ISSI IS42S16800D-7BL

IS42S81600D
IS42S16800D
16Meg x 8, 8Meg x16
128-MBIT SYNCHRONOUS DRAM
JULY 2008
• Clock frequency: 166, 143, 133 MHz
OVERVIEW
ISSI's 128Mb Synchronous DRAM achieves high-speed
• Fully synchronous; all signals referenced to a
positive clock edge
data transfer using pipeline architecture. All inputs and
outputs signals refer to the rising edge of the clock
input.The 128Mb SDRAM is organized as follows.
FEATURES
• Internal bank for hiding row access/precharge
• Power supply
IS42S81600D
VDDQ
VDD
3.3V 3.3V
IS42S16800D
3.3V 3.3V
IS42S81600D
IS42S16800D
4M x8x4 Banks
2M x16x4 Banks
54-pin TSOPII
54-pin TSOPII
• LVTTL interface
54-ball BGA
• Programmable burst length
– (1, 2, 4, 8, full page)
• Programmable burst sequence:
Sequential/Interleave
• Auto Refresh (CBR)
• Self Refresh with programmable refresh periods
KEY TIMING PARAMETERS
• 4096 refresh cycles every 64 ms
Parameter
-6
-7
-75E
Unit
• Random column address every clock cycle
Clk Cycle Time
CAS Latency = 3
CAS Latency = 2
6
8
7
10
—
7.5
ns
ns
Clk Frequency
CAS Latency = 3
CAS Latency = 2
166
125
143
100
—
133
Mhz
Mhz
Access Time from Clock
CAS Latency = 3
CAS Latency = 2
5.4
6.5
5.4
6.5
—
6.5
ns
ns
• Programmable CAS latency (2, 3 clocks)
• Burst read/write and burst read/single write
operations capability
• Burst termination by burst stop and precharge
command
• Industrial Temperature Availability
• Lead-free Availability
Copyright © 2006 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. — www.issi.com
Rev. E
07/28/08
1
IS42S81600D,
IS42S16800D
DEVICE OVERVIEW
The 128Mb SDRAM is a high speed CMOS, dynamic
random-access memory designed to operate in 3.3V VDD
and 3.3V VDDQ memory systems containing 134,217,728
bits. Internally configured as a quad-bank DRAM with a
synchronous interface. Each 33,554,432-bit bank is organized as 4,096 rows by 512 columns by 16 bits or 4,096 rows
by 1,024 columns by 8 bits.
The 128Mb SDRAM includes an AUTO REFRESH MODE,
and a power-saving, power-down mode. All signals are
registered on the positive edge of the clock signal, CLK. All
inputs and outputs are LVTTL compatible.
The 128Mb SDRAM has the ability to synchronously burst
data at a high data rate with automatic column-address
generation, the ability to interleave between internal banks
to hide precharge time and the capability to randomly
change column addresses on each clock cycle during
burst access.
A self-timed row precharge initiated at the end of the burst
sequence is available with the AUTO PRECHARGE function enabled. Precharge one bank while accessing one of the
other three banks will hide the precharge cycles and provide
seamless, high-speed, random-access operation.
SDRAM read and write accesses are burst oriented starting at
a selected location and continuing for a programmed number of locations in a programmed sequence. The registration of an ACTIVE command begins accesses, followed by
a READ or WRITE command. The ACTIVE command in
conjunction with address bits registered are used to select
the bank and row to be accessed (BA0, BA1 select the
bank; A0-A11 select the row). The READ or WRITE
commands in conjunction with address bits registered are
used to select the starting column location for the burst
access.
Programmable READ or WRITE burst lengths consist of 1,
2, 4 and 8 locations or full page, with a burst terminate
option.
FUNCTIONAL BLOCK DIAGRAM (FOR 2MX16X4 BANKS ONLY)
DQML
DQMH
DATA IN
BUFFER
COMMAND
DECODER
&
CLOCK
GENERATOR
16
MODE
REGISTER
12
2
SELF
DQ 0-15
VDD/VDDQ
DATA OUT
BUFFER
REFRESH
A10
CONTROLLER
A11
A9
A8
A7
A6
A5
A4
A3
A2
A1
A0
BA0
BA1
16
REFRESH
CONTROLLER
Vss/VssQ
16
16
12
MULTIPLEXER
REFRESH
COUNTER
ROW
ADDRESS
LATCH
12
12
COLUMN
ADDRESS LATCH
ROW
ADDRESS
BUFFER
ROW DECODER
CLK
CKE
CS
RAS
CAS
WE
4096
4096
4096
4096
MEMORY CELL
ARRAY
BANK 0
SENSE AMP I/O GATE
512
(x 16)
BANK CONTROL LOGIC
9
BURST COUNTER
COLUMN
ADDRESS BUFFER
2
COLUMN DECODER
9
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Rev. E
07/28/08
IS42S81600D,
IS42S16800D
PIN CONFIGURATIONS
54 pin TSOP - Type II for x8
VDD
1
54
VSS
DQ0
2
53
DQ7
VDDQ
3
52
VSSQ
NC
4
51
NC
DQ1
5
50
DQ6
VSSQ
6
49
VDDQ
NC
7
48
NC
DQ2
8
47
DQ5
VDDQ
9
46
VSSQ
NC
10
45
NC
DQ3
11
44
DQ4
VSSQ
12
43
VDDQ
NC
13
42
NC
VDD
14
41
VSS
NC
15
40
NC
WE
16
39
DQM
CAS
17
38
CLK
RAS
18
37
CKE
CS
19
36
NC
BA0
20
35
A11
BA1
21
34
A9
A10
22
33
A8
A0
23
32
A7
A1
24
31
A6
A2
25
30
A5
A3
26
29
A4
VDD
27
28
VSS
PIN DESCRIPTIONS
A0-A11
Row Address Input
WE
Write Enable
A0-A9
Column Address Input
DQM
Data Input/Output Mask
BA0, BA1
Bank Select Address
VDD
Power
DQ0 to DQ7
Data I/O
Vss
Ground
CLK
System Clock Input
VDDQ
Power Supply for I/O Pin
CKE
Clock Enable
VssQ
Ground for I/O Pin
CS
Chip Select
NC
No Connection
RAS
Row Address Strobe Command
CAS
Column Address Strobe Command
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Rev. E
07/28/08
3
IS42S81600D,
IS42S16800D
PIN CONFIGURATIONS
54 pin TSOP - Type II for x16
VDD
1
54
VSS
DQ0
2
53
DQ15
VDDQ
3
52
VSSQ
DQ1
4
51
DQ14
DQ2
5
50
DQ13
VSSQ
6
49
VDDQ
DQ3
7
48
DQ12
DQ4
8
47
DQ11
VDDQ
9
46
VSSQ
DQ5
10
45
DQ10
DQ6
11
44
DQ9
VSSQ
12
43
VDDQ
DQ7
13
42
DQ8
VDD
14
41
VSS
LDQM
15
40
NC
WE
16
39
UDQM
CAS
17
38
CLK
RAS
18
37
CKE
CS
19
36
NC
BA0
20
35
A11
BA1
21
34
A9
A10
22
33
A8
A0
23
32
A7
A1
24
31
A6
A2
25
30
A5
A3
26
29
A4
VDD
27
28
VSS
PIN DESCRIPTIONS
A0-A11
Row Address Input
WE
Write Enable
A0-A8
Column Address Input
DQML
x16 Lower Byte, Input/Output Mask
BA0, BA1
Bank Select Address
DQMH
x16 Upper Byte, Input/Output Mask
DQ0 to DQ15
Data I/O
VDD
Power
CLK
System Clock Input
Vss
Ground
CKE
Clock Enable
VDDQ
Power Supply for I/O Pin
CS
Chip Select
VssQ
Ground for I/O Pin
RAS
Row Address Strobe Command
NC
No Connection
CAS
Column Address Strobe Command
4
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
IS42S81600D,
IS42S16800D
PIN CONFIGURATION
54-ball fBGA for x16 (Top View) (8.00 mm x 13.00 mm Body, 0.8 mm Ball Pitch)
PACKAGE CODE: B
1 2 3 4 5 6 7 8 9
A
B
C
D
E
F
G
H
J
VSS DQ15 VSSQ
VDDQ DQ0 VDD
DQ14 DQ13 VDDQ
VSSQ DQ2 DQ1
DQ12 DQ11 VSSQ
VDDQ DQ4 DQ3
DQ10 DQ9 VDDQ
VSSQ DQ6 DQ5
DQ8
NC
VSS
VDD DQML DQ7
DQMH CLK
CKE
CAS
RAS
WE
NC
A11
A9
BA0
BA1
CS
A8
A7
A6
A0
A1
A10
VSS
A5
A4
A3
A2
VDD
PIN DESCRIPTIONS
A0-A11
Row Address Input
WE
Write Enable
A0-A8
Column Address Input
DQML
x16 Lower Byte Input/Output Mask
BA0, BA1
Bank Select Address
DQMH
x16 Upper Byte Input/Output Mask
DQ0 to DQ15
Data I/O
VDD
Power
CLK
System Clock Input
Vss
Ground
CKE
Clock Enable
VDDQ
Power Supply for I/O Pin
CS
Chip Select
VssQ
Ground for I/O Pin
RAS
Row Address Strobe Command
NC
No Connection
CAS
Column Address Strobe Command
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Rev. E
07/28/08
5
IS42S81600D,
IS42S16800D
PIN FUNCTIONS
Symbol
Type
A0-A11
Input Pin
Address Inputs: A0-A11 are sampled during the ACTIVE
command (row-address A0-A11) and READ/WRITE command (column address A0-A9
(x8), or A0-A8 (x16); with A10 defining auto precharge) to select one location out of the
memory array in the respective bank. A10 is sampled during a PRECHARGE command
to determine if all banks are to be precharged (A10 HIGH) or bank selected by
BA0, BA1 (LOW). The address inputs also provide the op-code during a LOAD MODE
REGISTER command.
BA0, BA1
Input Pin
Bank Select Address: BA0 and BA1 defines which bank the ACTIVE, READ, WRITE or
PRECHARGE command is being applied.
CAS
Input Pin
CAS, in conjunction with the RAS and WE, forms the device command. See the
"Command Truth Table" for details on device commands.
CKE
Input Pin
The CKE input determines whether the CLK input is enabled. The next rising edge of the
CLK signal will be valid when is CKE HIGH and invalid when LOW. When CKE is LOW,
the device will be in either power-down mode, clock suspend mode, or self refresh
mode. CKE is an asynchronous input.
CLK
Input Pin
CLK is the master clock input for this device. Except for CKE, all inputs to this device
are acquired in synchronization with the rising edge of this pin.
CS
Input Pin
The CS input determines whether command input is enabled within the device.
Command input is enabled when CS is LOW, and disabled with CS is HIGH. The device
remains in the previous state when CS is HIGH.
DQML,
DQMH
Input Pin
DQML and DQMH control the lower and upper bytes of the I/O buffers. In read
mode,DQML and DQMH control the output buffer. WhenDQML orDQMH is LOW, the
corresponding buffer byte is enabled, and when HIGH, disabled. The outputs go to the
HIGH impedance state whenDQML/DQMH is HIGH. This function corresponds to OE
in conventional DRAMs. In write mode,DQML and DQMH control the input buffer. When
DQML or DQMH is LOW, the corresponding buffer byte is enabled, and data can be
written to the device. WhenDQML or DQMH is HIGH, input data is masked and cannot
be written to the device. For IS42S16800D only.
DQM
Input Pin
For IS42S81600D only.
DQ0-DQ7 or
DQ0-DQ15
Input/Output
Data on the Data Bus is latched on DQ pins during Write commands, and buffered for
output after Read commands.
RAS
Input Pin
RAS, in conjunction with CAS and WE, forms the device command. See the "Command
Truth Table" item for details on device commands.
WE
Input Pin
WE, in conjunction with RAS and CAS, forms the device command. See the "Command
Truth Table" item for details on device commands.
6
Function (In Detail)
VDDQ
Power Supply Pin
VDDQ is the output buffer power supply.
VDD
Power Supply Pin
VDD is the device internal power supply.
VSSQ
Power Supply Pin
VSSQ is the output buffer ground.
VSS
Power Supply Pin
VSS is the device internal ground.
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Rev. E
07/28/08
IS42S81600D,
IS42S16800D
GENERAL DESCRIPTION
READ
The READ command selects the bank from BA0, BA1
inputs and starts a burst read access to an active row.
