ACTIVE commands to the same bank is defined by tRC. A subsequent
ACTIVE command to another bank can be issued while the first bank is being accessed, which results in a reduction of total row-access
overhead. The minimum time interval between successive ACTIVE commands to different banks is defined by tRRD.
Figure11 : tRCD, tRRD, tRC
T0
T1
T2
T3
T4
Ta0
Ta1
Ta2
RD/WT
with AP
NOP
ACT
NOP
ACT
/CLK
CLK
tIS
tCK
tIH
tCH
tCL
Command
ACT
A0-A11
ROW
COL
ROW
ROW
Bank a
Bank a
Bank b
Bank a
BA0, BA1
NOP
NOP
tRCD
tRRD
tRC
Don’ t care
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IS43/46LR16800E
Read
The READ command is used to initiate a Burst Read to an active row. The value of BA0 and BA1 selects the bank and address inputs select
the starting column location.
The value of A10 determines whether or not auto-precharge is used. If auto-precharge is selected, the row being accessed will be
precharged at the end of the read burst; if auto precharge is not selected, the row will remain open for subsequent access. The valid dataout elements will be available CAS latency after the READ command is issued.
The Mobile DDR drives the DQS during read operations. The initial low state of the DQS is known as the read preamble and the last dataout element is coincident with the read postamble. DQS is edge-aligned with read data. Upon completion of a burst, assuming no new READ
commands have been initiated, the I/O's will go high-Z.
Figure12 : Read command
CLK
/CLK
CKE
/CS
/RAS
/CAS
Notes :
1. CA : Column address
/WE
2. BA : Bank address
A0~A8
CA
3. A10=High : Enable Auto precharge
A10=Low : Disable Auto precharge
A10
BA0 BA1
BA0,
Dont
Don
’ t care
BA
Figure13 : Read Data out timing (BL=4)
T0
T1
READ
NOP
T1n
T2
T2n
T3
T3n
T4
T4n
/CLK
CLK
Command
Address
NOP
NOP
NOP
Bank a
COL n
CL =2
tRPST
tAC
tRPRE
DQS
D OUT
n
DQ
DOUT
n+1
D OUT
n+2
D OUT
n+3
CL=3
tAC
tDQSCK
tRPST
tRPRE
DQS
tDQSQ
D OUT
n
DQ
tLZ
D ’t care
Don’t
D OUT
n+1
tQH
Q
D OUT
n+2
D OUT
n+3
tHZ
Notes:
1. BL=4
2. Shown with nominal tAC, tDQSCK and tDQSQ
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IS43/46LR16800E
Figure14 : Consecutive Read bursts (BL=4)
T0
T1
T2
T3
T4
T5
Command
READ
NOP
READ
NOP
NOP
NOP
Address
Bank a
COL n
/CLK
CLK
Bank a
COL m
CL=3
DQS
DOUT
n
DQ
D OUT
n+1
DOUT
n+2
D OUT
n+3
D OUT
m
D OUT
m +1
Don’ t care
Notes:
1. Dout n or m = Data-Out from Column n or m
2. BL=4,8,16 (if 4, the bursts are concatenated; If 8 or 16, the second burst interrupts the first)
3. Shown with nominal tAC, tDQSCK and tDQSQ
Figure15 : Non-Consecutive
Non Consecutive Read bursts (BL=4)
(BL 4)
T0
T1
T2
T3
T4
T5
Command
READ
NOP
NOP
READ
NOP
NOP
Address
Bank a
COL n
/CLK
CLK
NOP
Bank a
COL m
CL=3
CL=3
DQS
DOUT
n
DQ
D OUT
n+1
DOUT
n+2
D OUT
n+3
D OUT
m
DOUT
m+1
Don ’ t care
Notes:
1. Dout n or m = Data-Out from Column n or m
2. BL=4,8,16 (if 4, the bursts are concatenated; If 8 or 16, the second burst interrupts the first)
3. Shown with nominal tAC, tDQSCK and tDQSQ
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IS43/46LR16800E
Figure16 : Random Read access
T0
T1
T2
T3
T4
T5
Command
READ
READ
READ
READ
NOP
NOP
Address
Bank a
COL n
Bank a
COL m
Bank a
COL p
Bank a
COL q
/CLK
CLK
NOP
CL=3
DQS
DOUT
n
DQ
D OUT
n+1
DOUT
m
D OUT
m+1
D OUT
p
DOUT
p+1
D OUT
q
D OUT
q+1
Don ’ t care
Notes:
