ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 1/45
SDRAM 2M x 16 Bit x 4 Banks
Synchronous DRAM
FEATURES
y JEDEC standard 3.3V power supply
y LVTTL compatible with multiplexed address
y Four banks operation
y MRS cycle with address key programs
- CAS Latency ( 2 & 3 )
- Burst Length ( 1, 2, 4, 8 & full page )
- Burst Type ( Sequential & Interleave )
y All inputs are sampled at the positive going edge of the
system clock
y Burst Read single write operation
y DQM for masking
y Auto & self refresh
y 64ms refresh period (4K cycle)
ORDERING INFORMATION
PRODUCT NO. MAX
FREQ. PACKAGE COMMENTS
M12L128168A-5TG 200MHz 54 Pin TSOP II Pb-free
M12L128168A-5BG 200MHz 54 Ball FBGA Pb-free
M12L128168A-6TG 166MHz 54 Pin TSOP II Pb-free
M12L128168A-6BG 166MHz 54 Ball FBGA Pb-free
M12L128168A-7TG 143MHz 54 Pin TSOP II Pb-free
M12L128168A-7BG 143MHz 54 Ball FBGA Pb-free
GENERAL DESCRIPTION
The M12L128168A is 134,217,728 bits synchronous high data rate Dynamic RAM organized as 4 x 2,097,152 words by 16 bits.
Synchronous design allows precise cycle control with the use of system clock I/O transactions are possible on every clock cycle.
Range of operating frequencies, programmable burst length and programmable latencies allow the same device to be useful for a
variety of high bandwidth, high performance memory system applications.
Pin Arrangement
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 2/45
BLOCK DIAGRAM
PIN DESCRIPTION
PIN NAME INPUT FUNCTION
CLK System Clock Active on the positive going edge to sample all inputs
CS Chip Select
Disables or enables device operation by masking or enabling all
inputs except CLK , CKE and L(U)DQM
CKE Clock Enable
Masks system clock to freeze operation from the next clock cycle.
CKE should be enabled at least one cycle prior new command.
Disable input buffers for power down in standby.
A0 ~ A11 Address Row / column address are multiplexed on the same pins.
Row address : RA0~RA11, column address : CA0~CA8
BA0 , BA1 Bank Select Address Selects bank to be activated during row address latch time.
Selects bank for read / write during column address latch time.
RAS Row Address Strobe Latches row addresses on the positive going edge of the CLK with
RAS low. (Enables row access & precharge.)
CAS Column Address Strobe
Latches column address on the positive going edge of the CLK with
CAS low. (Enables column access.)
WE Write Enable Enables write operation and row precharge.
Latches data in starting from CAS , WE active.
L(U)DQM Data Input / Output Mask Makes data output Hi-Z, tSHZ after the clock and masks the output.
Blocks data input when L(U)DQM active.
DQ0 ~ DQ15 Data Input / Output Data inputs / outputs are multiplexed on the same pins.
V
DD / VSS Power Supply / Ground Power and ground for the input buffers and the core logic.
V
DDQ / VSSQ Data Output Power / Ground Isolated power supply and ground for the output buffers to provide
improved noise immunity.
N.C No Connection This pin is recommended to be left No Connection on the device.
L(U)DQM
DQ
Mode
Register
Control Logic
Column
Address
Buffer
&
Counte
r
Row
Address
Buffer
&
Refresh
Counter
Bank D
Row Decoder
Bank A
Bank B
Bank C
Sense Amplifier
Column Decoder
Data Control Circuit
Latch Circuit
Input & Output
Buffer
Address
Clock
Generator
CLK
CKE
Command Decoder
CS
RAS
CAS
WE
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 3/45
ABSOLUTE MAXIMUM RATINGS
Parameter Symbol Value Unit
Voltage on any pin relative to VSS V
IN, VOUT -1.0 ~ 4.6 V
Voltage on VDD supply relative to VSS V
DD, VDDQ -1.0 ~ 4.6 V
Storage temperature TSTG -55 ~ +150 C°
Power dissipation PD 1 W
Short circuit current IOS 50 mA
Note: Permanent device damage may occur if ABSOLUTE MAXIMUM RATING are exceeded.
Functional operation should be restricted to recommended operating condition.
Exposure to higher than recommended voltage for extended periods of time could affect device reliability.
DC OPERATING CONDITION
Recommended operating conditions (Voltage referenced to VSS = 0V, TA = 0 to 70 C°)
Parameter Symbol Min Typ Max Unit Note
Supply voltage VDD, VDDQ 3.0 3.3 3.6 V
Input logic high voltage VIH 2.0 3.0 VDD+0.3 V 1
Input logic low voltage VIL -0.3 0 0.8 V 2
Output logic high voltage VOH 2.4 - - V IOH = -2mA
Output logic low voltage VOL - - 0.4 V IOL = 2mA
Input leakage current IIL -5 - 5 μA 3
Output leakage current IOL -5 - 5 μA 4
Note: 1. VIH(max) = 4.6V AC for pulse width 10ns acceptable.
2. VIL(min) = -1.5V AC for pulse width 10ns acceptable.
3. Any input 0V V
IN
V
DD, all other pins are not under test = 0V.
4. Dout is disabled, 0V
V
OUT V
DD.
CAPACITANCE (VDD = 3.3V, TA = 25 C°, f = 1MHz)
Parameter Symbol Min Max Unit
Input capacitance (A0 ~ A11, BA0 ~ BA1) CIN1 2.5 4 pF
Input capacitance
(CLK, CKE, CS , RAS , CAS , WE & L(U)DQM)
CIN2 2.5 4 pF
Data input/output capacitance (DQ0 ~ DQ15) COUT 2 6.5 pF
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 4/45
DC CHARACTERISTICS
Recommended operating condition unless otherwise notedTA = 0 to 70 C°
Version
Parameter Symbol Test Condition
-5 -6 -7
Unit Note
Operating Current
(One Bank Active) I
CC1 Burst Length = 1, tRC tRC(min), IOL = 0 mA 170 160 140 mA 1,2
I
CC2P CKE VIL(max), tCC = tCC(min) 2
Precharge Standby Current
in powe
r
-down mode I
CC2PS CKE & CLK
VIL (max), tCC =
2
mA
I
CC2N CKE VIH(min), CS V
IH(min), tCC = tCC(min)
Input signals are changed one time during 2tCC 45
Precharge Standby Current
in non power-down mode
I
CC2NS CKE VIH(min), CLK
VIL(max), tCC =
input signals are stable 25
mA
I
CC3P CKE VIL(max), tCC = tCC(min) 6
Active Standby Current
in powe
r
-down mode I
CC3PS CKE & CLK
VIL(max), tCC =
6
mA
I
CC3N
CKE VIH(min), CS V
IH(min), tCC=15ns
Input signals are changed one time during 2clks
All other pins V
DD-0.2V or 0.2V
55 mA
Active Standby Current
in non powe
r
-down mode
(One Bank Active)
I
CC3NS CKE VIH(min), CLK
VIL(max), tCC =
input signals are stable 35 mA
Operating Current
(Burst Mode) I
CC4 I
OL = 0 mA, Page Burst, 2 Banks activated 280 210 180 mA 1,2
Refresh Current ICC5 tRFC tRFC(min) 280 210 180 mA
Self Refresh Current ICC6 CKE 0.2V 2 mA
Note: 1. Measured with outputs open.
