SM802117

ClockWorks

™ GbE (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 (

October 2011

M9999-101311-B

General Description

The SM802117 is a member of the ClockWorks

™ family of

devices from Micrel and provides an extremely low-noise

timing solution for GbE Ethernet clock signals. It is based

upon a unique patented RotaryWave

provides very low phase noise.

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

and synthesizes LVPECL output clocks at 125MHz. There

are two differential clock outputs each with it’s own OE pin

allowing them to be disabled independently. The

SM802117 accepts a 25 MHz crystal or LVCMOS

reference clock.

Data sheets and support documentation can be found on

Micrel’s web site at:

HU

www.micrel.com

UH

.

Features

• Generates one or two LVPECL clock outputs at 125MHz

• 2.5V or 3.3V operating range

• Typical phase jitter @ 125MHz

(1.875MHz to 20MHz): 115fs

• Industrial temperature range (–40°C to +85°C)

• Green, RoHS, and PFOS compliant

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

Applications

• Gigabit Ethernet - PHY

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