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SY88953L

Micrel, Inc.

M9999-081506

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

3.3V 10.7Gbps CML LIMITING POST

AMPLIFIER W/ TTL SD AND /SD

SY88953L

Rev.: C

Amendment: /0

Issue Date:

August 2006

TYPICAL APPLICATIONS CIRCUIT

APPLICATIONS

■ OC-192SDH/SONET

■ 10G Ethernet/Fibre Channel receivers

■ Upto 10.7Gbps proprietary link

■ XFP transceivers

■ Line driver/receiver

■ Single 3.3V power supply

■ Up to 10.7Gbps operation

■ 800mVp-p output swing with 30ps edge rates

■ 28dB voltage gain with 5mVp-p input sensitivity

■ On chip 50Ω

Ω

Ω

Ω

Ω I/O termination

■ Programmable signal detect (SD and /SD) with 6dB

hysteresis

■ Chatter-free OC-TTL SD and /SD outputs with internal

5kΩ

Ω

Ω

Ω

Ω pull-up resistors can feedback to TTL enable

(/EN) input

package or die

FEATURES

DESCRIPTION

The SY88953L high-speed 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 SY88953L quantizes

these signals and outputs CML level waveforms.

The SY88953L operates from a single +3.3V power supply,

over temperatures ranging from –40°C to +85°C. With its

wide bandwidth and high gain, signals with data rates up to

10.7Gbps and as small as 5mVp-p can be amplified to drive

devices with CML inputs.

The SY88953L outputs TTL signal-detect (SD and /SD)

signals. A programmable signal-detect level set pin (SD

sets the sensitivity of the input amplitude detection. SD asserts

high if the input amplitude rises above the threshold set by

SD

output of SD. /SD can be fedback to the enable (/EN) input

to maintain output stability under a loss of signal condition.

/EN deasserts the true output signal without removing the

input signal. Typically 6dB SD hysteresis is provided to

prevent chattering.

The SY88953L also includes an input threshold

adjustment to correct pulsewidth distortion.

SD

/EN

GND

To

CDR

SY88953L

200kΩ

From

Transimpedance

Amp.

0.1µF

0.1µF

0.1µF

0.1µF

/SD

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