FemtoClock® Crystal-to-0.7V Differential

The 841484I is an optimized PCIe and sRIO clock generator. The device uses a 25MHz parallel resonant crystal to generate 100MHz, 125MHz, 200MHz and 400MHz clock signals, replacing solutions requiring multiple oscillator and fanout buffer solutions. The device has excellent phase jitter suitable to clock components requiring precise and low jitter PCIe, sRIO or both clock signals. The device also supports a configurable spread-spectrum generation for PCIe applications. Designed for telecom, networking and industrial applications, the 841484I can also drive the high-speed sRIO and PCIe SerDes clock inputs of communications processors, DSPs, switches and bridges.


  • Four 0.7V differential HCSL outputs: configurable for PCIe (100MHz or 200MHz) and sRIO (125MHz) clock signals
  • One LVCMOS/LVTTL reference clock output
  • Selectable crystal oscillator interface, 25MHz, 18pF parallel resonant crystal or LVCMOS/LVTTL single-ended reference clock input
  • Supports the following output frequencies: 100MHz, 125MHz, 200MHz or 400MHz
  • VCO frequency range: 950MHz - 1.25GHz
  • Configurable spread-spectrum generation for PCIe
  • PLL bypass and output enable
  • RMS phase jitter @ 200MHz, using a 25MHz crystal (12kHz - 20MHz): 1.21ps (typical)
  • PCI Express (2.5 Gb/S), Gen 2 (5 Gb/s) and Gen 3 (8 Gb/s) jitter compliant (REF_OUT disabled)
  • Full 3.3V 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
841484DKILF Last Time Buy NLG32P1 VFQFPN 32 I Yes Tray Availability
841484DKILFT Last Time Buy NLG32P1 VFQFPN 32 I Yes Reel Availability

Technical Documentation

Title Other Languages Type Format File Size Date
Datasheets & Errata
841484I Datasheet Datasheet PDF 803 KB Nov 13, 2012
PDN# : CQ-17-04(R1) Product Discontinuance Notice Product Discontinuation Notice PDF 606 KB Nov 29, 2017
PDN# : CQ-17-04 Product Discontinuance Notice Product Discontinuation Notice PDF 599 KB Aug 24, 2017
PCN# : A1511-01(R1) Add SPEL India as Alternate Assembly Location Product Change Notice PDF 596 KB Jan 27, 2016
PCN# : A1511-01 Add SPEL India as Alternate Assembly Location Product Change Notice PDF 544 KB Nov 12, 2015
The IDT Consumer Products Advantage Overview PDF 4.01 MB Jun 30, 2017
IDT PCI Express Solutions Overview 日本語, 简体中文 Overview PDF 768 KB Apr 19, 2017
The IDT Automotive Advantage Overview PDF 3.55 MB May 26, 2017
The IDT Communications Products Advantage Overview PDF 2.54 MB Feb 13, 2017
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

News & Additional Resources