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
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
I2C 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 Skyworks Solutions’ 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
to 1400 MHz with <1 ppb resolution. The device is programmed via an I2C 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.
SDA
7
NC
VDD
1
2
3
6
5
4
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
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
Rev. 1.6 • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice • November 15, 2021