The 8R45252I is a 3.3V,2.5V CML clock generator designed for Ethernet applications. The device synthesizes either a 50MHz, 62.5MHz, 100MHz, 125MHz, 156.25MHz, 250MHz or 312.5MHz clock signal with excellent phase jitter performance. The clock signal is distributed to two low-skew differential CML outputs. The device is suitable for driving the reference clocks of Ethernet PHYs. The device supports 3.3V and 2.5V voltage supply and is packaged in a small, lead-free (RoHS 6) 32-lead VFQFN package. The extended temperature range supports telecommunication, wireless infrastructure and networking end equipment requirements. The device is a member of the family of High Performance Clock Solutions from IDT.

Features

  • Clock generation of: 50MHz, 62.5MHz, 100MHz, 125MHz, 156.25MHz, 250MHz and 312.5MHz
  • Two differential CML clock output pairs
  • Crystal interface designed for 25MHz, 18pF parallel resonant crystal
  • RMS phase jitter @ 125MHz, using a 25MHz crystal (1.875MHz – 20MHz): 400fs (typical), 3.3V
    Offset                        Noise Power
      100Hz.................... -102.4 dBc/Hz
        1kHz.................... -119.4 dBc/Hz
      10kHz.................... -124.8 dBc/Hz
    100kHz.................... -125.7 dBc/Hz
  • LVCMOS interface levels for the control inputs
  • Full 3.3V and 2.5V supply voltage
  • Available in lead-free (RoHS 6) 32 VFQFN package
  • -40°C to 85°C ambient operating temperature

Product Options

Part Number Part Status Pkg. Type Lead Count (#) Temp. Grade Pb (Lead) Free Carrier Type Buy Sample
Obsolete VFQFPN 32 I Yes Tray
Availability
Obsolete VFQFPN 32 I Yes Reel
Availability

Documentation & Downloads

Title language Type Format File Size Date
Datasheets & Errata
8R45252I Data Sheet Datasheet PDF 390 KB
Application Notes & White Papers
AN-828 Termination - LVPECL Application Note PDF 322 KB
AN-831 The Crystal Load curve Application Note PDF 395 KB
AN-844 Termination - AC Coupling Clock Receivers Application Note PDF 170 KB
AN-842 Thermal Considerations in Package Design and Selection Application Note PDF 495 KB
AN-840 Jitter Specifications for Timing Signals Application Note PDF 442 KB
AN-838 Peak-to-Peak Jitter Calculations Application Note PDF 115 KB
AN-839 RMS Phase Jitter Application Note PDF 233 KB
AN-834 Hot-Swap Recommendations Application Note PDF 153 KB
AN-837 Overdriving the Crystal Interface Application Note PDF 133 KB
AN-832 Timing Budget and Accuracy Application Note PDF 131 KB
AN-836 Differential Input to Accept Single-ended Levels Application Note PDF 120 KB
AN-835 Differential Input with VCMR being VIH Referenced Application Note PDF 160 KB
AN-830 Quartz Crystal Drive Level Application Note PDF 143 KB
AN-827 Application Relevance of Clock Jitter Application Note PDF 1.15 MB
AN-815 Understanding Jitter Units Application Note PDF 565 KB
AN-802 Crystal-Measuring Oscillator Negative Resistance Application Note PDF 136 KB
AN-801 Crystal-High Drive Level Application Note PDF 202 KB
AN-806 Power Supply Noise Rejection Application Note PDF 438 KB
AN-805 Recommended Ferrite Beads Application Note PDF 121 KB
AN-803 Crystal Timing Budget and Accuracy for Renesas Timing Clock Products Application Note PDF 108 KB
PCNs & PDNs
PCN# : A1904-01 Add Greatek, Taiwan as an Alternate Assembly Facility Product Change Notice PDF 983 KB
PDN# : CQ-19-01(R1) Quarterly Market Declined PDN Product Discontinuation Notice PDF 1014 KB
PDN# : CQ-19-01 Quarterly Market Declined PDN Product Discontinuation Notice PDF 537 KB
PCN# : A1511-01(R1) Add SPEL India as Alternate Assembly Location Product Change Notice PDF 596 KB
PCN# : A1511-01 Add SPEL India as Alternate Assembly Location Product Change Notice PDF 544 KB
Other
IDT Clock Generation Overview 日本語 Overview PDF 1.83 MB