SY89856U

2GHz, Low-Power, 1:6 LVPECL Fanout Buffer

with 2:1 Input MUX and Internal Termination

Precision Edge is a registered trademark of Micrel, Inc.

Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com

August 2007

M9999-082907-C

General Description

The SY89856U is a 2.5V/3.3V precision, high-speed,

1:6 fanout capable of handling clocks up to 2.0GHz. A

differential 2:1 MUX input is included for redundant

clock switchover applications.

The differential input includes Micrel’s unique, 3-pin

input termination architecture that allows the device to

interface to any differential signal (AC- or DC-coupled)

shifting or termination resistor networks in the signal

path. The outputs are LVPECL (100k, temperature

compensated), with extremely fast rise/fall times

guaranteed to be less than 200ps.

The SY89856U operates from a 2.5V ±5% supply or a

3.3V ±10% supply and is guaranteed over the full

industrial temperature range of –40°C to +85°C. The

SY89856U is part of Micrel’s high-speed, Precision

Edge

All support documentation can be found on Micrel’s

Functional Block Diagram

Precision Edge

®

Features

• 6 ultra-low skew copies of the selected input

• 2:1 MUX input included for clock switchover

applications

• Low power: 225mW typical (2.5V)

• 2.5V to 3.3V supply voltage

• Unique input isolation design minimizes crosstalk

• Guaranteed AC performance over temperature and

voltage:

– Clock frequency range: DC to >2.0GHz

– <30ps skew (output-to-output)

• Ultra-low jitter design:

• Unique input termination and VT pin accepts DC-

and AC-coupled inputs (CML, PECL, LVDS)

• 100k LVPECL compatible output swing

• –40°C to +85°C industrial temperature range

• Available in 32-pin (5mm x 5mm) QFN package

Applications

• Redundant clock distribution

• All SONET/SDH clock/data distribution

• All Fibre Channel distribution

• All Gigabit Ethernet clock distribution

Markets

• LAN/WAN

• Enterprise servers

• ATE

• Test and measurement