The ICS650-21 is a low cost, low-jitter, high-performance clock synthesizer for system peripheral applications. Using analog/digital Phase Locked Loop (PLL) techniques, the device accepts a parallel resonant 25 MHz crystal input to produce up to eight output clocks. The device provides clocks for PCI, SCSI, Fast Ethernet, Ethernet, USB, and AC97. The user can select one of three USB frequencies and also one of two AC97 audio frequencies. The OE pin puts all outputs into a high-impedance state for board level
testing. All frequencies are generated with less than one ppm error, meeting the demands of SCSI and Ethernet clocking.


  • Packaged in 20-pin SSOP (QSOP)
  • Pb (lead) free package, RoHS compliant 
  • Lower jitter version of ICS650-01
  • Operating voltage of 3.3 V or 5 V
  • Zero ppm synthesis error in all clocks
  • Inexpensive 25 MHz crystal or clock input
  • Provides Ethernet and Fast Ethernet clocks
  • Provides SCSI clocks
  • Provides PCI clocks
  • Selectable AC97 audio clock
  • Selectable USB clock
  • OE pin tri-states the outputs for testing
  • Selectable frequencies on three clocks
  • Duty cycle of 45/55 for Processor clock and Audio clock
  • Advanced, low-power CMOS process
  • Industrial temperature range available


器件号 Part Status Pkg. Type Lead Count (#) Temp. Grade Pb (Lead) Free Carrier Type Buy Sample
Obsolete QSOP 20 I 是的 Tube
Obsolete QSOP 20 I 是的 Reel
Not Recommended for New Designs QSOP 20 C 是的 Tube
Not Recommended for New Designs QSOP 20 C 是的 Reel


文档标题 其他语言 类型 文档格式 文件大小 日期
650-21 Datasheet 数据手册 PDF 249 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-842 Thermal Considerations in Package Design and Selection 应用文档 PDF 495 KB
AN-803 Crystal Timing Budget and Accuracy for IDT Timing Clock Products 应用文档 PDF 128 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-827 Application Relevance of Clock Jitter 应用文档 PDF 1.15 MB
AN-815 Understanding Jitter Units 应用文档 PDF 565 KB
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-806 Power Supply Noise Rejection 应用文档 PDF 438 KB
AN-805 Recommended Ferrite Beads 应用文档 PDF 121 KB
PCN# : A1808-01 Transfer Assembly Location from Amkor Philippines for select pacakges 产品变更通告 PDF 39 KB
PDN# : CQ-18-03 Product Discontinuance Notice 产品停产通告 PDF 218 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# : A1208-01R1 Gold to Copper Wire 产品变更通告 PDF 254 KB
IDT Clock Generation Overview 日本語 概览 PDF 1.83 MB