SM840051
10 Gigabit Ethernet Ultra-Low Jitter Clock
Synthesizer
General Description
The SM840051 clock synthesizer was designed for
Ethernet standards. The SM840051 is optimized for 77.76,
78.125, 80.56, 155.52, 156.25, and 161.13MHz, using a
crystal at 1/8th the output frequency. The SM840051
includes a unique power reduction methodology, along
with a patented RotaryWave™ architecture, that provides
a stable clock with very low noise for optimized
performance. This yields an overall improved Bit Error
Rate (BER) and improved waveform integrity.
Power supplies of either 3.3V or 2.5V are supported, with
superior jitter and phase noise performance. An FSEL pin
supports 4x or 8x multiplication of the crystal frequency.
The SM840051 provides ultra-low jitter, and consumes low
power.
Datasheets and support documentation can be found on
Micrel’s web site at: www.micrel.com.
Features
•
Generates a single LVCMOS/LVTTL output
•
Output Frequencies: 77.76, 78.125, 80.56, 155.52,
156.25, and 161.13MHz
•
RMS Phase Jitter at 156.25MHz( 1.875MHz-20MHz):
58fs (typical)
•
Integrated loop filter components
•
Operates with either a 3.3V or 2.5V supply
•
Power consumption is <77mA @ 3.3 V
•
Fundamental parallel resonant crystal
•
Crystal Frequencies: 20.141601MHz,19.53125MHz, and
19.44MHz
•
Industrial temperature range: –40°C to +75°C
•
Available in 8-pin TSSOP package
Applications
•
10 Gigabit Ethernet
•
SONET/SDH
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Block Diagram
RotaryWave is a trademark of Multigig, Inc.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (
408
) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
May 2010
M9999-050710-C
hbwhelp@micrel.com
or (408) 955-1690