Inputs A0-A9 (x8); A0-A8 (x16) provides the starting column
location. When A10 is HIGH, this command functions as an
AUTO PRECHARGE command. When the auto precharge
is selected, the row being accessed will be precharged at
the end of the READ burst. The row will remain open for
subsequent accesses when AUTO PRECHARGE is not
selected. DQ’s read data is subject to the logic level on the
DQM inputs two clocks earlier. When a given DQM signal
was registered HIGH, the corresponding DQ’s will be HighZ two clocks later. DQ’s will provide valid data when the
DQM signal was registered LOW.
WRITE
A burst write access to an active row is initiated with the
WRITE command. BA0, BA1 inputs selects the bank, and
the starting column location is provided by inputs A0-A9
(x8); A0-A8 (x16). Whether or not AUTO-PRECHARGE is
used is determined by A10.
The row being accessed will be precharged at the end of the
WRITE burst, if AUTO PRECHARGE is selected. If AUTO
PRECHARGE is not selected, the row will remain open for
subsequent accesses.
A memory array is written with corresponding input data on
DQ’s and DQM input logic level appearing at the same time.
Data will be written to memory when DQM signal is LOW.
When DQM is 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. BA0,
BA1 can be used to select which bank is precharged or they
are treated as “Don’t Care”. A10 determined whether one or
all banks are precharged. After executing this command,
the next command for the selected bank(s) is executed after
passage of the period tRP, which is the period required for
bank precharging. 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.
AUTO PRECHARGE
The AUTO PRECHARGE function ensures that the precharge
is initiated at the earliest valid stage within a burst. This
function allows for individual-bank precharge without requiring an explicit command. A10 to enable the AUTO
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Rev. E
07/28/08
PRECHARGE function in conjunction with a specific READ
or WRITE command. For each individual READ or WRITE
command, auto precharge is either enabled or disabled.
AUTO PRECHARGE does not apply except in full-page
burst mode. Upon completion of the READ or WRITE burst,
a precharge of the bank/row that is addressed is automatically performed.
AUTO REFRESH COMMAND
This command executes the AUTO REFRESH operation.
The row address and bank to be refreshed are automatically
generated during this operation. The stipulated period (tRC) is
required for a single refresh operation, and no other commands can be executed during this period. This command is
executed at least 4096 times for every 64ms. During an
AUTO REFRESH command, address bits are “Don’t Care”.
This command corresponds to CBR Auto-refresh.
BURST TERMINATE
The BURST TERMINATE command forcibly terminates the
burst read and write operations by truncating either fixedlength or full-page bursts and the most recently registered
READ or WRITE command prior to the BURST TERMINATE.
COMMAND INHIBIT
COMMAND INHIBIT prevents new commands from being
executed. Operations in progress are not affected, apart
from whether the CLK signal is enabled
NO OPERATION
When CS is low, the NOP command prevents unwanted
commands from being registered during idle or wait states.
LOAD MODE REGISTER
During the LOAD MODE REGISTER command the mode
register is loaded from A0-A11. This command can only be
issued when all banks are idle.
ACTIVE COMMAND
When the ACTIVE COMMAND is activated, BA0, BA1
inputs selects a bank to be accessed, and the address
inputs on A0-A11 selects the row. Until a PRECHARGE
command is issued to the bank, the row remains open for
accesses.
7
IS42S81600D,
IS42S16800D
COMMAND TRUTH TABLE
CKE
Function
n–1
Device deselect (DESL)
H
No operation (NOP)
H
Burst stop (BST)
H
Read
H
Read with auto precharge
H
Write
H
Write with auto precharge
H
Bank activate (ACT)
H
Precharge select bank (PRE) H
Precharge all banks (PALL) H
CBR Auto-Refresh (REF)
H
Self-Refresh (SELF)
H
Mode register set (MRS)
H
n
×
×
×
×
×
×
×
×
×
×
H
L
×
CS
H
L
L
L
L
L
L
L
L
L
L
L
L
RAS
×
H
H
H
H
H
H
L
L
L
L
L
L
CAS
×
H
H
L
L
L
L
H
H
H
L
L
L
WE
×
H
L
H
H
L
L
H
L
L
H
H
L
BA1
×
×
×
V
V
V
V
V
V
×
×
×
L
BA0
×
×
×
V
V
V
V
V
V
×
×
×
L
A10
×
×
×
L
H
L
H
V
L
H
×
×
L
A11
A9 - A0
×
×
×
V
V
V
V
V
×
×
×
×
V
Note: H=VIH, L=VIL x= VIH or VIL, V = Valid Data.
DQM TRUTH TABLE
Function
Data write / output enable
Data mask / output disable
Upper byte write enable / output enable
Lower byte write enable / output enable
Upper byte write inhibit / output disable
Lower byte write inhibit / output disable
CKE
n-1
H
H
H
H
H
H
n
×
×
×
×
×
×
DQM
U
L
H
L
×
H
×
L
L
H
×
L
×
H
Note: H=VIH, L=VIL x= VIH or VIL, V = Valid Data.
8
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Rev. E
07/28/08
IS42S81600D,
IS42S16800D
CKE TRUTH TABLE
CKE
Current State /Function
Activating Clock suspend mode entry
Any Clock suspend mode
Clock suspend mode exit
Auto refresh command Idle (REF)
Self refresh entry Idle (SELF)
Power down entry Idle
Self refresh exit
Power down exit
n–1
H
L
L
H
H
H
L
L
L
n
L
L
H
H
L
L
H
H
H
CS
×
×
×
L
L
×
L
H
×
RAS
×
×
×
L
L
×
H
×
×
CAS
×
×
×
L
L
×
H
×
×
WE
×
×
×
H
H
×
H
×
×
Address
×
×
×
×
×
×
×
×
×
Note: H=VIH, L=VIL x= VIH or VIL, V = Valid Data.
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Rev. E
07/28/08
9
IS42S81600D,
IS42S16800D
FUNCTIONAL TRUTH TABLE
Current State
CS
RAS CAS
WE
Address
Command
Action
Idle
H
X
X
X
X
DESL
Nop or Power Down(2)
L
H
H
H
X
NOP
Nop or Power Down(2)
L
H
H
L
X
BST
Nop or Power Down
L
H
L
H
BA, CA, A10
READ/READA
ILLEGAL (3)
L
H
L
L
A, CA, A10
WRIT/ WRITA
ILLEGAL(3)
L
L
H
H
BA, RA
ACT
Row activating
Row Active
Read
Write
L
L
H
L
BA, A10
PRE/PALL
Nop
L
L
L
H
X
REF/SELF
Auto refresh or Self-refresh(4)
L
L
L
L
OC, BA1=L
MRS
Mode register set
H
X
X
X
X
DESL
Nop
L
H
H
H
X
NOP
Nop
L
H
H
L
X
BST
Nop
L
H
L
H
BA, CA, A10
READ/READA
Begin read
(5)
L
H
L
L
BA, CA, A10
WRIT/ WRITA
Begin write
(5)
L
L
H
H
BA, RA
ACT
ILLEGAL (3)
L
L
H
L
BA, A10
PRE/PALL
Precharge
Precharge all banks(6)
L
L
L
H
X
REF/SELF
ILLEGAL
L
L
L
L
OC, BA
MRS
ILLEGAL
H
X
X
X
X
DESL
Continue burst to end to
Row active
L
H
H
H
X
NOP
Continue burst to end Row
Row active
L
H
H
L
X
BST
Burst stop, Row active
L
H
L
H
BA, CA, A10
READ/READA
Terminate burst,
begin new read (7)
L
H
L
L
BA, CA, A10
WRIT/WRITA
Terminate burst,
begin write (7,8)
L
L
H
H
BA, RA
ACT
ILLEGAL (3)
L
L
H
L
BA, A10
PRE/PALL
Terminate burst
Precharging
L
L
L
H
X
REF/SELF
ILLEGAL
L
L
L
L
OC, BA
MRS
ILLEGAL
H
X
X
X
X
DESL
Continue burst to end
Write recovering
L
H
H
H
X
NOP
Continue burst to end
Write recovering
L
H
H
L
X
BST
Burst stop, Row active
L
H
L
H
BA, CA, A10
READ/READA
Terminate burst, start read :
Determine AP (7,8)
L
H
L
L
BA, CA, A10
WRIT/WRITA
Terminate burst, new write :
Determine AP (7)
L
L
H
H
BA, RA
RA ACT
ILLEGAL (3)
L
L
H
L
BA, A10
PRE/PALL
Terminate burst Precharging
L
L
L
H
X
REF/SELF
ILLEGAL
L
L
L
L
OC, BA
MRS
ILLEGAL
(9)
Note: H=VIH, L=VIL x= VIH or VIL, V = Valid Data, BA= Bank Address, CA+Column Address, RA=Row Address, OC= Op-Code
10
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Rev. E
07/28/08
IS42S81600D,
IS42S16800D
FUNCTIONAL TRUTH TABLE Continued:
Current State
CS
RAS CAS
WE
Address
Command
Action
Read with auto
Precharging
H
×
×
×
×
DESL
Continue burst to end, Precharge
L
H
H
H
x
NOP
Continue burst to end, Precharge
L
H
H
L
×
BST
ILLEGAL
L
H
L
H
BA, CA, A10
READ/READA
ILLEGAL (11)
L
H
L
L
BA, CA, A10
WRIT/ WRITA
ILLEGAL (11)
L
L
H
H
BA, RA
ACT
ILLEGAL (3)
L
L
H
L
BA, A10
PRE/PALL
ILLEGAL (11)
ILLEGAL
Write with Auto
Precharge
Precharging
Row Activating
L
L
L
H
×
REF/SELF
L
L
L
L
OC, BA
MRS
ILLEGAL
H
×
×
×
×
DESL
Continue burst to end, Write
recovering with auto precharge
L
H
H
H
×
NOP
Continue burst to end, Write
recovering with auto precharge
L
H
H
L
×
BST
ILLEGAL
L
H
L
H
BA, CA, A10
READ/READA
ILLEGAL(11)
L
H
L
L
BA, CA, A10
WRIT/ WRITA
ILLEGAL (11)
L
L
H
H
BA, RA
ACT
ILLEGAL (3,11)
L
L
H
L
BA, A10
PRE/PALL
ILLEGAL (3,11)
L
L
L
H
×
REF/SELF
ILLEGAL
L
L
L
L
OC, BA
MRS
ILLEGAL
H
×
×
×
×
DESL
Nop, Enter idle after tRP
L
H
H
H
×
NOP
Nop, Enter idle after tRP
L
H
H
L
×
BST
Nop, Enter idle after tRP
L
H
L
H
BA, CA, A10
READ/READA
ILLEGAL (3)
L
H
L
L
BA, CA, A10
WRIT/WRITA
ILLEGAL (3)
L
L
H
H
BA, RA
ACT
ILLEGAL(3)
L
L
H
L
BA, A10
PRE/PALL
Nop Enter idle after tRP
L
L
L
H
×
REF/SELF
ILLEGAL
L
L
L
L
OC, BA
MRS
ILLEGAL
H
×
×
×
×
DESL
Nop, Enter bank active after tRCD
L
H
H
H
×
NOP
Nop, Enter bank active after tRCD
L
H
H
L
×
BST
Nop, Enter bank active after tRCD
L
H
L
H
BA, CA, A10
READ/READA
ILLEGAL (3)
L
H
L
L
BA, CA, A10
WRIT/WRITA
ILLEGAL (3)
L
L
H
H
BA, RA
ACT
ILLEGAL (3,9)
L
L
H
L
BA, A10
PRE/PALL
ILLEGAL (3)
L
L
L
H
×
REF/SELF
ILLEGAL
L
L
L
L
OC, BA
MRS
ILLEGAL
Note: H=VIH, L=VIL x= VIH or VIL, V = Valid Data, BA= Bank Address, CA+Column Address, RA=Row Address, OC= Op-Code
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
11
IS42S81600D,
IS42S16800D
FUNCTIONAL TRUTH TABLE Continued:
Current State
Write Recovering
CS
RAS CAS
WE
Address
Command
Action
Nop, Enter row active after tDPL
H
×
×
×
×
DESL
L
H
H
H
×
NOP
Nop, Enter row active after tDPL
L
H
H
L
×
BST
Nop, Enter row active after tDPL
L
H
L
H
BA, CA, A10
READ/READA
Begin read (8)
L
H
L
L
BA, CA, A10
WRIT/ WRITA
Begin new write
L
L
H
H
BA, RA
ACT
ILLEGAL (3)
L
L
H
L
BA, A10
PRE/PALL
ILLEGAL (3)
L
L
L
H
×
REF/SELF
ILLEGAL
L
L
L
L
OC, BA
MRS
ILLEGAL
Write Recovering
H
×
×
×
×
DESL
Nop, Enter precharge after tDPL
with Auto
L
H
H
H
×
NOP
Nop, Enter precharge after tDPL
Precharge
L
H
H
L
×
BST
Nop, Enter row active after tDPL
L
H
L
H
BA, CA, A10
READ/READA
ILLEGAL(3,8,11)
L
H
L
L
BA, CA, A10
WRIT/WRITA
ILLEGAL (3,11)
L
L
H
H
BA, RA
ACT
ILLEGAL (3,11)
L
L
H
L
BA, A10
PRE/PALL
ILLEGAL (3,11)
L
L
L
H
×
REF/SELF
ILLEGAL
L
L
L
L
OC, BA
MRS
ILLEGAL
H
×
×
×
×
DESL
Nop, Enter idle after tRC
L
H
H
×
×
NOP/BST
Nop, Enter idle after tRC
L
H
L
H
BA, CA, A10
READ/READA
ILLEGAL
L
H
L
L
BA, CA, A10
WRIT/WRITA
ILLEGAL
L
L
H
H
BA, RA
ACT
ILLEGAL
L
L
H
L
BA, A10
PRE/PALL
ILLEGAL
L
L
L
H
×
REF/SELF
ILLEGAL
Refresh
L
L
L
L
OC, BA
MRS
ILLEGAL
Mode Register
H
×
×
×
×
DESL
Nop, Enter idle after 2 clocks
Accessing
L
H
H
H
×
NOP
Nop, Enter idle after 2 clocks
L
H
H
L
×
BST
ILLEGAL
L
H
L
×
BA, CA, A10
READ/WRITE
ILLEGAL
L
L
×
×
BA, RA
ACT/PRE/PALL
REF/MRS
ILLEGAL
Note: H=VIH, L=VIL x= VIH or VIL, V = Valid Data, BA= Bank Address, CA+Column Address, RA=Row Address, OC= Op-Code
Notes:
1. All entries assume that CKE is active (CKEn-1=CKEn=H).
2. If both banks are idle, and CKE is inactive (Low), the device will enter Power Down mode. All input buffers except CKE will
be disabled.
3. Illegal to bank in specified states; Function may be legal in the bank indicated by Bank Address (BA), depending on the
state of that bank.
4. If both banks are idle, and CKE is inactive (Low), the device will enter Self-Refresh mode. All input buffers except CKE will
be disabled.
5. Illegal if tRCD is not satisfied.
6. Illegal if tRAS is not satisfied.
7. Must satisfy burst interrupt condition.
8. Must satisfy bus contention, bus turn around, and/or write recovery requirements.
9. Must mask preceding data which don’t satisfy tDPL.
10. Illegal if tRRD is not satisfied.
11. Illegal for single bank, but legal for other banks.
12
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
IS42S81600D,
IS42S16800D
CKE RELATED COMMAND TRUTH TABLE(1)
CKE
Current State
Self-Refresh (S.R.)
Self-Refresh Recovery
Power-Down(P.D.)
Both Banks Idle
Any state
other than
listed above
Operation
INVALID, CLK (n - 1) would exit S.R.
Self-Refresh Recovery(2)
Self-Refresh Recovery(2)
Illegal
Illegal
Maintain S.R.
Idle After tRC
Idle After tRC
Illegal
Illegal
Begin clock suspend next cycle(5)
Begin clock suspend next cycle(5)
Illegal
Illegal
Exit clock suspend next cycle(2)
Maintain clock suspend
INVALID, CLK (n - 1) would exit P.D.
EXIT P.D. --> Idle(2)
Maintain power down mode
Refer to operations in Operative Command Table
Refer to operations in Operative Command Table
Refer to operations in Operative Command Table
Auto-Refresh
Refer to operations in Operative Command Table
Refer to operations in Operative Command Table
Refer to operations in Operative Command Table
Refer to operations in Operative Command Table
Self-Refresh(3)
Refer to operations in Operative Command Table
Power-Down(3)
Refer to operations in Operative Command Table
Begin clock suspend next cycle(4)
Exit clock suspend next cycle
Maintain clock suspend
n-1
H
L
L
L
L
L
H
H
H
H
H
H
H
H
L
L
H
L
L
H
H
H
H
H
H
H
H
H
H
L
H
H
L
L
n
X
H
H
H
H
L
H
H
H
H
L
L
L
L
H
L
X
H
L
H
H
H
H
H
L
L
L
L
L
X
H
L
H
L
CS
X
H
L
L
L
X
H
L
L
L
H
L
L
L
X
X
X
X
X
H
L
L
L
L
H
L
L
L
L
X
X
X
X
X
RAS
X
X
H
H
L
X
X
H
H
L
X
H
H
L
X
X
X
X
X
X
H
L
L
L
X
H
L
L
L
X
X
X
X
X
CAS
X
X
H
L
X
X
X
H
L
X
X
H
L
X
X
X
X
X
X
X
X
H
L
L
X
X
H
L
L
X
X
X
X
X
WE
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
H
L
X
X
X
H
L
X
X
X
X
X
Address
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
—
X
X
—
—
—
X
Op - Code
—
—
—
X
Op - Code
X
X
X
X
X
Notes:
1. H : High level, L : low level, X : High or low level (Don’t care).
2. CKE Low to High transition will re-enable CLK and other inputs asynchronously. A minimum
setup time must be satisfied
before any command other than EXIT.
3. Power down and Self refresh can be entered only from the both banks idle state.
4. Must be legal command as defined in Operative Command Table.
5. Illegal if tSRX is not satisfied.
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
13
IS42S81600D,
IS42S16800D
STATE DIAGRAM
Self
Refresh
SELF
SELF exit
Mode
Register
Set
MRS
REF
IDLE
CBR (Auto)
Refresh
CKE
CKE
ACT
Power
Down
CKE
Row
Active
BST
BST
rge
th
ha
wi
ec
Pr
rite
to
W
h
wit
ad arge
h
ec
Read
Pr
Au
Re
CKE
to
Write
Read
Au
Write
WRITE
SUSPEND
Read
CKE
READ
WRITE
Write
CKE
CKE
tio
mi
ter
CKE
READA
SUSPEND
n)
tio
ina
PR
E(
Pr
ec
m
ter
POWER
ON
CKE
READA
ha
rge
rge
a
ch
CKE
Pre
WRITEA
na
E(
CKE
READ
SUSPEND
n)
RR
WRITEA
SUSPEND
Active
Power
Down
CKE
Precharge
Precharge
Automatic sequence
Manual Input
14
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
IS42S81600D,
IS42S16800D
ABSOLUTE MAXIMUM RATINGS(1)
Symbol
Parameters
VDD MAX
VDDQ MAX
VIN
VOUT
PD MAX
ICS
TOPR
Maximum Supply Voltage
Maximum Supply Voltage for Output Buffer
Input Voltage
Output Voltage
Allowable Power Dissipation
Output Shorted Current
Operating Temperature
Com.
Ind.
Storage Temperature
TSTG
Rating
Unit
–0.5 to +4.6
–0.5 to +4.6
–0.5 to VDD + 0.5
–1.0 to VDDQ + 0.5
1
50
0 to +70
–40 to +85
–55 to +150
V
V
V
V
W
mA
°C
°C
Notes:
1. Stress greater than those listed under ABSOLUTE MAXIMUM RATINGS may cause permanent damage to
the device. This is a stress rating only and functional operation of the device at these or any other conditions 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.
2. All voltages are referenced to Vss.
DC RECOMMENDED OPERATING CONDITIONS
Symbol
VDD
VDDQ
VIH(1)
VIL(2)
Parameter
Min.
Typ.
Max.
Unit
Supply Voltage
I/O Supply Voltage
Input High Voltage
Input Low Voltage
3.0
3.0
2.0
-0.3
3.3
3.3
—
—
3.6
3.6
VDDQ + 0.3
+0.8
V
V
V
V
Note:
1. VIH (max) = VDDQ +2V (PULSE WIDTH < 3NS).
2. VIL (min) = -2V (PULSE WIDTH < 3NS).
3. All voltages are referenced to Vss.
CAPACITANCE CHARACTERISTICS (At TA = 0 to +25°C, VDD = VDDQ = 3.3 ± 0.3V)
Symbol
Parameter
Min.
-6
CIN1
CIN2
CI/O
Input Capacitance: CLK
Input Capacitance:All other input pins
Data Input/Output Capacitance:I/Os
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
2.5
2.5
4.0
3.5
3.8
6.5
Max.
-7
-75E
4.0
5.0
6.5
4.0
5.0
6.5
Unit
pF
pF
pF
15
IS42S81600D,
IS42S16800D
DC ELECTRICAL CHARACTERISTICS 1 (Recommended Operation Conditions unless otherwise noted.)
Symbol
IDD1 (1)
Parameter
Operating Current
IDD2P
Precharge Standby Current
(In Power-Down Mode)
Precharge Standby Current
(In Power-Down Mode)
Precharge Standby Current
(In Non Power-Down Mode)
Precharge Standby Current
(In Non Power-Down Mode)
Active Standby Current
IDD2PS
IDD2N (2)
IDD2NS
IDD3N (2)
IDD3NS
IDD4
IDD5
IDD6
(In Non Power-Down Mode)
Active Standby Current
(In Non Power-Down Mode)
Operating Current
Auto-Refresh Current
Self-Refresh Current
Test Condition
One bank active, CL = 3, BL = 1,
tCLK = tCLK (min), tRC = tRC (min)
CKE ≤ VIL (MAX), tCK = 15ns
x8
x16
x8 / x16
-6
120
140
2
-7
100
120
2
CKE ≤ VIL (MAX), CLK ≤ VIL (MAX)
x8 / x16
1
1
1
mA
CS ≥ Vcc - 0.2V, CKE ≥ VIH (MIN)
tCK = 15ns
CS ≥ Vcc - 0.2V, CKE ≥ VIH (MIN) or
CKE ≤ VIL (MAX), All inputs stable
CS ≥ Vcc - 0.2V, CKE ≥ VIH (MIN)
x8 / x16
25
25
25
mA
x8 / x16
15
15
15
mA
x8 / x16
30
30
30
mA
x8 / x16
20
20
20
mA
x8
x16
x8
x8 / x16
170
180
180
2
120
130
160
2
tCK = 15ns
CS ≥ Vcc - 0.2V, CKE ≥ VIH (MIN) or
CKE ≤ VIL (MAX), All inputs stable
All banks active, BL = 4, CL = 3,
tCK = tCK (min)
tRC = tRC (min), tCLK = tCLK (min)
CKE ≤ 0.2V
-75E Unit
mA
120 mA
2
mA
130
2
mA
mA
mA
mA
Notes:
1. IDD (MAX) is specified at the output open condition.
2. Input signals are changed one time during 30ns.
DC ELECTRICAL CHARACTERISTICS 2 (Recommended Operation Conditions unless otherwise noted.)
Symbol
IIL
Parameter
Input Leakage Current
Test Condition
0V ≤ Vin ≤ Vcc, with pins other than
the tested pin at 0V
Min
-5
Max
5
Unit
μA
IOL
VOH
VOL
Output Leakage Current
Output High Voltage Level
Output Low Voltage Level
Output is disabled, 0V ≤ Vout ≤ Vcc,
IOH = -2mA
IOL = 2mA
-5
2.4
—
5
—
0.4
μA
V
V
16
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
IS42S81600D,
IS42S16800D
AC ELECTRICAL CHARACTERISTICS
(1,2,3)
-6
Symbol Parameter
-7
Min.
Max.
Min.
Max.
-75E
Min.
Max.