2. Input signals are changed one time during 2 CLKS.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 5/45
AC OPERATING TEST CONDITIONS (VDD = 3.3V
±
0.3V T
A = 0 to 70 C°)
Parameter Value Unit
Input levels (Vih/Vil) 2.4/0.4 V
Input timing measurement reference level 1.4 V
Input rise and fall-time tr/tf = 1/1 ns
Output timing measurement reference level 1.4 V
Output load condition See Fig. 2
(Fig. 1) DC Output Load Circuit (Fig. 2) AC Output Load Circuit
OPERATING AC PARAMETER
(AC operating conditions unless otherwise noted)
Version
Parameter Symbol
-5 -6 -7
Unit Note
Row active to row active delay tRRD(min) 10 12 14
ns 1
RAS to CAS delay t
RCD(min) 15 18 20
ns 1
Row precharge time tRP(min) 15 18 20
ns 1
t
RAS(min) 38 40 42 ns 1
Row active time
t
RAS(max) 100 us
@ Operating tRC(min) 53 58 63 ns 1
Row cycle time
@ Auto refresh tRFC(min) 55 60 70
ns 1,5
Last data in to col. address delay tCDL(min) 1 CLK 2
Last data in to row precharge tRDL(min) 2 CLK 2
Last data in to burst stop tBDL(min) 1 CLK 2
Refresh period (4,096 rows) tREF(max) 64 ms 6
Output
870
VOH (DC) =2.4V , IOH = -2 mA
VOL (DC) =0.4V , IOL = 2 mA Output
50pF
Z0 =50
50pF
50
Vtt = 1.4V
3.3V
1200
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 6/45
Version
Parameter Symbol
-5 -6 -7
Unit Note
Col. address to col. address delay tCCD(min) 1 CLK 3
CAS latency = 3 2
Number of valid
Output data CAS latency = 2 1
ea 4
Note: 1. The minimum number of clock cycles is determined by dividing the minimum time required with clock cycle time and then
rounding off to the next higher integer.
2. Minimum delay is required to complete write.
3. All parts allow every cycle column address change.
4. In case of row precharge interrupt, auto precharge and read burst stop.
5. A new command may be given tRFC after self refresh exit.
6. A maximum of eight consecutive AUTO REFRESH commands (with tRFC(min)) can be posted to any given SDRAM, and
the maximum absolute interval between any AUTO REFRESH command and the next AUTO REFRESH command is
8x15.6 μs.)
AC CHARACTERISTICS (AC operating condition unless otherwise noted)
-5 -6 -7
Parameter Symbol
MIN MAX MIN MAX MIN MAX
Unit Note
CAS latency = 3 5 6 7
CLK cycle time
CAS latency = 2
tCC
10
1000
10
1000
10
1000 ns 1
CAS latency = 3 - 4.5 - 5.4 - 5.4
CLK to valid
output delay CAS latency = 2 tSAC - 6 - 6 - 6 ns 1,2
CAS latency = 3 2 - 2.5 - 2.5 -
Output data
hold time CAS latency = 2 tOH 2 - 2.5 - 2.5 - ns 2
CLK high pulse width tCH 2 - 2.5 - 2.5 - ns 3
CLK low pulse width tCL 2 - 2.5 - 2.5 - ns 3
Input setup time tSS 1.5 - 1.5 - 1.5 - ns 3
Input hold time tSH 1 - 1 - 1 - ns 3
CLK to output in Low-Z tSLZ 1 - 1 - 1 - ns 2
CAS latency = 3 - 5.0 - 5.4 - 5.4
CLK to output
in Hi-Z CAS latency = 2
tSHZ
- 6 - 6 - 6
ns -
Note: 1. Parameters depend on programmed CAS latency.
2. If clock rising time is longer than 1ns. (tr/2 - 0.5) ns should be considered.
3. Assumed input rise and fall time (tr & tf) =1ns.
If tr & tf is longer than 1ns. transient time compensation should be considered.
i.e., [(tr + tf)/2 – 1] ns should be added to the parameter.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 7/45
SIMPLIFIED TRUTH TABLE
COMMAND CKEn-1 CKEn CS RAS CAS WE DQM BA0
BA1 A10/AP A11,
A9~A0 Note
Register Mode Register set H X L L L L X OP CODE 1,2
Auto Refresh H 3
Entry H L L L L H X X 3
L H H H X 3
Refresh Self
Refresh Exit L H H X X X X X 3
Bank Active & Row Addr. H X L L H H X V Row Address
Auto Precharge Disable L 4
Read &
Column Address Auto Precharge Enable
H X L H L H X V
H
Column
Address
(A0~A8) 4,5
Auto Precharge Disable L 4
Write &
Column Address Auto Precharge Enable
H X L H L L X V
H
Column
Address
(A0~A8) 4,5
Burst Stop H X L H H L X X 6
Bank Selection V L
Precharge
All Banks
H X L L H L X
X H
X
H X X X
Entry H L
L V V V
X
Clock Suspend or
Active Power Down
Exit L H X X X X X
X
H X X X
Entry H L
L H H H
X
H X X X
Precharge Power Down Mode
Exit L H
L V V V
X
X
DQM H X V X 7
H X X X
No Operating Command H X
L H H H
X X
(V = Valid, X = Don’t Care. H = Logic High, L = Logic Low)
Note: 1.OP Code: Operating Code
A0~A11 & BA0~BA1: Program keys. (@ MRS)
2.MRS can be issued only at all banks precharge state.
A new command can be issued after 2 CLK cycles of MRS.
3.Auto refresh functions are as same as CBR refresh of DRAM.
The automatical precharge without row precharge of command is meant by “Auto”.
Auto/self refresh can be issued only at all banks idle state.
4.BA0~BA1: Bank select addresses.
If BA0 and BA1 are “Low” at read, write, row active and precharge, bank A is selected.
If BA0 is “Low” and BA1 is “High” at read, write, row active and precharge, bank B is selected.
If BA0 is “High” and BA1 is “Low” at read, write, row active and precharge, bank C is selected.
If BA0 and BA1 are “High” at read, write, row active and precharge, bank D is selected
If A10/AP is “High” at row precharge , BA0 and BA1 is ignored and all banks are selected.
5.During burst read or write with auto precharge, new read/write command can not be issued.
Another bank read/write command can be issued after the end of burst.
New row active of the associated bank can be issued at tRP after the end of burst.
6.Burst stop command is valid at every burst length.
