The XK devices are a second-generation follow-on to the XF ProXO high-performance oscillators designed for high-performance applications and are often referred to as ProXO II. The XK family is optimized for communications applications requiring ultra-low jitter and is available in the industry’s smallest package. Each device can be factory programmed with up to 3 frequencies and/or output types.

The differential oscillator supports 20 commonly used networking frequencies from 50MHz to 1250MHz. It features 55fs RMS jitter (typ.), excellent immunity to power supply noise and environmental hazards, industry-standard package sizes down to 1.8 x 1.4 mm and operating temperature support from -40°C to 85°C.


  • Phase jitter (12kHz to 20MHz): 55fs RMS (typ.) at 156.25MHz
  • Package options:
    • 1.8 × 1.4 × 0.85 mm (1.6 × 1.2 mm footprint compatible)
    • 2.0 × 1.6 × 0.85 mm
    • 2.5 × 2.0 × 0.7 mm
    • 3.2 × 2.5 × 0.7 mm
  • Factory programmable with up to three frequencies (from 50MHz to 1250MHz) and/or output types
  • Output types: LVCMOS, LVDS, HCSL, LVPECL, CML
  • Supply voltage: 1.8V, 2.5V or 3.3V
  • Total stability (including temperature, power supply, and aging):
    • ± 30ppm (1.8V)
    • ± 50ppm (2.5V, 3.3V)
  • Operating temperatures: -40°C to +85°C




Design & Development


ProXO2 High Performance Oscillators

Learn about how the ProXO2 family delivers the industry’s smallest package and uncompromised performance at 55fs typical phase jitter.