Units
tCK3
tCK2
Clock Cycle Time
CAS Latency = 3
CAS Latency = 2
6
8
—
—
7
10
—
—
—
7.5
—
—
ns
ns
tAC3
tAC2
Access Time From CLK
CAS Latency = 3
CAS Latency = 2
—
—
5.4
6.5
—
—
5.4
6.5
—
—
5.4
6.5
ns
ns
tCHI
CLK HIGH Level Width
2.5
—
2.5
—
2.5
—
ns
tCL
CLK LOW Level Width
2.5
—
2.5
—
2.5
—
ns
tOH3
tOH2
Output Data Hold Time
2.7
2.7
—
—
2.7
2.7
—
—
—
2.7
—
—
ns
ns
tLZ
Output LOW Impedance Time
0
—
0
—
0
—
ns
tHZ
Output HIGH Impedance Time
2.7
5.4
2.7
5.4
2.7
5.4
ns
tDS
Input Data Setup Time(2)
1.5
—
1.5
—
1.5
—
ns
tDH
Input Data Hold Time(2)
0.8
—
0.8
—
0.8
—
ns
1.5
—
1.5
—
1.5
—
ns
0.8
—
0.8
—
0.8
—
ns
1.5
—
1.5
—
1.5
—
ns
0.8
—
0.8
—
0.8
—
ns
1.5
—
1.5
—
1.5
—
ns
tAS
tAH
tCKS
CAS Latency = 3
CAS Latency = 2
(2)
Address Setup Time
Address Hold Time
(2)
(2)
CKE Setup Time
(2)
tCKH
CKE Hold Time
tCS
Command Setup Time (CS, RAS, CAS, WE, DQM)
tCH
Command Hold Time (CS, RAS, CAS, WE, DQM)(2)
0.8
—
0.8
—
0.8
—
ns
tRC
Command Period (REF to REF / ACT to ACT)
60
—
67.5
—
67.5
—
ns
tRAS
Command Period (ACT to PRE)
42
100K
45
100K
45
100K
ns
tRP
Command Period (PRE to ACT)
18
—
20
—
20
—
ns
tRCD
Active Command To Read / Write Command Delay Time
18
—
20
—
20
—
ns
tRRD
Command Period (ACT [0] to ACT[1])
12
—
14
—
15
—
ns
tDPL
Input Data To Precharge
Command Delay time
12
—
14
—
15
—
ns
tDAL
Input Data To Active / Refresh
Command Delay time (During Auto-Precharge)
27
—
35
—
35
—
ns
tMRD
Mode Register Program Time
12
—
15
—
15
—
ns
tDDE
Power Down Exit Setup Time
6
—
7.5
—
7.5
—
ns
tSRX
Self-Refresh Exit Time
6
—
7.5
—
7.5
—
ns
tT
Transition Time
1
10
1
10
1
10
ns
tREF
Refresh Cycle Time (4096)
—
64
—
64
—
64
ms
(2)
Notes:
1. The power-on sequence must be executed before starting memory operation.
2. Measured with tT = 1 ns. If clock rising time is longer than 1ns, (tR /2 - 0.5) ns should be added to the parameter.
3. The reference level is 1.4V when measuring input signal timing. Rise and fall times are measured between VIH(min.) and VIL (max).
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
17
IS42S81600D,
IS42S16800D
OPERATING FREQUENCY / LATENCY RELATIONSHIPS
SYMBOL PARAMETER
—
Clock Cycle Time
—
Operating Frequency (CAS Latency = 3)
tCAC
UNITS
6
7
7.5
ns
166
143
133
MHz
CAS Latency
3
3
3
cycle
tRCD
Active Command To Read/Write Command Delay Time
3
3
3
cycle
tRAC
RAS Latency (tRCD + tCAC)
6
6
6
cycle
tRC
Command Period (REF to REF / ACT to ACT)
10
10
10
cycle
tRAS
Command Period (ACT to PRE)
7
7
7
cycle
tRP
Command Period (PRE to ACT)
3
3
3
cycle
tRRD
Command Period (ACT[0] to ACT [1])
2
2
2
cycle
tCCD
Column Command Delay Time
(READ, READA, WRIT, WRITA)
1
1
1
cycle
tDPL
Input Data To Precharge Command Delay Time
2
2
2
cycle
tDAL
Input Data To Active/Refresh Command Delay Time
(During Auto-Precharge)
5
5
5
cycle
tRBD
Burst Stop Command To Output in HIGH-Z Delay Time
3
3
3
cycle
0
0
0
cycle
3
3
3
cycle
0
0
0
cycle
-2
–2
-2
cycle
CAS Latency = 3
CAS Latency = 3
(Read)
tWBD
Burst Stop Command To Input in Invalid Delay Time
(Write)
tRQL
Precharge Command To Output in HIGH-Z Delay Time
CAS Latency = 3
(Read)
tWDL
Precharge Command To Input in Invalid Delay Time
(Write)
tPQL
Last Output To Auto-Precharge Start Time (Read)
tQMD
DQM To Output Delay Time (Read)
2
2
2
cycle
tDMD
DQM To Input Delay Time (Write)
0
0
0
cycle
tMRD
Mode Register Set To Command Delay Time
2
2
2
cycle
18
CAS Latency = 3
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
IS42S81600D,
IS42S16800D
AC TEST CONDITIONS
Input Load
Output Load
tCK
tCL
tCHI
3.0V
CLK 1.4V
1.4V
0V
50Ω
Z = 50Ω
tCS
tCH
Output
3.0V
50 pF
INPUT 1.4V
0V
tAC
tOH
OUTPUT
1.4V
1.4V
AC TEST CONDITIONS
Parameter
AC Input Levels
Input Rise and Fall Times
Input Timing Reference Level
Output Timing Measurement Reference Level
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
Rating
0V to 3.0V
1 ns
1.4V
1.4V
19
IS42S81600D,
IS42S16800D
FUNCTIONAL DESCRIPTION
Initialization
The 128Mb SDRAMs are quad-bank DRAMs which operate
at 3.3V and include a synchronous interface (all signals are
registered on the positive edge of the clock signal, CLK).
Each of the 33,554,432-bit banks is organized as 4,096
rows by 512 columns by 16 bits or 4,096 rows by 1,024
columns by 8 bits.
Read and write accesses to the SDRAM are burst oriented;
accesses start at a selected location and continue for a
programmed number of locations in a programmed
sequence. Accesses begin with the registration of an ACTIVE command which is then followed by a READ or WRITE
command. The address bits registered coincident with the
ACTIVE command are used to select the bank and row to
be accessed (BA0 and BA1 select the bank, A0-A11 select the row).
The address bits A0-A9 (x8); A0-A8 (x16) registered coincident
with the READ or WRITE command are used to select the
starting column location for the burst access.
Prior to normal operation, the SDRAM must be initialized.
The following sections provide detailed information covering
device initialization, register definition, command
descriptions and device operation.
SDRAMs must be powered up and initialized in a
predefined manner.
The 128M SDRAM is initialized after the power is applied to
VDD and VDDQ (simultaneously) and the clock is stable with
DQM High and CKE High.
A 100µs delay is required prior to issuing any command
other than a COMMAND INHIBIT or a NOP. The COMMAND
INHIBIT or NOP may be applied during the 100us period and
should continue at least through the end of the period.
With at least one COMMAND INHIBIT or NOP command
having been applied, a PRECHARGE command should be
applied once the 100µs delay has been satisfied. All banks
must be precharged. This will leave all banks in an idle state
after which at least two AUTO REFRESH cycles must be
performed. After the AUTO REFRESH cycles are complete,
the SDRAM is then ready for mode register programming.
The mode register should be loaded prior to applying any
operational command because it will power up in an unknown state.
20
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IS42S81600D,
IS42S16800D
INITIALIZE AND LOAD MODE REGISTER(1)
T0
T1
Tn+1
tCH
tCK
CLK
To+1
tCL
Tp+1
Tp+2
Tp+3
tCKS tCKH
CKE
COMMAND
tCMH tCMS
tCMH tCMS
tCMH tCMS
NOP
PRECHARGE
AUTO
REFRESH
NOP
AUTO
REFRESH
NOP
Load MODE
REGISTER
NOP
ACTIVE
DQM/
DQML, DQMH
tAS tAH
A0-A9, A11
ALL BANKS
A10
SINGLE BANK
BA0, BA1
CODE
tAS tAH
ROW
CODE
ROW
tAS tAH
ALL BANKS
BANK
CODE
DQ
tRP
tRC
tRC
tMRD
T
Power-up: VCC
and CLK stable
Precharge
all banks
AUTO REFRESH
AUTO REFRESH
T = 100µs Min.
Program MODE REGISTER (2, 3, 4)
DON'T CARE
Notes:
1. If CS is High at clock High time, all commands applied are NOP.
2. The Mode register may be loaded prior to the Auto-Refresh cycles if desired.
3. JEDEC and PC100 specify three clocks.
4. Outputs are guaranteed High-Z after the command is issued.
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21
IS42S81600D,
IS42S16800D
AUTO-REFRESH CYCLE
T0
T1
tCK
CLK
T2
tCL
Tn+1
To+1
tCH
tCKS tCKH
CKE
tCMS tCMH
COMMAND
PRECHARGE
NOP
Auto
Refresh
NOP
Auto
Refresh
NOP
ACTIVE
DQM/
DQML, DQMH
A0-A9, A11
ROW
ALL BANKS
A10
ROW
SINGLE BANK
BA0, BA1
DQ
BANK
BANK(s)
tAS tAH
High-Z
tRP
tRC
tRC
DON'T CARE
Notes:
1. CAS latency = 2, 3
22
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Rev. E
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IS42S81600D,
IS42S16800D
SELF-REFRESH CYCLE
T0
T1
tCK
CLK
T2
tCH
tCKS tCKH
Tn+1
To+1
To+2
tCL
tCKS
≥ tRAS
CKE
tCKS
tCMS tCMH
COMMAND
PRECHARGE
NOP
Auto
Refresh
NOP
NOP
Auto
Refresh
DQM/
DQML, DQMH
A0-A9, A11
ALL BANKS
A10
SINGLE BANK
tAS tAH
BA0, BA1
BANK
DQ High-Z
tRP
Precharge all
active banks
Enter self
refresh mode
tSRX
CLK stable prior to exiting
Exit self refresh mode
self refresh mode
(Restart refresh time base)
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DON'T CARE
23
IS42S81600D,
IS42S16800D
REGISTER DEFINITION
Mode Register
Mode register bits M0-M2 specify the burst length, M3
specifies the type of burst (sequential or interleaved), M4- M6
specify the CAS latency, M7 and M8 specify the operating
mode, M9 specifies the WRITE burst mode, and M10 and
M11 are reserved for future use.
The mode register must be loaded when all banks are idle,
and the controller must wait the specified time before
initiating the subsequent operation. Violating either of these
requirements will result in unspecified operation.
The mode register is used to define the specific mode of
operation of the SDRAM. This definition includes the
selection of a burst length, a burst type, a CAS latency, an
operating mode and a write burst mode, as shown in MODE
REGISTER DEFINITION.
The mode register is programmed via the LOAD MODE
REGISTER command and will retain the stored information
until it is programmed again or the device loses power.
MODE REGISTER DEFINITION
BA1 BA0 A11 A10
A9
A8
A7
A6
A5
A4
A3
A2
A1
A0
Address Bus
Mode Register (Mx)
(1)
Burst Length
Reserved
M2
M1 M0
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
M3=0
M3=1
1
2
4
8
Reserved
Reserved
Reserved
Full Page
1
2
4
8
Reserved
Reserved
Reserved
Reserved
Burst Type
M3
Type
0
1
Sequential
Interleaved
Latency Mode
M6 M5 M4
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
CAS Latency
Reserved
Reserved
2
3
Reserved
Reserved
Reserved
Reserved
Operating Mode
M8 M7
M6-M0
Mode
0 0
— —
Defined
—
Standard Operation
All Other States Reserved
Write Burst Mode
M9
0
1
24
Mode
Programmed Burst Length
Single Location Access
1. To ensure compatibility with future devices,
should program BA1, BA0, A11, A10 = "0"
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IS42S81600D,
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BURST LENGTH
Read and write accesses to the SDRAM are burst oriented,
with the burst length being programmable, as shown in
MODE REGISTER 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 1, 2, 4 or 8 locations are available for both the
sequential and the interleaved burst types, and a full-page
burst is available for the sequential type. The full-page burst
is used in conjunction with the BURST TERMINATE command to generate arbitrary burst lengths.
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, mean-
ing that the burst will wrap within the block if a boundary is
reached. The block is uniquely selected by A1-A8 (x16)
when the burst length is set to two; by A2-A8 (x16) when the
burst length is set to four; and by A3-A8 (x16) when the burst
length is set to eight. The remaining (least significant)
address bit(s) is (are) used to select the starting location
within the block. Full-page bursts wrap within the page if the
boundary is reached.
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 address,
as shown in BURST DEFINITION table.
BURST DEFINITION
Burst
Starting Column
Length
Address
Order of Accesses Within a Burst
Type = Sequential
Type = Interleaved
0
0-1
0-1
1
1-0
1-0
A0
2
A1
A0
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
A2
A1
A0
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
Cn, Cn + 1, Cn + 2
Cn + 3, Cn + 4...
