SY88803V_03 Datasheet, PDF (1/8 Pages) Micrel Semiconductor – 3.3V/5V 155Mbps PECL LOW POWER LIMITING POST AMPLIFIER W/TTL LOS

Micrel
3.3V/5V 155Mbps PECL LOW POWER
LIMITING POST AMPLIFIER W/TTL LOS
SY88803V
SY88803V
FEATURES
s Single 3.3V or 5V power supply
s Up to 155Mbps operation
s Low noise PECL data outputs
s Chatter-free TTL Loss-of-Signal (LOS) output
s TTL /EN input
s Programmable LOS level set (LOS_LVL)
s Available in a tiny 10-pin MSOP (3mm) package
APPLICATIONS
s 155Mbps SONET/SDH
s Small form factor transceivers
s High-gain line driver and line receiver
DESCRIPTION
The SY88803V 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 SY88803V
quantizes these signals and outputs PECL level waveforms.
The SY88803V 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 155Mbps and as small as 5mVp-p can be
amplified to drive devices with PECL inputs.
The SY88803V generates a TTL LOS output. A
programmable loss-of-signal level set pin (LOS_LVL) sets the
sensitivity of the input amplitude detection. LOS asserts
high if the input amplitude falls below the threshold set by
LOS_LVL and deasserts low otherwise. /EN deasserts the
true output signal without removing the input signal. Typically
4.6dB loss-of-signal hysteresis is provided to prevent
chattering.
TYPICAL APPLICATIONS CIRCUIT
From
Transimpedance
Amp.
0.1µF
0.1µF
50Ω
V_CC
2kΩ
LOS
D_IN
/D_IN
V_CC
/EN
SY88803V
D_OUT
/D_OUT
0.1µF
0.1µF
50Ω
GND
LOS_LVL V_REF
R_pd
R_pd
V_CC
100Ω 3kΩ
GND
For 3.3V, R_pd = 120Ω
For 5V, R_pd = 220Ω
To
CDR
Rev.: A Amendment: /0
1
Issue Date: March 2003