SY88973BL_10 Datasheet, PDF (1/11 Pages) Micrel Semiconductor – 3.3V 3.2Gbps CML Low Power Limiting Post

SY88973BL
3.3V 3.2Gbps CML Low Power Limiting Post
Amplifier with TTL LOS
General Description
The SY88973BL 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 SY88973BL
quantizes these signals and outputs typically 800mV_PP
voltage-limited waveforms.
The SY88973BL operates from a single +3.3V ±10% power
supply, over an industrial temperature range of –40°C to
+85°C. With its wide bandwidth and high gain, signals with
data rates up to 3.2Gbps and as small as 10mV_PP can be
amplified to drive devices with CML inputs or AC-coupled
PECL inputs.
The SY88973BL incorporates a loss-of-signal (LOS), open-
collector TTL output with external 4.75kΩ to 10kΩ pull-up
resistor to fully comply with SFP MSA. 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 sets by LOSLVL and de-
asserts low otherwise. LOS can be fed back to the enable
(/EN) input to maintain output stability under a loss-of-signal
condition. /EN de-asserts the true output signal without
removing the input signal. Typically, 4.6dB LOS hysteresis is
provided to prevent chattering.
Please see Micrel’s website at www.micrel.com for a
complete selection of optical module ICs.
All support documentation can be found on Micrel’s web site
at: www.micrel.com.
Typical Performance
Features
• Multi-rate up to 3.2Gbps operation
• Wide gain-bandwidth product
• 38dB differential gain
• 2GHz 3dB bandwidth
• Low noise 50Ω CML data outputs
– 800mV_PP output swing
– 60ps edge rates
– 5ps_RMS typ. random jitter
– 15ps_PP typ. deterministic jitter
• Chatter-free, Loss-of-Signal (LOS) output
– No internal pull-up resistor− fully compliant with
SFP MSA
– 4.6dB electrical hysteresis
– OC-TTL output
• Programmable LOS sensitivity using single external
resistor
• Internal 50Ω data input termination
• TTL /EN input allows feedback from LOS
• Wide operating range:
– Single 3.3V ±10%
– –40°C to +85°C industrial temperature range
• Available in a tiny 3mm x 3mm 16-pin QFN package
Applications
• 1.25Gbps and 2.5Gbps Gigabit Ethernet
• 1.062Mbps and 2.125Gbps Fibre Channel
• 155Mbps, 622Gbps, 1.25Gbps, and 2.5Gbps
SONET/SDH
• Gigabit interface converter (GBIC)
• Small form factor (SFF) and small form factor pluggable
(SFP) transceivers
• Parallel 10G Ethernet
• High-gain line driver and line receiver
Markets
• Telecom/datacom
• Optical transceiver
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel [phone] • fax + 1 [phone] • http://www.micrel.com
February 2007
M9999-020207-A
[e-mail] or [phone]