…Cn - 1,
Cn…
Not Supported
4
8
Full
Page
(y)
n = A0-A7
(location 0-y)
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25
IS42S81600D,
IS42S16800D
CAS Latency
Operating Mode
The CAS latency is the delay, in clock cycles, between the
registration of a READ command and the availability of the
first piece of output data. The latency can be set to two or
three clocks.
If a READ command is registered at clock edge n, and the
latency is m clocks, the data will be available by clock edge
n + m. The DQs will start driving as a result of the clock edge
one cycle earlier (n + m - 1), and provided that the relevant
access times are met, the data will be valid by clock edge
n + m. For example, assuming that the clock cycle time is
such that all relevant access times are met, if a READ
command is registered at T0 and the latency is programmed
to two clocks, the DQs will start driving after T1 and the data
will be valid by T2, as shown in CAS Latency diagrams. The
Allowable Operating Frequency table indicates the operating frequencies at which each CAS latency setting can be
used.
Reserved states should not be used as unknown operation or
incompatibility with future versions may result.
The normal operating mode is selected by setting M7 and M8
to zero; the other combinations of values for M7 and M8 are
reserved for future use and/or test modes. The programmed
burst length applies to both READ and WRITE bursts.
Test modes and reserved states should not be used
because unknown operation or incompatibility with future
versions may result.
Write Burst Mode
When M9 = 0, the burst length programmed via M0-M2
applies to both READ and WRITE bursts; when M9 = 1, the
programmed burst length applies to READ bursts, but write
accesses are single-location (nonburst) accesses.
CAS Latency
Allowable Operating Frequency (MHz)
Speed
CAS Latency = 2
CAS Latency = 3
-6
125
166
-7
100
143
-75E
133
—
CAS LATENCY
T0
T1
T2
T3
READ
NOP
NOP
CLK
COMMAND
tAC
DOUT
DQ
tOH
tLZ
CAS Latency - 2
T0
T1
T2
T3
T4
READ
NOP
NOP
NOP
CLK
COMMAND
tAC
DOUT
DQ
tLZ
tOH
CAS Latency - 3
DON'T CARE
UNDEFINED
26
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IS42S81600D,
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ACTIVATING SPECIFIC ROW WITHIN SPECIFIC BANK
CHIP OPERATION
BANK/ROW ACTIVATION
Before any READ or WRITE commands can be issued to a
bank within the 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 (see
Activating Specific Row Within Specific Bank).
After opening a row (issuing an ACTIVE command), a
READ or WRITE command may be issued to that row,
subject to the tRCD specification. Minimum tRCD 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. For example, a tRCD specification of 18ns
with a 125 MHz clock (8ns period) results in 2.25 clocks,
rounded to 3. This is reflected in the following example,
which covers any case where 2 < [tRCD (MIN)/tCK] ≤ 3. (The
same procedure is used to convert other specification limits
from time units to clock cycles).
A subsequent ACTIVE command to a different row in the
same bank can only be issued after the previous active row
has been “closed” (precharged). The minimum time interval
between successive ACTIVE commands to the same bank
is defined by tRC.
CLK
HIGH
CKE
CS
RAS
CAS
WE
A0-A11
ROW ADDRESS
BA0, BA1
BANK ADDRESS
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.
EXAMPLE: MEETING TRCD (MIN) WHEN 2 < [TRCD (MIN)/TCK] ≤ 3
T0
T1
T2
ACTIVE
NOP
NOP
T3
T4
CLK
COMMAND
READ or
WRITE
tRCD
DON'T CARE
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27
IS42S81600D,
IS42S16800D
READS
READ bursts are initiated with a READ command, as shown
in the READ COMMAND diagram.
The starting column and bank addresses are provided with the
READ command, and auto precharge is either enabled or
disabled for that burst access. If auto precharge is enabled, the
row being accessed is precharged at the completion of the
burst. For the generic READ commands used in the following
illustrations, auto precharge is disabled.
During READ bursts, the valid data-out element from the
starting column address will be available following the CAS
latency after the READ command. Each subsequent dataout element will be valid by the next positive clock edge. The
CAS Latency diagram shows general timing
for each possible CAS latency setting.
Upon completion of a burst, assuming no other commands
have been initiated, the DQs will go High-Z. A full-page burst
will continue until terminated. (At the end of the page, it will
wrap to column 0 and continue.)
Data from any READ burst may be truncated with a subsequent READ command, and data from a fixed-length READ
burst may be immediately followed by data from a READ
command. In either case, a continuous flow of data can be
maintained. The first data element from the new burst follows
either the last element of a completed burst or the last desired
data element of a longer burst which is being truncated.
The new READ command should be issued x cycles before
the clock edge at which the last desired data element is
valid, where x equals the CAS latency minus one. This is
shown in Consecutive READ Bursts for CAS latencies of
two and three; data element n + 3 is either the last of a burst
of four or the last desired of a longer burst. The 128Mb
SDRAM uses a pipelined architecture and therefore does
not require the 2n rule associated with a prefetch architecture. A READ command can be initiated on any clock cycle
following a previous READ command. Full-speed random
read accesses can be performed to the same bank, as shown
in Random READ Accesses, or each subsequent READ
may be performed to a different bank.
Data from any READ burst may be truncated with a
subsequent WRITE command, and data from a fixed-length
READ burst may be immediately followed by data from a
WRITE command (subject to bus turnaround limitations).
The WRITE burst may be initiated on the clock edge
immediately following the last (or last desired) data element
from the READ burst, provided that I/O contention can be
avoided. In a given system design, there may be a possibility that the device driving the input data will go Low-Z
before the SDRAM DQs go High-Z. In this case, at least a
single-cycle delay should occur between the last read data
and the WRITE command.
28
READ COMMAND
CLK
HIGH
CKE
CS
RAS
CAS
WE
A0-A9
COLUMN ADDRESS
A11
AUTO PRECHARGE
A10
NO PRECHARGE
BA0, BA1
BANK ADDRESS
Note: A9 is "Don't Care" for x16.
The DQM input is used to avoid I/O contention, as shown
in Figures RW1 and RW2. The DQM signal must be
asserted (HIGH) at least three clocks prior to the WRITE
command (DQM latency is two clocks for output buffers) to
suppress data-out from the READ. Once the WRITE command is registered, the DQs will go High-Z (or remain HighZ), regardless of the state of the DQM signal, provided the
DQM was active on the clock just prior to the WRITE
command that truncated the READ command. If not, the
second WRITE will be an invalid WRITE. For example, if
DQM was LOW during T4 in Figure RW2, then the WRITEs
at T5 and T7 would be valid, while the WRITE at T6 would
be invalid.
The DQM signal must be de-asserted prior to the WRITE
command (DQM latency is zero clocks for input buffers) to
ensure that the written data is not masked.
A fixed-length READ burst may be followed by, or truncated
with, a PRECHARGE command to the same bank (provided
that auto precharge was not activated), and a full-page burst
may be truncated with a PRECHARGE command to the
same bank. The PRECHARGE command should be issued
x cycles before the clock edge at which the last desired data
element is valid, where x equals the CAS latency minus one.
This is shown in the READ to PRECHARGE diagram for each
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IS42S81600D,
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possible CAS latency; data element n + 3 is either the last of
a burst of four or the last desired of a longer burst. Following
the PRECHARGE command, a subsequent command to the
same bank cannot be issued until tRP is met. Note that part
of the row precharge time is hidden during the access of the
last data element(s).
In the case of a fixed-length burst being executed to
completion, a PRECHARGE command issued at the optimum time (as described above) provides the same operation that would result from the same fixed-length burst with
auto precharge. The disadvantage of the PRECHARGE
command is that it requires that the command and address
buses be available at the appropriate time to issue the
command; the advantage of the PRECHARGE command is
that it can be used to truncate fixed-length or full-page
bursts.
Full-page READ bursts can be truncated with the BURST
TERMINATE command, and fixed-length READ bursts
may be truncated with a BURST TERMINATE command,
provided that auto precharge was not activated. The BURST
TERMINATE command should be issued x cycles before
the clock edge at which the last desired data element is
valid, where x equals the CAS latency minus one. This is
shown in the READ Burst Termination diagram for each
possible CAS latency; data element n + 3 is the last desired
data element of a longer burst.
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Rev. E
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29
IS42S81600D,
IS42S16800D
RW1 - READ to WRITE
T0
T1
T2
T3
T4
T5
T6
COMMAND
READ
NOP
NOP
NOP
NOP
NOP
WRITE
ADDRESS
BANK,
COL n
CLK
DQM
BANK,
COL b
tHZ
DOUT n
DQ
DOUT n+1
DIN b
DOUT n+2
CAS Latency - 2
tDS
DON'T CARE
RW2 - READ to WRITE
T0
T1
T2
T3
T4
T5
COMMAND
READ
NOP
NOP
NOP
NOP
WRITE
ADDRESS
BANK,
COL n
CLK
DQM
BANK,
COL b
tHZ
DQ
DOUT n
CAS Latency - 3
DIN b
tDS
DON'T CARE
30
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Rev. E
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IS42S81600D,
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CONSECUTIVE READ BURSTS
T0
T1
T2
T3
T4
T5
T6
COMMAND
READ
NOP
NOP
NOP
READ
NOP
NOP
ADDRESS
BANK,
COL n
DOUT n+3
DOUT b
CLK
BANK,
COL b
DQ
DOUT n
DOUT n+1
DOUT n+2
CAS Latency - 2
DON'T CARE
T0
T1
T2
T3
T4
T5
T6
T7
COMMAND
READ
NOP
NOP
NOP
READ
NOP
NOP
NOP
ADDRESS
BANK,
COL n
DOUT n+2
DOUT n+3
DOUT b
CLK
BANK,
COL b
DQ
DOUT n
DOUT n+1
CAS Latency - 3
DON'T CARE
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IS42S81600D,
IS42S16800D
RANDOM READ ACCESSES
T0
T1
T2
T3
T4
T5
COMMAND
READ
READ
READ
READ
NOP
NOP
ADDRESS
BANK,
COL n
BANK,
COL b
BANK,
COL m
BANK,
COL x
CLK
DQ
DOUT n
DOUT b
DOUT m
DOUT x
CAS Latency - 2
DON'T CARE
T0
T1
T2
T3
T4
T5
T6
COMMAND
READ
READ
READ
READ
NOP
NOP
NOP
ADDRESS
BANK,
COL n
BANK,
COL b
BANK,
COL m
BANK,
COL x
CLK
DQ
DOUT n
DOUT b
DOUT m
DOUT x
CAS Latency - 3
DON'T CARE
32
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IS42S81600D,
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READ BURST TERMINATION
T0
T1
T2
T3
T4
READ
NOP
NOP
NOP
T5
T6
NOP
NOP
CLK
COMMAND
BURST
TERMINATE
x = 1 cycle
BANK a,
COL n
ADDRESS
DQ
DOUT n
DOUT n+1
DOUT n+2
DOUT n+3
CAS Latency - 2
DON'T CARE
T0
T1
T2
T3
READ
NOP
NOP
NOP
T4
T5
T6
T7
NOP
NOP
NOP
CLK
COMMAND
BURST
TERMINATE
x = 2 cycles
ADDRESS
BANK,
COL n
DQ
DOUT n
DOUT n+1
DOUT n+2
DOUT n+3
CAS Latency - 3
DON'T CARE
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IS42S81600D,
IS42S16800D
ALTERNATING BANK READ ACCESSES
T0
T1
tCK
CLK
T2
tCL
T3
T4
T5
T6
T7
T8
NOP
READ
NOP
tCH
tCKS tCKH
CKE
tCMS tCMH
COMMAND
ACTIVE
NOP
READ
NOP
ACTIVE
ACTIVE
tCMS tCMH
DQM/
DQML, DQMH
tAS tAH
A0-A9, A11
ROW
tAS tAH
A10
ROW
tAS tAH
BA0, BA1
BANK 0
COLUMN m(2)
COLUMN b(2)
ROW
ENABLE AUTO PRECHARGE
ROW
ENABLE AUTO PRECHARGE
ROW
BANK 0
ROW
BANK 3
tLZ
BANK 3
tOH
tOH
DQ
DOUT m
tAC
tRCD - BANK 0
tRRD
tOH
DOUT m+1
tAC
BANK 0
tAC
tOH
DOUT m+2
tOH
DOUT m+3
tAC
tAC
tRP - BANK 0
CAS Latency - BANK 0
tRCD - BANK 3
DOUT b
tAC
tRCD - BANK 0
CAS Latency - BANK 3
tRAS - BANK 0
tRC - BANK 0
DON'T CARE
Notes:
1) CAS latency = 2, Burst Length = 4
2) X16: A9 and A11 = "Don't Care"
X8: A11 = "Don't Care"
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IS42S81600D,
IS42S16800D
READ - FULL-PAGE BURST
T0
T1
tCK
CLK
T2
tCL
T3
T4
T5
T6
Tn+1
NOP
NOP
NOP
NOP
Tn+2
Tn+3
Tn+4
NOP
NOP
tCH
tCKS tCKH
CKE
tCMS tCMH
COMMAND
ACTIVE
NOP
READ
NOP
BURST TERM
tCMS tCMH
DQM/
DQML, DQMH
tAS tAH
A0-A9, A11
ROW
tAS tAH
A10
ROW
tAS tAH
BA0, BA1
BANK
COLUMN m(2)
BANK
tAC
DQ
tLZ
tRCD
CAS Latency
tAC
DOUT m
tAC
DOUT m+1
tOH
tOH
each row (x4) has
1,024 locations
tAC
DOUT m+2
tAC
DOUT m-1
tAC
DOUT m
tHZ
DOUT m+1
tOH
tOH
tOH
tOH
DON'T CARE
Full page Full-page burst not self-terminating.
completion Use BURST TERMINATE command.
