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.


  • 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


器件号 Part Status Pkg. Type Lead Count (#) Temp. Grade Pb (Lead) Free Carrier Type Buy Sample
Active SOIC 8 I 是的 Tube
Active SOIC 8 I 是的 Reel


文档标题 language 类型 文档格式 文件大小 日期
251 Datasheet 数据手册 PDF 290 KB
应用指南 & 白皮书
AN-828 Termination - LVPECL 应用文档 PDF 322 KB
AN-831 The Crystal Load curve 应用文档 PDF 395 KB
AN-844 Termination - AC Coupling Clock Receivers 应用文档 PDF 170 KB
AN-845 Termination - LVCMOS 应用文档 PDF 146 KB
AN-842 Thermal Considerations in Package Design and Selection 应用文档 PDF 495 KB
AN-840 Jitter Specifications for Timing Signals 应用文档 PDF 442 KB
AN-838 Peak-to-Peak Jitter Calculations 应用文档 PDF 115 KB
AN-839 RMS Phase Jitter 应用文档 PDF 233 KB
AN-832 Timing Budget and Accuracy 应用文档 PDF 131 KB
AN-834 Hot-Swap Recommendations 应用文档 PDF 153 KB
AN-830 Quartz Crystal Drive Level 应用文档 PDF 143 KB
AN-815 Understanding Jitter Units 应用文档 PDF 565 KB
AN-827 Application Relevance of Clock Jitter 应用文档 PDF 1.15 MB
AN-802 Crystal-Measuring Oscillator Negative Resistance 应用文档 PDF 136 KB
AN-801 Crystal-High Drive Level 应用文档 PDF 202 KB
AN-805 Recommended Ferrite Beads 应用文档 PDF 121 KB
AN-806 Power Supply Noise Rejection 应用文档 PDF 438 KB
AN-803 Crystal Timing Budget and Accuracy for Renesas Timing Clock Products 应用文档 PDF 108 KB
PCN# : A1812-01 Add Greatek Taiwan as Alternate Assembly Location 产品变更通告 PDF 26 KB
PCN# : A1602-01(R1) Add Greatek Taiwan as Alternate Assembly 产品变更通告 PDF 611 KB
PCN# : A1602-01 Add Greatek Taiwan as Alternate Assembly 产品变更通告 PDF 611 KB
PCN# : TB1504-01R1 Qty per Reel Standardization for Selective Packages 产品变更通告 PDF 95 KB
PCN# : TB1504-01 Qty per Reel Standardization for Selective Packages 产品变更通告 PDF 50 KB
PCN# : TB1303-02 Change of Tape & Reel Packing Method for Selective Products 产品变更通告 PDF 361 KB
PCN# A-0607-06 MMT Thailand as Alternate Assembly Facility for PLCC, SOIC 150mil/300mil 产品变更通告 PDF 223 KB
VersaClock Family Overview 日本語 概览 PDF 376 KB
IDT Clock Generation Overview 日本語 概览 PDF 1.83 MB