7.DQM sampled at positive going edge of a CLK and masks the data-in at the very CLK (write DQM latency is 0), but
makes Hi-Z state the data-out of 2 CLK cycles after.(Read DQM latency is 2)
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 8/45
MODE REGISTER FIELD TABLE TO PROGRAM MODES
Register Programmed with MRS
Address BA0~BA1 A11~A10/AP A9 A8 A7 A6 A5 A4 A3 A2 A1 A0
Function RFU RFU W.B.L. TM CAS Latency BT Burst Length
Test Mode CAS Latency Burst Type Burst Length
A8 A7 Type A6 A5 A4 Latency A3 Type A2 A1 A0 BT = 0 BT = 1
0 0 Mode Register Set 0 0 0 Reserved 0 Sequential 0 0 0 1 1
0 1 Reserved 0 0 1 Reserved 1 Interleave 0 0 1 2 2
1 0 Reserved 0 1 0 2 0 1 0 4 4
1 1 Reserved 0 1 1 3
0 1 1 8 8
Write Burst Length 1 0 0 Reserved 1 0 0 Reserved Reserved
A9 Length 1 0 1 Reserved 1 0 1 Reserved Reserved
0 Burst 1 1 0 Reserved 1 1 0 Reserved Reserved
1 Single Bit 1 1 1 Reserved
1 1 1 Full Page Reserved
Full Page Length: 512
Note: 1. RFU (Reserved for future use) should stay “0” during MRS cycle.
2. If A9 is high during MRS cycle, “Burst Read single write” function will be enabled.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 9/45
BURST SEQUENCE (BURST LENGTH = 4)
Initial Address
A1 A0
Sequential Interleave
0 0 0 1 2 3 0 1 2 3
0 1 1 2 3 0 1 0 3 2
1 0 2 3 0 1 2 3 0 1
1 1 3 0 1 2 3 2 1 0
BURST SEQUENCE (BURST LENGTH = 8)
Initial Address
A2 A1 A0
Sequential Interleave
0 0 0 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7
0 0 1 1 2 3 4 5 6 7 0 1 0 3 2 5 4 7 6
0 1 0 2 3 4 5 6 7 0 1 2 3 0 1 6 7 4 5
0 1 1 3 4 5 6 7 0 1 2 3 2 1 0 7 6 5 4
1 0 0 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3
1 0 1 5 6 7 0 1 2 3 4 5 4 7 6 1 0 3 2
1 1 0 6 7 0 1 2 3 4 5 6 7 4 5 2 3 0 1
1 1 1 7 0 1 2 3 4 5 6 7 6 5 4 3 2 1 0
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 10/45
DEVICE OPERATIONS
CLOCK (CLK)
The clock input is used as the reference for all SDRAM
operations. All operations are synchronized to the positive
going edge of the clock. The clock transitions must be
monotonic between VIL and VIH. During operation with CKE
high all inputs are assumed to be in valid state (low or high) for
the duration of setup and hold time around positive edge of the
clock for proper functionality and ICC specifications.
CLOCK ENABLE(CKE)
The clock enable (CKE) gates the clock onto SDRAM. If CKE
goes low synchronously with clock (set-up and hold time same
as other inputs), the internal clock suspended from the next
clock cycle and the state of output and burst address is frozen
as long as the CKE remains low. All other inputs are ignored
from the next clock cycle after CKE goes low. When all banks
are in the idle state and CKE goes low synchronously with
clock, the SDRAM enters the power down mode from the next
clock cycle. The SDRAM remains in the power down mode
ignoring the other inputs as long as CKE remains low. The
power down exit is synchronous as the internal clock is
suspended. When CKE goes high at least “1CLK + tSS” before
the high going edge of the clock, then the SDRAM becomes
active from the same clock edge accepting all the input
commands.
BANK ADDRESSES (BA0~BA1)
This SDRAM is organized as four independent banks of
2,097,152 words x 16 bits memory arrays. The BA0~BA1
inputs are latched at the time of assertion of RAS and CAS
to select the bank to be used for the operation. The banks
addressed BA0~BA1 are latched at bank active, read, write,
mode register set and precharge operations.
ADDRESS INPUTS (A0~A11)
The 21 address bits are required to decode the 2,097,152
word locations are multiplexed into 12 address input pins
(A0~A11). The 12 row addresses are latched along with RAS
and BA0~BA1 during bank active command. The 9 bit column
addresses are latched along with CAS , WE and BA0~BA1
during read or with command.
NOP and DEVICE DESELECT
When RAS , CAS and WE are high , The SDRAM
performs no operation (NOP). NOP does not initiate any new
operation, but is needed to complete operations which require
more than single clock cycle like bank activate, burst read,
auto refresh, etc. The device deselect is also a NOP and is
entered by asserting CS high. CS high disables the
command decoder so that RAS , CAS , WE and all the
address inputs are ignored.
POWER-UP
1.Apply power and start clock, Attempt to maintain CKE =
“H”, DQM = “H” and the other pins are NOP condition at
the inputs.
2.Maintain stable power, stable clock and NOP input
condition for minimum of 200us.
3.Issue precharge commands for all banks of the devices.
4.Issue 2 or more auto-refresh commands.
5.Issue a mode register set command to initialize the
mode register.
cf.) Sequence of 4 & 5 is regardless of the order.
The device is now ready for normal operation.
MODE REGISTER SET (MRS)
The mode register stores the data for controlling the
various operating modes of SDRAM. It programs the CAS
latency, burst type, burst length, test mode and various
vendor specific options to make SDRAM useful for variety
of different applications. The default value of the mode
register is not defined, therefore the mode register must
be written after power up to operate the SDRAM. The
mode register is written by asserting low on CS , RAS ,
CAS and WE (The SDRAM should be in active mode
with CKE already high prior to writing the mode register).
The state of address pins A0~A11 and BA0~BA1 in the
same cycle as CS , RAS , CAS and WE going low is
the data written in the mode register. Two clock cycles is
required to complete the write in the mode register. The
mode register contents can be changed using the same
command and clock cycle requirements during operation
as long as all banks are in the idle state. The mode
register is divided into various fields into depending on
functionality. The burst length field uses A0~A2, burst type
uses A3, CAS latency (read latency from column address)
use A4~A6, vendor specific options or test mode use
A7~A8, A10/AP~A11 and BA0~BA1. The write burst
length is programmed using A9. A7~A8, A10/AP~A11 and
BA0~BA1 must be set to low for normal SDRAM
operation. Refer to the table for specific codes for various
burst length, burst type and CAS latencies.
BANK ACTIVATE
The bank activate command is used to select a random
row in an idle bank. By asserting low on RAS and CS
with desired row and bank address, a row access is
initiated. The read or write operation can occur after a
time delay of tRCD(min) from the time of bank activation.
tRCD is the internal timing parameter of SDRAM, therefore
it is dependent on operating clock frequency. The
minimum number of clock cycles required between bank
activate and read or write command should be calculated
by dividing tRCD(min) with cycle time of the clock and then
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 11/45
DEVICE OPERATIONS (Continued)
rounding of the result to the next higher integer. The SDRAM
has four internal banks in the same chip and shares part of the
internal circuitry to reduce chip area, therefore it restricts the
activation of four banks simultaneously. Also the noise
generated during sensing of each bank of SDRAM is high
requiring some time for power supplies to recover before
another bank can be sensed reliably. tRRD(min) specifies the
minimum time required between activating different bank. The
number of clock cycles required between different bank
activation must be calculated similar to tRCD specification. The
minimum time required for the bank to be active to initiate
sensing and restoring the complete row of dynamic cells is
determined by tRAS(min). Every SDRAM bank activate
command must satisfy tRAS(min) specification before a
precharge command to that active bank can be asserted. The
maximum time any bank can be in the active state is
determined by tRAS(max) and tRAS(max) can be calculated
similar to tRCD specification.