1. Dout n or m,p,q = Data-Out from Column n or m,p,q
2. BL=2,4,8,16 (if 4,8 or 16, the following burst interrupts the previous)
3. Reads are to an Active row in any bank.
4. Shown with nominal tAC, tDQSCK and tDQSQ
Truncated Reads
Data from any READ burst may be truncated with a BURST TERMINATE command, as shown in Figure16. The BURST TERMINATE
latency is equal to the READ (CAS) latency, i.e., the BURST TERMINATE command should be issued x cycles after the READ command,
where x equals the number of desired data element pairs (pairs are required by the 2n-prefetch architecture).
Data from any READ burst must be completed or truncated before a subsequent WRITE command can be issued. If truncation is
necessary, the BURST TERMINATE command must be used.
A READ burst may be followed by, or truncated with, a PRECHARGE command to the same bank provided that auto precharge was not
activated. The PRECHARGE command should be issued x cycles after the READ command, where x equals the number of desired data
element pairs (pairs are required by the n-prefetch architecture). This is shown in Figure (READ to PRECHARGE). Following the
PRECHARGE command
command, a subsequent command to the same bank cannot be issued until tRP is met
met.
Figure17 : Read Burst terminate (BL=4,8 or 16)
T0
T1
T2
T3
T4
Command
READ
BST
NOP
NOP
NOP
Address
Bank a
COL n
/CLK
CLK
CL= 3
DQS
DQ
DOUT
n
D OUT
n+ 1
Don’ t care
Notes:
1. Dout n = Data-Out from Column n
2. CKE=high
3. Shown with nominal tAC, tDQSCK and tDQSQ
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IS43/46LR16800E
Figure18 : Read to write terminate (BL=4,8 or 16)
T0
T1
T2
T3
T4
T5
Command
READ
BST
NOP
NOP
WRITE
NOP
Address
Bank a
COL n
/CLK
CLK
Bank a
COL m
CL = 3
tDQSS
Q
(NOM )
DQS
DOUT
n
DQ
D OUT
n+ 1
DIN
m
D IN
m +1
Don’ t care
Notes:
1 Dout n = Data
1.
Data-Out
Out from Column n , Din m = Data
Data-In
In from Column m.
m
2. CKE=high
3. Shown with nominal tAC, tDQSCK and tDQSQ
Figure19 : Read to Precharge (BL=4)
(BL 4)
T0
T1
T2
T3
T4
T5
READ
NOP
PCG
NOP
NOP
ACT
/CLK
CLK
Command
ADDRESS
Bank a
COL n
Bank a
(a, or all )
Bank a
Row
tRP
CL = 3
DQS
DQ
D OUT
n
D OUT
n+ 1
D OUT
n+ 2
D OUT
n+ 3
Don’ t care
Notes:
1. Dout n = Data-Out from Column n.
2. Read to Precharge equals 2 tCK, which allows 2 data pairs of Data-Out.
3. Shown with nominal tAC, tDQSCK and tDQSQ
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IS43/46LR16800E
Write
The WRITE command is used to initiate a Burst Write access to an active row. The value of BA0, BA1 selects the bank and address inputs
select
l t th
the starting
t ti column
l
location.
