Si570/Si571
10 MHZ TO 1.4 GHZ I2C PROGRAMMABLE XO/VCXO
Features
Any programmable output
frequencies from 10 to 945 MHz and
select frequencies to 1.4 GHz
Internal fixed crystal frequency
ensures high reliability and low
aging
Si5602
2
Available LVPECL, CMOS,
LVDS, and CML outputs
Industry-standard 5x7 mm
package
Pb-free/RoHS-compliant
1.8, 2.5, or 3.3 V supply
I C serial interface
®
3rd generation DSPLL with superior
jitter performance
3x better frequency stability than
SAW-based oscillators
Applications
Ordering Information:
SONET/SDH
xDSL
10 GbE LAN/WAN
ATE
High performance
instrumentation
Low-jitter clock generation
Optical modules
Clock and data recovery
See page 31.
Pin Assignments:
See page 30.
Description
(Top View)
®
The Si570 XO/Si571 VCXO utilizes Silicon Laboratories’ advanced DSPLL
circuitry to provide a low-jitter clock at any frequency. The Si570/Si571 are user-
programmable to any output frequency from 10 to 945 MHz and select frequencies
SDA
7
2
NC
VDD
1
2
3
6
5
4
to 1400 MHz with <1 ppb resolution. The device is programmed via an I C serial
interface. Unlike traditional XO/VCXOs where a different crystal is required for
each output frequency, the Si57x uses one fixed-frequency crystal and a DSPLL
clock synthesis IC to provide any-frequency operation. This IC-based approach
allows the crystal resonator to provide exceptional frequency stability and
reliability. In addition, DSPLL clock synthesis provides superior supply noise
rejection, simplifying the task of generating low-jitter clocks in noisy environments
typically found in communication systems.
OE
CLK–
CLK+
GND
8
SCL
Functional Block Diagram
Si570
CLK- CLK+
VDD
SDA
7
OE
VC
VDD
1
2
3
6
5
4
10-1400 MHz
DSPLLClock
Synthesis
Fixed
Frequency
XO
SDA
SCL
OE
CLK–
CLK+
Si571 only
GND
ADC
8
SCL
GND
Si571
VC
Rev. 1.6 6/18
Copyright © 2018 by Silicon Laboratories
Si570/Si571