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Precision Edge®

SY89831U

Micrel, Inc.

M9999-020707

hbwhelp@micrel.com or (408) 955-1690

DESCRIPTION

s Guaranteed AC performance over temperature

and voltage:

• DC-to > 2.0GHz throughput

• <450ps propagation delay (IN-to-Q)

• < 20ps within-device skew

• < 225ps rise/fall time

s Ultra-low jitter design:

• < 1ps

• < 1ps

• < 10ps

• < 10ps

s Unique patent-pending input termination and VT pin

accepts DC- and AC-coupled differential inputs

s 800mV, 100K LVPECL output swing

s Power supply 2.5V

s Industrial temperature range: –40

s Available in 16-pin (3mm

FEATURES

ULTRA-PRECISION 1:4 LVPECL

FANOUT BUFFER/TRANSLATOR

WITH INTERNAL TERMINATION

SY89831U

APPLICATIONS

s Processor clock distribution

s SONET clock distribution

s Fibre Channel clock distribution

s Gigabit Ethernet clock distribution

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The SY89831U is a high-speed, 2GHz differential

LVPECL 1:4 fanout buffer optimized for ultra-low skew

applications. Within device skew is guaranteed to be less

than 20ps (5ps typ.) over supply voltage and temperature.

The differential input buffer has a unique internal termination

design that allows access to the termination network through

a VT pin. This feature allows the device to easily interface

to different logic standards. A VREF–AC reference output is

included for AC-coupled applications.

The SY89831U is a part of Micrel's high-speed clock

synchronization family. For applications that require a

different I/O combination, consult Micrel’s website at

www.micrel.com, and choose from a comprehensive product

line of high-speed, low-skew fanout buffers, translators and

clock generators.

FUNCTIONAL BLOCK DIAGRAM

TYPICAL PERFORMANCE

Precision Edge is a registered trademark of Micrel, Inc.

MicroLeadFrame and MLF are trademarks of Amkor Technology, Inc.

155MHz Output

TIME (1ns/div.)

T

V

V

V

/Q

Q

IN

/IN

DQ

Q3

/Q3

Q2

/Q2

Q1

/Q1

Q0

/Q0

EN

(TTL/CMOS)

VT

50

Ω

50

Ω

VREF-AC

1:4

Rev.: D

Amendment: /0

Issue Date:

February 2007