l
ti
The value of A10 determines whether or not auto precharge is used.If autoprecharge is selected, the row being accessed will be
precharged at the end of the write burst; if auto precharge is not selected, the row will remain open for subsequent access. Input data
appearing on the data bus, is written to the memory array subject to the DM input logic level appearing coincident with the data. If a given
DM signal is registered low, the corresponding data will be written to the memory; if the DM signal is registered high, the corresponding
data-inputs will be ignored, and a write will not be executed to that byte/column location. The memory controller drives the DQS during
write operations. The initial low state of the DQS is known as the write preamble and the low state following the last data-in element is write
postamble. Upon completion of a burst, assuming no new commands have been initiated, the I/O's will stay high-Z and any additional input
data will be ignored.
Figure20 : Write command
CLK
/CLK
CKE
/CS
/RAS
Notes :
1. CA : Column address
/CAS
2. BA : Bank address
3. A10=High : Enable Auto precharge
/WE
A10=Low : Disable Auto precharge
A0~A8
0 8
CA
A10
BA0, BA1
Don’t care
BA
Figure21
g
: Write Burst ((BL=4))
T0
T1
Command
WRITE
NOP
Address
Bank a
COL n
T1n
T2
T2n
T3
/CLK
CLK
WRITE
Bank a
COL m
tDQSS
tDQSH
tWPST
DQS
tWPRES
tWPRE
D IN
n
DQ
tDS
D IN
n+1
tDH
DIN
n+2
D IN
n+3
DM
Don’ t care
Notes:
1. Din n = Data-In from Column n.
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IS43/46LR16800E
Figure22 : Consecutive Write to write (BL=4)
T0
T1
T2
T3
T4
T5
Command
WRITE
NOP
WRITE
NOP
NOP
NOP
Address
Bank a
COL n
/CLK
CLK
Bank a
COL m
tDQSS
Q
(NOM )
DQS
DIN
n
DQ
D IN
n+ 1
DIN
n+ 2
D IN
n+ 3
D IN
m
DIN
m+ 1
D IN
m +2
DIN
m+ 3
DM
Don’t care
Notes:
1. Din n = Data-In from Column n.
2. Each Write command may be to any banks.
Fi
Figure23
23 : Non-Consecutive
N
C
ti Write
W it to
t write
it (BL=4)
(BL 4)
T0
T1
T2
T3
T4
T5
Command
WRITE
NOP
NOP
WRITE
NOP
NOP
Address
Bank a
COL n
/CLK
CLK
NOP
Bank a
COL m
tDQSS
(NOM )
tDQSS
(NOM )
DQS
DQ
D IN
n
D IN
n+ 1
D IN
n+ 2
D IN
n+ 3
D IN
m
DIN
m+ 1
D IN
m +2
DIN
m+ 3
DM
Don’tt care
Don
Notes:
1. Din n = Data-In from Column n.
2. Each Write command may be to any banks.
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IS43/46LR16800E
Figure24 : Random Write to write
T0
T1
T2
T3
T4
Command
WRITE
WRITE
WRITE
WRITE
NOP
Address
Bank a
COL n
Bank a
COL p
Bank a
COL m
Bank a
COL q
/CLK
CLK
tDQSS
(NOM)
DQS
D IN
n
DQ
D IN
n+1
D IN
p
D IN
p+1
D IN
m
DIN
m+1
D IN
q
D IN
q+1
DM
Don’t care
Notes:
1. Din n,p,m,q = Data-In from Column n,p,m,q.
2. Each Write command may be to any banks.
Figure25 : Write to Read (Uninterrupting)
T0
T1
T2
T3
T4
T5
T6
T7
Command
WRITE
NOP
NOP
NOP
READ
NOP
NOP
NOP
Address
Bankk a
B
COL n
/CLK
CLK
B ka
Bank
COL m
tDQSS
(NOM)
tWTR
CL=3
DQS
DQ
D IN
n
D IN
n+1
D IN
n+2
D IN
n+3
D OUT
m
DOUT
m+1
D OUT
m+2
DM
Don’t care
Notes:
1. Din n = Data-In from Column n, Dout m = Data-Out from Column m.
2. tWTR is referenced from the first positive CK edge after the last data-in pair.
