Si570/Si571 2 10 MHZ TO 1.4 GHZ I C PROGRAMMABLE XO/VCXO Features Any programmable output Internal fixed crystal frequency frequencies from 10 to 945 MHz and ensures high reliability and low Si5602 select frequencies to 1.4 GHz aging 2 Available LVPECL, CMOS, I C serial interface LVDS, and CML outputs 3rd generation DSPLL with superior Industry-standard 5x7 mm jitter performance package 3x better frequency stability than Pb-free/RoHS-compliant SAW-based oscillators 1.8, 2.5, or 3.3 V supply Applications Ordering Information: SONET/SDH High performance See page 31. xDSL instrumentation 10 GbE LAN/WAN Low-jitter clock generation ATE Optical modules Pin Assignments: Clock and data recovery See page 30. Description (Top View) The Si570 XO/Si571 VCXO utilizes Silicon Laboratories advanced DSPLL SDA circuitry to provide a low-jitter clock at any frequency. The Si570/Si571 are user- 7 programmable to any output frequency from 10 to 945 MHz and select frequencies 2 NC 1 6 V to 1400 MHz with <1 ppb resolution. The device is programmed via an I C serial DD 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 OE 2 5 CLK 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 GND 3 4 CLK+ rejection, simplifying the task of generating low-jitter clocks in noisy environments 8 typically found in communication systems. SCL Functional Block Diagram Si570 CLK- CLK+ V DD SDA 7 OE V C 1 6 V DD 10-1400 MHz Fixed Frequency DSPLL Clock SDA XO Synthesis SCL OE 2 5 CLK Si571 only GND 3 4 CLK+ ADC 8 SCL GND Si571 V C Rev. 1.6 6/18 Copyright 2018 by Silicon Laboratories Si570/Si571Si570/Si571 TABLE OF CONTENTS Section Page 1. Detailed Block Diagrams .3 2. Electrical Specifications .4 3. Functional Description .14 3.1. Programming a New Output Frequency 14 3.2. Si570 Programming Procedure .18 3.3. Si570 Troubleshooting FAQ .20 2 3.4. I C Interface .21 4. Serial Port Registers .22 5. Si570 (XO) Pin Descriptions .29 6. Si571 (VCXO) Pin Descriptions .30 7. Ordering Information .31 8. Si57x Mark Specification 32 9. Outline Diagram and Suggested Pad Layout .33 10. 8-Pin PCB Land Pattern 34 Revision History .35 2 Rev. 1.6