BURST READ
The burst read command is used to access burst of data on
consecutive clock cycles from an active row in an active bank.
The burst read command is issued by asserting low on CS
and RAS with WE being high on the positive edge of the
clock. The bank must be active for at least tRCD(min) before the
burst read command is issued. The first output appears in CAS
latency number of clock cycles after the issue of burst read
command. The burst length, burst sequence and latency from
the burst read command is determined by the mode register
which is already programmed. The burst read can be initiated
on any column address of the active row. The address wraps
around if the initial address does not start from a boundary
such that number of outputs from each I/O are equal to the
burst length programmed in the mode register. The output
goes into high-impedance at the end of burst, unless a new
burst read was initiated to keep the data output gapless. The
burst read can be terminated by issuing another burst read or
burst write in the same bank or the other active bank or a
precharge command to the same bank. The burst stop
command is valid at every page burst length.
BURST WRITE
The burst write command is similar to burst read command
and is used to write data into the SDRAM on consecutive clock
cycles in adjacent addresses depending on burst length and
burst sequence. By asserting low on CS , CAS and WE
with valid column address, a write burst is initiated. The data
inputs are provided for the initial address in the same clock
cycle as the burst write command. The input buffer is
deselected at the end of the burst length, even though the
internal writing can be completed yet. The writing can be
complete by issuing a burst read and DQM for blocking data
inputs or burst write in the same or another active bank. The
burst stop command is valid at every burst length. The write
burst can also be terminated by using DQM for blocking data
and precharge the bank tRDL after the last data input to be
written into the active row. See DQM OPERATION also.
DQM OPERATION
The DQM is used mask input and output operations. It
works similar to OE during operation and inhibits writing
during write operation. The read latency is two cycles from
DQM and zero cycle for write, which means DQM masking
occurs two cycles later in read cycle and occurs in the
same cycle during write cycle. DQM operation is
synchronous with the clock. The DQM signal is important
during burst interrupts of write with read or precharge in
the SDRAM. Due to asynchronous nature of the internal
write, the DQM operation is critical to avoid unwanted or
incomplete writes when the complete burst write is
required. Please refer to DQM timing diagram also.
PRECHARGE
The precharge is performed on an active bank by
asserting low on clock cycles required between bank
activate and clock cycles required between bank activate
and CS , RAS , WE and A10/AP with valid BA0~BA1
of the bank to be procharged. The precharge command
can be asserted anytime after tRAS(min) is satisfy from the
bank active command in the desired bank. tRP is defined
as the minimum number of clock cycles required to
complete row precharge is calculated by dividing tRP with
clock cycle time and rounding up to the next higher
integer. Care should be taken to make sure that burst
write is completed or DQM is used to inhibit writing before
precharge command is asserted. The maximum time any
bank can be active is specified by tRAS(max). Therefore,
each bank has to be precharge with tRAS(max) from the
bank activate command. At the end of precharge, the
bank enters the idle state and is ready to be activated
again. Entry to power-down, Auto refresh, Self refresh and
Mode register set etc. is possible only when all banks are
in idle state.
AUTO PRECHARGE
The precharge operation can also be performed by using
auto precharge. The SDRAM internally generates the
timing to satisfy tRAS(min) and “tRP” for the programmed
burst length and CAS latency. The auto precharge
command is issued at the same time as burst write by
asserting high on A10/AP, the bank is precharge command
is asserted. Once auto precharge command is given, no
new commands are possible to that particular bank until
the bank achieves idle state.
FOUR BANKS PRECHARGE
Four banks can be precharged at the same time by using
Precharge all command. Asserting low on CS , RAS ,
and WE with high on A10/AP after all banks have
satisfied tRAS(min) requirement, performs precharge on all
banks. At the end of tRP after performing precharge all, all
banks are in idle state.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 12/45
DEVICE OPERATIONS (Continued)
AUTO REFRESH
The storage cells of SDRAM need to be refreshed every 64ms
to maintain data. An auto refresh cycle accomplishes refresh of
a single row of storage cells. The internal counter increments
automatically on every auto refresh cycle to refresh all the
rows. An auto refresh command is issued by asserting low on
CS , RAS and CAS with high on CKE and WE . The auto
refresh command can only be asserted with all banks being in
idle state and the device is not in power down mode (CKE is
high in the previous cycle). The time required to complete the
auto refresh operation is specified by tRFC(min). The minimum
number of clock cycles required can be calculated by driving
tRFC with clock cycle time and them rounding up to the next
higher integer. The auto refresh command must be followed by
NOP’s until the auto refresh operation is completed. The auto
refresh is the preferred refresh mode when the SDRAM is
being used for normal data transactions. The auto refresh
cycle can be performed once in 15.6us.
SELF REFRESH
The self refresh is another refresh mode available in the
SDRAM. The self refresh is the preferred refresh mode for
data retention and low power operation of SDRAM. In self
refresh mode, the SDRAM disables the internal clock and
all the input buffers except CKE. The refresh addressing
and timing is internally generated to reduce power
consumption.
The self refresh mode is entered from all banks idle state
by asserting low on CS , RAS , CAS and CKE with
high on WE . Once the self refresh mode is entered, only
CKE state being low matters, all the other inputs including
clock are ignored to remain in the refresh.
The self refresh is exited by restarting the external clock
and then asserting high on CKE. This must be followed by
NOP’s for a minimum time of tRFC before the SDRAM
reaches idle state to begin normal operation. 4K cycles of
burst auto refresh is required immediately before self
refresh entry and immediately after self refresh exit.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 13/45
COMMANDS
Mode register set command
(
CS , RAS , CAS , WE = Low)
The M12L128168A has a mode register that defines how the device operates. In
this command, A0~A11 and BA0~BA1 are the data input pins. After power on, the
mode register set command must be executed to initialize the device.
The mode register can be set only when all banks are in idle state.
During 2CLK following this command, the M12L128168A cannot accept any
other commands.
Activate command
(
CS , RAS = Low, CAS , WE = High)
The M12L128168A has four banks, each with 4,096 rows.
This command activates the bank selected by BA1 and BA0 (BS) and a row
address selected by A0 through A11.
This command corresponds to a conventional DRAM’s RAS falling.
Precharge command
(
CS , RAS , WE = Low, CAS = High )
This command begins precharge operation of the bank selected by BA1 and BA0
(BS). When A10 is High, all banks are precharged, regardless of BA1 and BA0.
When A10 is Low, only the bank selected by BA1 and BA0 is precharged.
After this command, the M12L128168A can’t accept the activate command to the
precharging bank during tRP (precharge to activate command period).
