General Description

The 843252 is a 2 differential output LVPECL Synthesizer designed

to generate Ethernet reference clock frequencies. Using a 25MHz,

18pF parallel resonant crystal, the following frequencies can be

generated based on the settings of 4 frequency select pins

(SELA[1:0], SELB[1:0]): 625MHz, 312.5MHz, 156.25MHz, and

125MHz.

The two banks have their own dedicated frequency select pins and

can be independently set for the frequencies mentioned above. The

843252 IDT’s 3rd generation low phase noise VCO technology and

can achieve 1ps or lower typical rms phase jitter, easily meeting

Ethernet jitter requirements. The 843252 is packaged in a small

16-pin TSSOP package.

Features

• Two differential LVPECL output pairs

• Using a 25MHz crystal, the two output banks can be

independently set for 625MHz, 312.5MHz, 156.25MHz or 125MHz

• Crystal oscillator interface

• VCO frequency: 490MHz – 680MHz

• RMS Phase Jitter @ 156.25MHz, (1.875MHz – 20MHz) using a

25MHz crystal: 0.47ps (typical)

• Full 3.3V supply mode

• 0°C to 70°C ambient operating temperature

• Industrial temperature available upon request

• Available in lead-free (RoHS 6) package

843252属于集成电路（IC） > 时钟发生器，PLL，频率合成器。瑞萨科技有限公司制造生产的843252时钟发生器，PLL，频率合成器时钟发生器、PLL 和频率合成器集成电路 (IC) 可为逻辑器件提供参考信号的稳定定时脉冲，这些器件包括计算机、微控制器、数据通信系统和图形/视频发生器。这些集成电路可能包括缓冲器、驱动器、分频器、倍频器、多路复用器、合成器、扇出分配器和预分频器。