PX5420
Multi-Rate TIA/LA Optical Receiver
Product Brief
September 2004
Description
The growing use of serial optical modules in
datacenter LAN and SAN infrastructures have
created a need for multi gigabit optical modules.
The introduction of 4 Gb/s Fiber Channel standard
for SANs is leading the data rate requirements for
current 1 Gb/s and 2 Gb/s optical modules while
demanding full backward compatibility.
The
Zarlink PX5420 multi-rate TIA/LA optical receiver
provides the performance and feature set required
by competitive SFF and SFP optical modules.
Features
The Zarlink PX5420 optical receiver is a single
channel TIA/LA optical receiver designed for
various applications to 4.25 Gb/s. It consists of a
transimpedance amplifier (TIA) and an AC-coupled
differential limiting amplifier (LA).
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Integrated transimpedance and limiting
amplifier for serial optical receiver
applications
•
Receiver sensitivity 10 µApp for 10-12 BER
at 4.25 Gb/s
The transimpedance amplifier achieves a nominal
bandwidth of 3 GHz over a wide range of
photodiode input capacitance. A photodiode bias
current monitor allows for a simple alignment
procedure.
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•
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Receive signal strength indicator (RSSI)
Loss of signal indicator (LOS)
Selectable squelch circuit disables output
at low input levels
The transimpedance amplifier is AC-coupled
internally to a high-gain, high-bandwidth, limiting
•
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Back-terminated 50-ohm CML output
amplifier.
The limiting amplifier provides a
Selectable 250 mV or 650 mV differential
output amplitude
differential back-terminated current-mode logic
(CML) output that can be used to drive a 4.25 Gb/s
intra module post amplifier or directly drive to the
edge of the module.
•
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No external passives required for
photodiode bias network
Single +3.3 V supply dissipating 100 mW
Full diagnostics are delivered through loss of
signal, squelch, and received signal strength
indicator circuits.
Applications
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•
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Receive optical sub-assemblies (ROSA)
4GFC, 2GFC, 1GFC, OC-48, GbE
SFP/SFF and proprietary optical modules
1
Zarlink Semiconductor Inc.
