FemtoClock® Crystal-to-LVDS Frequency Synthesizer W/Integrated Fanout Buffer

The 844256DI is a Crystal-to-LVDS Clock Synthesizer/Fanout Buffer designed for SONET and Gigabit Ethernet applications. The output frequency can be set using the frequency select pins and a 25MHz crystal for Ethernet frequencies, or a 19.44MHz crystal for SONET. The low phase noise characteristics of the 844256DI make it an ideal clock for these demanding applications.

Features

  • Six differential LVDS output pairs
  • Crystal oscillator interface
  • Output frequency range: 62.5MHz - 625MHz
  • Crystal input frequency range:15.625MHz - 25.5MHz
  • RMS phase jitter @ 125MHz, using a 25MHz crystal (1.875MHz – 20MHz): 0.43ps (typical)
  • Full 3.3V or mixed 3.3V core, 2.5V output supply mode
  • -40°C to 85°C ambient operating temperature
  • Available in lead-free (RoHS 6) package

Product Options

Orderable Part ID Part Status Pkg. Code Pkg. Type Lead Count (#) Temp. Grade Pb (Lead) Free Carrier Type Buy Sample
844256DGILF Active EJG24 TSSOP 24 I Yes Tube Availability
844256DGILFT Active EJG24 TSSOP 24 I Yes Reel Availability

Technical Documentation

Title Other Languages Type Format File Size Date
Datasheets & Errata
ICS844256DI Datasheet Datasheet PDF 911 KB Aug 4, 2010
Application Notes & White Papers
AN-828 Termination - LVPECL Application Note PDF 229 KB Jul 5, 2016
AN-831 The Crystal Load curve Application Note PDF 308 KB Sep 22, 2014
AN-846 Termination - LVDS Application Note PDF 50 KB May 12, 2014
AN-842 Thermal Considerations in Package Design and Selection Application Note PDF 403 KB May 11, 2014
AN-803 Crystal Timing Budget and Accuracy for IDT Timing Clock Products Application Note PDF 44 KB May 7, 2014
AN-840 Jitter Specifications for Timing Signals Application Note PDF 349 KB May 7, 2014
AN-839 RMS Phase Jitter Application Note PDF 149 KB May 6, 2014
AN-838 Peak-to-Peak Jitter Calculations Application Note PDF 32 KB May 6, 2014
AN-834 Hot-Swap Recommendations Application Note PDF 67 KB May 5, 2014
AN-837 Overdriving the Crystal Interface Application Note PDF 50 KB May 5, 2014
AN-832 Timing Budget and Accuracy Application Note PDF 48 KB May 5, 2014
AN-830 Quartz Crystal Drive Level Application Note PDF 59 KB May 4, 2014
AN-827 Application Relevance of Clock Jitter Application Note PDF 1.06 MB Apr 23, 2014
AN-815 Understanding Jitter Units Application Note PDF 476 KB Apr 23, 2014
AN-802 Crystal-Measuring Oscillator Negative Resistance Application Note PDF 52 KB Mar 11, 2014
AN-805 Recommended Ferrite Beads Application Note PDF 38 KB Jan 14, 2014
AN-801 Crystal-High Drive Level Application Note PDF 109 KB Jan 14, 2014
AN-806 Power Supply Noise Rejection Application Note PDF 353 KB Jan 14, 2014
PCNs & PDNs
PCN# : A1606-02 Add Greatek Taiwan as Alternate Assembly Product Change Notice PDF 567 KB Aug 25, 2016
PCN# : A1309-01 Changed of Traceability Mark Format Product Change Notice PDF 439 KB Oct 10, 2013
PCN# : TB1303-02 Change of Tape & Reel Packing Method for Selective Products Product Change Notice PDF 361 KB Mar 23, 2013
PCN# : A1208-01R1 Gold to Copper Wire Product Change Notice PDF 254 KB Dec 20, 2012
Other
Timing Solutions Products Overview Overview PDF 964 KB Sep 19, 2018
IDT Clock Generation Overview 日本語 Overview PDF 1.83 MB Apr 28, 2016
IDT Clock Distribution Overview 日本語 Overview PDF 3.79 MB Apr 24, 2016

Software & Tools

Title Other Languages Type Format File Size Date
844256i IBIS Model Model - IBIS ZIP 50 KB Aug 25, 2010