3.3V, 3.2Gbps CML Limiting Post Amplifier
with High-Gain TTL Loss-of-Signal
The SY88343DL low-power, high-sensitivity, 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 SY88343DL quantizes these
signals and outputs CML level waveforms.
The SY88343DL operates from a single +3.3V power
supply, over temperatures ranging from –40oC to +85oC.
With its wide bandwidth, high gain, and signals with data
rates up to 3.2Gbps and as small as 5mVPP can be
amplified to drive devices with CML inputs or AC-
coupled CML/PECL inputs.
The SY88343DL generates a high-gain loss-of-signal
(LOS) open-collector TTL output. This function has a
high-gain input stage for increased LOS sensitivity. 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.
The enable bar input (/EN) de-asserts the true output
signal without removing the input signal. The LOS
output can be fed back to the /EN input to maintain
output stability under a loss-of-signal condition.
Typically, 3.5dB LOS hysteresis is provided to prevent
All support documentation can be found on Micrel’s web
site at: www.micrel.com.
• Single 3.3V power supply
• 155Mbps to 3.2Gbps operation
• Low-noise CML data outputs
• High-gain LOS
• Chatter-free open-collector TTL Loss-of-Signal (LOS)
output with internal 4.75kΩ pull-up resistor
• TTL /EN input
• Programmable LOS level set (LOSLVL)
• Ideal for mutil-rate applications
• Available in a tiny (3mm x 3mm) 16-pin QFN
• APON, BPON, EPON, GEPON, and GPON
• Gigabit Ethernet
• 1X and 2X Fibre Channel
• SONET/SDH : OC 3/12/24/48 – STM 1/4/8/16
• High-gain line driver and line receiver
• Optical transceivers
• Low-gain TIA interface
• Long reach FOM
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
firstname.lastname@example.org or (408) 955-1690