3. Read and Write command can be directed to different banks, in which case tWTR is not required and the Read command
could be applied ealier.
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IS43/46LR16800E
Figure26 : Write to Read (Interrupting)
T0
T1
T2
T3
T4
T5
T6
T7
Command
WRITE
NOP
NOP
READ
NOP
NOP
NOP
NOP
Address
Bank a
COL n
/CLK
CLK
Bank a
COL m
tDQSS
(NOM)
tWTR
CL=3
DQS
DIN
n
DQ
D IN
n+1
D OUT
m
DOUT
m+1
D OUT
m+2
DOUT
m+3
DM
Don ’t care
Notes:
1. Din n = Data-In from Column n, Dout m = Data-Out from Column m.
2. tWTR is referenced from the first positive CK edge after the last data-in pair.
Figure27 : Write to Read (Odd number of data Interrupting)
T0
T1
T2
T3
T4
T5
T6
T7
Command
WRITE
NOP
NOP
READ
NOP
NOP
NOP
NOP
Address
Bank a
COL n
/CLK
CLK
Bank a
COL m
tDQSS
(NOM)
tWTR
CL=3
DQS
DQ
DIN
n
D OUT
m
DOUT
m+1
D OUT
m+2
DOUT
m+3
DM
Don’t care
Notes:
1. Din n = Data-In from Column n, Dout m = Data-Out from Column m.
2. tWTR is referenced from the first positive CK edge after the last data-in pair.
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IS43/46LR16800E
Figure28 : Write to Precharge (Uninterrupting)
T0
T1
T2
T3
T4
T5
Command
WRITE
NOP
NOP
NOP
NOP
PCG
Address
Bank a
COL n
/CLK
CLK
tDQSS
(NOM)
tWR
DQS
D IN
n
DQ
D IN
n+1
D IN
n+2
D IN
n+3
DM
Don’t care
Notes:
1. Din n = Data-In from Column n.
2. tWR is referenced from the first positive CK edge after the last data-in pair.
3. Read and Write command can be directed to different banks, in which case tWR is not required and the Read command
could be applied ealier.
Figure29 : Write to Precharge (Interrupting)
T0
T1
T2
T3
T4
T5
Command
WRITE
NOP
NOP
NOP
PCG
NOP
Add
Address
Bank a
COL n
/CLK
CLK
tDQSS
(NOM)
tWR
DQS
D IN
n
DQ
D IN
n+1
DM
Don’ t care
Notes:
1. Din n = Data-In from Column n.
2. tWR is referenced from the first positive CK edge after the last data-in pair.
3. Read and Write command can be directed to different banks, in which case tWR is not required and the Read command
could be applied ealier.
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IS43/46LR16800E
Figure30 : Write to Precharge (Odd number of data Interrupting)
T0
T1
T2
T3
T4
T5
Command
WRITE
NOP
NOP
NOP
PCG
NOP
Address
Bank a
COL n
/CLK
CLK
tDQSS
(NOM)
tWR
DQS
D IN
n
DQ
DM
Don’ t care
Notes:
1. Din n = Data-In from Column n.
2. tWR is referenced from the first positive CK edge after the last data-in pair.
3. Read and Write command can be directed to different banks, in which case tWR is not required and the Read command
could be applied ealier.
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IS43/46LR16800E
Precharge
The Precharge command is used to deactivate the open row in a particular bank or the open row in all banks. The banks will be available
for subsequent row access some specified time (tRP) after the Precharge command issued.
Input A10 determines whether one or all banks are to be precharged. In the case where only one bank is to be precharged (A10=Low),
inputs BA0,BA1 select the banks.
