FemtoClock® SAS/SATA Clock Generator

The 844441I is a low jitter, high performance clock generator and a member of the FemtoClock® family of silicon timing products. The 844441I is designed for use in applications using the SAS and SATA interconnect. The 844441I uses an external, 25MHz, parallel resonant crystal to generate four selectable output frequencies: 75MHz, 100MHz, 150MHz, and 300MHz. This silicon based approach provides excellent frequency stability and reliability. The 844441I features down and center spread spectrum (SSC) clocking techniques.

Features

  • Designed for use in SAS, SAS-2, and SATA systems
  • Center (±0.25%) Spread Spectrum Clocking (SSC)
  • Down (-0.23% or -0.5%) SSC
  • Better frequency stability than SAW oscillators
  • One differential 2.5V LVDS output
  • Crystal oscillator interface designed for 25MHz (CL = 18pF) frequency
  • External fundamental crystal, ensures high reliability and low aging
  • Selectable output frequencies: 75MHz, 100MHz, 150MHz, 300MHz
  • Output frequency is tunable with external capacitors
  • RMS phase jitter @ 100MHz, using a 25MHz crystal (12kHz – 20MHz): 1.1936ps (typical)
  • 2.5V operating supply
  • -40°C to 85°C ambient operating temperature
  • Available in lead-free (RoHS 6) packages

Product Options

Orderable Part ID Part Status Pkg. Code Pkg. Type Lead Count (#) Temp. Grade Pb (Lead) Free Carrier Type Buy Sample
844441DGILF Obsolete PGG16 TSSOP 16 I Yes Tube Availability
844441DGILFT Obsolete PGG16 TSSOP 16 I Yes Reel Availability
844441DMI-100LF Obsolete DCG8 SOIC 8 I Yes Tube Availability
844441DMI-100LFT Obsolete DCG8 SOIC 8 I Yes Reel Availability
844441DMI-150LF Obsolete DCG8 SOIC 8 I Yes Tube Availability
844441DMI-150LFT Obsolete DCG8 SOIC 8 I Yes Reel Availability
844441DMI-300LF Obsolete DCG8 SOIC 8 I Yes Tube Availability
844441DMI-300LFT Obsolete DCG8 SOIC 8 I Yes Reel Availability
844441DMI-75LF Obsolete DCG8 SOIC 8 I Yes Tube Availability
844441DMI-75LFT Obsolete DCG8 SOIC 8 I Yes Reel Availability

Technical Documentation

Title Other Languages Type Format File Size Date
Datasheets & Errata
844441 Datasheet Datasheet PDF 350 KB Nov 2, 2016
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# : TB1504-01R1 Qty per Reel Standardization for Selective Packages Product Change Notice PDF 95 KB Oct 21, 2015
PDN# : CQ-15-04 Quarterly Market Declined PDN Product Discontinuation Notice PDF 545 KB Aug 12, 2015
PCN# : TB1504-01 Qty per Reel Standardization for Selective Packages Product Change Notice PDF 50 KB Jul 20, 2015
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