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Rev. 1.0 4/15 Copyright © 2015 by Silicon Laboratories Si5351A/B/C-B
Si5351A/B/C-B
I
2
C-PROGRAMMABLE ANY-FREQUENCY CMOS CLOCK
GENERATOR + VCXO
Features
Applications
Description
The Si5351 is an I
2
C configurable clock generator that is ideally suited for replacing
crystals, crystal oscillators, VCXOs, phase-locked loops (PLLs), and fanout buffers in
cost-sensitive applications. Based on a PLL/VCXO + high resolution MultiSynth fractional
divider architecture, the Si5351 can generate any frequency up to 200 MHz on each of its
outputs with 0 ppm error. Three versions of the Si5351 are available to meet a wide
variety of applications. The Si5351A generates up to 8 free-running clocks using an
internal oscillator for replacing crystals and crystal oscillators. The Si5351B adds an
internal VCXO and provides the flexibility to replace both free-running clocks and
synchronous clocks. It eliminates the need for higher cost, custom pullable crystals while
providing reliable operation over a wide tuning range. The Si5351C offers the same
flexibility but synchronizes to an external reference clock (CLKIN).
Functional Block Diagram
www.silabs.com/custom-timing
Generates up to 8 non-integer-related
frequencies from 2.5 kHz to 200 MHz
I
2
C user definable configuration
Exact frequency synthesis at each output
(0 ppm error)
Highly linear VCXO
Optional clock input (CLKIN)
Low output period jitter: < 70 ps pp, typ
Configurable spread spectrum selectable
at each output
Operates from a low-cost, fixed frequency
crystal: 25 or 27 MHz
Supports static phase offset
Programmable rise/fall time control
Glitchless frequency changes
Separate voltage supply pins provide
level translation:
Core VDD: 2.5 or 3.3 V
Output VDDO: 1.8, 2.5, or 3.3 V
Excellent PSRR eliminates external
power supply filtering
Very low power consumption
Adjustable output delay
Available in 2 packages types:
10-MSOP: 3 outputs
20-QFN (4x4 mm): 8 outputs
PCIE Gen 1 compatible
Supports HCSL compatible swing
HDTV, DVD/Blu-ray, set-top box
Audio/video equipment, gaming
Printers, scanners, projectors
Handheld Instrumentation
Residential gateways
Networking/communication
Servers, storage
XO replacement
R0
R1
CLK0
CLK1
VDDOA
R2
R3
CLK2
CLK3
VDDOB
R4
R5
CLK4
CLK5
VDDOC
R6
R7
CLK6
CLK7
VDDOD
MultiSynth
0
MultiSynth
1
MultiSynth
2
MultiSynth
3
MultiSynth
4
MultiSynth
5
MultiSynth
6
MultiSynth
7
PLL
A
PLL
B
XA
XB
OSC
CLKIN
SCL
SDA
Control
Logic
INTR
OEB
I
2
C
Si5351C (20-QFN)
OSC
XA
XB
PLL
VCXO
R0
R1
CLK0
CLK1
VDDOA
R2
R3
CLK2
CLK3
VDDOB
R4
R5
CLK4
CLK5
VDDOC
R6
R7
CLK6
CLK7
VDDOD
MultiSynth
0
MultiSynth
1
MultiSynth
2
MultiSynth
3
MultiSynth
4
MultiSynth
5
MultiSynth
6
MultiSynth
7
VC
SCL
SDA
Control
Logic
OEB
SSEN
I
2
C
Si5351B (20-QFN)
Ordering Information:
See page 29
10-MSOP
20-QFN
页面指南
