VCSO Based GbE Clock Generator

The M908-01 is a PLL (Phase Locked Loop) based clock generator that uses an internal VCSO (Voltage Controlled SAW Oscillator) to produce a very low jitter output clock. It is ideal for Gigabit Ethernet. The output clock (frequency of 156.25 or 187.50MHz for example) is provided from eight LVPECL clock output pairs. (Specify frequency at time of order.) The accuracy of the output frequency is assured by the internal PLL, which phase-locks the internal VCSO to the reference input frequency (25 or 30MHz for example). The input reference can either be an external crystal, utilizing the internal crystal oscillator, or a stable external clock source such as a packaged crystal oscillator.


  • Output clock frequency from 125MHz to 190MHz (Consult factory for frequency availability)
  • Eight identical LVPECL output pairs
  • Integrated SAW (surface acoustic wave) delay line
  • Low jitter 0.7ps RMS (over 12kHz-20MHz)
  • Ideal for Gigabit Ethernet clock reference
  • Output-to-output skew < 100ps
  • External XTAL or LVCMOS reference input
  • Industrial temperature grade available
  • Single 3.3V power supply
  • Small 9 x 9 mm SMT (surface mount) package

Product Options

Orderable Part ID Part Status Pkg. Code Pkg. Type Lead Count (#) Temp. Grade Pb (Lead) Free Carrier Type Buy Sample
M908-01-156.2500 Obsolete CG36 CLCC 36 C Yes Tube Availability
M908-01-156.2500T Obsolete CG36 CLCC 36 C Yes Reel Availability