This command corresponds to a conventional DRAM’s RAS rising.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 14/45
Write command
(CS , CAS , WE = Low, RAS = High)
If the mode register is in the burst write mode, this command sets the burst start
address given by the column address to begin the burst write operation. The first
write data in burst can be input with this command with subsequent data on following
clocks.
Read command
(CS , CAS = Low, RAS , WE = High)
Read data is available after CAS latency requirements have been met.
This command sets the burst start address given by the column address.
CBR (auto) refresh command
(CS , RAS , CAS = Low, WE , CKE = High)
This command is a request to begin the CBR refresh operation. The refresh
address is generated internally.
Before executing CBR refresh, all banks must be precharged.
After this cycle, all banks will be in the idle (precharged) state and ready for a
row activate command.
During tRFC period (from refresh command to refresh or activate command), the
M12L128168A cannot accept any other command.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 15/45
Self refresh entry command
(CS , RAS , CAS , CKE = Low , WE = High)
After the command execution, self refresh operation continues while CKE
remains low. When CKE goes to high, the M12L128168A exits the self refresh mode.
During self refresh mode, refresh interval and refresh operation are performed
internally, so there is no need for external control.
Before executing self refresh, all banks must be precharged.
Burst stop command
(
CS , WE = Low, RAS , CAS = High)
This command terminates the current burst operation.
Burst stop is valid at every burst length.
No operation
(
CS = Low , RAS , CAS , WE = High)
This command is not a execution command. No operations begin or terminate by
this command.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 16/45
BASIC FEATURE AND FUNCTION DESCRIPTIONS
1. CLOCK Suspend
2. DQM Operation
*Note: 1. CKE to CLK disable/enable = 1CLK.
2. DQM masks data out Hi-Z after 2CLKs which should masked by CKE ”L”.
3. DQM masks both data-in and data-out.
CLK
CMD
DQM
DQ(CL2)
DQ(CL3)
RD
Q0 Q2 Q3
Q1 Q2 Q3D0 D1 D3
D1 D3
D0
WR
Masked by DQM
Masked by DQM
CLK
CMD
DQM
DQ(CL2)
DQ(CL3)
CKE
RD
Q0 Q2 Q4
Hi-Z Hi-Z Hi-Z Q6 Q7 Q8
Q5 Q6 Q7
Q1 Q3
Hi-Z Hi-Z Hi-Z
Hi-Z
Hi-Z
1)Write Mask (BL=4) 2)Read Mask (BL=4)
DQM to Data-in Mask=0 DQM to Data-out Mask=2
3)DQM with clcok su spended (Full Page Read)
*Note2
Internal
CLK
CLK
CMD
CKE
Internal
CLK
DQ(CL2)
DQ(CL3)
RD
Q2
Q0 Q1 Q3
Q2 Q0
Q1 Q3
D0 D1 D2 D3
D1 D2 D3
D0
WR
Masked by CKE
1) Clock Suspended During Write (BL=4) 2) Clock Suspended During Read (BL=4)
Not Written Suspended Dout
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 17/45
3. CAS Interrupt (I)
CLK
CMD
ADD
DQ(CL2)
DQ(CL3)
RD
QB0 QB2QA0
CLK
CMD
ADD
DQ
WR
DA0 DB0 DB1
RD
AB
QB1 QB3
QB0 QB2
QA0 QB3QB1
tCCD
*Not e 2
WR
tCC D * No te 2
AB
tCDL
*Note 3
WR RD
tCCD *Note 2
A B
DA0 DB0 DB1
tCDL
*Note 3
DA0 DB0 DB1
DQ(CL3)
DQ (C L2 )
1)Read interrupted by Read (BL=4)
2) Wr i te in ter ru pt e d b y W ri te (B L= 2) 3 )W ri te in ter rup ted by R ead (B L=2 )
*No
t
e1
*Note: 1. By “interrupt” is meant to stop burst read/write by external before the end of burst.
By ” CAS interrupt ”, to stop burst read/write by CAS access ; read and write.
2. tCCD:CAS to CAS delay. (=1CLK)
3. tCDL: Last data in to new column address delay. (=1CLK)
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 18/45
4. CAS Interrupt (II): Read Interrupted by Write & DQM
CLK
i)CMD
DQM
DQ D1 D3
D0 D2
WR
ii)CMD
DQM
DQ
iii)CMD
DQM
DQ
iv)CMD
DQM
DQ
D1 D3
D0 D2
RD WR
RD WR
D1 D3D0 D2
D1 D3D0 D2
RD WR
Hi-Z
Q0
*Note1
Hi-Z
Hi-Z
Hi-Z
(a)CL=2,BL=4
RD
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 19/45
*Note: 1. To prevent bus contention, there should be at least one gap between data in and data out.
5. Write Interrupted by Precharge & DQM
CLK
CMD
DQM
DQ D0 D1
WR
*Note3
*Note2
Masked by DQM
D3
PRE
t
RDL(min)
*Note: 1. To prevent bus contention, DQM should be issued which makes at least one gap between data in and data out.
2. To inhibit invalid write, DQM should be issued.
3. This precharge command and burst write command should be of the same bank, otherwise it is not precharge interrupt
but only another bank precharge of four banks operation.
CLK
i)CMD
ii)CMD
iii)CMD
iv)CMD
DQM
DQM
DQM
DQM
DQ
DQ
DQ
DQ
D1 D3
D1
D0 D2
D3
D0 D2
WR
(b)CL=3,BL=4
RD WR
RD WR
D1 D3
D0 D2
D1 D3
D0 D2
RD WR
Hi-Z
D1 D3
D0 D2
Q0
*Note1
v)CMD
DQM
DQ
RD WR
Hi-Z
RD
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 20/45
6. Precharge
.
7. Auto Precharge
*Note: 1. tRDL: Last data in to row precharge delay.
2. Number of valid output data after row precharge: 1, 2 for CAS Latency = 2, 3 respectively.
3. The row active command of the precharge bank can be issued after tRP from this point.
The new read/write command of other activated bank can be issued from this point.
At burst read/write with auto precharge, CAS interrupt of the same/another bank is illegal.