When all banks are to be precharged (A10=High), inputs BA0,BA1 are treated as a “Don’t Care”. Once a bank has been precharged, it is in
the idle state and must be actived prior to any Read or Write commands being issued to that bank.
Figure31 : Precharge command
CLK
/CLK
CKE
/CS
/RAS
/CAS
Notes :
1. BA : Bank address
/WE
A10
BA0, BA1
BA
Don’t care
Mode Register
The mode register contains the specific mode of operation of the Mobile DDR SDRAM. This register includes the selection of a burst length
( 2, 4, 8, 16), a cas latency(2, 3), a burst type. The mode register set must be done before any activate command after the power up
sequence.
Any contents of the mode register be altered by re-programming the mode register through the execution of mode register set command.
Figure32 : Mode Resister Set
/CLK
CLK
CMD
0
1
3
4
Mode
Resister
Set
Precharge
All Bank
tCK
Rev. A | April 2010
2
tRP
5
6
7
8
9
10
Command
(any)
2 CK min
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IS43/46LR16800E
Auto refresh
The Auto refresh command is used during normal operation of the Mobile DDR. It is non persistent, so must be issued each time a refresh
is required. The refresh addressing is generated by the internal refresh controller. The Mobile DDR requires AUTO REFRESH commands at an
average periodic interval of tREFI. To allow for improved efficiency in scheduling and switching between tasks, some flexibility in the
absolute refresh interval is provided. A maximum of eight AUTO REFRESH commands can be posted to any given Mobile DDR, and the
maximum absolute interval between any AUTO REFRESH command and the next AUTO REFRESH command is 8*tREFI.
Figure33 : Auto refresh
T0
T2
T1
T4
T3
Ta0
Ta2
Tb0
Tb0
/CLK
CLK
tIS
tIH
tIS
tIH
tCK
CKE
tCH
tCL
VALID
NOP
Command
PCG
VALID
NOP
NOP
AREF
NOP
AREF
NOP
NOP
A0~A9, A11
ACT
RA
All Banks
A10
RA
One Bank
BA
BA 0, BA 1
BA
DQS, DQ, DM
tRP
Don’t care
tRFC
tRFC
Self refresh
This state retains data in the Mobile DDR, even if the rest of the system is powered down (even without external clocking). Note refresh
interval timing while in Self Refresh mode is scheduled internally in the Mobile DDR and may vary and may not meet tREFI time. "Don't
Care" except CKE, which must remain low. An internal refresh cycle is scheduled on Self Refresh entry. The procedure for exiting Self
Refresh mode requires a series of commands. First clock must be stable before CKE going high. NOP commands should be issued for the
duration of the refresh exit time (tXSR), because time is required for the completion of any internal refresh in progress. The use of SELF
REFRESH mode introduces the possibility that an internally timed event can be missed when CKE is raised for exit from self refresh mode.
mode
Figure34 : Self refresh
T0
T1
Ta0
Ta1
Tb0
/CLK
CLK
tIS
tIH
tIS
tIH
tIS
tIS
CKE
Command
NOP
AREF
NOP
VALID
VALID
Address
DQS, DQ, DM
tRP
Self-refresh mode entry
Rev. A | April 2010
tXSR
Don’t care
Self-refresh mode exit
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IS43/46LR16800E
Power down
Power down occurs if CKE is set low coincident with Device Deselect or NOP command and when no accesses are in progress. If power
down occurs when all banks are idle, it is Precharge Power Down. If Power down occurs when one or more banks are Active, it is referred to
as Active power down. The device cannot stay in this mode for longer than the refresh requirements of the device, without losing data. The
power down state is exited by setting CKE high while issuing a Device Deselect or NOP command. A valid command can be issued after tXP.
