- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄98027 > MPC92433FA (INTEGRATED DEVICE TECHNOLOGY INC) 1428 MHz, OTHER CLOCK GENERATOR, PQFP48 PDF資料下載
參數(shù)資料
| 型號： | MPC92433FA |
| 廠商： | INTEGRATED DEVICE TECHNOLOGY INC |
| 元件分類： | 時鐘產(chǎn)生/分配 |
| 英文描述： | 1428 MHz, OTHER CLOCK GENERATOR, PQFP48 |
| 封裝： | LQFP-48 |
| 文件頁數(shù)： | 8/20頁 |
| 文件大小： | 820K |
| 代理商： | MPC92433FA |
IDT / ICS DUAL LVPECL CLOCK SYNTHESIZER
16
MPC92433 REV. 3 NOVEMBER 10, 2008
MPC92433
1428MHZ DUAL OUTPUT LVPECL CLOCK SYNTHESIZER
VCC_PLL Filter
The MPC92433 is a mixed analog/digital product. Its analog
circuitry is naturally susceptible to random noise, especially if this
noise is seen on the power supply pins. Random noise on the
VCC_PLL pin impacts the device AC characteristics. The
MPC92433 provides separate power supplies for the digital
circuitry (VCC) and the internal PLL (VCC_PLL) of the device.
The purpose of this design technique is to isolate the high
switching noise digital outputs from the relatively sensitive internal
analog phase-locked loop. In digital system environments where
it is more difficult to minimize noise on the power supplies a
second level of isolation is recommended: a power supply filter on
the VCC_PLL pin for the MPC92433.
Figure 7. VCC_PLL Power Supply Filter
Figure 7 illustrates a recommended power supply filter
scheme.
The MPC92433 is most susceptible to noise with spectral
content in the 100 kHz to 1 MHz range. Therefore, the filter should
be designed to target this range. The key parameter that needs to
be met in the final filter design is the DC voltage drop that will be
seen between the VCC supply and the VCC_PLL pin of the
MPC92433. From the data sheet, the VCC_PLL current (the current
sourced through the VCC_PLL pin) is maximum 10 mA, assuming
that a minimum of 2.985 V must be maintained on the VCC_PLL
pin. The resistor shown in Figure 7 must have a resistance of 10–
15
to meet the voltage drop criteria. The minimum values for RF
and the filter capacitor CF are defined by the filter characteristics:
the RC filter should provide an attenuation greater than 40 dB for
noise whose spectral content is above 100 kHz. In the
recommended filter shown in Figure 7 the filter cut-off frequency
is around 3.0–4.5 kHz and the noise attenuation at 100 kHz is
better than 42 dB.
As the noise frequency crosses the series resonant point of an
individual capacitor its overall impedance begins to look inductive
and thus increases with increasing frequency. The parallel
capacitor combination shown ensures that a low impedance path
to ground exists for frequencies well above the bandwidth of the
PLL.
The On-Chip Crystal Oscillator
The MPC92433 features an integrated on-chip crystal oscillator
to minimize system implementation cost. The integrated oscillator
is a Pierce-type that uses the crystal in its parallel resonance
mode. It is recommended to use a 15 to 20 MHz crystal with a load
specification of CL = 10 pF. Crystals with a load specification of
CL = 20 pF may be used at the expense of an resulting slightly
higher frequency than specified for the crystal. Externally
connected capacitors on both the XTAL_IN and XTAL_OUT pins
are not required but can be used to fine-tune the crystal frequency
as desired.
The crystal, the trace and optional capacitors should be placed
on the board as close as possible to the MPC92433 XTAL_IN and
XTAL_OUT pins to reduce crosstalk of active signals into the
oscillator. Short and wide traces further reduce parasitic
inductance and resistance. It is further recommended to guard the
crystal circuit by placing a ground ring around the traces and
oscillator components.
RF = 10–15
VCC
CF = 22 F
10 nF
33...100 nF
VCC_PLL
VCC
MPC92433
7
Table 22. Recommended Crystal Specifications
Parameter
Value
Crystal Cut
Fundamental AT Cut
Resonance Mode
Parallel
Crystal Frequency
16–20 MHz
Shunt Capacitance C0
5–7 pF
Load Capacitance CL
10 pF
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| MPC92439FN | 900 MHz, OTHER CLOCK GENERATOR, PQCC28 |
| MPC92469FA | 400 MHz, OTHER CLOCK GENERATOR, PQFP32 |
| MPC92469AC | 400 MHz, OTHER CLOCK GENERATOR, PQFP32 |
| MPC92474FA | 700 MHz, OTHER CLOCK GENERATOR, PQFP48 |
| MPC972FA | 125 MHz, PROC SPECIFIC CLOCK GENERATOR, PQFP52 |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| MPC92439 | 制造商:IDT 制造商全稱:Integrated Device Technology 功能描述:900MHz, Low Voltage, LVPECL Clock Syntheesizer |
| MPC92439AC | 功能描述:IC SYNTHESIZER LVPECL 32-LQFP 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:- 標準包裝:1,000 系列:- 類型:時鐘/頻率合成器，扇出分配 PLL:- 輸入:- 輸出:- 電路數(shù):- 比率 - 輸入:輸出:- 差分 - 輸入:輸出:- 頻率 - 最大:- 除法器/乘法器:- 電源電壓:- 工作溫度:- 安裝類型:表面貼裝 封裝/外殼:56-VFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:56-VFQFP-EP（8x8） 包裝:帶卷 (TR) 其它名稱:844S012AKI-01LFT |
| MPC92439ACR2 | 功能描述:IC SYNTHESIZER LVPECL 32-LQFP 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:- 標準包裝:1,000 系列:- 類型:時鐘/頻率合成器，扇出分配 PLL:- 輸入:- 輸出:- 電路數(shù):- 比率 - 輸入:輸出:- 差分 - 輸入:輸出:- 頻率 - 最大:- 除法器/乘法器:- 電源電壓:- 工作溫度:- 安裝類型:表面貼裝 封裝/外殼:56-VFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:56-VFQFP-EP（8x8） 包裝:帶卷 (TR) 其它名稱:844S012AKI-01LFT |
| MPC92439EI | 功能描述:時鐘合成器/抖動清除器 FSL 900MHz LVPECL Freq. Synthesizer RoHS:否 制造商:Skyworks Solutions, Inc. 輸出端數(shù)量: 輸出電平: 最大輸出頻率: 輸入電平: 最大輸入頻率:6.1 GHz 電源電壓-最大:3.3 V 電源電壓-最小:2.7 V 封裝 / 箱體:TSSOP-28 封裝:Reel |
| MPC92439EIR2 | 功能描述:時鐘合成器/抖動清除器 FSL 900MHz LVPECL Freq. Synthesizer RoHS:否 制造商:Skyworks Solutions, Inc. 輸出端數(shù)量: 輸出電平: 最大輸出頻率: 輸入電平: 最大輸入頻率:6.1 GHz 電源電壓-最大:3.3 V 電源電壓-最小:2.7 V 封裝 / 箱體:TSSOP-28 封裝:Reel |
發(fā)布緊急采購，3分鐘左右您將得到回復。