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MK1581-01 - Block Diagram
MK1581-01 - Pinout


Low Phase Noise T1/E1 Clock Generator

The MK1581-01 provides synchronization and timing control for T1 and E1 based network access or multitrunk telecommunication systems. The device accepts an 8 kHz frame clock input and uses an on-chip VCXO to produce a synchronized low phase noise clock output. This monolithic IC, combined with an external inexpensive quartz crystal, can be used to replace a more costly hybrid VCXO retiming module. Through selection of external loop filter components values, the device can be tailored to meet the system’s clock jitter attenuation requirements. Low-pass jitter attenuation characteristics in the Hz range are possible.


  • Generates a T1 (1.544 MHz) or E1 (2.048 MHz) output clock from an 8kHz frame clock input
  • Configurable jitter attenuation characteristics, excellent for use as a Stratum source de-jitter circuit
  • VCXO-based clock generation ensures very low jitter and phase noise generation
  • Output clock is phase and frequency locked to the input reference clock
  • +115ppm minimum crystal frequency pullability range, using recommended crystal
  • Industrial temperature range
  • Low power CMOS technology
  • 16 pin TSSOP package
  • Single 3.3 V power supply

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)
1LVCMOS1.544000, 2.0480000.0080001LVCMOS13.33.3

Product Options

Orderable Part IDPart StatusPkg. CodePkg. TypeLead Count (#)Temp. GradePb (Lead) FreeCarrier TypeSample & Buy
MK1581-01GILFObsoletePGG16TSSOP16IYesTubeCheck Availability
MK1581-01GILFTRObsoletePGG16TSSOP16IYesReelCheck Availability


Technical Documentation

Title Type Format File Size Datesort icon
Datasheets & Errata
MK1581-01 Datasheet Datasheet PDF 242 KB May 17, 2010
Apps Notes & White Papers
AN-828 Termination - LVPECL Application Note PDF 229 KB Jul 5, 2016
AN-831 The Crystal Load curve Application Note PDF 308 KB Sep 22, 2014
AN-842 Thermal Considerations in Package Design and Selection Application Note PDF 403 KB May 12, 2014
show all (14)
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-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-800 Approved VCXO Crystals Application Note PDF 63 KB Jan 28, 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-14-06R1 Revised Product Discontinuance Notice Product Discontinuation Notice PDF 407 KB Sep 8, 2014
PDN# : CQ-14-06 MANUFACTURING DISCONTINUANCE NOTICE Product Discontinuation Notice PDF 192 KB Sep 4, 2014
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
show all (4)
PCN# : TB1303-02 Change of Tape & Reel Packing Method for Selective Products Product Change Notice PDF 361 KB Mar 24, 2013