SY54020AR

Low Voltage 1.2V/1.8V/2.5V CML 1:4 Fanout

Buffer with /EN 3.2Gbps, 3.2GHz

Precision Edge is a registered trademark of Micrel, Inc.

MLF and MicroLeadFrame are registered trademarks of Amkor Technology.

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

April 2009

M9999-041409-A

General Description

The SY54020AR is a fully differential, low voltage

1.2V/1.8V/2.5V CML 1:4 Fanout Buffer with active-low

Enable (/EN). The Enable is synchronous so that the

outputs will only be enabled/disabled when they are

already in the LOW state. This avoids any chance of

generating a runt clock pulse when the device is

enabled/disabled as can happen with an asynchronous

control. When this device is used as a clock fanout,

disabling the downstream clock may reduce system

power. The SY54020AR can process clock signals as

fast as 3.2 GHz or data patterns up to 3.2Gbps.

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

input termination architecture that interfaces to LVPECL,

LVDS or CML differential signals as small as 100mV

resistor networks in the signal path. For AC-coupled

input

interface

applications,

an

internal

voltage

CML, with extremely fast rise/fall times guaranteed to be

less than 100ps.

The SY54020AR operates from a 2.5V ±5% core supply

and a 1.2V, 1.8V or 2.5V ±5% output supply and is

guaranteed over the full industrial temperature range (–

40°C to +85°C).

Datasheets and support documentation can be found on

Functional Block Diagram

Precision Edge

®

Features

• 1.2V/1.8V/2.5V CML 1:4 Fanout Buffer

• Active-low Enable (/EN) input to disable the outputs

• Guaranteed AC performance over temperature and

voltage:

– DC-to > 3.2Gbps Data throughput

– DC-to > 3.2GHz Clock throughput

– <320 ps propagation delay (IN-to-Q)

– <20ps within-device skew

– <100 ps rise/fall times

• Ultra-low jitter design

• High-speed CML outputs

• 2.5V ±5% V

operation

• Industrial temperature range: –40°C to +85°C

Applications

• SONET clock and data distribution

• Fibre Channel clock and data distribution

• Gigabit Ethernet clock and data distribution

Markets

• Storage

• ATE

• Test and measurement

• Enterprise networking equipment

• High-end servers

• Access

• Metro area network equipment