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840N021I

FemtoClock® NG Crystal-to-LVCMOS/ LVTTL Clock Synthesizer

Alternative Products
NOTICE - The following device(s) are recommended alternatives:
Functional replacement
The 840N021 is a LVCMOS/LVTTL clock synthesizer designed for Ethernet applications. The device generates a 125MHz clock signal from a 25MHz crystal with excellent phase jitter performance. The device uses IDT’s fourth generation FemtoClock® NG technology for an optimum of high clock frequency, low phase noise performance and low power consumption.The device supports 2.5V or 3.3V voltage supply and is packaged in a small, lead-free (RoHS 6) 8-lead TSSOP package. The extended temperature range supports wireless infrastructure, telecommunication and networking end equipment requirements. The device is a member of the high-performance clock family from IDT.

Features

  • Fourth generation FemtoClock® NG technology
  • 125MHz output clock synthesized from a 25MHz fundamental mode crystal
  • One 2.5V or 3.3V LVCMOS/LVTTL clock output
  • Crystal interface designed for a 12pF parallel resonant crystal
  • RMS phase jitter @ 125MHz, using a 25MHz crystal (1.875MHz - 20MHz): 0.156ps (maximum)
  • RMS phase jitter @ 100MHz, using a 20MHz crystal (12kHz - 20MHz): 0.451ps (maximum)
  • LVCMOS interface level for the output enable input
  • Full 2.5V or 3.3V supply voltage
  • Lead-free (RoHS 6) packaging
  • -40°C to 85°C ambient operating temperature​

Product Options

Orderable Part IDPart StatusPkg. CodePkg. TypeLead Count (#)Temp. GradePb (Lead) FreeCarrier TypeSample & Buy
840N021BGILFObsoletePGG8TSSOP8IYesTubeCheck Availability
840N021BGILFTObsoletePGG8TSSOP8IYesReelCheck Availability

Documents

Technical Documentation

Title Type Format File Size Datesort icon
Datasheets & Errata
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840N021I Data Sheet Datasheet PDF 236 KB Aug 14, 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-845 Termination - LVCMOS Application Note PDF 62 KB May 13, 2014
show all (18)
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AN-842 Thermal Considerations in Package Design and Selection Application Note PDF 403 KB May 12, 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-803 Crystal Timing Budget and Accuracy for IDT Timing Clock Products Application Note PDF 44 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-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-837 Overdriving the Crystal Interface Application Note PDF 50 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-801 Crystal-High Drive Level Application Note PDF 109 KB Jan 15, 2014
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AN-805 Recommended Ferrite Beads Application Note PDF 38 KB Jan 15, 2014
PCNs & PDNs
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PDN# : CQ-15-04 Quarterly Market Declined PDN Product Discontinuation Notice PDF 545 KB Aug 13, 2015