P1819集成電路（IC）的時鐘發(fā)生器PLL頻率合成器規(guī)格書PDF中文資料

P1819屬于集成電路（IC）的時鐘發(fā)生器PLL頻率合成器。由安森美半導體公司制造生產的P1819時鐘發(fā)生器，PLL，頻率合成器時鐘發(fā)生器、PLL 和頻率合成器集成電路 (IC) 可為邏輯器件提供參考信號的穩(wěn)定定時脈沖，這些器件包括計算機、微控制器、數(shù)據通信系統(tǒng)和圖形/視頻發(fā)生器。這些集成電路可能包括緩沖器、驅動器、分頻器、倍頻器、多路復用器、合成器、扇出分配器和預分頻器。

Product Description

The P1819 is a Versatile Spread Spectrum Frequency Modulator designed specifically for input clock frequencies from 20 to 40MHz. (Refer to Input Frequency and Modulation Rate Table). The P1819 reduces electromagnetic interference (EMI) at the clock source, allowing system wide reduction of EMI of down stream clock and data dependent signals. The P1819 allows significant system cost savings by reducing the number of circuit board layers, ferrite beads, shielding, and other passive components that are traditionally required to pass EMI regulations.

The P1819 modulates the output of a single PLL in order to “spread” the bandwidth of a synthesized clock, and more importantly, decreases the peak amplitudes of its harmonics. This result in significantly lower system EMI compared to the typical narrow band signal produced by oscillators and most frequency generators. Lowering EMI by increasing a signal’s bandwidth is called ‘Spread Spectrum Clock Generation’.

The P1819 is available in different spread deviation, refer to Spread Deviation Selection Table.

The P1819 uses the most efficient and optimized modulation profile approved by the FCC and is implemented in a proprietary all digital method

Features

? FCC approved method of EMI attenuation.

? Provides up to 15dB EMI reduction.

? Generates a low EMI Spread Spectrum clock and a non-spread reference clock of the input frequency.

? Optimized for Frequency range from 20 to 40MHz.

? Internal loop filter minimizes external components and board space.

? Selectable spread options: Down and Center.

? Low Inherent Cycle-to-Cycle jitter.

? Two different deviation selections.

? ModRate is compliant with ATI M7x VGA spec.

? 3.3V ± 0.3V Operating Voltage range.

? Low power CMOS design.

? Supports notebook VGA and other LCD timing controller applications.

? Power Down function for mobile application.

? Available in 8-pin SOIC Package.

Applications

The P1819 is targeted towards EMI management for memory and LVDS interfaces in mobile graphic chipsets and high-speed digital applications such as PC peripheral devices, consumer electronics, and embedded controller systems.