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hbwhelp@micrel.com or (408) 955-1690
DESCRIPTION
The SY88803V features:
■Single 3.3V or 5V power supply
■Up to 155Mbps operation
■Low noise PECL data outputs
■Chatter-free TTL Loss-of-Signal (LOS) output
■TTL /EN input
■Programmable LOS level set (LOS LVL)
■Available in a tiny 10-pin MSOP (3mm ××××
×3mm)
package
The SY88803V evaluation board features:
■AC-coupled I/O with SMA connectors
■50Ω input network termination
FUNCTIONAL FEATURES
3.3V/5V 155Mbps PECL
LOW-POWER LIMITING
POST AMPLIFIER W/TTL LOS
SY88803V
EVALUATION BOARD
AVAILABLE MEASUREMENTS
■Frequency performance
■Output eye pattern generation
■Mask testing
■Jitter
■Output rise/fall time
■BER testing
■Hysteresis measurement
Rev.: A Amendment: /0
Issue Date: March 2004
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 signicant 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 5mVpp can be
amplied to drive devices with PECL inputs.
The SY88803V generates a TTL LOS output. A
programmable, loss-of-signal, level set pin (LOSLVL) sets
the sensitivity of the input amplitude detection. LOS asserts
high if the input amplitude falls below the threshold set by
LOSLVL and de-asserts low otherwise. /EN de-asserts the
true output signal without removing the input signal. Typically
4.6dB loss-of-signal hysteresis is provided to prevent
chattering.
This manual provides information on the SY88803V
evaluation board. It should be used in conjunction with the
SY88803V datasheet, which contains full specications of
the SY88803V.
The SY88803V evaluation board enables fast and
thorough evaluation of the SY88803V 155Mbps PECL low-
power, limiting post amplier. The board is an easy-to-use,
single-layer, high-speed microstrip design. It is designed to
be driven by a high-speed, 155Mbps pattern generator and
provides onboard 50 terminations for the generator’sΩ
outputs. The input termination network also provides the
required input bias of VCC–1.3V for the SY88803V.
The SY88803V evaluation board is intended to be
terminated to a 50 scope and provides for simple userΩ
adjustability of the LOS threshold through the adjustment of
an on-board potentiometer. This allows the user to evaluate
various parameters of the SY88803V, as listed in the
"Available Measurements" section of this document.
All data sheets and support documentation can be found
on Micrel’s web site at www.micrel.com.
EVALUATION BOARD
Figure 1. SY88803V Evaluation Board
