Skip to main content


Ethernet Switch Clock Source

The 650-40A is a clock chip designed for use as a core clock in Ethernet Switch applications. Using IDT’s patented Phase-Locked Loop (PLL) techniques, the device takes a 25 MHz crystal input and produces various output clock frequencies as listed in Output Select Table.


  • Packaged in 16-pin TSSOP
  • Operating voltage of 3.3 V
  • Low power consumption
  • Input frequency of 25 MHz
  • Low long-term jitter
  • Separate supply voltage for clock outputs (2.5 / 3.3 V
    clock outputs)
  • OE control capability

Product Specification

Outputs (#)Output TypeOutput Freq Range (MHz)Inputs (#)Input TypeInput Freq (MHz)Output Voltage (V)Output Banks (#)Phase Jitter Typ RMS (ps)
30.00000025.0000002.5, 3.3

Product Options

Orderable Part IDPart StatusPkg. CodePkg. TypeLead Count (#)Temp. GradePb (Lead) FreeCarrier TypeSample & Buy
650G-40ALFObsoletePGG16TSSOP16CYesTubeCheck Availability
650G-40ALFTObsoletePGG16TSSOP16CYesReelCheck Availability


Technical Documentation

Title Type Format File Size Datesort icon
Datasheets & Errata
650-40A Datasheet Datasheet PDF 186 KB May 14, 2010
PCN# : TB1403-01 Changed in Carrier Tape, Plastic Reel and Quantity per Reel on TSSOP-14, TSSOP-16 Product Change Notice PDF 663 KB Apr 8, 2014
PDN# : U-12-03R4 PRODUCT DISCONTINUANCE NOTICE Product Discontinuation Notice PDF 72 KB Jun 20, 2013
PDN# : U-12-03R3 Product Discontinuation Notice PDF 72 KB Mar 31, 2013
show all (4)
PCN# : TB1303-02 Change of Tape & Reel Packing Method for Selective Products Product Change Notice PDF 361 KB Mar 24, 2013