CLK
CMD
DQ D0 D1 D2 D3
WR
tRDL
*Note1
CLK
CMD
CMD
DQ(CL2) Q0 Q1 Q2 Q3
RD PRE
DQ(CL3) Q0 Q1 Q2 Q3
PRE
1)No
r
mal W
r
ite (BL=4) 2)Normal Read (BL=4)
CL=2
PRE CL=3
*Note2
*Note2
CLK
CMD
DQ D0 D1 D2 D3
WR
CLK
CMD
DQ(CL2) D0 D1 D2 D3
RD
DQ(CL3)
*Note3
Auto Precharge starts
D0 D1 D2 D3
*Note3
Auto Precharge starts
1
)
No
r
mal W
r
ite
(
BL=4
)
2
)
No
r
mal Read
(
BL=4
)
tRDL (min)
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 21/45
8. Burst Stop & Interrupted by Precharge
CLK
CMD
DQ(CL2)
DQ(CL3)
CLK
CMD
DQM
DQ
Q0 Q1
Q0 Q1
RD STOP
*Note2
1)W
r
ite B
u
r
st St
o
p(B
L
=
8
)
2)Read Burst Stop (BL=4)
CLK
CMD
DQ(CL2)
CLK
CMD
DQM
DQ D0 D1 Mask Mask
WR
1)W
r
ite i
n
te
r
r
u
pte
d
b
y
p
r
ec
h
a
r
g
e(B
L
=
4
)
2)Read interrupted by precharge (BL=4)
*Note2
PRE
*Note4
*Note3
DQ(CL3)
*Note5
t
RDL
Q2
Q3
Q0 Q1
RD PRE
Q1 Q2
Q0
D0 D1 D2 D3
WR STOP
*Note1
t
BDL
D4 D5
Q3
9. MRS
*Note: 1. tBDL: 1 CLK; Last data in to burst stop delay.
Read or write burst stop command is valid at every burst length.
2. Number of valid output data after burst stop: 1, 2 for CAS latency = 2, 3 respectiviely.
3. Write burst is terminated. tBDL determinates the last data write.
4. DQM asserted to prevent corruption of locations D2 and D3.
5. Precharge can be issued here or earlier (satisfying tRAS min delay) with DQM.
6. PRE: All banks precharge, if necessary.
MRS can be issued only at all banks precharge state.
CLK
CMD PRE
*Note4
MRS ACT
tRP 2CLK
1)Mode Register Set
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 22/45
10. Clock Suspend Exit & Power Down Exit
11. Auto Refresh & Self Refresh
*Note: 1. Active power down : one or more banks active state.
2. Precharge power down: all banks precharge state.
3. The auto refresh is the same as CBR refresh of conventional DRAM.
No precharge commands are required after auto refresh command.
During tRFC from auto refresh command, any other command can not be accepted.
4. Before executing auto/self refresh command, all banks must be idle state.
5. MRS, Bank Active, Auto/Self Refresh, Power Down Mode Entry.
6. During self refresh entry, refresh interval and refresh operation are performed internally.
After self refresh entry, self refresh mode is kept while CKE is low.
During self refresh entry, all inputs expect CKE will be don’t cared, and outputs will be in Hi-Z state.
For the time interval of tRFC from self refresh exit command, any other command can not be accepted.
4K cycles of burst auto refresh is required immediately before self refresh entry and immediately after self refresh exit.
CLK
CKE
Internal
CLK
CMD RD
tSS
*Note1
CLK
CKE
Internal
CLK
CMD ACT
tSS
*Note2
NOP
1)Clock Suspend(=
A
ctive Powe
r
Down)Exit 2)Powe
r
Down (=P
r
echa
r
ge Powe
r
Down)
CLK
CMD PRE AR
CKE
CMD
t
RP
t
RFC
*Note5
*Note4
CLK
CMD PRE SR
CKE
CMD
t
RP
t
RFC
*Note4
1)Auto Refresh & Self Refresh
2)Self Refresh
*No
t
e3
*Note6
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 23/45
12. About Burst Type Control
Sequential Counting
At MRS A3 = “0”. See the BURST SEQUENCE TABLE. (BL = 4,8)
BL = 1, 2, 4, 8 and full page.
Basic
MODE
Interleave Counting At MRS A3 = “1”. See the BURST SEQUENCE TABLE. (BL = 4,8)
BL = 4, 8 At BL =1, 2 interleave Counting = Sequential Counting
Random
MODE
Random Column Access
tCCD = 1 CLK
Every cycle Read/Write Command with random column address can realize Random
Column Access.
That is similar to Extended Data Out (EDO) Operation of conventional DRAM.
13. About Burst Length Control
1 At MRS A210 = “000”
At auto precharge. tRAS should not be violated.
2 At MRS A210 = “001”
At auto precharge. tRAS should not be violated.
4 At MRS A210 = “010”
8 At MRS A210 = “011”
Basic
MODE
Full Page At MRS A210 = “111”
At the end of the burst length, burst is warp-around.
Special
MODE BRSW
At MRS A9 = “1”
Read burst = 1,2,4,8, full page write burst =1
At auto precharge of write, tRAS should not be violated.
Random
MODE Burst Stop tBDL = 1, Valid DQ after burst stop is 1, 2 for CAS latency 2, 3 respectively.
Using burst stop command, any burst length control is possible.
RAS Interrupt
(Interrupted by
Precharge)
Before the end of burst. Row precharge command of the same bank stops read /write burst
with auto precharge.
t
RDL = 1 with DQM , Valid DQ after burst stop is 1, 2 for CAS latency 2, 3 respectively.
During read/write burst with auto precharge, RAS interrupt can not be issued.
Interrupt
MODE
CAS Interrupt
Before the end of burst, new read/write stops read/write burst and starts new read/write
burst.
During read/write burst with auto precharge, CAS interrupt can not be issued.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 24/45
FUNCTION TRUTH TABLE (TABLE 1)
Current
State CS RAS CAS WE BA ADDR ACTION Note
H X X X X X NOP
L H H H X X NOP
L H H L X X ILLEGAL 2
IDLE L H L X BA CA, A10/AP ILLEGAL 2
L L H H BA RA Row (&Bank) Active ; Latch RA
L L H L BA A10/AP NOP 4
L L L H X X Auto Refresh or Self Refresh 5
L L L L OP code OP code Mode Register Access 5
H X X X X X NOP
L H H H X X NOP
L H H L X X ILLEGAL 2
Row L H L H BA CA, A10/AP Begin Read ; latch CA ; determine AP
Active L H L L BA CA, A10/AP Begin Write ; latch CA ; determine AP
L L H H BA RA ILLEGAL 2
L L H L BA A10/AP Precharge
L L L X X X ILLEGAL
H X X X X X NOP (Continue Burst to End Æ Row Active)
L H H H X X NOP (Continue Burst to End Æ Row Active)
L H H L X X Term burst Æ Row active
Read L H L H BA CA, A10/AP Term burst, New Read, Determine AP
L H L L BA CA, A10/AP Term burst, New Write, Determine AP 3
L L H H BA RA ILLEGAL 2
L L H L BA A10/AP Term burst, Precharge timing for Reads
L L L X X X ILLEGAL
H X X X X X NOP (Continue Burst to End Æ Row Active)
L H H H X X NOP (Continue Burst to End Æ Row Active)
L H H L X X Term burst Æ Row active
Write L H L H BA CA, A10/AP Term burst, New Read, Determine AP 3
L H L L BA CA, A10/AP Term burst, New Write, Determine AP 3
L L H H BA RA ILLEGAL 2
L L H L BA A10/AP Term burst, Precharge timing for Writes 3
L L L X X X ILLEGAL
H X X X X X NOP (Continue Burst to End Æ Row Active)
Read with L H H H X X NOP (Continue Burst to End Æ Row Active)
Auto L H H L X X ILLEGAL
Precharge L H L X BA CA, A10/AP ILLEGAL
L L H X BA RA, RA10 ILLEGAL 2
L L L X X X ILLEGAL
H X X X X X NOP (Continue Burst to End Æ Row Active)
Write with L H H H X X NOP (Continue Burst to End Æ Row Active)
Auto L H H L X X ILLEGAL
Precharge L H L X BA CA, A10/AP ILLEGAL
L L H X BA RA, RA10 ILLEGAL 2
L L L X X X ILLEGAL
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 25/45
Current
State CS RAS CAS WE BA ADDR ACTION Note
H X X X X X NOP Æ Idle after tRP
Read with L H H H X X NOP Æ Idle after tRP
Auto L H H L X X ILLEGAL 2
Precharge L H L X BA CA ILLEGAL 2
L L H H BA RA ILLEGAL 2
L L H L BA A10/AP NOP Æ Idle after tRP 4
L L L X X X ILLEGAL
H X X X X X NOP Æ Row Active after tRCD
L H H H X X NOP Æ Row Active after tRCD
Row L H H L X X ILLEGAL 2
Activating L H L X BA CA ILLEGAL 2
L L H H BA RA ILLEGAL 2
L L H L BA A10/AP ILLEGAL 2
L L L X X X ILLEGAL
H X X X X X NOP Æ Idle after tRFC
L H H X X X NOP Æ Idle after tRFC
Refreshing L H L X X X ILLEGAL
L L H X X X ILLEGAL
L L L X X X ILLEGAL
H X X X X X NOP Æ Idle after 2clocks
Mode L H H H X X NOP Æ Idle after 2clocks
Register L H H L X X ILLEGAL
Accessing L H L X X X ILLEGAL
L L X X X X ILLEGAL
Abbreviations: RA = Row Address BA = Bank Address
NOP = No Operation Command CA = Column Address AP = Auto Precharge
*Note: 1. All entries assume the CKE was active (High) during the precharge clock and the current clock cycle.
