SY88053AL Datasheet, PDF (1/12 Pages) Micrel Semiconductor – 3.3V, 12.5Gbps Limiting Post Amplifier with Programmable Decision Threshold

SY88053AL
3.3V, 12.5Gbps Limiting Post Amplifier
with Programmable Decision Threshold
General Description
The SY88053AL, limiting post amplifier is designed for
use in fiber-optic receivers for applications up to
12.5Gbps. It features a decision threshold control that
can be used for offset compensation or to optimize the
Bit Error Rate (BER) in noisy applications as WDM
where optical amplifiers such as EDFAs and Raman
amplifier are used. This device connects to typical
transimpedance amplifiers (TIAs). The signal from TIAs
can contain significant amounts of noise unevenly
distributed between its top and bottom rails due to the
Amplified Spontaneous Emission (ASE) noise generated
by the optical amplifiers. In order to optimize the BER in
such noisy conditions, the decision threshold between
bit 1 and bit 0 needs to be moved to the rail that
contains less noise. An external voltage applied at the
VTHP pin on the SY88053AL will move the crossing
point up and down, from 20% to 80%, to achieve the
best BER.
The SY88053AL operates from a single +3.3V power
supply, over temperatures ranging from –40^oC to +85^oC,
and can detect and amplify signals up to 12.5Gbps and
amplitude as low as 15mV_PP.
The SY88053AL generates a Loss-of-Signal (LOS)
open-collector TTL 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
de-asserts low otherwise. The enable 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 implement the squelch function that maintains output
stability under a loss-of-signal condition.
All support documentation can be found on Micrel’s web
site at: www.micrel.com.
Features
• Single 3.3V power supply
• Up to 12.5Gbps operation
• Programmable Decision Threshold
• Low-noise CML data outputs
• TTL /EN input
• Programmable LOS level (LOS_LVL)
• Available in a tiny 3mm x 3mm MLF^® package
Applications
• WDM Systems
• 10xGigabit Ethernet, 8xFibre Channel
• SONET/SDH:OC192 – STM64
• Low-gain TIA interface
Markets
• Datacom/telecom
• Optical transceiver
MLF and MicroLeadFrame are registered trademarks of Amkor Technology
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel [phone] • fax + 1 [phone] • http://www.micrel.com
May 2010
M9999-052610-A
[e-mail] or [phone]