Airbus Defence and Space


SPXO quartz clock oscillator

The SPXO is a space3-qualified high frequency quartz-crystal-controlled clock for satellite data-bus systems. It is a simple-packaged crystal oscillator using an overtone AT-cut resonator, fabricated from Airbus Defence and Space-grown High Purity Quartz. This material is the purest and most highly qualified quartz in the world and provides the SPXO resonator with excellent intrinsic radiation tolerance. The design utilises Advanced CMOS AC logic devices for low power and high speed. The circuit is implemented using surface-mount technology, with hermetically encapsulated integrated circuits, in a vented aluminium box.

Features / technical details

Main Features

  • Precision AT-cut resonator
  • Space qualified
  • Uses Airbus Defence and Space-grown High Purity Quartz for radiation tolerance
  • Hermetic silicon IC’s, surface-mount format


Frequency 20 to 100MHz
Stability (all causes) <±100ppm (10 years)
Stability (with temperature) ±50ppm
Stability (with setting) ±20ppm
Stability (with voltage) ±10ppm
Ageing ±20ppm
Duty cycle 50:50 nom
Rise/fall time <5 nSec
Output CMOS: Square
Power consumption 300 mW nom.
Supply 5 ±0.5 volts
Size 32 x 22 x 10 mm
Weight <20 grams


  • Small space-qualified clock oscillator
  • Radiation tolerant – total dose
  • Mechanically robust – to withstand launch vibration and solar panel deployment


  • PCB through-hole mounting
  • RF, +5V & GND


  • Operating temperature: -30°C to +90°C
  • Radiation tolerance: 50 krad


The SPXO oscillator can be used as the microprocessor clock to provide the synchronisation signal in spaceborne applications where quartz crystal controlled timing stability is required together with low mass, size and power consumption.

Reference customers