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843256I - Block Diagram
843256I - Pinout

843256I

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 IDPart StatusPkg. CodePkg. TypeLead Count (#)Temp. GradePb (Lead) FreeCarrier TypeSample & Buy
843256BGILFActiveEJG24TSSOP24IYesTubeCheck Availability
843256BGILFTActiveEJG24TSSOP24IYesReelCheck Availability

Documents

Technical Documentation

Title Type Format File Size Datesort icon
Datasheets & Errata
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843256i Final Data Sheet Datasheet PDF 262 KB May 29, 2015
Apps Notes & White Papers
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AN-828 Termination - LVPECL Application Note PDF 229 KB Jul 5, 2016
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AN-831 The Crystal Load curve Application Note PDF 308 KB Sep 22, 2014
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AN-842 Thermal Considerations in Package Design and Selection Application Note PDF 403 KB May 12, 2014
show all (17)
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AN-803 Crystal Timing Budget and Accuracy for IDT Timing Clock Products Application Note PDF 44 KB May 8, 2014
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AN-840 Jitter Specifications for Timing Signals Application Note PDF 349 KB May 8, 2014
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AN-839 RMS Phase Jitter Application Note PDF 149 KB May 7, 2014
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AN-838 Peak-to-Peak Jitter Calculations Application Note PDF 32 KB May 7, 2014
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AN-837 Overdriving the Crystal Interface Application Note PDF 50 KB May 6, 2014
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AN-834 Hot-Swap Recommendations Application Note PDF 67 KB May 6, 2014
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AN-832 Timing Budget and Accuracy Application Note PDF 48 KB May 6, 2014
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AN-830 Quartz Crystal Drive Level Application Note PDF 59 KB May 5, 2014
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AN-827 Application Relevance of Clock Jitter Application Note PDF 1.06 MB Apr 24, 2014
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AN-815 Understanding Jitter Units Application Note PDF 476 KB Apr 24, 2014
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AN-802 Crystal-Measuring Oscillator Negative Resistance Application Note PDF 52 KB Mar 12, 2014
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AN-806 Power Supply Noise Rejection Application Note PDF 353 KB Jan 15, 2014
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AN-805 Recommended Ferrite Beads Application Note PDF 38 KB Jan 15, 2014
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AN-801 Crystal-High Drive Level Application Note PDF 109 KB Jan 15, 2014
PCNs & PDNs
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PCN# : A1606-02 Add Greatek Taiwan as Alternate Assembly Product Change Notice PDF 567 KB Aug 26, 2016
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PCN# : A1309-01 Changed of Traceability Mark Format Product Change Notice PDF 439 KB Oct 11, 2013
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PCN# : TB1303-02 Change of Tape & Reel Packing Method for Selective Products Product Change Notice PDF 361 KB Mar 24, 2013