FemtoClock® Crystal-to-3.3V LVPECL Frequency Synthesizer With/Integrated Fanout Buffer

The 843256I is a Crystal-to-3.3V LVPECL Clock Synthesizer/Fanout Buffer designed for Fibre Channel 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 843256I make it an ideal clock for these demanding applications.

Features

  • Six 3.3V differential LVPECL output pairs
  • Output frequency range: 62.5MHz to 625MHz
  • Crystal input frequency range: 15.625MHz to 25.5MHz
  • RMS phase jitter at 156.25MHz, using a 25MHz crystal (1.875MHz to 20MHz): 0.41ps (typical) @ 3.3V
  • Operating supply modes: Core/Output 3.3V/3.3V 3.3V/2.5V
  • -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
843256BGILF Active EJG24 TSSOP 24 I Yes Tube Availability
843256BGILFT Active EJG24 TSSOP 24 I Yes Reel Availability

Technical Documentation

Title Other Languages Type Format File Size Date
Datasheets & Errata
843256i Final Data Sheet Datasheet PDF 262 KB May 28, 2015
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-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
Other
The IDT Communications Products Advantage Overview PDF 4.00 MB Mar 21, 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