1-to-5 Differential-to-3.3V LVPECL PLL Clock Driver W/Dynamic Clock Switch

The 87993I is a PLL clock driver designed specifically for redundant clock tree designs. The device receives two differential LVPECL clock signals from which it generates 5 new differential LVPECL clock outputs. Two of the output pairs regenerate the input signal frequency and phase while the other three pairs generate 2x, phase aligned clock outputs. External PLL feedback is used to also provide zero delay buffer performance. The 87993I Dynamic Clock Switch (DCS) circuit continuously monitors both input CLK signals. Upon detection of a failure (CLK stuck HIGH or LOW for at least 1 period), the INP_BAD for that CLK will be latched (H). If that CLK is the primary clock, the DCS will switch to the good secondary clock and phase/frequency alignment will occur with minimal output phase disturbance. The typical phase bump caused by a failed clock is eliminated.

Features

  • 5 differential 3.3V LVPECL outputs
  • Selectable differential clock inputs
  • CLKx, nCLKx pair can accept the following differential input levels: LVPECL, LVDS, LVHSTL, HCSL, SSTL
  • Output frequency range: 50MHz to 250MHz
  • VCO range: 200MHz to 500MHz
  • External feedback for "zero delay" clock regeneration with configurable frequencies
  • Cycle-to-cycle jitter (RMS): 20ps (maximum)
  • Output skew: 70ps (maximum), within one bank
  • 3.3V supply voltage
  • -40°C to 85°C ambient operating temperature
  • Lead-Free package available

Product Options

Orderable Part ID Part Status Pkg. Code Pkg. Type Lead Count (#) Temp. Grade Pb (Lead) Free Carrier Type Buy Sample
87993AYILF Obsolete PRG32 TQFP 32 I Yes Tray Availability
87993AYILFT Obsolete PRG32 TQFP 32 I Yes Reel Availability

Technical Documentation

Title Other Languages Type Format File Size Date
Datasheets & Errata
87993I Datasheet Datasheet PDF 219 KB Feb 17, 2015
87993I Datasheet Datasheet PDF 300 KB Nov 15, 2010
Application Notes & White Papers
AN-828 Termination - LVPECL Application Note PDF 229 KB Jul 5, 2016
AN-835 Differential Input with VCMR being VIH Referenced Application Note PDF 77 KB May 10, 2014
AN-815 Understanding Jitter Units Application Note PDF 476 KB Apr 23, 2014
AN-844 Termination - AC Coupling Clock Receivers Application Note PDF 82 KB May 12, 2014
AN-842 Thermal Considerations in Package Design and Selection Application Note PDF 403 KB May 11, 2014
AN-840 Jitter Specifications for Timing Signals Application Note PDF 349 KB May 7, 2014
AN-836 Differential Input to Accept Single-ended Levels Application Note PDF 37 KB May 5, 2014
AN-834 Hot-Swap Recommendations Application Note PDF 67 KB May 5, 2014
AN-833 Differential Input Self Oscillation Prevention Application Note PDF 94 KB May 5, 2014
AN-827 Application Relevance of Clock Jitter Application Note PDF 1.06 MB Apr 23, 2014
AN-805 Recommended Ferrite Beads Application Note PDF 38 KB Jan 14, 2014
PCNs & PDNs
PDN# : CQ-16-04 QUARTER MARKET DECLINED PDN Product Discontinuation Notice PDF 560 KB Nov 2, 2016
PCN# : A1602-01(R1) Add Greatek Taiwan as Alternate Assembly Product Change Notice PDF 611 KB Apr 13, 2016
PCN# : A1602-01 Add Greatek Taiwan as Alternate Assembly Product Change Notice PDF 611 KB Feb 14, 2016
PCN# : TB1504-01R1 Qty per Reel Standardization for Selective Packages Product Change Notice PDF 95 KB Oct 21, 2015
PCN# : TB1504-01 Qty per Reel Standardization for Selective Packages Product Change Notice PDF 50 KB Jul 20, 2015
PCN# : A1401-02 Alternate Copper Wire Assembly Site Product Change Notice PDF 36 KB Feb 15, 2014
PCN# : TB1303-01 Change of Carrier Tape for TQFP-32, TQFP-48 Product Change Notice PDF 472 KB Mar 30, 2013
Other
The IDT Consumer Products Advantage Overview PDF 4.01 MB Jun 30, 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

Software & Tools

Title Other Languages Type Format File Size Date
87993i IBIS Model Model - IBIS ZIP 7 KB Apr 16, 2006

News & Additional Resources