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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 50
I/O termination
■ Programmable signal detect (SD and /SD) with 6dB
hysteresis
■ Chatter-free OC-TTL SD and /SD outputs with internal
5k
pull-up resistors can feedback to TTL enable
(/EN) input
■ Available in a tiny (3mm ××××× 3mm) 16-pin MLF
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
LVL)
sets the sensitivity of the input amplitude detection. SD asserts
high if the input amplitude rises above the threshold set by
SD
LVL and deasserts low otherwise. /SD is the complementary
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
VCC
/EN
GND
To
CDR
SY88953L
200k
From
Transimpedance
Amp.
DOUT
/DOUT
VCC
SDLVL
DIN
/DIN
0.1F
/SD
VTHP
VTHN
MicroLeadFrame and MLF are registered trademarks of Amkor Technology, Inc.