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® architecture that 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.

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