GENERAL DESCRIPTION

The 844001 is a Fibre Channel Clock Generator. The 844001 uses an

18pF parallel resonant crystal over the range of 20.4MHz - 28.3MHz.

For Fibre Channel applications, a 26.5625MHz crystal is used. The

frequency select pin allows the device to generate either 106.25MHz

or 212.5MHz from a 26.5625MHz crystal. To generate 187.5MHz for

12Gb Ethernet, a 23.4375MHz crystal is used. The 844001 uses IDT’s

3rd generation low phase noise VCO technology and can achieve

<1ps typical rms phase jitter, easily meeting Fibre Channel and

Ethernet jitter requirements. The 844001 is packaged in a small 8-pin

TSSOP, making it ideal for use in systems with limited board space.

NOTE: It is not recommended to overdrive the crystal input with an

external clock.

FEATURES

? One Differential LVDS output

? Crystal oscillator interface, 18pF parallel resonant crystal

(20.4MHz - 28.3MHz)

? Output frequency range: 81.66MHz - 226.66MHz

? VCO range: 490MHz - 680MHz

? RMS phase jitter @ 106.25MHz, using a 26.5625MHz crystal

(637kHz - 10MHz): 0.74ps (typical)

? 3.3V or 2.5V operating supply

? 0°C to 70°C ambient operating temperature

? Available in lead-free (RoHS 6) package

? For functional replacement part use 8T49N242

844001屬于集成電路（IC） > 時鐘發(fā)生器，PLL，頻率合成器。瑞薩科技有限公司制造生產的844001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、數據通信系統和圖形/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。