Crystal oven

About: Crystal oven is a research topic. Over the lifetime, 955 publications have been published within this topic receiving 10380 citations. The topic is also known as: oven-controlled crystal oscillator & OCXO.

Evaluation of Mechanisms for Low-Dose Frequency Shifts in Crystal Oscillators

Abstract: Two possible causes for the observed frequency shift of a crystal oscillator due to a small radiation dose to the crystal have been analyzed. Removal of mass from the surface of the crystal by the radiation does not appear to be a plausible cause for the frequency shift. However, the electric fields and voltages created in the crystal by charge that is photoemitted from the walls of the can around the crystal and is then trapped in the crystal are relatively large and could possibly produce the observed frequency shift. These trapped charges produce both normal and tangential electric fields inside the crystal. Consequently, the difference in this radiation-induced frequency shift for SC-cut resonators, which are primarily sensitive to normal stresses, and for AT-cut resonators, which are primarily sensitive to tangential stresses, is less than the difference in their normal voltage sensitivities.

Apparatus for determining frequency versus acceleration characteristics for crystals

Abstract: The disclosed apparatus for determining the acceleration induced changes in the electrical characteristics of a quartz crystal includes all the apparatus necessary for subjecting the crystal to random acceleration forces and simultaneously determining the electrical characteristics of the crystal. More specifically a vibration generator is provided to subject the crystal under test to random vibrations of a predetermined acceleration. A low noise signal generator provides a signal at the resonant frequency of the crystal. The crystal couples the output of the low noise signal generator to a phase detector to determine the phase shift of the crystal. The output signal of the phase shift detector is analyzed to determine the acceleration versus electrical characteristics of the crystal under test.

Overtone crystal oscillator having resonance amplifier in feedback path

Abstract: In an overtone crystal oscillator comprising a crystal oscillator having a feedback loop and a resonance amplifier whose amplitude characteristic has an overshoot in the range of the resonant frequency of the resonance amplifier and which is arranged in the feedback loop of the crystal oscillator, the resonant frequency of the resonance amplifier is between the frequency of the overtone to be generated and the next lower oscillation frequency of the crystal oscillator, while signals in the frequency range of the next lower oscillation frequency(ies) in relation to signals in the frequency range of the overtone to be generated in the feedback loop, particularly in the resonance amplifier, have such a phase shift that the overtone crystal oscillator cannot oscillate at the frequencies of the next lower oscillation frequency(ies) and that it only oscillates at the frequency of the overtone to be generated.

Oven controlled FBAR oscillator

Abstract: Recent work with chip scale integrated FBAR oscillators has highlighted the fact that the temperature sensitivity is similar to SAW resonators. This sensitivity is significantly higher than quartz crystal oscillators, and limits the application of the technology. This investigation looks at the feasibility of stabilizing the frequency of the oscillator with a heater resistor and sensor resistor integrated into close proximity with the resonator, and an on-chip temperature feedback network.