The IDT251 is a low cost, single-output, field programmable clock synthesizer. The IDT251 can generate an output frequency from 314 kHz to 200 MHz and may employ Spread Spectrum techniques to reduce system electro-magnetic interference (EMI). Using IDT's VersaClock™ software to configure the PLL and output, the IDT251 contains a One-Time Programmable (OTP) ROM to allow field programmability. Programming features include 4 selectable configuration registers. The device employs Phase-Locked Loop (PLL) techniques to run from a standard fundamental mode, inexpensive crystal, or clock. It can replace multiple crystals and oscillators, saving board space and cost. The device also has a power-down feature that tri-states the clock outputs and turns off the PLLs when the PDTS pin is taken low. The IDT251 is also available in factory programmed custom versions for high-volume applications.

Features

  • 8-pin SOIC package
  • Four addressable registers
  • Input crystal frequency of 5 to 27 MHz
  • Clock input frequency of 3 to 150 MHz
  • Output clock frequencies up to 200 MHz
  • Configurable Spread Spectrum Modulation
  • Operating voltage of 3.3 V
  • Replaces multiple crystals and oscillators
  • Controllable output drive levels
  • Advanced, low-power CMOS process
  • Available in RoHS compliant packaging
  • click here for VersaClock Software page

Product Options

Part Number Part Status Pkg. Type Lead Count (#) Temp. Grade Pb (Lead) Free Carrier Type Buy Sample
Active SOIC 8 I Yes Tube
Availability
Active SOIC 8 I Yes Reel
Availability

Documentation & Downloads

Title language Type Format File Size Date
Datasheets & Errata
251 Datasheet Datasheet PDF 290 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-845 Termination - LVCMOS Application Note PDF 146 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-832 Timing Budget and Accuracy Application Note PDF 131 KB
AN-834 Hot-Swap Recommendations Application Note PDF 153 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# : A1812-01 Add Greatek Taiwan as Alternate Assembly Location Product Change Notice PDF 26 KB
PCN# : A1602-01(R1) Add Greatek Taiwan as Alternate Assembly Product Change Notice PDF 611 KB
PCN# : A1602-01 Add Greatek Taiwan as Alternate Assembly Product Change Notice PDF 611 KB
PCN# : TB1504-01R1 Qty per Reel Standardization for Selective Packages Product Change Notice PDF 95 KB
PCN# : TB1504-01 Qty per Reel Standardization for Selective Packages Product Change Notice PDF 50 KB
PCN# : TB1303-02 Change of Tape & Reel Packing Method for Selective Products Product Change Notice PDF 361 KB
PCN# A-0607-06 MMT Thailand as Alternate Assembly Facility for PLCC, SOIC 150mil/300mil Product Change Notice PDF 223 KB
Other
VersaClock Family Overview 日本語 Overview PDF 376 KB
IDT Clock Generation Overview 日本語 Overview PDF 1.83 MB