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810252BI-03 - Block Diagram
810252BI-03 - Pinout


VCXO Jitter Attenuator And FemtoClock® Multiplier

Alternative Products
NOTICE - The following device(s) are recommended alternatives:
Functionally compatible
Functionally compatible
Functionally compatible

The 810252BI-03 is a member of the family of high performance clock solutions from IDT. The 810252BI-03 is a PLL based synchronous multiplier that is optimized for PDH or SONET to Ethernet clock jitter attenuation and frequency translation. The device contains two internal frequency multiplication stages that are cascaded in series. The first stage is a VCXO PLL that is optimized to provide reference clock jitter attenuation. The second stage is a FemtoClock® frequency multiplier that provides the low jitter, high frequency Ethernet output clock that easily meets Gigabit and 10 Gigabit Ethernet jitter requirements. Pre-divider and output divider multiplication ratios are selected using device selection control pins. The multiplication ratios are optimized to support most common clock rates used in PDH, SONET and Ethernet applications. The VCXO requires the use of an external, inexpensive pullable crystal. The VCXO uses external passive loop filter components which allows configuration of the PLL loop bandwidth and damping characteristics. The device is packaged in a space-saving 32-TQFP, E-Pad and 32- VFQFN packages and supports industrial temperature range.


  • Two LVCMOS/LVTTL outputs, 17? impedance Each output supports independent frequency selection at 25MHz, 62.5MHz, 125MHz, and 156.25MHz
  • Two differential inputs support the following input types: LVPECL, LVDS, LVHSTL, SSTLHCSL
  • Accepts input frequencies from 8kHz to 155.52MHz including 8kHz, 1.544MHz, 2.048MHz, 19.44MHz, 25MHz, 77.76MHz, 125MHz and 155.52MHz
  • Attenuates the phase jitter of the input clock by using a lowcost pullable fundamental mode VCXO crystal
  • VCXO PLL bandwidth can be optimized for jitter attenuation and reference tracking using external loop filter connection
  • FemtoClock frequency multiplier provides low jitter, high frequency output
  • Absolute pull range: ±50ppm
  • FemtoClock VCO frequency: 625MHz
  • RMS phase jitter @ 125MHz, using a 25MHz crystal (12kHz - 20MHz): 1.1ps (typical)
  • 3.3V supply voltage
  • -40°C to 85°C ambient operating temperature
  • Available in lead-free (RoHS 6) package

Product Specification

Outputs (#)Output TypeOutput Freq Range (MHz)Input Freq (MHz)Inputs (#)Input TypeOutput Banks (#)Core Voltage (V)Output Voltage (V)Output Skew (ps)Phase Jitter Typ RMS (ps)Phase Jitter Max RMS (ps)
2LVCMOS25.000000 - 156.2500000.008000 - 155.5200002HCSL, SSTL, HSTL, LVDS, LVPECL23.33.31301.100

Product Options

Orderable Part IDPart StatusPkg. CodePkg. TypeLead Count (#)Temp. GradePb (Lead) FreeCarrier TypeSample & Buy
810252BKI-03LFObsoleteNLG32VFQFPN32IYesTrayCheck Availability
810252BKI-03LFTObsoleteNLG32VFQFPN32IYesReelCheck Availability
810252BYI-03LFObsoleteDXG32PTQFP32IYesTrayCheck Availability
810252BYI-03LFTObsoleteDXG32PTQFP32IYesReelCheck Availability


Technical Documentation

Title Type Format File Size Datesort icon
Datasheets & Errata
810252BI-03 Data Sheet Datasheet PDF 444 KB Jul 29, 2016
Apps Notes & White Papers
AN-828 Termination - LVPECL Application Note PDF 229 KB Jul 5, 2016
AN-841 Pullable Crystal Selection and VCXO Tuning Application Note PDF 248 KB Sep 23, 2014
AN-831 The Crystal Load curve Application Note PDF 308 KB Sep 22, 2014
show all (19)
AN-849 Loop Filter Component Selection for VCXO Based PLLs Application Note PDF 132 KB May 14, 2014
AN-848 VCXO - Crystal Selection Application Note PDF 138 KB May 14, 2014
AN-847 VCXO - Absolute Pull Range Application Note PDF 70 KB May 13, 2014
AN-842 Thermal Considerations in Package Design and Selection Application Note PDF 403 KB May 12, 2014
AN-840 Jitter Specifications for Timing Signals Application Note PDF 349 KB May 8, 2014
AN-839 RMS Phase Jitter Application Note PDF 149 KB May 7, 2014
AN-838 Peak-to-Peak Jitter Calculations Application Note PDF 32 KB May 7, 2014
AN-835 Differential Input with VCMR being VIH Referenced Application Note PDF 77 KB May 6, 2014
AN-836 Differential Input to Accept Single-ended Levels Application Note PDF 37 KB May 6, 2014
AN-830 Quartz Crystal Drive Level Application Note PDF 59 KB May 5, 2014
AN-827 Application Relevance of Clock Jitter Application Note PDF 1.06 MB Apr 24, 2014
AN-815 Understanding Jitter Units Application Note PDF 476 KB Apr 24, 2014
AN-802 Crystal-Measuring Oscillator Negative Resistance Application Note PDF 52 KB Mar 12, 2014
AN-801 Crystal-High Drive Level Application Note PDF 109 KB Jan 15, 2014
AN-805 Recommended Ferrite Beads Application Note PDF 38 KB Jan 15, 2014
AN-806 Power Supply Noise Rejection Application Note PDF 353 KB Jan 15, 2014
PDN# CQ-14-05 MARKET DECLINED PRODUCT DISCONTINUANCE NOTICE Product Discontinuation Notice PDF 192 KB Sep 4, 2014