SY88403BL
3.3V 4.25Gbps CML Low-Power Limiting
Post Amplifier with TTL LOS
General Description
Features
The SY88403BL is a low-power limiting post amplifier
optimized for copper applications. 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 SY88403BL quantizes these
signals and outputs typically 800mVPP voltage-limited
waveforms.
• Multi-rate up to 4.25Gbps operation
• 5mVPP input sensitivity
• Low noise 50Ω CML data outputs
– 800mV output swing
pp
– 60ps edge rates
– 1ps
typ. random jitter
RMS
– 10ps typ. deterministic jitter
PP
The SY88403BL 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 4.25Gbps and as
small as 5mVPP can be amplified to drive devices with
CML inputs or AC-coupled PECL inputs.
• Chatter-free Loss-of-Signal (LOS) output
– 3.5dB electrical hysteresis
– OC-TTL output with internal 4.75kΩ pull-up
resistor
• Programmable LOS sensitivity using single
The SY88403BL incorporates a loss-of-signal (LOS)
open-collector TTL output with internal 4.75kΩ pull-up
resistor. 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. LOS can be fed back to the enable bar
(/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, 3.5dB
LOS hysteresis is provided to prevent chattering.
external resistor
• Internal 50Ω data input termination
• TTL /EN input allows feedback from LOS
• Wide operating range:
– Single 3.3V ±10% power supply
– Industrial temperature range: –40°C to +85°C
• Available in a 10-pin EPAD-MSOP and 16-pin QFN
package
Applications
All support documentation can be found on Micrel’s
web site at: www.micrel.com.
• 1.062Gbps, 2.125Gbps and 4.25Gbps Fibre
Channel
• Cable driver
Typical Performance
• Small form factor (SFF) and small form factor
pluggable (SFP) transceivers
• High-gain line driver and line receiver
Markets
• Copper interconnect
• Datacom and telecom
• Storage area network (SAN)
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
M9999-111808-F
hbwhelp@micrel.com or (408) 955-1690
November 2008