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參數(shù)資料
| 型號： | IDT71P71804 |
| 廠商： | Integrated Device Technology, Inc. |
| 英文描述： | 18Mb Pipelined DDR⑩II SRAM Burst of 2 |
| 中文描述： | 35.7流水線的DDR II SRAM的突發(fā)⑩2 |
| 文件頁數(shù)： | 2/23頁 |
| 文件大?。?/td> | 241K |
| 代理商： | IDT71P71804 |
6.42
IDT71P71804 (1M x 18-Bit) 71P71604 (512K x 36-Bit)
18 Mb DDR II SRAM Burst of 2 Commercial Temperature Range
Write operations are initiated by holding the Read/Write control input
(R/
W
) low the load control input (
LD
) low and presenting the write
address to the address port during the rising edge of K, which will latch
the address.
On the following rising edge of K, the first word of the two
word burst must be present on the data input bus DQ[x:O], along with the
appropriate byte write (
BWx
) inputs. On the following rising edge of
K
,
the second half of the data write burst will be accepted at the device input
with the designated (
BWx
) inputs.
DDRII devices internally store two words of the burst as a single,
wide word and will retain their order in the burst. The x18 and x36 DDRll
devices have the ability to address to the individual word level using the
SA0 address, but the burst will continue in a linear sequence and wraps
around without incrementing the SA bits. Simlarly when reading x18 and
x36 DDRll devices, the read burst will begin at the designated address,
but if the burst is started at any other position than the first word of the
burst, the burst will wrap back on itself and read the first locations before
completing. The x18 and x36 DDR II devices can also use the byte write
signals to prevent writing any individual bytes or word of the burst.
Output Enables
The DDRII SRAMautomatically enables and disables the DQ[X:0]
outputs. When a valid read is in progress, and data is present at the
output, the output will be enabled. If no valid data is present at the output
(read not active), the output will be disabled (high impedance). The
echo clocks will remain valid at all times and cannot be disabled or turned
off. During power-up the DQ outputs will come up in a high impedance
state.
Programmable Impedance
An external resistor, RQ, must be connected between the ZQ pin
on the SRAMand Vss to allow the SRAMto adjust its output drive
impedance. The value of RQ must be 5X the value of the intended drive
impedance of the SRAM. The allowable range of RQ to guarantee
impedance matching with a tolerance of +/- 10% is between 175 ohms
and 350 ohms, with V
DDQ
= 1.5V. The output impedance is adjusted
every 1024 clock cycles to correct for drifts in supply voltage and tem-
perature. If the user wishes to drive the output impedance of the SRAM
to it’s lowest value, the ZQ pin may be tied to V
DDQ
.
The K and
K
clocks are the primary device input clocks. The K clock
is used to clock in the control signals (
LD
, R/
W
and
BW
x), the address,
and the first word of the data burst during a write operation. The
K
clock
BW
x), and the second word of the
data burst during a write operation. The K and
K
clocks are also used
internally by the SRAM In the event that the user disables the C and
clocks, the K and
clocks will also be used to clock the data out of the
output register and generate the echo clocks.
The C and
C
clocks may be used to clock the data out of the output
register during read operations and to generate the echo clocks. C and
C
must be presented to the SRAMwithin the timng tolerances. The
output data fromthe DDRII will be closely aligned to the C and
C
input,
through the use of an internal DLL. When C is presented to the DDRII
SRAM the DLL will have already internally clocked the first data word to
arrive at the device output simultaneously with the arrival of the
C
clock.
The C and second data word of the burst will also correspond.
Single Clock Mode
The DDRII SRAMmay be operated with a single clock pair. C and
C
may be disabled by tying both signals high, forcing the outputs and echo
clocks to be controlled instead by the K and
K
clocks.
DLL Operation
The DLL in the output structure of the DDRII SRAMcan be used to
closely align the incomng clocks C and
C
with the output of the data,
generating very tight tolerances between the two. The user may disable
the DLL by holding
Doff
low With the DLL off, the C and
C
(or K and
if C and
are not used) will directly clock the output register of the SRAM
With the DLL off, there will be a propagation delay fromthe time the clock
enters the device until the data appears at the output.
Echo Clock
The echo clocks, CQ and
CQ
, are generated by the C and
C
clocks
(or K,
if C,
C
are disabled). The rising edge of C generates the rising
edge of CQ, and the falling edge of
CQ
. The rising edge of
C
generates
the rising edge of
CQ
and the falling edge of CQ. This scheme improves
the correlation of the rising and falling edges of the echo clock and will
improve the duty cycle of the individual signals.
The echo clock is very closely aligned with the data, guaranteeing
that the echo clock will remain closely correlated with the data, within the
tolerances designated.
Read and Write Operations
Read operations are initiated by holding Read/Write control input
(R/
W
) high, the load control input (
LD
) low and presenting the read
address to the address port during the rising edge of K, which will latch
the address. The data will then be read and will appear at the device
output at the designated time in correspondence with the C and
C
clocks.
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| IDT71P71804S167BQ | 功能描述:IC SRAM 18MBIT 167MHZ 165FBGA RoHS:否 類別:集成電路 (IC) >> 存儲器 系列:- 產(chǎn)品變化通告:Product Discontinuation 26/Apr/2010 標準包裝:136 系列:- 格式 - 存儲器:RAM 存儲器類型:SRAM - 同步，DDR II 存儲容量:18M（1M x 18） 速度:200MHz 接口:并聯(lián) 電源電壓:1.7 V ~ 1.9 V 工作溫度:0°C ~ 70°C 封裝/外殼:165-TBGA 供應(yīng)商設(shè)備封裝:165-CABGA（13x15） 包裝:托盤 其它名稱:71P71804S200BQ |
| IDT71P71804S167BQ8 | 功能描述:IC SRAM 18MBIT 167MHZ 165FBGA RoHS:否 類別:集成電路 (IC) >> 存儲器 系列:- 產(chǎn)品變化通告:Product Discontinuation 26/Apr/2010 標準包裝:136 系列:- 格式 - 存儲器:RAM 存儲器類型:SRAM - 同步，DDR II 存儲容量:18M（1M x 18） 速度:200MHz 接口:并聯(lián) 電源電壓:1.7 V ~ 1.9 V 工作溫度:0°C ~ 70°C 封裝/外殼:165-TBGA 供應(yīng)商設(shè)備封裝:165-CABGA（13x15） 包裝:托盤 其它名稱:71P71804S200BQ |
| IDT71P71804S167BQG | 功能描述:IC SRAM 18MBIT 167MHZ 165FBGA RoHS:是 類別:集成電路 (IC) >> 存儲器 系列:- 產(chǎn)品變化通告:Product Discontinuation 26/Apr/2010 標準包裝:136 系列:- 格式 - 存儲器:RAM 存儲器類型:SRAM - 同步，DDR II 存儲容量:18M（1M x 18） 速度:200MHz 接口:并聯(lián) 電源電壓:1.7 V ~ 1.9 V 工作溫度:0°C ~ 70°C 封裝/外殼:165-TBGA 供應(yīng)商設(shè)備封裝:165-CABGA（13x15） 包裝:托盤 其它名稱:71P71804S200BQ |
| IDT71P71804S200BQ | 功能描述:IC SRAM 18MBIT 200MHZ 165FBGA RoHS:否 類別:集成電路 (IC) >> 存儲器 系列:- 產(chǎn)品變化通告:Product Discontinuation 26/Apr/2010 標準包裝:136 系列:- 格式 - 存儲器:RAM 存儲器類型:SRAM - 同步，DDR II 存儲容量:18M（1M x 18） 速度:200MHz 接口:并聯(lián) 電源電壓:1.7 V ~ 1.9 V 工作溫度:0°C ~ 70°C 封裝/外殼:165-TBGA 供應(yīng)商設(shè)備封裝:165-CABGA（13x15） 包裝:托盤 其它名稱:71P71804S200BQ |
| IDT71P71804S200BQ8 | 功能描述:IC SRAM 18MBIT 200MHZ 165FBGA RoHS:否 類別:集成電路 (IC) >> 存儲器 系列:- 標準包裝:378 系列:- 格式 - 存儲器:閃存 存儲器類型:FLASH 存儲容量:8M（1M x 8，512K x 16） 速度:110ns 接口:并聯(lián) 電源電壓:2.7 V ~ 3.6 V 工作溫度:-40°C ~ 85°C 封裝/外殼:48-CBGA 供應(yīng)商設(shè)備封裝:48-CBGA（7x7） 包裝:托盤 |
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