2. Illegal to bank in specified state; Function may be legal in the bank indicated by BA, depending on the state of the bank.
3. Must satisfy bus contention, bus turn around, and/or write recovery requirements.
4. NOP to bank precharge or in idle state. May precharge bank indicated by BA (and A10/AP).
5. Illegal if any bank is not idle.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 26/45
FUNCTION TRUTH TABLE (TABLE2)
Current
State
CKE
( n-1 )
CKE
n CS RAS CAS WE ADDR ACTION Note
H X X X X X X INVALID
L H H X X X X Exit Self Refresh Æ Idle after tRFC (ABI) 6
Self L H L H H H X Exit Self Refresh Æ Idle after tRFC (ABI) 6
Refresh L H L H H L X ILLEGAL
L H L H L X X ILLEGAL
L H L L X X X ILLEGAL
L L X X X X X NOP (Maintain Self Refresh)
H X X X X X X INVALID
All L H H X X X X Exit Self Refresh Æ ABI 7
Banks L H L H H H X Exit Self Refresh Æ ABI 7
Precharge L H L H H L X ILLEGAL
Power L H L H L X X ILLEGAL
Down L H L L X X X ILLEGAL
L L X X X X X NOP (Maintain Low Power Mode)
H H X X X X X Refer to Table1
H L H X X X X Enter Power Down 8
H L L H H H X Enter Power Down 8
H L L H H L X ILLEGAL
All H L L H L X X ILLEGAL
Banks H L L L H H RA Row (& Bank) Active
Idle H L L L H H X NOP
H L L L L H X Enter Self Refresh 8
H L L L L L OP Code Mode Register Access
L L X X X X X NOP
Any State H H X X X X X Refer to Operations in Table 1
other than H L X X X X X Begin Clock Suspend next cycle 9
Listed L H X X X X X Exit Clock Suspend next cycle 9
above L L X X X X X Maintain Clock Suspend
Abbreviations: ABI = All Banks Idle, RA = Row Address
*Note: 6.CKE low to high transition is asynchronous.
7.CKE low to high transition is asynchronous if restart internal clock.
A minimum setup time 1CLK + tSS must be satisfy before any command other than exit.
8.Power down and self refresh can be entered only from the all banks idle state.
9.Must be a legal command.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 27/45
Single Bit Read-Write-Read Cycle (Same Page) @ CAS Latency = 3, Burst Length = 1
:Don't Care
0 1 2 3 4 5 6 7 8 9 10111213141516171819
CLOCK
CKE
CS
RAS
CAS
ADDR
WE
DQ
DQM
A10/AP
t
CH
t
CL
t
CC
Row Active
BA0, BA1
*Note1
HIGH
t
RCD
t
SS
t
SS
t
SH
t
SH
t
SS
t
SH
t
SS
t
SS
t
SS
t
SH
Ra Ca Cb Cc Rb
BS
BS
BS
BS
BSBS
Ra
Qa Db Qc
Rb
Read Write Read
Precharge
Row Active
t
RC
t
RAS
t
RP
t
CCD
*Note2 *Note2,3 *Note4 *Note2*Note2,3
*Note 2 *Note 2
*Note2,3
t
SH
t
SLZ
t
SAC
t
OH
t
SH
t
SH
t
SS
*Note4
*Note 2
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 28/45
Note: 1. All input expect CKE & DQM can be don’t care when CS is high at the CLK high going edge.
2. Bank active @ read/write are controlled by BA0~BA1.
BA0 BA1 Active & Read/Write
0 0 Bank A
0 1 Bank B
1 0 Bank C
1 1 Bank D
3. Enable and disable auto precharge function are controlled by A10/AP in read/write command
A10/AP BA0 BA1 Operating
0 0 Disable auto precharge, leave A bank active at end of burst.
0 1 Disable auto precharge, leave B bank active at end of burst.
1 0 Disable auto precharge, leave C bank active at end of burst.
0
1 1 Disable auto precharge, leave D bank active at end of burst.
0 0 Enable auto precharge, precharge bank A at end of burst.
0 1 Enable auto precharge, precharge bank B at end of burst.
1 0 Enable auto precharge, precharge bank C at end of burst.
1
1 1 Enable auto precharge, precharge bank D at end of burst.
4. A10/AP and BA0~BA1 control bank precharge when precharge is asserted.
A10/AP BA0 BA1 Precharge
0 0 0 Bank A
0 0 1 Bank B
0 1 0 Bank C
0 1 1 Bank D
1 X X All Banks
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 29/45
Power Up Sequence
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 30/45
Read & Write Cycle at Same Bank @ Burst Length = 4
*Note: 1. Minimum row cycle times is required to complete internal DRAM operation.
2. Row precharge can interrupt burst on any cycle. [CAS Latency-1] number of valid output data is available after Row
precharge. Last valid output will be Hi-Z (tSHZ) after the clock.
3. Output will be Hi-Z after the end of burst. (1, 2, 4, 8 & Full page bit burst)
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 31/45
Page Read & Write Cycle at Same Bank @ Burst Length = 4
Note: 1. To Write data before burst read ends. DQM should be asserted three cycle prior to write command to avoid bus contention.
