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SY88933V

Micrel, Inc.

M9999-011508

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

3.3V/5V 1.25Gbps PECL LOW-POWER

LIMITING POST AMPLIFIER

WITH TTL SIGNAL DETECT

SY88933V

Rev.: D

Amendment: /0

Issue Date: January 2008

TYPICAL APPLICATIONS CIRCUIT

APPLICATIONS

■ 1.25Gbps Ethernet

■ 1.55Mbps and 622Mbps SONET/SDH

■ High-gain line driver and line receiver

■ 531Mbps and 1062Mbps Fibre Channel

■ Gigabit interface converter

■ Single 3.3V or 5V power supply

■ DC to 1.25Gbps operation

■ Low noise PECL data outputs

■ Chatter-free OC-TTL signal setect (SD) output with

internal 6.75k

■ TTL EN input

■ Programmable SD level set (SD

■ Available in a tiny 10-pin MSOP (3mm) package

FEATURES

DESCRIPTION

The SY88933V low-power limiting post amplifier is

designed for use in fiber-optic receivers. The device

connects 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 SY88933V quantizes these signals and outputs PECL

level waveforms.

The SY88933V operates from a single +3.3V or +5V

power supply, over temperatures ranging from –40°C to

+85°C. With its wide bandwidth and high gain, signals

with data rates up to 1.25Gbps and as small as 5mVp-p

can be amplified to drive devices with PECL inputs.

The SY88933V generates a TTL SD output. A

programmable signal-detect level set pin (SD

the sensitivity of the input amplitude detection. SD asserts

high if the input amplitude rises above the threshold set

by SD

the true output signal without removing the input signal.

Typically, 4.6dB SD hysteresis is provided to prevent

chattering.

EN

GND

GND

To

CDR

SY88933V

100kΩ

0.1µF

From

Transimpedance

Amp.

0.1µF

0.1µF

0.1µF

0.1µF

SD

50Ω

50Ω