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SY89875U

Micrel, Inc.

M9999-082407

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

DESCRIPTION

Integrated programmable clock divider and 1:2

fanout buffer

Guaranteed AC performance over temperature and

voltage:

• > 2.0GHz f

MAX

• < 15ps within device skew

Low jitter design:

• < 10ps

• < 1ps

Unique input termination and V

and AC-coupled Inputs; CML, PECL, LVDS and

HSTL

LVDS compatible outputs

TTL/CMOS inputs for select and reset

Parallel programming capability

Programmable divider ratios of 1, 2, 4, 8 and 16

Low voltage operation 2.5V

Output disable function

–40°C to 85°C temperature range

FEATURES

2.5V, 2.0GHz ANY DIFF. IN-TO-LVDS

PROGRAMMABLE CLOCK DIVIDER AND 1:2

FANOUT BUFFER W/ INTERNAL TERMINATION

SY89875U

APPLICATIONS

SONET/SDH line cards

Transponders

High-end, multiprocessor servers

Rev.: D

Amendment: /0

Issue Date:

August 2007

This low-skew, low-jitter device is capable of accepting a

high-speed (e.g., 622MHz or higher) CML, LVPECL, LVDS

or HSTL clock input signal and dividing down the frequency

using a programmable divider to create a lower speed

version of the input clock. Available divider ratios are 2, 4, 8

and 16, or straight pass-through.

The differential input buffer has a unique internal

termination design that allows access to the termination

network through a V

easily interface to different logic standards. A V

REF-AC

reference is included for AC-coupled applications.

The /RESET input asynchronously resets the divider. In

the pass-through function (divide by 1) the /RESET

synchronously enables or disables the outputs on the next

falling edge of IN (rising edge of /IN).

FUNCTIONAL BLOCK DIAGRAM

TYPICAL PERFORMANCE

Precision Edge is a registered trademark of Micrel, Inc.

MicroLeadFrame and MLF are registered trademarks of Amkor Technology, Inc.

IN

/IN

S1

S0

Q1

/Q1

Q0

/Q0

509

509

/RESET

S2

Divided

by

2, 4, 8

or 16

Enable

MUX

MUX

Enable

FF

Decoder

Divide-by-4

CML/LVPECL/LVDS

622MHz

Clock In

OC-12 to OC-3

Translator/Divider

LVDS

155.5MHz

Clock Out

622MHz In

/Q0

Q0

/IN

IN

155.5MHz Out