2. Row precharge will interrupt writing. Last data input, tRDL before row precharge, will be written.
3. DQM should mask invalid input data on precharge command cycle when asserting precharge before end of burst. Input
data after Row precharge cycle will be masked internally.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 32/45
Page Read Cycle at Different Bank @ Burst Length = 4
Note: 1. CS can be don’t cared when RAS , CAS and WE are high at the clock high going edge.
2. To interrupt a burst read by row precharge, both the read and the precharge banks must be the same.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 33/45
Page Write Cycle at Different Bank @ Burst Length = 4
*Note: 1. To interrupt burst write by Row precharge, DQM should be asserted to mask invalid input data.
2. To interrupt burst write by Row precharge, both the write and the precharge banks must be the same.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 34/45
Read & Write Cycle at Different Bank @ Burst Length = 4
*Note: 1. tCDL should be met to complete write.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 35/45
Read & Write cycle with Auto Precharge @ Burst Length = 4
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 36/45
Clock Suspension & DQM Operation Cycle @ CAS Latency = 2, Burst Length = 4
*Note: 1. DQM is needed to prevent bus contention
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 37/45
Read interrupted by Precharge Command & Read Burst Stop Cycle @ Burst Length = Full page
*Note: 1. About the valid DQs after burst stop, it is same as the case of RAS interrupt.
Both cases are illustrated above timing diagram. See the label 1,2 on them.
But at burst write, Burst stop and RAS interrupt should be compared carefully.
Refer the timing diagram of “Full page write burst stop cycles”.
2. Burst stop is valid at every burst length.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 38/45
Write interrupted by Precharge Command & Write Burst Stop Cycle @ Burst Length = Full page
*Note: 1. Data-in at the cycle of interrupted by precharge can not be written into the corresponding memory cell. It is defined by
AC parameter of tRDL.
DQM at write interrupted by precharge command is needed to prevent invalid write.
DQM should mask invalid input data on precharge command cycle when asserting precharge before end of burst. Input
data after Row precharge cycle will be masked internally.
2. Burst stop is valid at every burst length.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 39/45
Active/Precharge Power Down Mode @ CAS Latency = 2, Burst Length = 4
*Note: 1. All banks should be in idle state prior to entering precharge power down mode.
2. CKE should be set high at least 1CLK + tSS prior to Row active command.
3. Can not violate minimum refresh specification.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 40/45
Self Refresh Entry & Exit Cycle
*Note:
TO ENTER SELF REFRESH MODE
1. CS , RAS & CAS with CKE should be low at the same clock cycle.
2. After 1 clock cycle, all the inputs including the system clock can be don’t care except for CKE.
3. The device remains in self refresh mode as long as CKE stays “Low”.
cf.) Once the device enters self refresh mode, minimum tRAS is required before exit from self refresh.
TO EXIT SELF REFRESH MODE
4. System clock restart and be stable before returning CKE high.
5. CS starts from high.
6. Minimum tRFC is required after CKE going high to complete self refresh exit.
7. 4K cycles of burst auto refresh is required immediately before self refresh entry and immediately after self refresh exit.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 41/45
Mode Register Set Cycle Auto Refresh Cycle
CLOCK
CKE
CS
RAS
CAS
ADDR
WE
DQ
DQM
:Don't Care
HIGH
0 12 34 5 6 01 23 45 67 8 910
HIGH
Key Ra
HI-Z HI-Z
*Note2
*Note1
*Note3
tRFC
MRS New
Command
Auto Refresh New Command
All banks precharge should be completed before Mode Register Set cycle and auto refresh cycle.
MODE REGISTER SET CYCLE
*Note: 1. CS , RAS , CAS , & WE activation at the same clock cycle with address key will set internal mode register.
2. Minimum 2 clock cycles should be met before new RAS activation.
3. Please refer to Mode Register Set table.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 42/45
PACKING DIMENSIONS
54-LEAD TSOP(II) SDRAM (400mil)
Symbol Dimension in mm Dimension in inch
Min Norm Max Min Norm Max
A
1.20
0.047
A1 0.05 0.10 0.15 0.002 0.004 0.006
A2 0.95 1.00 1.05 0.037 0.039 0.041
b 0.30
0.45 0.012
0.018
b1 0.30 0.35 0.40 0.012 0.014 0.016
c 0.12
0.21 0.005
0.008
c1 0.10 0.127 0.16 0.004 0.005 0.006
D 22.22 BSC 0.875 BSC
ZD 0.71 REF 0.028 REF
E 11.76 BSC 0.463 BSC
E1 10.16 BSC 0.400 BSC
L 0.40 0.50 0.60 0.016 0.020 0.024
L1 0.80 REF 0.031 REF
e 0.80 BSC 0.031 BSC
R1 0.12
0.005
R2 0.12
0.25 0.005
0.010
θ °0 °8 °0 °8
θ
1 °0 °0
θ
2 °10 °15 °20 °10 °15 °20
θ
3 °10 °15 °20 °10 °15 °20
y
0.100 0.004
SEE DETAIL "A"
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 43/45
PACKING DIMENSIONS
54-BALL SDRAM ( 8x8 mm )
Symbol Dimension in mm Dimension in inch
Min Norm Max Min Norm Max
A
1.00
0.039
A1 0.20 0.25 0.30 0.008 0.010 0.012
A2 0.61 0.66 0.71 0.024 0.026 0.028
Φb 0.30 0.35 0.40 0.012 0.014 0.016
D 7.90 8.00 8.10 0.311 0.315 0.319
E 7.90 8.00 8.10 0.311 0.315 0.319
D1
6.40
0.252
E1
6.40
0.252
e
0.80
0.031
Controlling dimension : Millimeter.
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 44/45
Revision History
Revision Date Description
1.0 2002.10.31 Original
1.1 2003.03.25 Modify die from 0.165mm to 0.15mm
1.2 2003.09.02
Delete speed distribution -5 to prevent confusion of
customers
1.3 2004.08.23 Correct typing error
1.4 2005.03.17
1.Add Pb-free to ordering information
2.Modify P8 from bank precharge state to ldle state
1.5 2005.04.22 Modify refresh spec
1.6 2005.06.07
1.Modify tREF spec
2.Modify tRFC spec
1.7 2005.09.02 Add revision history
1.8 2006.09.08 Add -5T to ordering information
1.9 2006.10.11
1.Modify AC parameter (tCH, tCL, tRP, tRAS, tRC)
2.Modify tSAC, tOH timing
2.0 2006.10.24 Modify tRFC , tSHZ timing
2.1 2007.07.18 Add BGA package
2.2 2009.02.23
1.Rename A13,A12 to BA0,BA1
2.Modify the specification of tOH for -6 and -7
3.Modify the test condition of lIL and ICC3N
4.Modify the description about self refresh operation
2.3 2009.03.05
Chang back to the specification of tOH of the previous
version
2.4 2009.10.02
1. Add the description about A9 bit of MRS
2. Delete the unnecessary description about self refresh
ESMT
M12L128168A
Elite Semiconductor Memory Technology Inc. Publication Date: Oct. 2009
Revision: 2.4 45/45
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