SY88303BL

3.3V, 3.2Gbps CML Limiting Post Amplifier

with Wide Loss-of-Signal Detection Range

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

November 2007

M9999-110207-A

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

General Description

The SY88303BL low-power limiting post amplifiers are

designed for use in fiber-optic receivers. These devices

connect to typical transimpedance amplifiers (TIAs). The

linear signal output from TIAs can contain significant

amounts of noise and may vary in amplitude over time.

The SY88303BL quantizes these signals and output

CML-level waveforms.

The SY88303BL operates from a single +3.3V power

supply, over temperatures ranging from –40

With their wide bandwidth and high gain, signals with

be amplified to drive devices with CML/PECL inputs.

The device generates a loss-of-signal (LOS) open-

collector TTL output. The LOS function is optimized to

detect a wide input range, as shown in the typical

operating

characteristic

curve

on

Page

6.

A

the sensitivity of the input amplitude detection.

LOS asserts high if the input amplitude falls below the

The enable bar input (/EN) de-asserts the true output

signal without removing the input signal. The LOS

output can be fed back to the /EN input to maintain

output

stability

under

a

loss-of-signal

condition.

Typically, 3.5dB LOS hysteresis is provided to prevent

chattering.

Datasheet and support documentation can be found on

Micrel’s web site at: www.micrel.com.

Features

• Loss-of-signal detection circuit optimized to detect a

wide input range

• Chatter-free Open-Collector TTL Loss-of-Signal

(LOS) output

• Single 3.3V power supply

• 155Mbps to 3.2Gbps operation

• Low-noise CML data outputs

• Programmable LOS level set (LOS

• Available in a tiny 10-pin EPAD-MSOP and 16-pin

QFN package

Applications

• PON

• Gigabit Ethernet

• 1X and 2X Fibre Channel

• SONET/SDH: OC 3/12/24/48 – STM 1/4/8/16

• High-gain line driver and line receiver

Markets

• FTTX

• Optical transceivers

• Datacom/Telecom

• Low-gain TIA interface

• Long-reach FOM