General Description

The 840004-01 is a 4 output LVCMOS/LVTTL Synthesizer

optimized to generate Ethernet reference clock frequencies. Using

a 25MHz, 18pF parallel resonant crystal, the following frequencies

can be generated based on the 2 frequency select pins

(F_SEL1:0): 156.25MHz, 125MHz, and 62.5MHz. The 840004-01

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

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

meeting Ethernet jitter requirements. The 840004-01 is packaged

in a small 20-pin TSSOP package.

Features

• Four single-ended LVCMOS/LVTTL outputs

17 typical output impedance

• Selectable crystal oscillator interface or single-ended input

• Output frequency range: 56MHz - 175MHz

• VCO range: 560MHz - 700MHz

• RMS phase jitter at 156.25MHz (1.875MHz – 20MHz):

0.52ps (typical)

Phase Noise:

Offset Noise Power

100Hz -94.9 dBc/Hz

1kHz -119.6 dBc/Hz

10kHz -128.9 dBc/Hz

100kHz -129.2 dBc/Hz

• Full 3.3V or mixed 3.3V core/2.5V output supply modes

• 0°C to 70°C ambient operating temperature

• Available in lead-free (RoHS 6) package