Figure35 : Power down (Active or Precharge)
T0
T1
T2
Ta0
Ta1
Tb0
//CLK
CLK
tCK
tIS
tCH
tCL
t XP
tIH
tIS
CKE
tIS
Command
VALID
tIS
Address
tIH
NOP
NOP
VALID
tIH
VALID
VALID
DQS, DQ, DM
Must not exceed refresh device limits
Power-down mode entry
Don’ t care
Power-down mode exit
Deep Power down
The Deep Power-Down (DPD) mode enables very low standby currents. All internal voltage generators inside the Mobile DDR are stopped
and all memory data is lost in this mode. All the information in the Mode Register and the Extended Mode Register is lost. Next Figure, DEEP
POWER-DOWN COMMAND shows the DEEP POWER-DOWN command All banks must be in idle state with no activity on the data bus prior to
entering the DPD mode. While in this state, CKE must be held in a constant low state. To exit the DPD mode, CKE is taken high after the
clock is stable and NOP command must be maintained for at least 200 us.
Figure36 : Deep Power down
T0
T1
T2
Ta0
Ta1
Ta2
Tb 0
/CLK
CLK
tIS
T=200us
tCKE
CKE
Command
NOP
DPD
NOP
Address
NOP
VALID
VALID
DQS, DQ, DM
Deep Power -down mode
entry
Rev. A | April 2010
Deep Power-down mode
exit
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39
IS43/46LR16800E
Clock Stop Mode
Clock stop mode is a feature supported by Mobile DDR SDRAM devices. It reduces clock-related power consumption during idle periods of
the device.
Conditions: the Mobile DDR SDRAM supports clock stop in case:
• The last access command (ACTIVE, READ, WRITE, PRECHARGE, AUTO REFRESH or MODE REGISTER SET) has executed to completion,
including any data-out during read bursts; the number of required clock pulses per access command depends on the device's AC timing
parameters and the clock frequency;
• The related timing condition (tRCD, tWR, tRP, tRFC, tMRD) has been met;
• CKE is held HIGH.
When all conditions have been met, the device is either in ''idle'' or ''row active'' state, and clock stop mode may be entered with CK held
LOW and /CK held HIGH. Clock stop mode is exited when the clock is restarted. NOPs command have to be issued for at least one clock
cycle before the next access command may be applied. Additional clock pulses might be required depending on the system characteristics.
Figure37 illustrates the clock stop mode:
• Initially the device is in clock stop mode;
• The clock is restarted with the rising edge of T0 and a NOP on the command inputs;
• With T1 a valid access command is latched; this command is followed by NOP commands in order to allow for clock stop as soon as this
access command has completed;
• Tn is the last clock pulse required by the access command latched with T1.
• The timing condition of this access command is met with the completion of Tn; therefore Tn is the last clock pulse required by this
command and the clock is then stopped.
stopped
Figure 37 : Clock Stop Mode
T0
/CLK
CLK
CKE
T1
Tn
T2
High
Timing Condition
NOP
CMD
ADD
CMD
NOP
NOP
NOP
Valide
(High – Z)
DQ,DQS
Clock
stopped
Rev. A | April 2010
Exit Clock
Stop Mode
Vail
Command
Enter Clock
Stop Mode
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Don’tt Care
Don
40
IS43/46LR16800E
Ordering Information – VDD = 1.8V
Commercial Range: (0oC to +70oC)
Configuration
Frequency
(MHz)
Speed
(ns)
8Mx16
166
6
Order Part No.
Package
IS43LR16800E-6BL
60-ball BGA, Lead-free
Order Part No.
Package
IS43LR16800E-6BLI
60-ball BGA, Lead-free
Order Part No.
Package
IS46LR16800E-6BLA1
60-ball BGA, Lead-free
Industrial Range: ((-40
40oC to +85oC)
Configuration
Frequency
(MHz)
Speed
(ns)
8Mx16
166
6
Automotive: (-40oC to +85oC)
Configuration
Frequency
(MHz)
Speed
(ns)
8Mx16
166
6
Note: The -6 speed option supports -75 and -10 timing specifications.
Rev. A | April 2010
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IS43/46LR16800E
Rev. A | April 2010
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42