Low Power, 3GHz, 1:2 LVPECL Fanout
Buffer/Translator with Internal Termination
The SY89851U is a low jitter, low skew, high-speed
1:2 differential fanout buffer optimized for precision
telecom and enterprise server distribution
applications. The SY89851U distributes clock
frequencies from DC to >3GHz, and data rates to
2.5Gbps guaranteed over temperature and voltage.
The SY89851U differential input includes Micrel's
unique, 3-pin input termination architecture that
directly interfaces to any differential signal (AC- or
DC-coupled) as small as 100mV (200mVpp) without
any level shifting or termination resistor networks in
the signal path. The outputs are 800mV, 100K-
compatible LVPECL with extremely fast rise/fall time
guaranteed to be less than 180ps.
The SY89851U operates from a 2.5V ±5% or 3.3V
±10% supply and is guaranteed over the full
industrial temperature range of –40°C to +85°C. The
SY89851U is part of Micrel's high-speed, Precision
Edge® product line.
All support documentation can be found on Micrel's
web site at www.micrel.com.
Functional Block Diagram
• Precision 1:2, 800mV LVPECL fanout buffer
• Low power consumption: 80mW typ. (2.5V)
• Guaranteed AC performance over temperature
– DC to >3GHz clock throughput
– <340ps propagation delay
– <180ps rise/fall time
– <20ps output-to-output skew
• Ultra-low jitter design:
– <1psRMS random jitter
– <10psPP deterministic jitter
– <10psPP total jitter (clock)
• Unique, patented input termination and VT pin
accepts DC- and AC-coupled inputs (CML,
• 100K LVPECL-compatible outputs
• Power supply 2.5V ±5% or 3.3V ±10%
• –40°C to +85°C industrial temperature range
• Available in 16-pin (3mm x 3mm) MLF™ package
• All SONET and GigE clock distribution
• Fibre Channel applications
• Backplane distribution
• High-end, low skew, multiprocessor synchronous
Precision Edge is a registered trademark of Micrel, Inc.
MicroLeadFrame and MLF are trademarks of Amkor Technology, Inc.
firstname.lastname@example.org or (408) 955-1690