A crystal oscillator with low acceleration sensitivity

摘要

Cantilever-mounted resonators are compact and low-profile but suffer high sensitivity to acceleration in the direction of the cantilever. To overcome this sensitivity an oscillator is arranged to use two beam resonators 42,44 mounted in opposite directions so that the acceleration sensitivities of the resonators cancel each other. The resonators may be electrically connected in parallel in the oscillator circuit (figure 5). The resonators may be BAW (Bulk Acoustic Wave) or SAW (Surface Acoustic Wave) piezoelectric crystals or MEMS (Micro Electro-Mechanical System) devices. The resonators may be mounted in separate housings (figure 7) or may be located at opposite ends of a single centre-mounted beam (figure 8).