SM802108

ClockWorks

™ 10GbE & GbE (156.25MHz,

125MHz) Ultra-Low Jitter, LVPECL

Frequency Synthesizer

ClockWorks is a trademark of Micrel, Inc

RotaryWave is a registered trademark of Multigig, Inc.

Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (

January 2011

M9999-012111-A

General Description

The SM802108 is a member of the ClockWorks

™ family of

devices from Micrel and provides an extremely low-noise

timing solution for GbE and 10GbE Ethernet clock signals.

It is based upon a unique patented RotaryWave

®

architecture that provides very low phase noise.

The device operates from a 3.3V or 2.5V power supply

and synthesizes two LVPECL output clocks at 156.25MHz

and another two at 125MHz. The SM802108 accepts a 25

MHz crystal or LVCMOS reference clock.

Data sheets and support documentation can be found on

Features

• Generates two LVPECL clock outputs at 156.25MHz

and two LVPECL clock outputs at 125MHz

• 2.5V or 3.3V operating range

• Typical phase jitter @ 156.25MHz

(1.875MHz to 20MHz): 110fs (typical) at 3.3V

• Industrial temperature range

• Green, RoHS, and PFOS compliant

• Available in 24-pin 4mm × 4mm QFN package

Applications

• 10Gigabit Ethernet

• Gigabit Ethernet

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