參數(shù)資料
型號: ICS843246AMIT
元件分類: 時(shí)鐘產(chǎn)生/分配
英文描述: 333.33 MHz, OTHER CLOCK GENERATOR, PDSO24
封裝: 7.50 X 15.33 MM, 2.30 MM HEIGHT, MS-013, MO-119, SOIC-24
文件頁數(shù): 15/15頁
文件大小: 215K
代理商: ICS843246AMIT
843246AMI
www.icst.com/products/hiperclocks.html
REV. A JUNE 16, 2006
9
Integrated
Circuit
Systems, Inc.
ICS843246I
FEMTOCLOCKS CRYSTAL-TO-3.3V LVPECL
FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER
PRELIMINARY
TERMINATION FOR 3.3V LVPECL OUTPUT
V
CC - 2V
50
50
RTT
Z
o = 50
Z
o = 50
FOUT
FIN
RTT =
Z
o
1
((V
OH + VOL) / (VCC – 2)) – 2
3.3V
125
125
84
84
Z
o = 50
Z
o = 50
FOUT
FIN
The clock layout topology shown below is a typical termi-
nation for LVPECL outputs. The two different layouts men-
tioned are recommended only as guidelines.
FOUT and nFOUT are low impedance follower outputs that
generate ECL/LVPECL compatible outputs. Therefore, termi-
nating resistors (DC current path to ground) or current
sources must be used for functionality. These outputs are
FIGURE 3B. LVPECL OUTPUT TERMINATION
FIGURE 3A. LVPECL OUTPUT TERMINATION
designed to drive 50
transmission lines. Matched imped-
ance techniques should be used to maximize operating
frequency and minimize signal distortion.
Figures 3A and
3B show two different layouts which are recommended only
as guidelines. Other suitable clock layouts may exist and it
would be recommended that the board designers simulate to
guarantee compatibility across all printed circuit and clock
component process variations.
INPUTS:
LVCMOS CONTROL PINS:
All control pins have internal pull-ups or pull-downs; additional
resistance is not required but can be added for additional
protection. A 1k
resistor can be used.
RECOMMENDATIONS FOR UNUSED INPUT AND OUTPUT PINS
OUTPUTS:
LVPECL OUTPUT
All unused LVPECL outputs can be left floating. We
recommend that there is no trace attached. Both sides of the
differential output pair should either be left floating or
terminated.
相關(guān)PDF資料
PDF描述
ICS843246AMLFT 333.33 MHz, OTHER CLOCK GENERATOR, PDSO24
ICS843246AGT 333.33 MHz, OTHER CLOCK GENERATOR, PDSO24
ICS843246AMLF 333.33 MHz, OTHER CLOCK GENERATOR, PDSO24
ICS84324AMLFT 125 MHz, OTHER CLOCK GENERATOR, PDSO24
ICS84324DM 125 MHz, OTHER CLOCK GENERATOR, PDSO24
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
ICS843246AMLF 制造商:ICS 制造商全稱:ICS 功能描述:FEMTOCLOCKS⑩ CRYSTAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER
ICS843246AMLFT 制造商:ICS 制造商全稱:ICS 功能描述:FEMTOCLOCKS⑩ CRYSTAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER
ICS843246AMT 制造商:ICS 制造商全稱:ICS 功能描述:FEMTOCLOCKS⑩ CRYSTAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER
ICS843246BGI 制造商:IDT 制造商全稱:Integrated Device Technology 功能描述:FEMTOCLOCKS⑩ CRYSTAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER
ICS843246BGILF 制造商:IDT 制造商全稱:Integrated Device Technology 功能描述:FEMTOCLOCKS⑩ CRYSTAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER