Figure 20. Block Diagram of 32,768 x 9 and" />
參數(shù)資料
型號(hào): IDT72271LA15TFI
廠商: IDT, Integrated Device Technology Inc
文件頁數(shù): 18/27頁
文件大?。?/td> 0K
描述: IC FIFO 16384X18 LP 15NS 64QFP
標(biāo)準(zhǔn)包裝: 80
系列: 7200
功能: 同步
存儲(chǔ)容量: 288K(16K x 18)
數(shù)據(jù)速率: 67MHz
訪問時(shí)間: 15ns
電源電壓: 4.5 V ~ 5.5 V
工作溫度: -40°C ~ 85°C
安裝類型: 表面貼裝
封裝/外殼: 64-LQFP
供應(yīng)商設(shè)備封裝: 64-TQFP(10x10)
包裝: 托盤
其它名稱: 72271LA15TFI
25
COMMERCIALANDINDUSTRIAL
TEMPERATURERANGES
IDT72261LA/72271LA SuperSync FIFO
16,384 x 9 and 32,768 x 9
Figure 20. Block Diagram of 32,768 x 9 and 65,536 x 9 Depth Expansion
DEPTH EXPANSION CONFIGURATION (FWFT MODE ONLY)
The IDT72261LA can easily be adapted to applications requiring depths
greater than 16,384 and 32,768 for the IDT72271LA with a 9-bit bus width.
InFWFTmode,theFIFOscanbeconnectedinseries(thedataoutputsofone
FIFOconnectedtothedatainputsofthenext)withnoexternallogicnecessary.
Theresultingconfigurationprovidesatotaldepthequivalenttothesumofthe
depthsassociatedwitheachsingleFIFO. Figure22showsadepthexpansion
using two IDT72261LA/72271LA devices.
Care should be taken to select FWFT mode during Master Reset for all
FIFOsinthedepthexpansionconfiguration. Thefirstwordwrittentoanempty
configurationwillpassfromoneFIFOtothenext("rippledown")untilitfinally
appears at the outputs of the last FIFO in the chain–no read operation is
necessary but the RCLK of each FIFO must be free-running. Each time the
datawordappearsattheoutputsofoneFIFO,thatdevice'sORlinegoesLOW,
enabling a write to the next FIFO in line.
Foranemptyexpansionconfiguration,theamountoftimeittakesforORof
thelastFIFOinthechaintogoLOW(i.e.validdatatoappearonthelastFIFO's
outputs)afterawordhasbeenwrittentothefirstFIFOisthesumofthedelays
for each individual FIFO:
(N – 1)*(4*transfer clock) + 3*TRCLK
where N is the number of FIFOs in the expansion and TRCLK is the RCLK
period. NotethatextracyclesshouldbeaddedforthepossibilitythatthetSKEW3
Dn
INPUT READY
WRITE ENABLE
WRITE CLOCK
WEN
WCLK
IR
DATA IN
RCLK
READ CLOCK
RCLK
REN
OE
OUTPUT ENABLE
OUTPUT READY
Qn
Dn
IR
GND
WEN
WCLK
OR
REN
OE
Qn
READ ENABLE
OR
DATA OUT
IDT
72261LA
72271LA
TRANSFER CLOCK
4671 drw 23
n
FWFT/SI
IDT
72261LA
72271LA
specificationisnotmetbetweenWCLKandtransferclock,orRCLKandtransfer
clock, for the OR flag.
The "ripple down" delay is only noticeable for the first word written to an
empty depth expansion configuration. There will be no delay evident for
subsequentwordswrittentotheconfiguration.
The first free location created by reading from a full depth expansion
configurationwill"bubbleup"fromthelastFIFOtothepreviousoneuntilitfinally
moves into the first FIFO of the chain. Each time a free location is created in
one FIFO of the chain, that FIFO's IRlinegoesLOW,enablingthepreceding
FIFO to write a word to fill it.