UNDEFINED
Notes:
1) CAS latency = 2, Burst Length = Full Page
2) X16: A9 and A11 = "Don't Care"
X8: A11 = "Don't Care"
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
35
IS42S81600D,
IS42S16800D
READ - DQM OPERATION
T0
T1
T2
tCK
CLK
tCL
T3
T4
T5
T6
T7
T8
NOP
NOP
NOP
NOP
NOP
NOP
tCH
tCKS tCKH
CKE
tCMS tCMH
COMMAND
ACTIVE
NOP
READ
tCMS tCMH
DQM/
DQML, DQMH
tAS tAH
COLUMN m(2)
A0-A9, A11
ROW
tAS tAH
A10
ROW
tAS tAH
DISABLE AUTO PRECHARGE
BANK
BANK
BA0, BA1
ENABLE AUTO PRECHARGE
tAC
DQ
tLZ
tRCD
CAS Latency
tOH
tAC
DOUT m
tHZ
tLZ
tOH
DOUT m+2
tAC
tOH
DOUT m+3
tHZ
DON'T CARE
UNDEFINED
Notes:
1) CAS latency = 2, Burst Length = 4
2) X16: A9 and A11 = "Don't Care"
X8: A11 = "Don't Care"
36
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
IS42S81600D,
IS42S16800D
READ to PRECHARGE
T0
T1
T2
T3
T4
T5
T6
T7
CLK
tRP
COMMAND
READ
ADDRESS
BANK a,
COL n
NOP
NOP
NOP
PRECHARGE
NOP
ACTIVE
BANK
(a or all)
BANK a,
ROW
tRQL
DQ
DOUT n
DOUT n+1
DOUT n+2
NOP
High-Z
DOUT n+3
CAS Latency - 2
DON'T CARE
T0
T1
T2
T3
T4
T5
T6
T7
CLK
tRP
COMMAND
READ
ADDRESS
BANK,
COL n
NOP
NOP
NOP
PRECHARGE
NOP
NOP
BANK,
COL b
BANK a,
ROW
tRQL
DQ
DOUT n
DOUT n+1
ACTIVE
DOUT n+2
High-Z
DOUT n+3
CAS Latency - 3
DON'T CARE
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
37
IS42S81600D,
IS42S16800D
WRITES
WRITE bursts are initiated with a WRITE command, as
shown in WRITE Command diagram.
WRITE COMMAND
CLK
HIGH
CKE
CS
RAS
CAS
WE
A0-A9
COLUMN ADDRESS
A11
AUTO PRECHARGE
A10
NO PRECHARGE
BA0, BA1
BANK ADDRESS
Note: A9 is "Don't Care" for x16.
The starting column and bank addresses are provided with
the WRITE command, and auto precharge is either enabled
or disabled for that access. If auto precharge is enabled, the
row being accessed is precharged at the completion of the
burst. For the generic WRITE commands used in the
following illustrations, auto precharge is disabled.
During WRITE bursts, the first valid data-in element will be
registered coincident with the WRITE command. Subsequent
data elements will be registered on each successive positive
clock edge. Upon completion of a fixed-length burst, assuming no other commands have been initiated, the DQs will
remain High-Z and any additional input data will be ignored
(see WRITE Burst). A full-page burst will continue until
terminated. (At the end of the page, it will wrap to column 0
and continue.)
Data for any WRITE burst may be truncated with a subsequent WRITE command, and data for a fixed-length WRITE
burst may be immediately followed by data for a WRITE
command. The new WRITE command can be issued on any
clock following the previous WRITE command, and the data
provided coincident with the new command applies to the new
command.
38
An example is shown in WRITE to WRITE diagram. Data n
+ 1 is either the last of a burst of two or the last desired of
a longer burst. The 128Mb SDRAM uses a pipelined
architecture and therefore does not require the 2n rule
associated with a prefetch architecture. A WRITE command
can be initiated on any clock cycle following a previous
WRITE command. Full-speed random write accesses within
a page can be performed to the same bank, as shown in
Random WRITE Cycles, or each subsequent WRITE may
be performed to a different bank.
Data for any WRITE burst may be truncated with a subsequent READ command, and data for a fixed-length WRITE
burst may be immediately followed by a subsequent READ
command. Once the READ com mand is registered, the
data inputs will be ignored, and WRITEs will not be executed. An example is shown in WRITE to READ. Data n +
1 is either the last of a burst of two or the last desired of a
longer burst.
Data for a fixed-length WRITE burst may be followed by, or
truncated with, a PRECHARGE command to the same bank
(provided that auto precharge was not activated), and a fullpage WRITE burst may be truncated with a PRECHARGE
command to the same bank. The PRECHARGE command
should be issued tDPL after the clock edge at which the last
desired input data element is registered. The auto precharge
mode requires a tDPL of at least one clock plus time,
regardless of frequency. In addition, when truncating a
WRITE burst, the DQM signal must be used to mask input
data for the clock edge prior to, and the clock edge coincident
with, the PRECHARGE command. An example is shown in the
WRITE to PRECHARGE diagram. Data n+1 is either the last
of a burst of two or the last desired of a longer burst. Following
the PRECHARGE command, a subsequent command to the
same bank cannot be issued until tRP is met.
In the case of a fixed-length burst being executed to completion, a PRECHARGE command issued at the optimum time (as
described above) provides the same operation that would result
from the same fixed-length burst with auto precharge. The
disadvantage of the PRECHARGE command is that it requires
that the command and address buses be available at the
appropriate time to issue the command; the advantage of the
PRECHARGE command is that it can be used to truncate
fixed-length or full-page bursts.
Fixed-length or full-page WRITE bursts can be truncated
with the BURST TERMINATE command. When truncating
a WRITE burst, the input data applied coincident with the
BURST TERMINATE command will be ignored. The last
data written (provided that DQM is LOW at that time) will be
the input data applied one clock previous to the BURST
TERMINATE command. This is shown in WRITE Burst
Termination, where data n is the last desired data element
of a longer burst.
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
IS42S81600D,
IS42S16800D
WRITE BURST
T0
T1
T2
T3
COMMAND
WRITE
NOP
NOP
NOP
ADDRESS
BANK,
COL n
CLK
DQ
DIN n
DIN n+1
DON'T CARE
WRITE TO WRITE
T0
T1
T2
COMMAND
WRITE
NOP
WRITE
ADDRESS
BANK,
COL n
CLK
DQ
BANK,
COL b
DIN n
DIN n+1
DIN b
DON'T CARE
RANDOM WRITE CYCLES
T0
T1
T2
T3
COMMAND
WRITE
WRITE
WRITE
WRITE
ADDRESS
BANK,
COL n
BANK,
COL b
BANK,
COL m
BANK,
COL x
DIN b
DIN m
DIN x
CLK
DQ
DIN n
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
39
IS42S81600D,
IS42S16800D
WRITE to READ
T0
T1
T2
T3
T4
T5
COMMAND
WRITE
NOP
READ
NOP
NOP
NOP
ADDRESS
BANK,
COL n
DOUT b
DOUT b+1
CLK
DQ
BANK,
COL b
DIN n
DIN n+1
CAS Latency - 2
DON'T CARE
WP1 - WRITE to PRECHARGE
T0
T1
T2
T3
T4
T5
T6
CLK
DQM
tRP
COMMAND
WRITE
ADDRESS
BANK a,
COL n
NOP
NOP
PRECHARGE
BANK
(a or all)
NOP
ACTIVE
NOP
BANK a,
ROW
tDPL
DQ
DIN n
DIN n+1
DIN n+2
DON'T CARE
40
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
IS42S81600D,
IS42S16800D
WP2 - WRITE to PRECHARGE
T0
T1
T2
T3
T4
T5
T6
CLK
DQM
tRP
COMMAND
WRITE
ADDRESS
BANK a,
COL n
NOP
NOP
PRECHARGE
NOP
BANK
(a or all)
NOP
ACTIVE
BANK a,
ROW
tDPL
DQ
DIN n
DIN n+1
DON'T CARE
WRITE Burst Termination
T0
T1
T2
COMMAND
WRITE
BURST
TERMINATE
NEXT
COMMAND
ADDRESS
BANK,
COL n
CLK
DQ
DIN n
(ADDRESS)
(DATA)
DON'T CARE
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
41
IS42S81600D,
IS42S16800D
WRITE - FULL PAGE BURST
T0
T1
tCK
CLK
T2
tCL
T3
T4
T5
Tn+1
Tn+2
NOP
NOP
NOP
NOP
BURST TERM
tDS tDH
tDS tDH
tDS
DIN m+1
DIN m+2
DIN m+3
tCH
tCKS tCKH
CKE
tCMS tCMH
COMMAND
ACTIVE
NOP
WRITE
NOP
tCMS tCMH
DQM/DQML
DQMH
tAS tAH
A0-A9, A11
ROW
tAS tAH
A10
ROW
tAS tAH
BA0, BA1
BANK
COLUMN m(2)
BANK
tDS
tDH
DIN m
DQ
tRCD
tDH
tDS
tDH
tDS
tDH
DIN m-1
Full page completed
DON'T CARE
Notes:
1) Burst Length = Full Page
2) X16: A9 and A11 = "Don't Care"
X8: A11 = "Don't Care"
42
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
IS42S81600D,
IS42S16800D
WRITE - DQM OPERATION
T0
T1
T2
tCK
CLK
tCL
T3
T4
T5
T6
T7
NOP
NOP
NOP
NOP
NOP
tCH
tCKS tCKH
CKE
tCMS tCMH
COMMAND
ACTIVE
NOP
WRITE
tCMS tCMH
DQM/DQML
DQMH
tAS tAH
A0-A9, A11
A10
BA0, BA1
COLUMN m(2)
ROW
tAS tAH
ENABLE AUTO PRECHARGE
ROW
tAS tAH
DISABLE AUTO PRECHARGE
BANK
BANK
tDS
tDH
DIN m
DQ
tRCD
tDS tDH
tDS
tDH
DIN m+2
DIN m+3
DON'T CARE
Notes:
1) Burst Length = 4
2) X16: A9 and A11 = "Don't Care"
X8: A11 = "Don't Care"
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
43
IS42S81600D,
IS42S16800D
ALTERNATING BANK WRITE ACCESSES
T0
T1
tCK
CLK
T2
tCL
T3
T4
T5
T6
T7
T8
T9
NOP
NOP
tCH
tCKS tCKH
CKE
tCMS tCMH
COMMAND
ACTIVE
NOP
WRITE
NOP
ACTIVE
NOP
WRITE
ACTIVE
tCMS tCMH
DQM/DQML
DQMH
tAS tAH
A0-A9, A11
ROW
tAS tAH
A10
ROW
tAS tAH
BA0, BA1
BANK 0
COLUMN m(2)
COLUMN b(2)
ROW
ENABLE AUTO PRECHARGE
ROW
ENABLE AUTO PRECHARGE
ROW
BANK 0
tDS
DQ
tDH
DIN m
tRCD - BANK 0
tRRD
tRAS - BANK 0
tRC - BANK 0
ROW
BANK 1
tDS tDH
DIN m+1
BANK 1
tDS
tDS tDH
DIN m+2
tDH
DIN m+3
tDS
tDH
DIN b
tDPL - BANK 0
tRCD - BANK 1
BANK 0
tDS
tDH
DIN b+1
tDS
tDH
DIN b+2
tRP - BANK 0
tDS
tDH
DIN b+3
tRCD - BANK 0
tDPL - BANK 1
DON'T CARE
Notes:
1) Burst Length = 4
2) X16: A9 and A11 = "Don't Care"
X8: A11 = "Don't Care"
44
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
IS42S81600D,
IS42S16800D
CLOCK SUSPEND
Clock suspend mode occurs when a column access/burst
is in progress and CKE is registered LOW. In the clock
suspend mode, the internal clock is deactivated, “freezing”
the synchronous logic.
For each positive clock edge on which CKE is sampled
LOW, the next internal positive clock edge is suspended.
Clock Suspend During WRITE Burst
T0
T1
NOP
WRITE
Any command or data present on the input pins at the time
of a suspended internal clock edge is ignored; any data
present on the DQ pins remains driven; and burst counters
are not incremented, as long as the clock is suspended.
(See following examples.)
Clock suspend mode is exited by registering CKE HIGH; the
internal clock and related operation will resume on the
subsequent positive clock edge.
T2
T3
T4
T5
NOP
NOP
DIN n+1
DIN n+2
CLK
CKE
INTERNAL
CLOCK
COMMAND
BANK a,
COL n
ADDRESS
DQ
DIN n
DON'T CARE
Clock Suspend During READ Burst
T0
T1
T2
COMMAND
READ
NOP
NOP
ADDRESS
BANK a,
COL n
T3
T4
T5
T6
NOP
NOP
NOP
CLK
CKE
INTERNAL
CLOCK
DQ
DOUT n
DOUT n+1
DOUT n+2
DOUT n+3
DON'T CARE
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Rev. E
07/28/08
45
IS42S81600D,
IS42S16800D
CLOCK SUSPEND MODE
T0
T1
tCK
CLK
T2
tCL
tCKS tCKH
T3
T4
T5
T6
NOP
NOP
NOP
T7
T8
T9
tCH
tCKS tCKH
CKE
tCMS tCMH
COMMAND
READ
NOP
NOP
WRITE
NOP
tCMS tCMH
DQM/DQML
DQMH
tAS tAH
A0-A9, A11
COLUMN m(2)
tAS tAH
COLUMN n(2)
A10
tAS tAH
BA0, BA1
BANK
BANK
tAC
tAC
DOUT m
DQ
tLZ
tHZ
DOUT m+1
tDS
tDH
DIN e
DIN e+1
tOH
DON'T CARE
UNDEFINED
Notes:
1) CAS latency = 3, Burst Length = 2, Auto Precharge is disabled.
2) X16: A9 and A11 = "Don't Care"
X8: A11 = "Don't Care"
46
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
IS42S81600D,
IS42S16800D
PRECHARGE
PRECHARGE Command
The PRECHARGE command (see figure) is used to deactivate the open row in a particular bank or the open row in all
banks. The bank(s) will be available for a subsequent row
access some specified time (tRP) after the PRECHARGE
command is issued. Input A10 determines whether one or
all banks are to be precharged, and in the case where only
one bank is to be precharged, inputs BA0, BA1 select the
bank. When all banks are to be precharged, inputs 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.
CLK
HIGH
CKE
CS
RAS
CAS
WE
POWER-DOWN
Power-down occurs if CKE is registered LOW coincident
with a NOP or COMMAND INHIBIT when no accesses are
in progress. If power-down occurs when all banks are idle,
this mode is referred to as precharge power-down; if powerdown occurs when there is a row active in either bank, this
mode is referred to as active power-down. Entering powerdown deactivates the input and output buffers, excluding
CKE, for maximum power savings while in standby. The
device may not remain in the power-down state longer than
the refresh period (64ms) since no refresh operations are
performed in this mode.
The power-down state is exited by registering a NOP or
COMMAND INHIBIT and CKE HIGH at the desired clock
edge (meeting tCKS). See figure below.
A0-A9, A11
ALL BANKS
A10
BANK SELECT
BA0, BA1
BANK ADDRESS
POWER-DOWN
CLK
≥ tCKS
tCKS
CKE
COMMAND
NOP
All banks idle
NOP
Input buffers gated off
Enter power-down mode
Exit power-down mode
less than 64ms
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
ACTIVE
tRCD
tRAS
tRC
DON'T CARE
47
IS42S81600D,
IS42S16800D
POWER-DOWN MODE CYCLE
T0
T1
tCK
CLK
tCKS tCKH
T2
tCL
Tn+1
Tn+2
tCH
tCKS
tCKS
CKE
tCMS tCMH
COMMAND
PRECHARGE
NOP
NOP
NOP
ACTIVE
DQM/DQML
DQMH
ROW
A0-A9, A11
ALL BANKS
A10
ROW
SINGLE BANK
tAS tAH
BA0, BA1
BANK
BANK
DQ High-Z
Two clock cycles
Precharge all
active banks
48
All banks idle, enter
power-down mode
Input buffers gated
off while in
power-down mode
All banks idle
Exit power-down mode
DON'T CARE
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
IS42S81600D,
IS42S16800D
BURST READ/SINGLE WRITE
Four cases where CONCURRENT AUTO PRECHARGE
occurs are defined below.
The burst read/single write mode is entered by programming
the write burst mode bit (M9) in the mode register to a logic 1.
In this mode, all WRITE commands result in the access of a
single column location (burst of one), regardless of the
programmed burst length. READ commands access
columns according to the programmed burst length and
sequence, just as in the normal mode of operation (M9 = 0).
READ with Auto Precharge
1. Interrupted by a READ (with or without auto precharge):
A READ to bank m will interrupt a READ on bank n, CAS
latency later. The PRECHARGE to bank n will begin
when the READ to bank m is registered.
2. Interrupted by a WRITE (with or without auto precharge):
A WRITE to bank m will interrupt a READ on bank n when
registered. DQM should be used three clocks prior to the
WRITE command to prevent bus contention. The
PRECHARGE to bank n will begin when the WRITE to
bank m is registered.
CONCURRENT AUTO PRECHARGE
An access command (READ or WRITE) to another bank
while an access command with auto precharge enabled is
executing is not allowed by SDRAMs, unless the SDRAM
supports CONCURRENT AUTO PRECHARGE. ISSI
SDRAMs support CONCURRENT AUTO PRECHARGE.
READ With Auto Precharge interrupted by a READ
T0
T1
T2
T3
T4
T5
T6
T7
NOP
NOP
NOP
NOP
CLK
NOP
COMMAND
BANK n
READ - AP
BANK n
Page Active
READ - AP
BANK m
NOP
READ with Burst of 4
Interrupt Burst, Precharge
Idle
tRP - BANK n
Internal States
BANK m
Page Active
READ with Burst of 4
BANK n,
COL a
ADDRESS
tRP - BANK m
Precharge
BANK n,
COL b
DQ
DOUT a
DOUT a+1
DOUT b
DOUT b+1
CAS Latency - 3 (BANK n)
DON'T CARE
CAS Latency - 3 (BANK m)
READ With Auto Precharge interrupted by a WRITE
T0
T1
T2
T3
NOP
NOP
NOP
T4
T5
T6
T7
NOP
NOP
NOP
CLK
COMMAND
READ - AP
BANK n
BANK n
READ with Burst of 4
Internal States
Interrupt Burst, Precharge
Page Active
BANK m
ADDRESS
WRITE - AP
BANK m
tRP - BANK n
Page Active
WRITE with Burst of 4
BANK n,
COL a
Idle
tDPL - BANK m
Write-Back
BANK m,
COL b
DQM
DOUT a
DQ
DIN b
DIN b+1
DIN b+2
DIN b+3
CAS Latency - 3 (BANK n)
DON'T CARE
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Rev. E
07/28/08
49
IS42S81600D,
IS42S16800D
WRITE with Auto Precharge
4. Interrupted by a WRITE (with or without auto precharge):
AWRITE to bank m will interrupt a WRITE on bank n when
registered. The PRECHARGE to bank n will begin after
tDPL is met, where tDPL begins when the WRITE to bank m
is registered. The last valid data WRITE to bank n will be
data registered one clock prior to a WRITE to bank m.
3. Interrupted by a READ (with or without auto precharge):
A READ to bank m will interrupt a WRITE on bank n when
registered, with the data-out appearing (CAS latency) later.
The PRECHARGE to bank n will begin after tDPL is met,
where tDPL begins when the READ to bank m is registered.
The last valid WRITE to bank n will be data-in registered one
clock prior to the READ to bank m.
WRITE With Auto Precharge interrupted by a READ
T0
T1
T2
T3
T4
T5
T6
T7
NOP
NOP
NOP
NOP
CLK
NOP
COMMAND
BANK n
WRITE - AP
BANK n
Page Active
NOP
READ - AP
BANK m
WRITE with Burst of 4
Interrupt Burst, Write-Back
Precharge
tDPL - BANK n
tRP - BANK n
Internal States
BANK m
Page Active
READ with Burst of 4
BANK n,
COL a
ADDRESS
DQ
DIN a
tRP - BANK m
Precharge
BANK m,
COL b
DIN a+1
DOUT b
DOUT b+1
CAS Latency - 3 (BANK m)
DON'T CARE
WRITE With Auto Precharge interrupted by a WRITE
T0
T1
T2
T3
NOP
NOP
T4
T5
T6
T7
NOP
NOP
NOP
CLK
NOP
COMMAND
BANK n
WRITE - AP
BANK n
Page Active
WRITE with Burst of 4
WRITE - AP
BANK m
Interrupt Burst, Write-Back
tDPL - BANK n
Internal States
BANK m
ADDRESS
DQ
Page Active
WRITE with Burst of 4
BANK n,
COL a
DIN a
Precharge
tRP - BANK n
tDPL - BANK m
Write-Back
BANK m,
COL b
DIN a+1
DIN a+2
DIN b
DIN b+1
DIN b+2
DIN b+3
DON'T CARE
50
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
IS42S81600D,
IS42S16800D
SINGLE READ WITH AUTO PRECHARGE
T0
T1
tCK
CLK
T2
tCL
T3
T4
T5
T6
T7
NOP
NOP
T8
tCH
tCKS tCKH
CKE
tCMS tCMH
COMMAND
ACTIVE
NOP
NOP
NOP
READ
ACTIVE
NOP
tCMS tCMH
DQM/DQML
DQMH
tAS
tAH
A0-A9, A11
ROW
tAS tAH
A10
ROW
tAS tAH
BA0, BA1
BANK
COLUMN m(2)
ROW
ENABLE AUTO PRECHARGE
ROW
BANK
BANK
tOH
tAC
DOUT m
DQ
tHZ
tRCD
tRAS
DON'T CARE
CAS Latency
tRP
UNDEFINED
tRC
Notes:
1) CAS latency = 2, Burst Length = 1
2) X16: A9 and A11 = "Don't Care"
X8: A11 = "Don't Care"
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Rev. E
07/28/08
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IS42S81600D,
IS42S16800D
READ WITH AUTO PRECHARGE
T0
T1
T2
tCK
CLK
tCL
T3
T4
T5
T6
T7
T8
NOP
ACTIVE
tCH
tCKS tCKH
CKE
tCMS tCMH
COMMAND
ACTIVE
NOP
READ
NOP
NOP
NOP
NOP
tCMS tCMH
DQM/DQML
DQMH
tAS tAH
A0-A9, A11
ROW
tAS tAH
A10
ROW
tAS tAH
BA0, BA1
BANK
COLUMN m(2)
ROW
ENABLE AUTO PRECHARGE
ROW
BANK
BANK
tAC
DQ
tRCD
tRAS
tRC
tLZ
CAS Latency
tAC
DOUT m
tAC
DOUT m+1
tAC
DOUT m+2
tHZ
DOUT m+3
tOH
tOH
tOH
tOH
DON'T CARE
tRP
UNDEFINED
Notes:
1) CAS latency = 2, Burst Length = 4
2) X16: A9 and A11 = "Don't Care"
X8: A11 = "Don't Care"
52
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
IS42S81600D,
IS42S16800D
SINGLE READ WITHOUT AUTO PRECHARGE
T0
T1
T2
tCK
CLK
tCL
T3
T4
T5
T6
T7
T8
NOP
NOP
PRECHARGE
NOP
ACTIVE
NOP
tCH
tCKS tCKH
CKE
tCMS tCMH
COMMAND
ACTIVE
NOP
READ
tCMS tCMH
DQM/DQML
DQMH
tAS tAH
COLUMN m(2)
A0-A9, A11
ROW
tAS tAH
A10
ROW
tAS tAH
DISABLE AUTO PRECHARGE
SINGLE BANK
BANK
BANK
BANK
BA0, BA1
ROW
ALL BANKS
ROW
tAC
BANK
tOH
DOUT m
DQ
tRCD
tLZ
CAS Latency
tRAS
tHZ
DON'T CARE
tRP
UNDEFINED
tRC
Notes:
1) CAS latency = 2, Burst Length = 1
2) X16: A9 and A11 = "Don't Care"
X8: A11 = "Don't Care"
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
53
IS42S81600D,
IS42S16800D
READ WITHOUT AUTO PRECHARGE
T0
T1
T2
tCK
CLK
tCL
T3
T4
T5
T6
T7
T8
NOP
ACTIVE
tCH
tCKS tCKH
CKE
tCMS tCMH
COMMAND
ACTIVE
NOP
READ
NOP
NOP
NOP
PRECHARGE
tCMS tCMH
DQM/DQML
DQMH
tAS tAH
COLUMN m(2)
A0-A9, A11
ROW
tAS tAH
A10
ROW
tAS tAH
DISABLE AUTO PRECHARGE
SINGLE BANK
BANK
BANK
BANK
BA0, BA1
ROW
ALL BANKS
ROW
tAC
DQ
tRCD
tRAS
tRC
tLZ
CAS Latency
BANK
tAC
DOUT m
tAC
DOUT m+1
tAC
DOUT m+2
tHZ
DOUT m+3
tOH
tOH
tOH
tOH
DON'T CARE
tRP
UNDEFINED
Notes:
1) CAS latency = 2, Burst Length = 4
2) X16: A9 and A11 = "Don't Care"
X8: A11 = "Don't Care"
54
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
IS42S81600D,
IS42S16800D
SINGLE WRITE WITH AUTO PRECHARGE
T0
T1
T2
tCK
CLK
tCL
T3
T4
NOP
NOP
T5
T6
T7
T8
tCH
tCKS tCKH
CKE
tCMS tCMH
COMMAND
ACTIVE
NOP
WRITE
PRECHARGE
NOP
ACTIVE
NOP
tCMS tCMH
DQM/DQML
DQMH
tAS tAH
A0-A9, A11
ROW
tAS tAH
A10
ROW
tAS tAH
BA0, BA1
COLUMN m(2)
ROW
DISABLE AUTO PRECHARGE
ALL BANKS
ROW
SINGLE BANK
BANK
BANK
BANK
BANK
tDS tDH
DQ
DIN m
tRCD
tRAS
tRC
tDPL(3)
tRP
DON'T CARE
Notes:
1) Burst Length = 1
2) X16: A9 and A11 = "Don't Care"
X8: A11 = "Don't Care"
3) tRAS must not be violated.
