参数资料
型号: MK2049-36SILF
厂商: INTEGRATED DEVICE TECHNOLOGY INC
元件分类: 时钟产生/分配
英文描述: 155.52 MHz, OTHER CLOCK GENERATOR, PDSO20
封装: 0.300 INCH, ROHS COMPLIANT, SOIC-20
文件页数: 4/8页
文件大小: 89K
代理商: MK2049-36SILF
MK2049-36
3.3 VOLT COMMUNICATIONS CLOCK PLL
VCXO AND SYNTHESIZER
IDT 3.3 VOLT COMMUNICATIONS CLOCK PLL
4
MK2049-36
REV G 051310
Frequency Locking to the Input
In all modes, the output clocks are frequency-locked to the input. The outputs will remain at the specified output frequency
as long as the combined variation of the input frequency and the crystal does not exceed 100 ppm. For example, if the
crystal can vary ±40 ppm (initial accuracy + temperature + aging), then the input frequency can vary by up to 60 ppm and
still have the output clock remain frequency-locked.
PC Board Layout
A proper board layout is critical to the successful use of the MK2049. In particular, the CAP1 and CAP2 pins are very
sensitive to noise and leakage (CAP2 at pin 18 is the most sensitive). Traces must be as short as possible and the two
capacitors and resistor must be mounted next to the device as shown below. The capacitor shown between pins 15 and 17,
and the one between pins 4 and 7 are the power supply decoupling capacitors. The high frequency output clocks on pins 8
and 9 should have a series termination of 33
Ω connected close to the pin. Additional improvements will come from keeping
all components on the same side of the board, minimizing vias through other signal layers, and routing other signals away
from the MK2049. You may also refer to application note MAN05 for additional suggestions on layout of the crystal selection.
The crystal traces should include pads for small capacitors from X1 and X2 to ground. These are used to adjust the stray
capacitance of the board to match the crystal load capacitance. The typical telecom reference frequency is accurate to
much less than 1 ppm, so the MK2049 may lock and run properly even if the board capacitance is not adjusted with these
fixed capacitors. However, IDT recommends that the adjustment capacitors be included to minimize the effects of variation
in individual crystals, temperature, and aging. The value of these capacitors (typically 0 - 4 pF) is determined once for a
given board layout, using the procedure found in application note MAN05 on the IDT web site.
External Component Selection
The MK2049-36 requires a minimum number of external components for proper operation. Decoupling capacitors of 0.01
μF
must be connected between VDD and GND pins close to the chip (especially pins 4 and 7, 15 and 17), and 33
Ω series
terminating resistors should be used on clock outputs with traces longer than one inch (assuming 50
Ωtraces). The selection
of additional external components is described in the following sections.
16
1
15
2
14
3
13
4
12
5
11
6
7
8
9
10
20
19
18
17
G
ca
p
ca
p
resist
cap
ca
p
ca
p
resist
V
G
cap
ca
p
Optional -
see text
Cutout in ground and power plane.
Route all traces away from this area.
V
= connect to VDD
G
= connect to GND
Figure 2. Typical MK2049-34 Layout
相关PDF资料
PDF描述
MK2049-44SILFTR 51.84 MHz, OTHER CLOCK GENERATOR, PDSO20
MK2049-44SILF 51.84 MHz, OTHER CLOCK GENERATOR, PDSO20
MK2049-44SITR 51.84 MHz, OTHER CLOCK GENERATOR, PDSO20
MK2049-44SI 51.84 MHz, OTHER CLOCK GENERATOR, PDSO20
MK2049-44SILF 51.84 MHz, OTHER CLOCK GENERATOR, PDSO20
相关代理商/技术参数
参数描述
MK2049-36SILFTR 功能描述:时钟合成器/抖动清除器 3.3 VOLT COMMUNICA. CLOCK VCXO PLL RoHS:否 制造商:Skyworks Solutions, Inc. 输出端数量: 输出电平: 最大输出频率: 输入电平: 最大输入频率:6.1 GHz 电源电压-最大:3.3 V 电源电压-最小:2.7 V 封装 / 箱体:TSSOP-28 封装:Reel
MK2049-36SITR 功能描述:IC VCXO PLL CLK SYNTH 20-SOIC RoHS:否 类别:集成电路 (IC) >> 时钟/计时 - 时钟发生器,PLL,频率合成器 系列:- 标准包装:39 系列:- 类型:* PLL:带旁路 输入:时钟 输出:时钟 电路数:1 比率 - 输入:输出:1:10 差分 - 输入:输出:是/是 频率 - 最大:170MHz 除法器/乘法器:无/无 电源电压:2.375 V ~ 3.465 V 工作温度:0°C ~ 70°C 安装类型:* 封装/外壳:* 供应商设备封装:* 包装:*
MK2049-45 制造商:ICS 制造商全称:ICS 功能描述:3.3V Communications Clock PLL
MK2049-45ASI 功能描述:IC CLK PLL COMM 3.3V 20-SOIC RoHS:否 类别:集成电路 (IC) >> 时钟/计时 - 时钟发生器,PLL,频率合成器 系列:- 标准包装:39 系列:- 类型:* PLL:带旁路 输入:时钟 输出:时钟 电路数:1 比率 - 输入:输出:1:10 差分 - 输入:输出:是/是 频率 - 最大:170MHz 除法器/乘法器:无/无 电源电压:2.375 V ~ 3.465 V 工作温度:0°C ~ 70°C 安装类型:* 封装/外壳:* 供应商设备封装:* 包装:*
MK2049-45ASILF 功能描述:时钟发生器及支持产品 3.3 VOLT COMMUNICA. CLOCK VCXO PLL RoHS:否 制造商:Silicon Labs 类型:Clock Generators 最大输入频率:14.318 MHz 最大输出频率:166 MHz 输出端数量:16 占空比 - 最大:55 % 工作电源电压:3.3 V 工作电源电流:1 mA 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:QFN-56