參數(shù)資料
型號: ICS345RLF
英文描述: Triple PLL Field Programmable SS VersaClock Synthesizer
中文描述: 三現(xiàn)場可編程鎖相環(huán)頻率合成器不銹鋼VersaClock
文件頁數(shù): 3/7頁
文件大?。?/td> 153K
代理商: ICS345RLF
Triple PLL Field Programmable SS VersaClock Synthesizer
MDS 345 D
3
Revision 090704
Integrated Circuit Systems, Inc.
525 Race Street, San Jose, CA 95126
tel (408) 297-1201
www.icst.com
ICS345
External Components
Series Termination Resistor
Clock output traces over one inch should use series
termination. To series terminate a 50
trace (a
commonly used trace impedance), place a 33
resistor
in series with the clock line, as close to the clock output
pin as possible. The nominal impedance of the clock
output is 20
.
Decoupling Capacitors
As with any high-performance mixed-signal IC, the
ICS345 must be isolated from system power supply
noise to perform optimally.
Decoupling capacitors of 0.01μF must be connected
between each VDD and the PCB ground plane.
Crystal Load Capacitors
The device crystal connections should include pads for
small capacitors from X1 to ground and from X2 to
ground. These capacitors are used to adjust the stray
capacitance of the board to match the nominally
required crystal load capacitance. Because load
capacitance can only be increased in this trimming
process, it is important to keep stray capacitance to a
minimum by using very short PCB traces (and no vias)
been the crystal and device. Crystal capacitors must be
connected from each of the pins X1 and X2 to ground.
The value (in pF) of these crystal caps should equal
(C
L
-6 pF)*2. In this equation, C
L
= crystal load
capacitance in pF. Example: For a crystal with a 16 pF
load capacitance, each crystal capacitor would be 20
pF [(16-6) x 2] = 20.
PCB Layout Recommendations
For optimum device performance and lowest output
phase noise, the following guidelines should be
observed.
1) Each 0.01μF decoupling capacitor should be
mounted on the component side of the board as close
to the VDD pin as possible. No vias should be used
between decoupling capacitor and VDD pin. The PCB
trace to VDD pin should be kept as short as possible,
as should the PCB trace to the ground via.
2) The external crystal should be mounted just next to
the device with short traces. The X1 and X2 traces
should not be routed next to each other with minimum
spaces, instead they should be separated and away
from other traces.
3) To minimize EMI, the 33
series termination resistor
(if needed) should be placed close to the clock output.
4) An optimum layout is one with all components on the
same side of the board, minimizing vias through other
signal layers.
ICS345 Configuration Capabilities
The architecture of the ICS345 allows the user to easily
configure the device to a wide range of output
frequencies, for a given input reference frequency.
The frequency multiplier PLL provides a high degree of
precision. The M/N values (the multiplier/divide values
available to generate the target VCO frequency) can be
set within the range of M = 1 to 2048 and N = 1 to 1024.
The ICS345 also provides separate output divide
values, from 2 through 20, to allow the two output clock
banks to support widely differing frequency values from
the same PLL.
Each output frequency can be represented as:
OutputDivide
=
ICS VersaClock Software
ICS applies years of PLL optimization experience into a
user friendly software that accepts the user’s target
reference clock and output frequencies and generates
the lowest jitter, lowest power configuration, with only a
press of a button. The user does not need to have prior
PLL experience or determine the optimal VCO
frequency to support multiple output frequencies.
VersaClock software quickly evaluates accessible VCO
frequencies with available output divide values and
provides an easy to understand, bar code rating for the
target output frequencies. The user may evaluate
output accuracy, performance trade-off scenarios in
seconds.
Spread Spectrum Modulation
The ICS345 utilizes frequency modulation (FM) to
distribute energy over a range of frequencies. By
modulating the output clock frequencies, the device
effectively lowers energy across a broader range of
OutputFreq
------REFFreq
N
M
相關(guān)PDF資料
PDF描述
ICS345RP Triple PLL Field Programmable SS VersaClock Synthesizer
ICS3726-02 HIGH PERFORMANCE VCXO
ICS3726M-02 HIGH PERFORMANCE VCXO
ICS3726M-02LF HIGH PERFORMANCE VCXO
ICS3726M-02LFT HIGH PERFORMANCE VCXO
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
ICS345RP 功能描述:IC VERSACLOCK SYNTHESIZER 20QSOP RoHS:否 類別:集成電路 (IC) >> 時鐘/計時 - 時鐘發(fā)生器,PLL,頻率合成器 系列:VersaClock™ 產(chǎn)品變化通告:Product Discontinuation 04/May/2011 標準包裝:96 系列:- 類型:時鐘倍頻器,零延遲緩沖器 PLL:帶旁路 輸入:LVTTL 輸出:LVTTL 電路數(shù):1 比率 - 輸入:輸出:1:8 差分 - 輸入:輸出:無/無 頻率 - 最大:133.3MHz 除法器/乘法器:是/無 電源電壓:3 V ~ 3.6 V 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:16-TSSOP(0.173",4.40mm 寬) 供應商設備封裝:16-TSSOP 包裝:管件 其它名稱:23S08-5HPGG
ICS345RPLF 功能描述:IC VERSACLOCK SYNTHESIZER 20QSOP RoHS:是 類別:集成電路 (IC) >> 時鐘/計時 - 時鐘發(fā)生器,PLL,頻率合成器 系列:VersaClock™ 標準包裝:2,000 系列:- 類型:PLL 頻率合成器 PLL:是 輸入:晶體 輸出:時鐘 電路數(shù):1 比率 - 輸入:輸出:1:1 差分 - 輸入:輸出:無/無 頻率 - 最大:1GHz 除法器/乘法器:是/無 電源電壓:4.5 V ~ 5.5 V 工作溫度:-20°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:16-LSSOP(0.175",4.40mm 寬) 供應商設備封裝:16-SSOP 包裝:帶卷 (TR) 其它名稱:NJW1504V-TE1-NDNJW1504V-TE1TR
ICS345RPLFT 功能描述:IC VERSACLOCK SYNTHESIZER 20QSOP RoHS:是 類別:集成電路 (IC) >> 時鐘/計時 - 時鐘發(fā)生器,PLL,頻率合成器 系列:VersaClock™ 標準包裝:2,000 系列:- 類型:PLL 時鐘發(fā)生器 PLL:帶旁路 輸入:LVCMOS,LVPECL 輸出:LVCMOS 電路數(shù):1 比率 - 輸入:輸出:2:11 差分 - 輸入:輸出:是/無 頻率 - 最大:240MHz 除法器/乘法器:是/無 電源電壓:3.135 V ~ 3.465 V 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:32-LQFP 供應商設備封裝:32-TQFP(7x7) 包裝:帶卷 (TR)
ICS345RPT 功能描述:IC VERSACLOCK SYNTHESIZER 20QSOP RoHS:否 類別:集成電路 (IC) >> 時鐘/計時 - 時鐘發(fā)生器,PLL,頻率合成器 系列:VersaClock™ 產(chǎn)品變化通告:Product Discontinuation 04/May/2011 標準包裝:96 系列:- 類型:時鐘倍頻器,零延遲緩沖器 PLL:帶旁路 輸入:LVTTL 輸出:LVTTL 電路數(shù):1 比率 - 輸入:輸出:1:8 差分 - 輸入:輸出:無/無 頻率 - 最大:133.3MHz 除法器/乘法器:是/無 電源電壓:3 V ~ 3.6 V 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:16-TSSOP(0.173",4.40mm 寬) 供應商設備封裝:16-TSSOP 包裝:管件 其它名稱:23S08-5HPGG
ICS345R-XX 制造商:IDT 制造商全稱:Integrated Device Technology 功能描述:TRIPLE PLL FIELD PROGRAMMABLE SS VERSACLOCK SYNTHESIZER