參數(shù)資料
型號: ADCLK944BCPZ-WP
廠商: Analog Devices Inc
文件頁數(shù): 2/12頁
文件大?。?/td> 0K
描述: IC CLOCK BUFFER 1:4 7GHZ 16LFCSP
標(biāo)準(zhǔn)包裝: 50
系列: SIGe
類型: 扇出緩沖器(分配)
電路數(shù): 1
比率 - 輸入:輸出: 1:4
差分 - 輸入:輸出: 是/是
輸入: CML,CMOS,LVDS,LVPECL
輸出: ECL,LVPECL
頻率 - 最大: 7GHz
電源電壓: 2.375 V ~ 3.63 V
工作溫度: -40°C ~ 85°C
安裝類型: 表面貼裝
封裝/外殼: 16-WFQFN 裸露焊盤,CSP
供應(yīng)商設(shè)備封裝: 16-LFCSP-WQ(3x3)
包裝: 托盤 - 晶粒
ADCLK944
Rev. 0 | Page 10 of 12
PCB LAYOUT CONSIDERATIONS
The ADCLK944 buffer is designed for very high speed applica-
tions. Consequently, high speed design techniques must be used
to achieve the specified performance. It is critically important to
use low impedance supply planes for both the negative supply
(VEE) and the positive supply (VCC) planes as part of a multilayer
board. Providing the lowest inductance return path for switching
currents ensures the best possible performance in the target
application.
The following references to the ground plane assume that the VEE
power plane is grounded for LVPECL operation. Note that, for
ECL operation, the VCC power plane becomes the ground plane.
It is also important to adequately bypass the input and output
supplies. Place a 1 μF electrolytic bypass capacitor within several
inches of each VCC power supply pin to the ground plane. In
addition, place multiple high quality 0.001 μF bypass capacitors
as close as possible to each VCC supply pin, and connect the
capacitors to the ground plane with redundant vias. Select high
frequency bypass capacitors for minimum inductance and ESR.
To improve the effectiveness of the bypass at high frequencies,
minimize parasitic layout inductance. Also, avoid discontinuities
along input and output transmission lines; such discontinuities
can affect jitter performance.
In a 50 Ω environment, input and output matching have a signif-
icant impact on performance. The buffer provides internal 50 Ω
termination resistors for both the CLK and CLK inputs. Normally,
the return side is connected to the reference pin that is provided.
Bypass the termination potential using ceramic capacitors to
prevent undesired aberrations on the input signal due to parasitic
inductance in the termination return path. If the inputs are dc-
coupled to a source, take care to ensure that the pins are within
the rated input differential and common-mode voltage ranges.
If the return is floated, the device exhibits a 100 Ω cross-termi-
nation, but the source must then control the common-mode
voltage and supply the input bias currents.
ESD/clamp diodes between the input pins prevent the application
from developing excessive offsets to the input transistors. ESD
diodes are not optimized for best ac performance. When a clamp
is required, it is recommended that appropriate external diodes
be used.
Exposed Metal Paddle
The exposed metal paddle on the ADCLK944 package is both an
electrical connection and a thermal enhancement. For the device
to function properly, the paddle must be properly attached to
the VEE pins.
When properly mounted, the ADCLK944 also dissipates heat
through its exposed paddle. The PCB acts as a heat sink for the
ADCLK944. The PCB attachment must provide a good thermal
path to a larger heat dissipation area. This requires a grid of vias
from the top layer of the PCB down to the VEE power plane (see
Figure 17). The ADCLK944 evaluation board (ADCLK944/PCBZ)
provides an example of how to attach the part to the PCB.
VIAS TO VEE POWER
PLANE
08
77
0-
01
8
Figure 17. PCB Land for Attaching Exposed Paddle
相關(guān)PDF資料
PDF描述
ADN4670BCPZ IC CLOCK BUFFER MUX 2:10 16LFCSP
ADCLK846BCPZ IC CLK BUFFER 1:6 1.2GHZ 24LFCSP
ADCLK925BCPZ-WP IC CLOCK/DATA BUFFER 1:2 16LFCSP
VI-25N-MW-F1 CONVERTER MOD DC/DC 18.5V 100W
VI-24X-MW-F3 CONVERTER MOD DC/DC 5.2V 100W
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
ADCLK946 制造商:AD 制造商全稱:Analog Devices 功能描述:Six LVPECL Outputs, SiGe Clock Fanout Buffer
ADCLK946/PCBZ 功能描述:KIT EVAL CLK BUFF ADCLK946 RoHS:是 類別:編程器,開發(fā)系統(tǒng) >> 評估演示板和套件 系列:- 標(biāo)準(zhǔn)包裝:1 系列:- 主要目的:電信,線路接口單元(LIU) 嵌入式:- 已用 IC / 零件:IDT82V2081 主要屬性:T1/J1/E1 LIU 次要屬性:- 已供物品:板,電源,線纜,CD 其它名稱:82EBV2081
ADCLK946BCPZ 功能描述:IC CLK BUFFER 1:6 4.8GHZ 24LFCSP RoHS:是 類別:集成電路 (IC) >> 時鐘/計時 - 時鐘緩沖器,驅(qū)動器 系列:SIGe 標(biāo)準(zhǔn)包裝:74 系列:- 類型:扇出緩沖器(分配) 電路數(shù):1 比率 - 輸入:輸出:1:10 差分 - 輸入:輸出:是/是 輸入:HCSL, LVCMOS, LVDS, LVPECL, LVTTL 輸出:HCSL,LVDS 頻率 - 最大:400MHz 電源電壓:3 V ~ 3.6 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:32-VFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:32-QFN(5x5) 包裝:管件
ADCLK946BCPZ-REEL7 功能描述:IC CLK BUFFER 1:6 4.8GHZ 24LFCSP RoHS:是 類別:集成電路 (IC) >> 時鐘/計時 - 時鐘緩沖器,驅(qū)動器 系列:SIGe 標(biāo)準(zhǔn)包裝:74 系列:- 類型:扇出緩沖器(分配) 電路數(shù):1 比率 - 輸入:輸出:1:10 差分 - 輸入:輸出:是/是 輸入:HCSL, LVCMOS, LVDS, LVPECL, LVTTL 輸出:HCSL,LVDS 頻率 - 最大:400MHz 電源電壓:3 V ~ 3.6 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:32-VFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:32-QFN(5x5) 包裝:管件
ADCLK948 制造商:AD 制造商全稱:Analog Devices 功能描述:Two Selectable Inputs, 8 LVPECL Outputs, SiGe Clock Fanout Buffer