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
55
IS42S81600D,
IS42S16800D
SINGLE WRITE - WITHOUT AUTO PRECHARGE
T0
T1
T2
tCK
CLK
tCL
T3
T4
NOP
NOP
T5
T6
T7
T8
tCH
tCKS tCKH
CKE
tCMS tCMH
COMMAND
ACTIVE
NOP
WRITE
PRECHARGE
NOP
ACTIVE
NOP
tCMS tCMH
DQM/DQML
DQMH
tAS tAH
A0-A9, A11
ROW
tAS tAH
A10
ROW
tAS tAH
BA0, BA1
COLUMN m(2)
ROW
DISABLE AUTO PRECHARGE
ALL BANKS
ROW
SINGLE BANK
BANK
BANK
BANK
BANK
tDS tDH
DQ
DIN m
tRCD
tRAS
tRC
tDPL(3)
tRP
DON'T CARE
Notes:
1) Burst Length = 1
2) X16: A9 and A11 = "Don't Care"
X8: A11 = "Don't Care"
3) tRAS must not be violated.
56
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
IS42S81600D,
IS42S16800D
WRITE - WITHOUT AUTO PRECHARGE
T0
T1
tCK
CLK
T2
tCL
T3
T4
T5
T6
NOP
NOP
NOP
T7
T8
tCH
tCKS tCKH
CKE
tCMS tCMH
COMMAND
ACTIVE
NOP
WRITE
PRECHARGE
NOP
ACTIVE
tCMS tCMH
DQM/DQML
DQMH
tAS tAH
A0-A9, A11
ROW
tAS tAH
A10
ROW
tAS tAH
BA0, BA1
COLUMN m(2)
ROW
ALL BANKS
ROW
SINGLE BANK
DISABLE AUTO PRECHARGE
BANK
BANK
tDS tDH
DQ
DIN m
BANK
tDS tDH
DIN m+1
tRCD
tRAS
tRC
tDS tDH
DIN m+2
tDS
BANK
tDH
DIN m+3
tDPL(3)
tRP
DON'T CARE
Notes:
1) Burst Length = 4
2) X16: A9 and A11 = "Don't Care"
X8: A11 = "Don't Care"
3) tRAS must not be violated.
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
57
IS42S81600D,
IS42S16800D
WRITE - WITH AUTO PRECHARGE
T0
T1
tCK
CLK
T2
tCL
T3
T4
T5
T6
T7
T8
T9
NOP
NOP
NOP
NOP
NOP
NOP
ACTIVE
tCH
tCKS tCKH
CKE
tCMS tCMH
COMMAND
ACTIVE
NOP
WRITE
tCMS tCMH
DQM/DQML
DQMH
tAS tAH
A0-A9, A11
ROW
tAS tAH
A10
ROW
tAS tAH
BA0, BA1
BANK
COLUMN m(2)
ROW
ENABLE AUTO PRECHARGE
ROW
BANK
tDS
DQ
tDH
DIN m
tRCD
tRAS
tRC
BANK
tDS tDH
DIN m+1
tDS tDH
DIN m+2
tDS
tDH
DIN m+3
tDPL
tRP
DON'T CARE
Notes:
1) Burst Length = 4
2) X16: A9 and A11 = "Don't Care"
X8: A11 = "Don't Care"
58
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
IS42S81600D,
IS42S16800D
ORDERING INFORMATION - VDD = 3.3V
Commercial Range: 0°°C to 70°°C
Frequency
Speed (ns)
Order Part No.
166 MHz
6
IS42S81600D-6T
54-Pin TSOPII
143 MHz
7
IS42S81600D-7T
54-Pin TSOPII
Frequency
Speed (ns)
166 MHz
6
IS42S16800D-6T
54-Pin TSOPII
166 MHz
6
IS42S16800D-6B
54-ball BGA
143 MHz
7
IS42S16800D-7T
54-Pin TSOPII
143 MHz
7
IS42S16800D-7B
54-ball BGA
Order Part No.
Package
Package
ORDERING INFORMATION - VDD = 3.3V
Industrial Range: -40°°C to 85°°C
Frequency
Speed (ns)
Order Part No.
143 MHz
7
Frequency
Speed (ns)
143 MHz
7
IS42S16800D-7TI
54-Pin TSOPII
143 MHz
7
IS42S16800D-7BI
54-ball BGA
IS42S81600D-7TI
Order Part No.
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
Package
54-Pin TSOPII
Package
59
IS42S81600D,
IS42S16800D
ORDERING INFORMATION - VDD = 3.3V
Commercial Range: 0°°C to 70°°C
Frequency
Speed (ns)
Order Part No.
Package
166 MHz
6
IS42S81600D-6TL
54-Pin TSOPII, Lead-free
143 MHz
7
IS42S81600D-7TL
54-Pin TSOPII, Lead-free
Frequency
Speed (ns)
Order Part No.
Package
166 MHz
6
IS42S16800D-6TL
54-Pin TSOPII, Lead-free
166 MHz
6
IS42S16800D-6BL
54-ball BGA, Lead-free
143 MHz
7
IS42S16800D-7TL
54-Pin TSOPII, Lead-free
143 MHz
7
IC42S16800D-7TL
54-Pin TSOPII, Lead-free
143 MHz
7
IS42S16800D-7BL
54-ball BGA, Lead-free
133 MHz
7.5
IS42S16800D-75ETL
54-Pin TSOPII, Lead-free
133 MHz
7.5
IS42S16800D-75EBL 54-ball BGA, Lead-free
ORDERING INFORMATION - VDD = 3.3V
Industrial Range: -40°°C to 85°°C
Frequency
Speed (ns)
143 MHz
7
Frequency
Speed (ns)
166 MHz
Order Part No.
Package
IS42S81600D-7TLI
54-Pin TSOPII, Lead-free
Order Part No.
Package
6
IS42S16800D-6TLI
54-Pin TSOPII, Lead-free
143 MHz
7
IS42S16800D-7TLI
54-Pin TSOPII, Lead-free
143 MHz
7
IS42S16800D-7BLI
54-ball BGA, Lead-free
133 MHz
7.5
IS42S16800D-75ETLI 54-Pin TSOPII, Lead-free
133 MHz
7.5
IS42S16800D-75EBLI 54-ball BGA, Lead-free
60
Integrated Silicon Solution, Inc. — www.issi.com
Rev. E
07/28/08
PACKAGING INFORMATION
Mini Ball Grid Array
Package Code: B (54-Ball)
ø 0.45 +/−0.05 (54X)
1 2 3 4 5 6 7 8 9
9 8 7 6 5 4 3 2 1
A
B
C
D
E
F
G
H
J
A
B
C
D
E
F
G
H
J
e
D
D1
e
A1
E1
E
A
SEATING PLANE
Notes:
1. Controlling dimensions are in millimeters.
2. 0.8 mm Ball Pitch
mBGA - 8mm x 13mm
MILLIMETERS
Sym. Min.
N0.
Leads
Typ. Max.
Min. Typ.
Max.
54
A
—
—
1.00
A1
0.30
0.35
0.40
D
12.90
D1
INCHES
13.00 13.10
—
—
0.039
0.012 0.014 0.016
0.508 0.512
—
0.252
0.516
—
6.40
—
E
7.90
8.00
8.10
E1
—
6.40
—
—
0.252
—
e
—
0.80
—
—
0.031
—
0.311 0.315
—
0.319
Copyright © 2006 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. — www.issi.com — 1-800-379-4774
Rev. B
03/28/06
PACKAGING INFORMATION
Plastic TSOP 54–Pin, 86-Pin
Package Code: T (Type II)
N
N/2+1
Notes:
1. Controlling dimension: millimieters,
unless otherwise specified.
2. BSC = Basic lead spacing between
centers.
3. Dimensions D and E1 do not include
mold flash protrusions and should be
E
E1
measured from the bottom of the
package.
4. Formed leads shall be planar with
respect to one another within 0.004
inches at the seating plane.
N/2
1
D
SEATING PLANE
A
ZD
b
e
Plastic TSOP (T - Type II)
Millimeters
Inches
Min
Max
Min
Max
Symbol
Ref. Std.
No. Leads (N)
A
A1
A2
b
C
D
E1
E
e
L
L1
ZD
α
54
—
1.20
0.05 0.15
—
—
0.30 0.45
0.12 0.21
22.02 22.42
10.03 10.29
11.56 11.96
0.80 BSC
0.40 0.60
—
—
0.71 REF
0°
8°
Integrated Silicon Solution, Inc.
Rev. D
03/13/07
—
0.047
0.002 0.006
—
—
0.012 0.018
0.005 0.0083
0.867 0.8827
0.395 0.405
0.455 0.471
0.031 BSC
0.016 0.024
—
—
0°
8°
L
α
A1
C
Plastic TSOP (T - Type II)
Millimeters
Inches
Symbol Min Max
Min
Max
Ref. Std.
No. Leads (N)
86
A
A1
A2
b
C
D
E1
E
e
L
L1
ZD
α
—
1.20
0.05 0.15
0.95 1.05
0.17 0.27
0.12 0.21
22.02 22.42
10.03 10.29
11.56 11.96
0.50 BSC
0.40 0.60
0.80 REF
0.61 REF
0°
8°
—
0.047
0.002 0.006
0.037 0.041
0.007 0.011
0.005 0.008
0.867 0.8827
0.395 0.405
0.455 0.471
0.020 BSC
0.016 0.024
0.031 REF
0.024 BSC
0°
8°
1