Forafullexpansionconfiguration,theamountoftimeittakesforIRofthefirst
FIFO in the chain to go LOW after a word has been read from the last FIFO
is the sum of the delays for each individual FIFO:
(N – 1)*(3*transfer clock) + 2 TWCLK
where N is the number of FIFOs in the expansion and TWCLK is the WCLK
period. Note that extra cycles should be added for the possibility that the
tSKEW1 specification is not met between RCLK and transfer clock, or WCLK
and transfer clock, for the IR flag.
The Transfer Clock line should be tied to either WCLK or RCLK,
whichever is faster. Both these actions result in data moving, as quickly
as possible, to the end of the chain and free locations to the beginning of
the chain.
相關(guān)PDF資料
PDF描述
MS27513E22A55S CONN RCPT 55POS BOX MNT W/SCKT
V72B28M250BG CONVERTER MOD DC/DC 28V 250W
MS27484E8A98SD CONN PLUG 3POS STRAIGHT W/SCKT
MAX1031BCEG+T IC ADC 10BIT 300KSPS 24-QSOP
V72B28M250BF3 CONVERTER MOD DC/DC 28V 250W
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
IDT72271LA15TFI8 功能描述:IC FIFO 16384X18 LP 15NS 64QFP RoHS:否 類別:集成電路 (IC) >> 邏輯 - FIFO 系列:7200 標(biāo)準(zhǔn)包裝:90 系列:7200 功能:同步 存儲(chǔ)容量:288K(16K x 18) 數(shù)據(jù)速率:100MHz 訪問時(shí)間:10ns 電源電壓:4.5 V ~ 5.5 V 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:64-LQFP 供應(yīng)商設(shè)備封裝:64-TQFP(14x14) 包裝:托盤 其它名稱:72271LA10PF
IDT72271LA20PF 功能描述:IC FIFO 16384X18 LP 20NS 64QFP RoHS:否 類別:集成電路 (IC) >> 邏輯 - FIFO 系列:7200 標(biāo)準(zhǔn)包裝:90 系列:7200 功能:同步 存儲(chǔ)容量:288K(16K x 18) 數(shù)據(jù)速率:100MHz 訪問時(shí)間:10ns 電源電壓:4.5 V ~ 5.5 V 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:64-LQFP 供應(yīng)商設(shè)備封裝:64-TQFP(14x14) 包裝:托盤 其它名稱:72271LA10PF
IDT72271LA20PF8 功能描述:IC FIFO 16384X18 LP 20NS 64QFP RoHS:否 類別:集成電路 (IC) >> 邏輯 - FIFO 系列:7200 標(biāo)準(zhǔn)包裝:90 系列:7200 功能:同步 存儲(chǔ)容量:288K(16K x 18) 數(shù)據(jù)速率:100MHz 訪問時(shí)間:10ns 電源電壓:4.5 V ~ 5.5 V 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:64-LQFP 供應(yīng)商設(shè)備封裝:64-TQFP(14x14) 包裝:托盤 其它名稱:72271LA10PF
IDT72271LA20PFI 功能描述:IC FIFO 16384X18 LP 20NS 64QFP RoHS:否 類別:集成電路 (IC) >> 邏輯 - FIFO 系列:7200 標(biāo)準(zhǔn)包裝:90 系列:7200 功能:同步 存儲(chǔ)容量:288K(16K x 18) 數(shù)據(jù)速率:100MHz 訪問時(shí)間:10ns 電源電壓:4.5 V ~ 5.5 V 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:64-LQFP 供應(yīng)商設(shè)備封裝:64-TQFP(14x14) 包裝:托盤 其它名稱:72271LA10PF
IDT72271LA20PFI8 功能描述:IC FIFO 16384X18 LP 20NS 64QFP RoHS:否 類別:集成電路 (IC) >> 邏輯 - FIFO 系列:7200 標(biāo)準(zhǔn)包裝:90 系列:7200 功能:同步 存儲(chǔ)容量:288K(16K x 18) 數(shù)據(jù)速率:100MHz 訪問時(shí)間:10ns 電源電壓:4.5 V ~ 5.5 V 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:64-LQFP 供應(yīng)商設(shè)備封裝:64-TQFP(14x14) 包裝:托盤 其它名稱:72271LA10PF