When oscillators need to operate in a High Shock and Vibration environment such as in avionics, missiles, vehicles, construction equipment and industrial applications, the oscillator must be specially designed to both survive and operate in these environments. The main performance parameter that is affected from vibration is phase noise. Further details about these affects can be found in the g-sensitivity section of the website. When designing for survival in harsh environments, the designer must be concerned about both the crystal design and the oscillator design. It is a challenge to create an oscillator with state of the art performance while maintaining a small form factor. Fre-tech's 30+ years of designing High Shock and Vibration products has resulted is the table of products below. Fre-tech also has extensive experience working with our customers to create a rugged interface between our oscillator and our customer's system. As a result, Fre-tech has a large library of capabilities that are not depicted in this table. Please contact Fre-tech if you have a need for custom High Shock or Vibration requirement.

G-sensitivity is defined as a change in frequency resulting from an acceleration force applied to an oscillator. It is often expressed in terms of ppb/g. How does this affect performance? When an oscillator is used in an environment conducive to vibration, the frequency of the vibration will modulate the carrier frequency degrading the phase noise performance of the oscillator. This phenomenon is similar for both random and sine vibration and is also very deterministic meaning the magnitude of the induced phase noise degradation can be calculated if the g-sensitivity of the oscillator is known.  Please follow the link to an excerpt from John's tutorial which will provide a more detailed description of g-sensitivity and the equations for calculating the resulting phase noise in random and sine vibration environments.